Completed research projects at the Swedish Livestock Research Centre

Last changed: 15 October 2024

Completed research projects at the Swedish Livestock Research Center

For more projects, please see the Swedish version of this page. 

Cattle: Completed projects

Cattle: Limited access to water for high-producing dairy cows (LN119)

Project duration september - november, 2024

This study aims to develop new knowledge to use available water resources on Swedish farms more effectively. This will potentially provide a solution for Swedish farmers experiencing water scarcity without negatively affecting production and animal welfare. Certain regions in Sweden periodically suffer from low groundwater levels, especially during summer. The Swedish Animal Welfare Act specifies requirements for oversight, feed and water, but the wording is unclear. It states: “Animals shall be provided with sufficient amount of feed and water of good quality. Feed, water and feeding routines shall be adapted to the needs of the animal,” but it does not further specify what this entails. The common practice is to offer the cows ad libitum access to fresh water around the clock. However, studies have shown that cows in those systems tend to use more water than they actually need. In this study, we want to investigate the possibilities of limiting access to water for high-producing dairy cows without negatively affecting their production and welfare.

Contact researchers

Anna Jansson, anna.jansson@slu.se, tele +18672106

Lea Managos, PhD student, lea.managos@slu.se, tele, +46722380077

Other participants in the project

Sammy Pettersson, research tehnician, sammy.pettersson@slu.se, tele +4618672114

 

Cattle: Preventing mastitis in dairy cows: unravelling transmission routes and reducing the use of antibiotics (LN110)

Project completed 2024

Mastitis is the most prevalent production disease in dairy herds world-wide, affecting animal welfare and production. Mastitis-causing bacteria are contagious and environmental pathogens, based upon important reservoirs and modes of transmission of each group. Social and behavioural interactions play a crucial role in the transmission of diseases on dairy farms. However, observational studies of social behaviour provide insufficient information to identify transmission routes.

Nowadays, Precision livestock farming technologies offer an excellent opportunity to continuously monitor the animals and understand the transmission routes of this multifactorial disease. Previous studies of our research group described the heterogeneous nature of dyadic interactions between cows, indicating a non-random movement in the herd. Particularly, proximity loggers provide information about dyadic spatial interactions between animals, which can be used to permanently monitor the social behaviour of dairy cows and estimate spatial occupancy by applying trilateration algorithms.

In addition, automated milking systems collect daily information about individual cows' milk production (e.g., milk yield and somatic cell count). The inclusion of subclinical conditions in mastitis control protocols (i.e., somatic cell count information) in dairy cattle has been one major advance in dairy health. Diseases in dairy cows can lead to decreased milk production, as well as increased use of antibiotics and other treatments, which can contribute to the development of antibiotic-resistant bacteria that can be harmful to humans and the environment. Therefore, the application of preventive measures to reduce the incidence of mastitis in dairy cows will promote the principles of One Health in the dairy industry.

Bearing this in mind, we will explore the relationship between the social networks and area occupancy of dairy cows with the individual somatic cell count data. The results provided by this pilot study will provide a baseline for understanding how the social interactions and proximity between dairy cows could impact their somatic cell count. Based on these findings, we will design a long-term project to unravel the transmission routes of mastitis-causing bacteria within barns and to design prevention and intervention protocols for transmissible diseases in dairy cows.

Contact researcher

Hector Marina, hector.marina@slu.se, tele +46793506609

 

Cattle: Brackish water as drinking water for high-producing dairy cows

Project: January 2024 - May 2024

Due to periodic water scarcity in certain parts of Sweden where cattle production is common, it is necessary to investigate possible alternative drinking water sources for cattle. Results from other studies have shown that ruminants can drink water with some salinity without negative effects. To date, farmers have also been using brackish Baltic Sea water as a source for their grazing cattle, without observing any obvious health issues. This study is needed to investigate the ability of high-producing dairy cows to drink brackish water with a salinity up to 8 g NaCl per litter of water, which corresponds to the salinity of the Baltic Sea in southern Sweden. In this study, 18 cows in Latin-Square design will be offered drinking water with three different salt concentrations, determined based on the results from the pilot study. 

Contact researchers

Anna Jansson, anna.jansson@slu.se, tel.: +4618672106

Sigrid Agenäs, sigrid.agenas@slu.se, tel.: +4618671633

Other participants in the project

Lea Managos, (PhD student, SLU), lea.managos@slu.se, tel.: +46722380077

 

Cattle: CowCalf 2023 spring

Keeping dairy calves with their dams during the milk feeding period in dairy production is a reoccurring subject gaining increasing interest from both farmers and consumers. However, more knowledge is needed on best-management-practice. 

Contact researchers

Sigrid Agenäs, sigrid.agenas@slu.se, tel. +4618671633, +46706973231 Professor at the Department of Animal Nutrition and Management; Management, Ruminants

Hanna Eriksson, hanna.eriksson@slu.se, tel. +4618671949, +46730493911

Claire Wegner (PhD student) claire.wegner@slu.se, tel. +4618672262, +46730293885

Other participants in the project

Gunilla Helmersson (Experiment technician), gunilla.helmersson@slu.se, tel. +4618671605, +46706664379

Cady Wing Yin Chan (student), cyan@stud.slu.se

 

Cattle:  Forest by-products as ruminant feed

This experiment is a part of the FORMAS-funded project Managing forage shortage crises with forest by products. The main objective of the experiment is to evaluate feed intake, digestibility and production in dairy cows if dietary ley silage is partly replaced by either native birch sawdust or by birch sawdust upgraded through a technique known as steam explosion. Steam exploded birch processed by this actual method has in Norwegian laboratory trials reached high digestibility values. This is the first evaluation in a dairy cow experiment. 

Contact researchers

Torsten Eriksson, torsten.eriksson@slu.se, tel., +46738098474, +4618671643

Bengt-Ove Rustas, bengt-ove.rustas@slu.se, tel., +4618671663, +46722446955

Other participants in the project

Tomas Rondahl, Experiment technician.

 

Cattle: Induced lameness in dairy cattle

Lameness is a major welfare issue in dairy cattle, resulting in suffering for the cow as well as economic losses for the farmer. Lameness is often visually assessed at walk and can be difficult to detect at an early stage. The most common reason for lameness is claw disorders, which often occurs in both hindlimbs. When two-limb lame, the cow may try to offload both hindlimbs, potentially resulting in an even more challenging lameness to visually assess than a single-limb lameness. The purpose of this project is to understand how cows move during single- and two-limb low-grade lameness.

By measuring the movement pattern with a portable gait analysis system in the home environment of the cows, and by using advanced camera techniques to register movement patterns in the loose-housing system, we can compare measurement values to identify differences in the movement pattern between sound, single- and multi-limb lame cows. We hope that the results from this project will improve early lameness detection by contributing with new knowledge about lameness

Contact researcher

Katrina Ask, katrina.ask@slu.se, tel. +4618672125

Other participants in the project

Maja Söderlind (PhD student, SLU), maja.soderlind@slu.se, tel. +4618672131

Adrien Kroese (PhD student, SLU), adrien.kroese@slu.se, tel. +4618672199

Niclas Högberg (postdoc, SLU), niclas.hogberg@slu.se, tel. +4618672958

Marc Ahlse (Sony Nordic), marc.ahlse@sony.com 

 

Cattle: Using body language to assess emotional states in dairy cows

Currently it is widely accepted that animals can feel pain and suffer, and methodologies assessing the negative welfare have been developed and extensively studied. One cannot say the same in relation to studies on the positive emotions of animals and their related indicators, which is still a challenge. However, body language (e.g. subtle changes in body posture) has been shown to be a potential indicator of their emotional states. We aim to identify indicators of their emotional states using their body language, firstly mapping their body expressions, behaviour and physiological responses (heart rate) under negative and positive controlled conditions in the tie-stall and secondly using these indicators to study their emotional states when experiencing their routine situations in the loose stall (milking, feeding, social interactions and use of mechanical brushes).

As grooming behaviour seems to be linked with positive reward and wellbeing and mechanical brushes becomes more common in loose housing (and cows use them a lot), we aim to evaluate how this form of self-stimulation correlates with other types of grooming behaviour (self-grooming or social grooming) and how the social ranking of the cows in the group and different types of stressful situations correlates with the brush use (e.g. brushes may serve as a "social buffer" in a stressful environment).

We also aim to assess how the production and health parameters relate to the brush use and dairy cows emotional states. To do this we will use the automatically collected (base) data from each cow as well as regular standardised scoring of cleanliness, lameness, injuries etc. We will also take milk samples for later analysis as the treatments may have short term effect milk composition.

Contact

Linda Keeling

Daiana Oliveira

 

Cattle: Effect of incomplete milking on udder health and milk yield on udder quarter level and milk yield on udder quarter level

With automatic milking systems it can happen that one udder quarter will be incompletely milked. This can be caused by the cow kicking off the milking unit or the robotic arm failing to attach the milking unit at the teats. Since the milking process is fully automated no personal is present to reattach the milking unit/teat cup. The udder quarter where the teat cup has fallen off, or where the attachment of the teat-cups have failed will be incompletely milked until the next milking, unless the cow get milking permission within a short time after completed milking. How frequent incomplete milking is and how it will affect the production capacity and udder health is not fully evaluated. Science based results are required for recommendations whether the omitted milked udder quarter should be milked directly after completed milking or if that udder quarter can wait until the next planned milking event.

Contact

Kerstin Svennersten Sjaunja

Ida Ljunggren

 

Cattle: The role of mast cells in bovine mastitis

Mast cells are tissue-resident pro-inflammatory leukocytes recognized as a part of the innate immune system. Mast cells have been shown to influence the course of bacterial infections yielding different outcomes depending on the severity of infection. In severe infections the mast cell has been shown to have a detrimental effect. In other cases it has a protective function.

Mastitis – inflammation of the mammary tissue – is globally the most common disease amongst dairy cows. All forms of the disease incur economic losses in terms of reduced milk yields and treatment costs. The clinical form of the disease in particular impinges the health and welfare of the cow. Mastitis is often the result of a bacterial infection, commonly involving species such as Escherichia coli and Staphylococcus aureus. Our current knowledge of the immunological aspect of mastitis is limited and the putative role of mast cells in this type of disease has not previously been investigated. The goal of this experiment is to determine whether or not the mast cell is involved in the immune reaction to bacterial bovine mastitis. We expect that a deeper understanding of the mast cells role in bacterial mastitis could lead to improvements in diagnostics and treatment. For example, the presence of mast cell inflammatory mediators in the blood of a mastitis afflicted cow could be used as a diagnostic criterion. Similarly, drugs used to counteract the effect of harmful mast cell associated mediators could be brought into use as a mastitis treatment. Alternatively, mast cell components shown to have a protective effect could be used in treatment of mastitis.

Contact

Emma Ternman, emma.ternman@slu.se, +46 (0)18-67 16 18

 

Cattle: Physiological effects of dairy cow´s usage of mechanical brushes: The effect on plasma oxytocin and plasma cortisol levels, behaviour, immunology, heart rate and heart rate variability

Good welfare can be seen as the possibility to experience positive affective states and not only the lack of poor welfare. Interest in investigating positive emotions in animals has grown lately. There is a need to identify reliable and feasible indicators of positive emotions in animals and grooming behaviour has been indicated as a potential candidate. As the supply of mechanical brushes for dairy cows in loose housing systems is increasing combined with the fact that they are highly used by the majority of the cows, mechanical brush usage become a key component of grooming behaviour to be addressed on farm level.

In this project we will investigate how the use of mechanical brushes interacts with stress at an individual level. More specifically, we plan to assess if the use of mechanical brushes has a buffering effect toward stress and also if its usage can have a calming effect after being exposed to a stressor. These emotional manipulations will be assessed by behavioural, physiological and immunological parameters. Blood samples and heart rate measurements will be taken before, during and after the brush use, in an experimental design testing the exposure to a stressor before and after the brush use.

Contact

Emma Ternman, emma.ternman@slu.se, +46 (0)18-67 16 18

 

Cattle: Dark vision in dairy calves

According to the Swedish animal welfare legislation lighting during darkness hours is required, but the legislation does not specify minimum or maximum light intensity. Calves and growing cattle, just as lactating animals, benefit from long days with relatively high light intensity, the recommendation is 16 hours light with a minimum of 180 lux. This will enhance growth rate and milk production but in our previous studies we have seen that cows’ activity is changed when exposed to 24 hours of light and that they seem to rest less. For this reason in addition to the environmental aspect of reduced energy consumption, we believe it is important to lower the light intensity during part of the 24-hour period.

Our previous studies have provided us with understanding of the effect of different light intensities and light colours on cow behaviour, we know that they can move around without problem in low light intensities and low light intensities do not reduce their activity at night. However, it has still not been studied how calves react on darkness and this project therefore aims to study whether the calves’ movement pattern change with different light intensities.

Contact

Emma Ternman, emma.ternman@slu.se, +46 (0)18-67 16 18

 

Cattle: Total mixed ration - competitive feeding system on organic farms with automatic milking?

Farms with automatic milking (AM) have steadily increased in Sweden over the last years and the organic farmers are no exception in this development. One of the most important factors that contribute to maintaining a high production level in AM is well-functioning cow traffic and frequent visits to the milking unit. Low milking frequencies may affect udder health negatively and a common opinion is that it also results in lower milk yield. However, there are studies showing that the relationships are unclear and the causes multifactorial.

In order to achieve a high production level, farmers are often advised not to feed silage or a mixed ration of high nutritional value at the feed bunk, because it is said to lower the cows’ motivation to visit the milking unit. It is not unusual that straw is mixed into the feed in order to reduce the energy content of the mix. Nevertheless, it must be considered a limitation for the production to not use high nutritional feeds when most farmers’ strive to harvest the crop at the optimum stage of development. Scientific literature is scarce on how the feed concentration in a total mixed ration affects milking frequencies and milk yield in AM systems. Hence, the aim of this project is to evaluate these variables when the cows are fed mixed ration versus fed silage and concentrate separately in three different cow traffic systems.

 

Cattle: Do milk fat have an inhibiting effect on milk synthesis? If so - how could this be used in practice?

2015-11-09 – 2015-12-22

The prerequisite for sustainable dairy production is persistent lactation and high yield. The trend in dairy production is fewer but bigger herds with increasing level of automation, like automatic milking (AM). To increase the efficiency in AM, automatic cluster take off can be done at high milk flow levels and with reduced pre-stimulation, which might have negative impact on udder emptying. In AM each udder quarter is milked separately. However, the knowledge about optimal use of AM, for instance with quarter milking and how the routines influence udder emptying and production, is insufficient. The aim with the project is to evaluate how pre-stimulation and take off level, in combination, shall be practiced for efficient milking in sustainable production. With this new knowledge routines can be developed for better use of AM, optimal milk extraction and better economy.

 

Contact

Emma Ternman, Emma.Ternman@slu.se, +46 (0)18-67 1618

Sigrid Agenäs, Sigrid.Agenas@slu.se, +46 (0)18-67 1633

Christine Hultén, cehn0001@stud.slu.se, +46 (0)76 868 49 99

Maria Tegevall, mall0002@stud.slu.se, +46 (0)73504 41 20

 

Cattle: Fortune part 2: Change-over trial with large roughage allowances and byproduct based concentrates

Dairy cows can as all ruminants transform fibrous feed non-edible for humans (e.g. forage and different by-products) into high valuable protein as milk and meat. Today cows are fed substantial amounts of cereal grain and pulse, which instead could be eaten by humans directly. The increasing global demand for human food is contributing to the growing competition of grain cereals and protein-rich products as e.g. soy between humans and production animals and it is assumed to increase. When cereals and other crop are processed into human food or bio fule, then also by-products suitable for dairy cow feed are produced.

The aim with the study is to investigate the effects of a diet completely based on large amount of forage and by-products have on dairy cows production. We expect that these systems will be contribute to a more sustainable milk production, both economically and environmentally.

Contact

Johanna Karlsson

johanna.karlsson@slu.se

Telefon: 018-671256, 072-3410634

 

Kjell Holtenius

kjell.holtenius@slu.se

018-671629

 

Rolf Spörndly

rolf.sporndly@slu.se

018-671992, 070-5672189

 

Mikaela Patel

mikaela.patel@slu.se

018-671013

 

Filippa Larsson

fila0001@stud.slu.se

070-0927499

 

Cattle: Pair keeping of calves in calf huts outdoors – impact on growth and suckling behaviour

The use of calf huts outdoors for keeping calves has expanded in recent years and so has the interest in how to increace weight gain and maintain a good health in this environmeant. Today most calves are held separately in the huts even though it is allowed with pair holding. Some of the reasons for this is to maintain a low disease flow between the calves, a good feed intake and also to reduce the risk of the calves suckling on each other. Feeding of milk is usually done with teat buckets two times per day but the common feeding routines do not always satisfy calves need for suckling, with calves showing redirected suckling behaviours as a consequence.

In this study we will look at how weight gain, health and redirected suckling behaviours are affected by keeping calves in pairs versus keeping single calves in calf huts. We are interested in if a good feeding routine for milk in combination with keeping calves in pairs will increase growth and decrease the occurrence of redirected suckling behaviours. Factors will be assessed with behavioural and physiological parameters. Weight measurements will be done when the calves are moved to the calf huts, during the trial and at weaning. Behavioural observations will be done continuously during the trial.

Contact

Lena Lidfors

Phone: +46 (0)51167215; 0703468032

Therese Alvegard

Phone: +46 (0)767741614

Cattle: Forage based diet to 100 dairy cows in early lactation

Cows are forage eaters, but are today fed with substantial amounts of concentrate based on cereals and pulse (beans etc). Cereals and pulse could instead feed humans directly. The ability to consume forage varies a lot between individual cows. Some of that variation in forage consumption can be explained by genetics.

The purpose of this study is to identify the cows that are best and worse regarding forage consumption, so that we can follow these extremes more closely during next full lactation. This so that we in the future can breed on dairy cows that have a high ability to consume forage which would lead to a lower need of using human-edibles as feed for ruminants at the same time as maintaining high milk yields. This would both increase profitability and decrease the environmental impact of dairy production.

Contact

Johanna Karlsson

johanna.karlsson@slu.se

0723410634

Mikaela Patel

mikaela.patel@slu.se

018-671013

Kjell Holteinus

kjell.holtenius@slu.se

018-671629

Cattle: Prolific – multidisciplinary study for robust and sustainable improvement of dairy cow fertility

Metabolism and reproductive disorders are gaining importance in parallel with intensifying milk production, in high-producing dairy cows. Genetic progress in conjunction with diet and good herd management helped to increase milk production. It is noteworthy that during the last five decades the number of farms and cows in Sweden has decreased while milk production has actually increased. Looking at the exact numbers and figures we can see that the average yearly milk yield for Swedish red in 1965 was 4833kg while the average milk yield in 2011 was more than 9000kg.

Comparing milk production during the last 50 years with the calving interval you notice that while milk production is getting higher calving intervals are getting longer. It is crucial in order to have a stable and high herd fertility to have an optimal calving interval resulting in fewer inseminations and lower risk for the animal to be culled. During early lactation high producing milk cows are exposed to negative energy balance as the intake food cannot provide the necessary amount of the needed energy which is required for milk production and body needs. The aim of our study is to identify and improve breeding strategies and sustainable management practices in order to optimize cow fertility and robustness.

Contact

Theodoros Ntallaris

Patrice Humblot

Renée Båge

Britt Berglund

Cattle: Estimation of energy balance in dairy cows using an automatic body condition scoring camera

The energy balance (EB) of dairy cows has impact on animal health, fertility and feed economy. Cows mobilise body reserves in early lactation to support the energy demand from the increasing milk production. Cows that come into critically low EB are at higher risk for health problems and poor fertility. This leads to increasing costs for the farmer in terms of higher culling rates, lower production etc. Efficient routines for early detection of cows with critically low EB are lacking today. Traditionally, manual body condition scoring (BCS) is used for finding cows at high risk but this method is subjective and labor-intensive. With the use of new camera based technique it is now possible to automatically monitor BCS in an objective way which create new possibilities to detect changes in BCS related to energy balance.

The aim of this study is to develop mathematical models to estimate the EB of dairy cows with data from an automatic BCS system. In the study we will gather information from the cows feed consumption, milk production etc. to calculate the EB. Models to estimate the EB with data from the BCS system will be developed by different calculation methods.

Contact

Bengt-Ove Rustas, bengt-ove.rustas@slu.se, +46 (0)18-67 16 63, +46 (0)72-244 69 55

Majbritt Felleki, majbritt.felleki@slu.se, +46 (0)18-67 26 53, +46 (0)72-549 58 26

Other participants in the project

Britta Skottheim, bask0001@stud.slu.se, +46 (0)70-344 53 33

Cattle: Total mixed ration – competitive feeding system on organic farms with automatic milking?

Part 3 – "Milk first" cow traffic

Farms with automatic milking (AM) have steadily increased in Sweden over the last years and the organic farmers are no exception in this development. One of the most important factors that contribute to maintaining a high production level in AM is well-functioning cow traffic and frequent visits to the milking unit. Low milking frequencies may affect udder health negatively and a common opinion is that it also results in lower milk yield. However, there are studies showing that the relationships are unclear and the causes multifactorial. In order to achieve a high production level, farmers are often advised not to feed silage or a mixed ration of high nutritional value at the feed bunk, because it is said to lower the cows' motivation to visit the milking unit. It is not unusual that straw is mixed into the feed in order to reduce the energy content of the mix. Nevertheless, it must be considered a limitation for the production to not use high nutritional feeds when most farmers' strive to harvest the crop at the optimum stage of development. Scientific literature is scarce on how the feed concentration in a total mixed ration affects milking frequencies and milk yield in AM systems. Hence, the aim of this project is to evaluate these variables when the cows are fed mixed ration versus fed silage and concentrate separately in three different cow traffic systems.

Contact

Mikaela Patel

mikaela.patel@slu.se

018-671013

Eva Spörndly

eva.sporndly@slu.se

018-671632

Cattle: Oesophageal Tube (OT), suckling and bottle colostrum feeding

New born calves have insufficient immunity to fight disease and rely on the transfer of passive immunity, via ingestion of maternal immunoglobulins (IG) present in the colostrum soon after birth, to fight infections. The time of first colostrum feeding, amount of IGs in colostrum and the volume of colostrum consumed all influence the transfer of passive immunity. For these reasons, it is becoming a common practice in dairy farms (especially in North America) to feed colostrum via oesophageal tube (OT) as a way to ensure a good transfer of passive immunity in dairy calves, and now this practice is being promoted in Sweden.

However, the effects of OT feeding on transfer of passive immunity and the long term consequences for health and welfare of the calves have not been studied in detail and in an holistic way that assess not only immunity of the calves but also their welfare. For this reason, the aim of this study is to investigate the effects of OT vs suckling vs bottle feeding  at birth on the transfer of passive immunity, physiological, endocrine and behavioural response to the three feeding methods, growth, health and sleep patterns (as a welfare measure) in dairy calves. Another aim is to study the development of gut microbiota, over the first 14 days of calf life, in relation to the feeding treatments.

Contact

Carlos E. Hernandez

Bengt-Ove Rustas

Cattle: Osmolality study; Evaluation of animal welfare indicators for dairy cows, with regards to thermic comfort and dehydration

This study aims to develop and produce methods to assess thermal comfort and the degree of dehydration in individual cows, ie, the degree to which a cow ingests enough water for their milk and other bodily functions. The studied methods will be evaluated to see if they can be used in the official control.

Dairy cows need to drink a lot of water for their milk, moreover, they have a great need to get enough water to compensate the second fluid losses (urine, faeces and evaporation). The official animal welfare control controls that feeding and water systems are designed, dimensioned and positioned so as to allow a peaceful and natural intake of food and water and that the requirements for access to water and water quality are met. Today there is no reliable method to determine if the animals get enough water.

The following questions will be answered:

1) Can measurements of skin temperature, fur moisture, respiratory frequency, or shivering be used as animal-based indicators of deviations from animal welfare?

2) Could individual cow milk osmolality be used as an animal-based indicator of dehydration as a complement to the resource-based measurement to assess the degree of dehydration?

3) Can osmolality and/or urea in the urine detect if the cow is dehydrated?

Contact

Birgitta Staaf Larsson

Birgitta.Staaf.Larsson@slu.se

+46 (0) 18-67 21 57

Cattle: Buffering salts for dairy cows

Dairy cows produce large amounts of organic acids during fermentation of feed in the rumen. As a result rumen pH varies over time with a decreasing trend from the morning feeding and throughout the day and an increase during the night, when intake declines and rumination dominates. A low rumen pH might lead to depressed digestion and a condition called sub-acute rumen acidosis (SARA). SARA is associated with diseases, e.g. lameness, and depressed feed intake causing farmers considerable economic losses. A way to prevent low rumen pH is to add buffering salts to the cow diet. Sodium bicarbonate and calcium carbonate have traditionally been used as buffers but the effect on rumen pH has been variable in controlled studies. Calcified seaweed consists of the skeletal remains of dead algea that produce calcium carbonate. There are indications that calcified seaweed has a greater potential then traditional buffer salts in preventing low rumen pH. However, there are few evaluations on producing dairy cows and no one has looked at the effect on digestibility, the key determinant for feed utilization. The aim of this study is to evaluate the effect of dietary buffering agents fed to dairy cows on rumen pH, digestion and milk production.

Contact

Bengt-Ove Rustas, Bengt-Ove.Rustas@slu.se, +46 18-67 16 63

Cattle: The role of mast cells in bovine mastitis

Mast cells are tissue-resident pro-inflammatory leukocytes recognized as a part of the innate immune system. Mast cells have been shown to influence the course of bacterial infections yielding different outcomes depending on the severity of infection. In severe infections the mast cell has been shown to have a detrimental effect. In other cases it has a protective function. Mastitis – inflammation of the mammary tissue – is globally the most common disease amongst dairy cows. All forms of the disease incur economic losses in terms of reduced milk yields and treatment costs. The clinical form of the disease in particular impinges the health and welfare of the cow. Mastitis is often the result of a bacterial infection, commonly involving species such as Escherichia coli and Staphylococcus aureus. Our current knowledge of the immunological aspect of mastitis is limited and the putative role of mast cells in this type of disease has not previously been investigated. The goal of this experiment is to determine whether or not the mast cell is involved in the immune reaction to bacterial bovine mastitis. We expect that a deeper understanding of the mast cells role in bacterial mastitis could lead to improvements in diagnostics and treatment.

Contact

Gunnar Pejler (supervisor), gunnar.pejler@slu.se, +46 (0)18 - 471 45 71                      

Carl-Fredrik Johnzon (PhD student), carl.fredrik.johnzon@slu.se, +46 (0)18 – 67 21 50

Other participants in the project

Josef Dahlberg (sampling),  josef.dahlberg@slu.se, +46 (0)18 – 67 16 86

Cattle: Evaluation of the marker method for measuring feed passage rate

Project starts: 18th of december, 2017

The purpose of this study is to evaluate the marker method for measuring feed passage rate. The evaluation will be based on a comparison of two methods; marker in feed and emptying rumen on four fistulated cows. The overall purpose of this study is to reduce the use of human edible food such as wheat, oats and soya as feed for cows. Today, cows in Sweden are often fed with 50% concentrates (cereals, beans, peas, etc.). We want to reduce the grain based feed by feeding a lot of rough fodder such as silage of grass and clover and small amounts of feed based by-products, focusing on maintaining a high milk production. We also aim to breed for cows that are better adapted to eat a lot of coarse fodder and which at the same time both milk well and feel good. Before we can breed cows with better feed utilization, we want to find out what different parameters affect and influence to reduce the risk of losing efficiency in milk production.

Contact

Rebecca Danielsson, rebecca.danielsson@slu.se phone: +46 (0)18 67 16 28

Other participants in the project

Cecilia Kronqvist, cecilia.kronqvist@slu.se

Maria Åkerlind, maria.akerlind@slu.se

Maria Eklund, student, mand006@stud.slu.se

Cattle: Free cow traffic in an automatic milking rotary parlour (DeLaval AMR)

Project starts 16th of January, 2018 - 5th of June, 2018

Free cow traffic and automatic milking have been applied in conventional milk production with automatic milking stations (AMS) in Sweden for almost 20 years. By automating a milking rotary (AMR), DeLaval has scaled up the automatic milking to fit herds of 500-700 cows. There are a dozen of AMR in the world, but only Lövsta is built to study how this system works with free traffic in in-door environment. From facilities in eg Tasmania, we know that free cow traffic works under grazing conditions. The aim of the project is to study the behavior of animals, production aspects, technical solutions, the operation of traffic systems and the work load of the staff in a series of intensive studies, simulating free traffic in a larger herd, using 120 cows and three available milking periods (windows) per day.

Contact

Jan Olofsson, jan.olofsson@slu.se, Phone: +46 (0)18-67 16 36, +46 70-371 4406

Other participants in the project

Gunilla Helmersson, trial engineer, phone: +46 70-666 4379

Elin Rarcovich, student

Ulrica Robertsson, student

 

Cattel: Bovine RS virus

2016-01-01 – 2018-02-28

Bovine respiratory syncytial virus (BRSV) is a common cause of respiratory disease in cattle. This virus spreads rapidly between herds and circulates commonly in fattening units in which calves are commingled from several herds. The clinical signs of BRSV are characterized by fever, rapid or abnormal breathing, serous nasal secretions, cough and sometimes subcutaneous emphysema (air

under skin) and anoxia (lack of oxygen) leading to death. The infection is commonly transient but bacteria often grow in damaged lung tissue and these secondary infections are treated with antibiotics.

Our hypothesis is that subclinically infected cows and/or young stock play an important role in the spread of BRSV (besides calves), as is the case for human RSV. Partially immune children and adults spread virus to infants, sometimes without showing clinical signs.

The aim of the study, which constitutes a part of an EU-project (H2020 633184-2, SAPHIR), is to generate knowledge about the immunity against BRSV. Through better understanding we might in the future be able to identify age categories of animals that should be vaccinated in order to stop virus spread within and between herds. This will concern herds in which safe biosecurity measures cannot be applied, until the risk for virus introduction has been reduced. Immune parameters in nasal secretions, tears, salivia and blood will be studied repeatedly from the same individual animals in several herds during two years. Immune cells from the same individuals of different age will be used for studies of immune stimulating agens (adjuvants), in vitro, to contribute to fundamental knowledge about the development of immunity, as well as for the development of age-adopted vaccines. To isolate live virus, a bronchoalveolar lavage will be performed on a few individuals upon diagnosed BRSV infection. Costs and production losses and the kinetics of virus shedding as well as genetic factors will be studied during outbreaks.

Contact

Jean-Francois Valarcher, Sara Hägglund E-post: jean-francois.valarcher@slu.se, sara.hagglund@slu.se

 

Cattle: Roughage intake ability during a full lactation

Climate change, disturbed nitrogen cycles and loss of biodiversity are among the greatest threats for humanity (Rockström et al., 2009). Another severe challenge is to be able to provide food for everyone in the future when the world population is rapidly increasing while we should not increase the area of arable land (FAO, 2009).  We aim at lowering the negative environmental effects of milk production and at the same time increase its positive effects. By feeding more forage and excluding human edible products as cereal grain and beans from the cows diet the net food production can increase (Ertl et al., 2016) at the same time as ecosystem services as carbon sequensation and increased biodiversity is promoted (Knudsen & Hermansen, 2015). The cows forage intake capacity and production of the greenhouse gas methane varies a lot between individuals. The variation depends on a number of factors, as the cows genes, rumen microbiota and passage rate. The aim is to better understand the mechanisms regulating forage intake capacity and methane production, and investigate if it is possible to breed for cows with high forage intake capacity and low methane production. We will also study if it is possible to decrease the nutrient leakage from milk production by decreasing total crude protein (nitrogen) content in the cow diet and instead add rumen protected amino acids in the small by-product based concentrate ration.

Contact

Johanna Karlsson,Johanna.Karlsson@slu.se, +46 (0)723410634

 

Cattle: Field experiments 2017

Grazing systems for dairy cattle has the potential to be resource efficient for the farmer. However, increased herd sizes can cause major problems with trampling damages on soil leading to clawproblems and dirty udders, which costs working time for cleaning and risk of deteriorated animal health. Farmers ask for durable pasture swards and cost efficient investments. The aim of the project is to develop technical and agronomic solutions for long-term pasture management with a large dairy herd. The objectives are: 1) evaluate four seed mixtures with regard to production and resilience to trampling by measuring vegetation cover, botanical composition, production potential and feed value. 2) evaluate two materials used to protect areas exposed to a high degree of trampling in relation to investment costs. This is a continuation of the field experiments that started 2012.

Contact

Eva Salomon (JTI), eva.salomon@jti.se, Telephone: +46 (0)10-516 69 61, +46 (0)70-595 00 23

Other participants in the project

Martin Sundberg (Part 2), martin.sundberg@jti.se, Telepone: +46 (0)10-516 69 24, Mobile +46 (0)70-370 86 31

Nilla Nilsdotter-Linde (Part 1), nilla.nilsdotter-linde@slu.se, Telephone: +46 (0)18 67 14 31, Mobile: +46 (0)70 662 74 05

Marianne Tersmeden (Part 1 and Part 2), marianne.tersmeden@JTI.se, Mobile: +46 (0)70-952 82 73

Eva Spörndly (Part 1), eva.sporndly@slu.se,Telephone: +46 (0)18 67 16 32, Mobile +46 (0)70-560 979

 

Cattle: Total mixed ration (TMR) - does it improve animal welfare?

Total mixed ration (TMR) feeding is used to a large extent in the dairy production. It is beneficial for the cow as the forage and the concentrate is mixed together, resulting in a more stable rumen environment compared to when concentrate is fed separately. However, the cows might sort the diet, resulting in some cows consuming high levels of starch-rich concentrate and other cows experiencing difficulties with fulfilling their energy requirements with the feed that is left. The aim of this project is to decrease sorting of the diet by prolonged mixing and addition of water, and to study how this will affect the behavior, intake, production, and rumen health of the cows.

Contact

Mikaela Patel, mikaela.patel@slu.se, phone: +46 (0)18 - 67 10 13

Researcher at the Department of Animal Nutrition and Management

Cecilia Kronqvist, cecilia.kronqvist@slu.se, phone: +46 (0)18 - 67 16 54

Researcher at the Department of Animal Nutrition and Management

 

Cattle: Pair keeping of calves in calf huts outdoors – impact on growth and play behaviour (degree project)

Calves are commonly kept individually in outdoor hutches during the first period in their life. It is beneficial both from a financial and animal welfare point of view to optimise this type of housing. Studies have shown that pair-housing calves may affect the calves' behaviour, i.a. social behaviour and play behaviour. It has also been shown that calves have better stress coping abilities if they have been pair-housed. Other studies, focusing on feed consumption and growth have found that pair-housed calves consume more feed and had a less impaired growth rate at weaning than individually housed calves. However, no differences in health parameters have been found between pair-housed and individually housed calves. The objective of this study is to compare play and social behaviour on an arena, as well as growth and milk and concentrate consumption between pair-housed and individually housed dairy calves outdoors. Health will also be considered. This is to test the hypothesis that pair-housed calves have unchanged or improved growth rate, better social skills and unchanged health compared to individually housed calves. Because play is considered to function as an animal welfare indicator I will also examine whether pair-housing affects welfare by observing play behaviour on an arena.

Contact

Lena Lidfors, lena.lidfors@slu.se

Other participants in the project

Namn: Ellika Waldau (student), elau0001@stud.slu.se

 

Cattle: Effects of LED light on activity and production in dairy cows

During the last ten years LED-lights have become available for animal facilities and they are now a common choice when light fixtures are replaced in dairy barns. With LED technology lights with specific wavelengths can be tailor made. This has been well developed for use in greenhouses but there is very limited knowledge about the most suitable wavelengths for animals. The aim of the project is to study effects of LED-light on milk production and activity in dairy cows.

The main hypothesis is that LED light allows maintained cow activity and milk production with less energy used for illumination, and that LED-light makes it possible to apply a dark period during the natural night without decreased milk yield. Two or three trials will be conducted in a light lab at Lövsta, in order to identify suitable wavelengths and light intensities that will be validated in field tests at commercial farms in the finishing phase of the project. The project should result in recommendations for LED-light in dairy barn for decreased energy use at maintained or higher milk production.

Contact researchers

Sofia Lindkvist, sofia.lindkvist@slu.se, tel., +46 (0)18 67 25 82

Björn Ekesten, bjorn.ekesten@slu.se, tel., +46 (0)18 67 18 14

Sigrid Agenäs, sigrid.agenas@slu.se, tel., +46 (0)18 67 16 33 Professor at the Department of Animal Nutrition and Management; Management,Ruminants

 

Cattle: CowCalf 2019

Keeping dairy calves with their dams during the milk feeding period in dairy production is a reoccurring subject gaining increasing interest from both farmers and consumers. However, more knowledge is needed on best-management-practice. One aim of the study starting summer 2019 is to develop a management system where the cow and calf are kept together, on pasture and in the VMS-free stall during the first 4-5 months of lactation.

Contact researchers

Sigrid Agenäs, sigrid.agenas@slu.se, tel. +46 (0)18 67 16 33, +46 (0)70 556 72 03. Professor at the Department of Animal Nutrition and Management; Management, Ruminants

Hanna Eriksson, hanna.eriksson@slu.se, tel. +46 (0)70 206 92 67.  Department of Animal Nutrition and Management; Management Ruminants                                     

Daiana De Oliveira, daiana.oliveira@slu.se, tel. +46 (0)18 67 17 30, 076 903 06 54. Department of Animal Environment and Health; Section of Ethology and Animal Welfare

Other participants in the project

Experiment technician: Gunilla Helmersson, gunilla.helmersson@slu.se, tel. +46 (018) 67 16 05, +46 (0)70 666 43 79

Student on placement from France: Henri Duchaux, duchaux_henri@orange.fr, tel. +33-78-697 65 85 

Degree project student: Josefin Molin Björklund, jomo0003@stud.slu.se 

 

Cattle: CowCalf 2020 spring

Keeping dairy calves with their dams during the milk feeding period in dairy production is a reoccurring subject gaining increasing interest from both farmers and consumers. However, more knowledge is needed on best-management-practice. One aim of the study starting spring 2020 is to collect more detailed health data from both cows and calves.

Contact researchers

Sigrid Agenäs, sigrid.agenas@slu.se, tel. +46 (0)18 67 16 33. Professor at the Department of Animal Nutrition and Management; Management, Ruminants

Hanna Eriksson, hanna.eriksson@slu.se, Department of Animal Nutrition and Management; Management Ruminants                                     

Daiana De Oliveira, daiana.oliveira@slu.se, tel. +46 (0)18 67 17 30. Department of Animal Environment and Health; Section of Ethology and Animal Welfare

Josef Dahlberg, josef.dahlberg@slu.se, tel. +4618671686, Department of Animal Nutrition and Management; Management Ruminants    

Other participants in the project

Experiment technician: Gunilla Helmersson, gunilla.helmersson@slu.se, tel. +46 (018) 67 16 05

Degree project students:

Johanna Lilja, Carina Tufvesson, Josefin Molin Björklund, Elin Svensson.

 

Cattle: Processed silage - the "Extruder project"

Jan - april, 2020

The purpose of the project is to increase forage consumption in dairy cows, thereby reducing the need for purchased concentrate feed. Mechanical processing of forage reduces particle size and breaks up plant structures. In the project grass silage will be processed by extrusion, a technique used for pretreatment of biomaterial at biogas plants. The expected result of the processing is increased forage intake and improved utilization of protein through faster rumen passage. The consequence is expected to be a reduced need for purchased protein concentrates.

Contact researchers

Bengt-Ove Rustas, bengt-ove.rustas@slu.se, tele +4618671663

Other participants in the project

Research technician: Rainer Nylund, rainer.nylund@slu.se, tele: +4618671635

 

Cattle: CowCalf 2020 autumn

Keeping dairy calves with their dams during the milk feeding period in dairy production is a reoccurring subject gaining increasing interest from both farmers and consumers. However, more knowledge is needed on best-management-practice. One aim of the study starting autumn 2020 is to collect more detailed health data from both cows and calves.

Contact researchers

Sigrid Agenäs, sigrid.agenas@slu.se, tel. +4618671633. Professor at the Department of Animal Nutrition and Management; Management, Ruminants

Hanna Eriksson, hanna.eriksson@slu.se, tel. +46730493911 Department of Animal Nutrition and Management; Management Ruminants

Other participants in the project

Experiment technician: Gunilla Helmersson, gunilla.helmersson@slu.se, tel. +4618671605

Degree project students:

Rebecka Lindqvist, Erik Backman, Rebekka Bakke

 

Cattle: Milk urea concentration

The experiment is part of a larger project for facilitating a transition to more homegrown protein feeds in dairy herds. The objective of this certain experiment is to study the changes in milk urea concentration on short term and intermediate time basis when disturbances in protein feeding are simulated. Milk urea is a marker that reflects the protein status of the dairy cow. The experiment should provide guidelines that indicates which magnitude of change in milk urea concentration that indicates error in the concentrate processing chain, requiring action.

Contact researchers

Torsten Eriksson, torsten.eriksson@slu.se, +46 18 67 16 43. Department of Animal Nutrition and Management

Other participants in the project

Rainer Nylund, rainer.nylund@slu.se, +46 18 67 16 35.Department of Animal Nutrition and Management.

 

Cattle: The body language of dairy calves: Investigating emotions through ear, neck and tail posture

Degree project

Though much progress has recently been made, information regarding the identification and understanding of positive emotions in animals is still lacking. While the avoidance of negative emotions in animals is important for a high quality of welfare, ensuring the presence of positive emotions is equally important. Recent research has begun to explore interactions between positive emotions and various physical observations of dairy cows, such as ear posture.

The aim of this study is to further develop this research through analyzing the relationship between ear, tail and neck postures of dairy cows and positive/negative emotion. Specific predictions regarding links between body posture and emotional states will be made based on previous research.

Contact researcher

Linda Keeling, linda.keeling@slu.se, +46(0)18  67 16 22. Department of Animal Environment and Health

Other participants in the project

Kirste Colleen Mccrea, kimc0001@stud.slu.se,  +46 (0)727 14 28 44

Yezica Norling, Yezica.Norling@slu.se, +46 (0)18 67 21 15

Daiana de Oliveira, Daiana.Oliveira@slu.se, 018-67 17 30

 

Cattle: Processed silage - the "Extruder project"

Jan - april, 2020

The purpose of the project is to increase forage consumption in dairy cows, thereby reducing the need for purchased concentrate feed. Mechanical processing of forage reduces particle size and breaks up plant structures. In the project grass silage will be processed by extrusion, a technique used for pretreatment of biomaterial at biogas plants. The expected result of the processing is increased forage intake and improved utilization of protein through faster rumen passage. The consequence is expected to be a reduced need for purchased protein concentrates.

Contact researchers

Bengt-Ove Rustas, bengt-ove.rustas@slu.se, tele +4618671663

Other participants in the project

Research technician: Rainer Nylund, rainer.nylund@slu.se, tele: +4618671635

 

Cattle: CowCalf 2021 spring

Keeping dairy calves with their dams during the milk feeding period in dairy production is a reoccurring subject gaining increasing interest from both farmers and consumers. However, more knowledge is needed on best-management-practice. One aim of the study starting spring 2021 is to study the difference between weaning the calves at 4 and 8 months of age.

Contact researchers

Sigrid Agenäs, sigrid.agenas@slu.se, tel. +4618671633, +46705567203 Professor at the Department of Animal Nutrition and Management; Management, Ruminants

Other participants in the project

Experiment technician: Gunilla Helmersson, gunilla.helmersson@slu.se, tel. +4618671605

Degree project students and others.

 

Cattle: Changes in the rumen’s fiber degrading enzyme system when forest by-products are included in the ration.

The main objective of this experiment is to study changes in the rumen’s fiber degrading enzyme system when forest by-products are included in the ration. In addition, standard measurements of intake pattern, digestibility and general rumen metabolism will be performed. The objective of the entire project is to evaluate forest by-products (wood chips and bark, unprocessed or upgraded), as a roughage extender for dairy cows during shortage episodes.

Processed forest by-products were during World War 2 extensively fed to cattle and horses in Sweden. Feeding trials have since then occasionally been performed internationally, most recent as a pilot experiment at NMBU in Norway 2018 where dairy cows quickly adapted to eating 6 kg dry matter aspen sawdust/day. Aspen is the tree species that has displayed the highest digestibility in vitro and when fed to ruminants.

Contact researchers

Torsten Eriksson, torsten.eriksson@slu.se, tel. +4618671643

Bengt-Ove Rustas, bengt-ove.rustas@slu.se, tel. +4618671663

 

Cattle: An obstacle course study - the acitivity of dairy cows during movement in different light environments

During the dark hours, the activity of dairy cows is lower than during daytime. Less activity during night-time could affect the productivity in automatic milking systems. There is a general perception that cows are more likely to suffer from teat injuries in darkness due to stress and fear of darkness. In 2013, an obstacle course study was conducted at Lövsta where the cows’ activity, heart and respiratory rate were registered in four different light intensities and with or without red light. Today, it is possible to measure light with greater precision and to use LED lamps with their own control center to be able to create different light environments. The cows will be trained in the obstacle course in full daylight and then test the obstacle course in different light environments; white, red and blue light. The purpose of the obstacle course study is to investigate the activity of the cows during movement in different light environments.

Contact researcher

Sofia Lindkvist sofia.lindkvist@slu.se tele +4618672582

Department of Animal Nutrition and Management, Management Ruminants

 

Cattle: Orthopaedic pain in cattle - lameness and pain

Orthopaedic pain, with lameness as the main symptom, is one of the biggest welfare issues in dairy cows around the world, leading to a decrease in milk production, feed intake and fertility. To minimize the pain and improve the prognosis, it is important to detect lameness at an early stage and initiate correct treatment. The purpose of this project is to study the movement patterns in lame cows and describe their pain behaviour and pain face. We measure movement symmetry with small accelerometers mounted on the body, and compare the results with results from healthy cows. Pain behaviour and pain face are recorded on video, described for cows with lameness, and compared to behaviours and facial expressions in healthy cows. With detailed knowledge of how cows adapt their movements during lameness and how they express orthopaedic pain, we hope to be able to identify lameness earlier and assess pain in a more precise way thereby increasing the welfare in dairy cattle.

Contact researchers

Katarina Ask (PhD student, SLU), katarina.ask@slu.se, tel.: +46 (0)18 67 21 25

Marie Rhodin, marie.rohdin@slu.se, tel.: +46 (0)18  67 21 94

Christer Bergsten, christer.bergsten@slu.se, tel.: +46 (0)70 399 33 29

Pia Haubro Andersen, pia.haubro.andersen@slu.se, tel.: +45 313 181 47

Elin Hernlund, elin.hernlund@slu.se, tel.: +46 (0)18 67 21 42

Marij Tijssen (PhD student, Utrecht University), m.tijssen@uu.se, tel.: +31 654 788 348

 

Cattle: Milk fatty acids – tools to identify cows with increased risk för metabolic diseases and fertility disturbances

The aim of this project is to develop precision tools based on specific milk fatty acids in order to identify cows that have an increased risk to develop metabolic diseases and fertility disturbances. The study will be performed at SLU´s dairy research farms at Lövsta and Röbäcksdalen. We will determine key fatty acids in milk, hormones and metabolites in blood reflecting metabolism and fertility. The goal is to pinpoint milk fatty acids that reflect metabolic and reproductive disturbances in cows. A second study will be performed in 20 large commercial dairy herds. We will have access to milk fatty acid profiles, yield, veterinary treatment and fertility recordings. The ultimate goal of the project is that the farmers should have simple access to tools that will support actions both on individual- and herd level that contribute to sustainable milk production.

Contact researcher

Kjell Holtenius, kjell.holtenius@slu.se, tel. +4618671629, +46701721873

Other participants in the project

Gunilla Helmersson, gunilla.helmersson@slu.se, tel. +4618671605, +46706664379

 

Cattle: Probiotics to dairy cows

Probiotics are feed supplements containing living microorganisms that are considered to benefit the health of the recipient animal. Microbial supplements have been used in cattle for at least 30 years, mainly to improve growth, milk production or feed efficiency. Probiotics for adult cattle are supplied mainly to improve fiber digestibility and prevent rumen acidosis.

The purpose of the experiment is to evaluate the effect of a probiotic feed supplement on dairy cows' feed utilization and production.

The probiotic supplement we are going to study in this experiment contains spores from bacteria within the bacillus genus. In the experiment, we will study how the added bacteria affect the cows' feed consumption, milk production, feed digestibility and feed efficiency. We will also investigate whether probiotics affect the somatic cell count of milk.

Project starts in September, 2021.

Contact researcher

Bengt-Ove Rustas, bengt-ove.rustas@slu.se, tele +4618671663

Researcher at the Department of Animal Nutrition and Management; Feed science   

 

Cattle: Mastit treatment strategies

2021-04 – 2022-12

Inflammation of the udder, or mastitis, is the most common disease in Swedish dairy cows, and it is both painful for the affected animal and leads to loss of milk production and economic consequences for the dairy farmer. Modern techniques in automatic milking systems (milking robots) enable more detailed supervision of animal health and udder health status of dairy cows, compared to manual supervision and test milking once a month. However, we lack knowledge on how to utilize the modern techniques in the best way for the daily work in dairy herds. This pilot study is part of a larger research project on mastitis treatment strategies in Swedish dairy herds with automatic milking systems. The aims of the pilot study are to find out if information collected automatically in the milking robot can be used to evaluate the udder health of dairy cows, and how well that information corresponds to other information on udder health, collected by manual milk samples and test milking results.

Contact researcher

Lisa Ekman, lisa.ekman@slu.se

 

Cattle: Evaluation of vaccines against bovine respiratory syncytical virus (BRSV)

2023

The aim of this project is to evaluate vaccines against bovine respiratory syncytial virus (BRSV) in young calves with maternally-derived antibodies. These antibodies originate from the first milk of the mother and can protect the calf against disease by binding to pathogens. However, the same antibodies can additionally bind to vaccines and will thereby inhibit the effect of vaccination in young calves. Bovine RSV is very contagious and causes annual outbreaks of respiratory disease in Swedish cattle. A closely related virus, the human RSV, can likewise cause serious disease in humans, mainly in infants and elderly.

While vaccines against BRSV exist for cattle, no vaccine against HRSV is available for humans. This is due to adverse effects of earlier vaccines, a weak immune system in infants and the interference with maternally-derived antibodies. However, a break-through recently occurred in RS-vaccinology. A viral protein (the fusion protein) was stabilised in a form (Pre-F) that induces strong immune responses in humans and better responses than a commercial vaccine in calves with maternal antibodies. In contrast to when using commercial vaccines, the usage of Pre-F enables disease monitoring based on serology, which currently is carried out on a voluntary basis in Sweden. With a Pre-F-based vaccine, infected animals can be differentiated from those non-infected but vaccinated, which allows tracking the virus among herds, with the possibility to warn nearby counties. Within the project, the immune response to candidate vaccines based on different parts of PreF will be evaluated in calves and the calves that will stay in the herd will be followed up throughout their life by blood sampling. If a natural BRSV-infection occurs in the herd during the lifespan of the animals, the clinical and virological protection of the vaccines will be evaluated.

 

Contact researchers

Jean Francois Valarcher, jean-francois.valarcher@slu.se, tel., +4618671351.

Other participants in the project

Sara Hägglund, sara.hagglund@slu.se, tel., +4618671891.

 

Cattle: Biomarkers for detection of subacute ruminal acidosis (SARA) in dairy cows

2023

The Swedish dairy industry has made significant improvements in animal welfare, feeding, disease control and herd management. However, diagnosis and prevention of a very common metabolic disorder, subacute ruminal acidosis (SARA), remains a challenge. Even in well-managed dairy herds, 11 to 26% of SARA cases are suspected in cows in early to mid-lactation period, resulting in significant direct and indirect economic losses, and leading to suffering in domesticated cows. SARA lacks clear symptoms, and is difficult to diagnose with existing methods. We propose to fill this gap by identifying metabolites in bio-fluids associated with the onset and progression of SARA using state-of-theart metabolomics techniques and developing a novel paper-based test for early detection. Our goal is to provide a novel detection method for SARA, support cattle welfare, make the dairy production more sustainable and efficient and promote climate-friendly production through optimal feed conversion.

Contact researchers 


Horacio Gonda, horacio.gonda@slu.se, tel.: +4618672350

Rebecca Danielsson, Rebecca.danielsson@slu.se, tel.: +4618671628

Other participants in the project

Jean Francois Valarcher, jean-francois.valarcher@slu.se, tel., +4618671351.

Sara Hägglund, sara.hagglund@slu.se, tel., +4618671891.

Bengt-Ove Rustas, bengt-ove.rustas@slu.se, tel.: +46722446955

Torsten Eriksson, Torsten.Eriksson@slu.se, tel.: +4618671643

Maria Åkerlind, maria.akerlind@vxa.se

                             

Pig: Completed projects

Pig: Reproduction issues in organic pig production

Principal investigator: Professor Ulf Magnusson, institution of clinical research, department of reproduction. Research group; phD student Ola Thomsson; vet med dr Ann-Sofi Bergqvist; vet med dr Ylva Brandt; vet med dr Lena Eliasson-Selling, Swedish Animal Health Service.

In this study the effect of length of time spent by lactating sows in individual pens before group housed will be investigated. In order to see if the time spent will have an impact on litter weights, piglet mortality and the synchronisation of the sows to show heat around the same time after weaning.

The main purposes of the investigation are to examine the reasons for the two main issues of organic pig production.

1) High piglet mortality from birth to weaning, low litter weights with large variation within litters.

2) The batch-wise management system with intact sow groups is difficult to apply as ovulations, and subsequent breeding, of the sows is spread out in time since some sows come into oestrus during the late lactation period.

In our studies, the maternal-piglet bonding, lactational anoestrus and natural oestrus-induction will therefore be explored to resolve the abovementioned issues. The overall aim of the project is to provide biologically based principles for improved health and performance in Swedish organic piglet production

The project receives financial support from the research council Formas.

Contact

ulf.magnusson@slu.se

 

Pig: Faba beans for pigs in conventional and organic production - properties and possibilities of different cultivars

The goal with this project is to increase our knowledge about the feeding value of faba beans, and to find out if/how colour-flowered can be used in pig feed.

Our dependence on imported soy has recently become an issue. Faba beans may at least partly replace the soy. This is important for conventional as well as for organic production. The white-flowered cultivars are recommended for pig diets. The colour-flowered cultivars have better yields and disease-resistance, but the contents of antinutritional factors (ANF), particularly tannins, has limited their use in pig feed. The tannin level varies between cultivars within the colour-flowered group.

In this project we will study the contents of nutrients and ANF in cultivars grown in Sweden, choose 2 colour-flowered with high and low ANF content and compare these and a white-flowered in a feeding experiment with weaners. The experiment will be performed in 2 parts, one conventional, and one organic ie no amino acids added in the feed.

Contact

Emma Ivarsson, Maria Neil

Emma.Ivarsson@slu.se, Maria.Neil@slu.se

+46 (0)18-672044, +46 (0)737-033348 (Emma), +46 (0)18-674538, +46 (0)73 631 11 80 (Maria).

 

Pig: Inclusion of intensively processed silage in diets to growing/finishing pigs

Lay crops for pigs are usually given in the form of silage and it is of great importance to investigate their potential as a source of nutrition and to find suitable feeding methods for good nutrient utilization and ability to perform natural behaviors. Pigs fed with total mixed ration feed where silage has been chopped and mixed with the other feed ingredients sort however out parts of the silage, which has a negative impact on growth. It is still interesting because silage will occupy the pigs in contrast to pelleted feed. The major challenge of feeding pigs with silage is, in addition to maintaining high nutritional quality, also finding feeding techniques that reduce the amount of sorted out feed, without losing its function as enrichment. We intend to investigate how an even shorter length, than those about 1-3 cm for chopped silage, influence the feeding behavior of the pigs. Silage that have been chopped and then intensively manipulated in a bioextruder, will result in a finer structure. We believe that by this, the different feed ingredients can be tied together further and reduce the pigs' ability to sort out different parts of the feed. This will increase the consumption and nutrient utilization of the silage. The feed will probably also be able to serve as an enrichment for the pigs and occupy the pigs to a great extent.

Contact

Magdalena Åkerfeldt, magdalena.akerfeldt@slu.se, +46 (0) 18 671716

Other participants in the project

Sara Holmström, sahm0004@stud.slu.se

 

Pig: Inclusion of silage in pig feed

The aim of the project is to evaluate the usefulness of grass / clover silage as a locally grown feed resource in organic and conventional pig production. The specific intentions of the project are to study how inclusion of silage in pig feed affects pig activity and social interactions and to gain more knowledge about how the intestinal microbiota changes through the incorporation of fibers from ley crops in the pigs' diets, and the relationship between microbiota-gut brain and pigs’ behavior (e.g. ability to handle stress).

Contact researchers

Magdalena Åkerfeldt, magdalena.akerfeldt@slu.se, tel. +4618671716

Johanna Friman, PhD student, Johanna.friman@slu.se, tel.+4618672300

 

Pig: Ley crop silage with red clover in the feed for sows

The aim of the project is to evaluate the use of locally produced ley crop silage with red clover in the feed for sows. The purpose of this study is to investigate how phytoestrogens in red clover are metabolized in pigs, and it affects the fertility and reproduction of sows. The study is expected to provide more knowledge about how the metabolism of these substances occurs and how it affects reproductive properties and is important to be able to make safe recommendations on the possibilities of including red clover in silage for sows.

Contact Researchers

Emy Vu (PhD student), emy.vu@slu.se,  tel. +18672046. Department of Animal Nutrition and Management.

Magdalena Åkerfeldt (resercher),magdalena.akerfeldt@slu.se, tel. +46181716. Department of Animal Nutrition and Management.

Other participants in the project

Ann-Sofi Bergqvist, Ann-Sofi.Bergqvist@slu.se,  tel. +4618672986

Torbjörn Lundh, torbjorn.lundh@slu.se,  tel. +4618672137

Anneli Rydén, anneli.ryden@slu.se,  tel. +4618671890

 

Pig: Good leg quality in sows - better phenotypes for genetic and genomic selection

In addition to being painful for the affected animal, poor leg quality and lameness in sows is also linked to other welfare problems such as increased piglet mortality. The long-term goal of this project is to more efficiently identify sows with good leg strength and good movements, thereby improving the welfare of both sows and piglets.

We will focus on improved phenotypes and the development of a genetic test for leg health. A lame sow is likely to move less compared to a healthy sow. The activity level of sows will be measured automatically with so-called accelerometers. These record the frequency of position changes. This information will be validated against assessments of the sow's leg conformation. Pressure mat will be used to identify lame animals. Activity measured by data loggers and technicians' assessments conformation will be related to sow fertility and piglet survival.

We have probably identified a gene that controls inheritance of hind leg position in pigs. The project intends to verify these preliminary results via extended sampling and analysis. The purpose is to improve animal health by being able to identify animals that have a tendency for poor leg posture with a simple blood test.

Contact researchers

Katja Nilsson, Katja.Nilsson@slu.se, tel. +4618674534

Anna Bergh, Anna.Bergh@slu.se, tel. +4618672152

 

Pig: Colostrum in sows

The study aims to investigate some physiological parameters, namely blood pressure and the level of antibody in colostrum in sows, and its impact on piglet mortality, and to evaluate a non-invasive method to measure sows' blood pressure at birth compared to blood pressure in different stages of gestation.

Contact Researcher

Anna Carlertz, anna.carlertz@slu.se, +46739364230

 

Poultry: Completed projects

Poultry: On-farm hatching

The broiler chickens of Sweden are delivered by a few large hatcheries. For an egg to develop into a chick, it takes approximately 21 days. The biological variation however, results in a hatching window stretching from day 19 to 21. In traditional hatchers there is not possible to provide the chicks with feed and water during incubation, early hatched chicks are therefore feed deprived for quite sometime. Although the chicks are supplied with nutrients from their yolk sac, they might risk dehydration and a poorer developed immune system. Lately, an on-farm hatching concept has been introduced in the Netherlands. Fertilized eggs are transported to the grower facilities at embryonic day 18, enabling free access to feed and water immediately post-hatch regardless of when during the hatching window a chick hatches. The hypothesis is that chicks hatched on farm with immediate access to feed and water and that are not subjected to transportation and handling directly post-hatch have a better developed immune system, an earlier organ development and a slaughter weight equivalent to that of hatchery chicks. Because the concept of on-farm hatching has not yet been investigated in Sweden, this is a very much needed study.

Contact

Malin Boyner, Malin.Boyner@slu.se, +46 18-67 12 57

Poultry: The influence of lactic acid bacteria on Campylobacter in the bowel of the chicken

Project starts 19 January, 2018

Campylobacteriosis is the most commonly reported zoonosis in the EU and large parts of the world and poultry is the major source of human infection. According to EFSA 50-80% of human Campylobacter infections are attributed to poultry. With a strict monitoring programme, Sweden has managed to reduce the incidence of Campylobacter in slaughtered conventional broiler flocks. However, the prevalence is higher when chickens are provided access to outdoor areas due to increased contacts with wild animals such as birds, flies and rodents that are all known to carry Campylobacter.

The aim of this trial is to study possible changes in intestinal microbial profile in fast and slow growing chicken genotypes at a daily intake of Lactobacillus spp. supplied via silage or water and observe if this treatments can reduce the prevalence of C.jejuni in chickens.

Contact

Eliška Valečková (HUV, SLU), eliska.valeckova@slu.se, Phone: +42-073-450 31 12

Helena Wall (HUV, SLU), Helena.Wall@slu.se, Phone: +46 (0)18-67 16 70

Emma Ivarsson (HUV, SLU), Emma.Ivarsson@slu.se, Phone: (0)18-67 20 44

Other participants in the project

Patrik Ellström (Uppsala Universitet), patrik.ellstrom@medsci.uu.se, Phone: +46 (0)18-471 66 51

Poultry: Optimized nutrition and management for hatching for a more robust chicken – part 2

The content of the first feed a newly hatched chicken receives has a large impact on the development of the chicken. Except for raw ingredients that fulfil the nutritional needs of the chicken so called bioactive substances be included in the feed in order to stimulate a healthy gut flora and an improved immune defence.

Gothenburg University cultivates brown macro algae on rope along the Swedish west coast, the algae contain substances not found in terrestrial plants that are ascribed bioactive properties in the literature. In lab trials last autumn the fiber laminarin proved promising, therefore the trial feed will be supplemented with laminarin extracted from the brown algae Laminaria digitata. Birds are poor at breaking down fibers in their digestive tract. Some fibre break down does, however, occur in the chicken's ceca, forming bioactive molecules that in small amounts may stimulate a healthy gut flora and improve the immune defence.

The aim of this project is to evaluate the possibility to via the first feed of the chicken stimulate both its gut function as well as immune defence. The hypothesis is that feed with prebiotic components from algae will give a more robust chicken and that the positive effect is strengthened when feed and water are given already at hatch.

Contact

Jolin Währn, jolin.wahrn@slu.se, +46 (0)18 67 20 30

Helena Wall, helena.wall@slu.se, +46 (0)18 67 16 70

Emma Ivarsson, emma.ivarsson@slu.se, +46 (0)18 67 20 44

 

Optimal light environment for the laying hen

Vision is the laying hens´ most important sense that guides them in their daily activities such as finding food, recognizing fellow birds and move around safely in more complex housing systems. Birds´ visual system differs from the human and hens are more specialized to be day active and require certain light intensities and a broader spectrum containing UV to have an optimal vision. However, high light intensities in the housing, especially if it is distributed in a patchy way, can be related to problems with e.g. feather pecking. A common solution to reduce feather pecking, if it occurs, is to lower the hens´ overall activity level by reducing the light intensity, likely impairing birds´ ability to perform important behaviours. Thus, providing hens with a suitable light environment is a challenge. This project will investigate the visual ability of laying hens on a detailed level in different light spectrums and intensities using individual behaviour tests and physiological measures. Effects of the most promising light regimes on behaviours such as feather pecking will be assessed on group level with the aim to find a light regime that contribute to a good welfare under practical conditions.

Contact 

Anette Wichman, Anette.Wichman@slu.se, +46 18-672316

 

Preparing for the challenges and opportunities of life: effects of early experience on adaptive plasticity in laying hens

Farm animals are often reared in one type of environment but housed as adults in another. When moved, a lack of skill needed to adapt rapidly to the new environment can compromise welfare. “Adaptive developmental plasticity” is a phenomenon whereby early experience shapes later responses, leading to individuals with greater adaptive capacity and resilience to stress.

We hypothesize that exposure to a diverse and stimulating early environment will prepare chicks to better cope with challenges and exploit opportunities later in life as adult laying hens. We shall systematically varying the predictability and controllability of environmental enrichments of types that could be implemented in commercial practice during the brooding period (e.g. varying litter materials and perch designs). Their effects on behavioural, physiological, immunological and cognitive development will be compared at different ages. Besides identifying how best to prepare chicks to cope with future stressors (so minimizing reductions in welfare), this study will investigate how developmental plasticity can enhance positive aspects of welfare, such as exploration skills that help hens quickly find food and use nest boxes and other new resources when moved to the laying house.

Contact researchers

Linda Keeling, linda.keeling@slu.se, phone: +4618671622

Professor at the Department of Animal Environment and Health; Animal Welfare Unit

Lena Skånberg, lena.skanberg@slu.se, phone: +4618671343

Doctoral Student, Research Assistant at the Department of Animal Environment and Health; Animal Welfare Unit

 

Adapted management and feeding strategies for improved chick quality

The content of the first feed a newly hatched chicken receives has a large impact on the development of the chicken. Except for raw ingredients that fulfil the nutritional needs of the chicken so called bioactive substanses be included in the feed in order to stimulate a healthy gut flora and an improved immune defence. Lantmännen Agroetanol AB has developed a process by which the edible fungi Neurospora intermedia is grown on the residue from ethanol production. Like many other fungi the cell walls of N. intermedia are largely made out of chitin. Birds are poor at breaking down chitin in their digestive tract. Some break down of chitin does, however, occur in the chicken’s ceca, forming chito-oligosaccharides that in small amounts may stimulate a healthy gut flora and improve the immune defence. The aim of this project is to evaluate the possibility to via the first feed of the chicken stimulate both its gut function as well as immune defence. The hypothesis is that feed with prebiotic components from fungal protein will give a more robust chicken and that the positive effect is strengthened when feed and water are given already at hatch.

Contact researchers

Helena Wall, helena.wall@slu.se, phone: +4618671670

Emma Ivarsson, emma.ivarsson@slu.se, phone: +4618672044

Department of Animal Nutrition and Management

 

Mother knows best – improving rearing conditions for chicks by recreating maternal care

Under natural conditions, chicks are cared for by a broody hen who helps them direct pecking behaviour to food sources, establish behavioural synchrony (effectively separating active from inactive birds) and to regulate fear responses. All these maternal guided behaviours help reduce the risk of feather pecking, which is a major welfare concern. Indeed, chicks reared by a broody hen are less fearful and less likely to develop feather pecking than birds reared without maternal care. In spite of this, approx. 7 million chicks are incubated, hatched and reared in Sweden without maternal care. In a commercial situation, it is not feasible to keep adult and young birds together due to bio security and practical reasons. In this project, we will investigate if it is possible to recreate different aspects of maternal care during rearing and produce similar welfare improvements as those observed when rearing chicks with a broody hen. Hens communicate with her chicks by using specific types of calls (e.g. food, roosting and maternal cluck) and behavioural displays. For this reason, we will utilize a combination of audio and video playbacks of these calls and behaviours near key resources to attract the chicks and encourage them to utilize the resources. By doing so, we expect that chicks will be able to find key resources soon after hatching, help them direct pecking behaviour to food (rather than feathers), establish behavioural synchrony, reduce fearfulness and feather pecking.

Contact researchers

Carlos Hernandez, Carlos.Hernandez@slu.se, tel. +46 (0)18 67 16 37

Anette Wichman, Anette.Wichman@slu.se, tel. +46 (0)18 67 23 16

Linda Keeling, Linda.Keeling@slu.se, tel. +46 (0)18 67 16 22

Jenny Yngvesson, Jenny.Yngvesson@slu.se, tel. +46 (0)511 67 229

Harry Blokhuis, Harry.Blokhuis@slu.se, tel. +46 (0)18 67 16 27

 

Brown algae as a feed supplement for broilers

Except for raw ingredients that fulfil the nutritional needs of animals, so called bioactive substances be included in the feed in order to stimulate a healthy gut flora and an improved immune defence.

Brown algae contain substances not found in terrestrial plants, such as complex carbohydrates that are ascribed bioactive properties in the literature. In previous lab trials the fibre laminarin proved promising, therefore the trial feed will be supplemented with laminarin extracted from the brown algae Saccharina Latissima. Moreover, intact algae are good sources of minerals, carotenoids, vitamins, pigments and chelated micro-minerals which are claimed to have a high bioavailability and are therefore also interesting to evaluate. In the first part of this experiment the ability of algae to affect transfer of antibodies and nutrients from the hen to the egg and in the extension the effect on chick quality be studied in broiler breeders. In the second part of the study the focus is the first two weeks on chick quality and how it is affected firstly by what the chick get from the egg and secondly by laminarin. The last weeks of the experiment, the aim is to see if laminarin can affect the chickens resistance to a Campylobacter infection.

Contact researchers

Emma Ivarsson, emma.ivarsson@slu.se,  tel. +4618672044

Helena Wall, helena.wall@slu.se, tel. +4618671670

Malin Boyner, Malin.Boyner@slu.se, tel. +4618671257

Department of Animal Nutrition and Management (HUV).

 

Feeding live larvae to laying hens – Study 1

Background and aim:
We are testing diets for laying hens with different amounts of the daily nutrients being delivered in the form of live black soldier fly larvae.  We will compare the effect of these different amounts of live larvae in the diet on feed intake, bird growth, egg production, egg quality, and behaviour. We will determine which amount of live larvae in the diet is the most appropriate and if hens are capable of self-balancing their nutritious intake to remain healthy and maintain egg production. The study will have 40 individually housed hens and will assign them to 4 different treatments (10 hens/ treatment):

  1. 10 % of nutrients as live larvae (rest given as pellets)
  2. 20% of nutrients as live larvae (rest given as pellets)
  3. Self-balancing diet (feed components given separately and ad libitum larvae)
  4. Control (commercial pellet feed only).

Contact researchers

Fernanda Tahamtani, fernanda.tahamtani@slu.se, phone: +46767409787

Carlos Hernandez, carlos.hernandez@slu.se, phone: +4618671637

Department of Animal Nutrition and Management (HUV).

 

Feeding live larvae to laying hens – Study 2

Background and aim:
Following the results from study 1, we are progressing with the project. The aim of study 2 is to identify which of three larvae delivery methods most promotes foraging behaviour. The study will have 90 hens housed in groups of 5 in 18 pens. The pens will be assigned to one of three treatments (6 pens/treatment):

  1. Larvae provided in dedicated troughs
  2. Larvae scattered in the litter in the morning
  3. Larvae scattered in the litter throughout the day

We will monitor hen behaviour in the home pens with the use of cameras.

Contact 

Fernanda Tahamtani, fernanda.tahamtani@slu.se, phone: +46767409787

Carlos Hernandez, carlos.hernandez@slu.se, phone: +4618671637

Department of Animal Nutrition and Management (HUV).

 

Poultry: Lifelong and intergenerational mitochondrial, physiological and epigenomic effects of early metabolic challenges

Background and aim:

Metabolic processes are the very basis of life and ensure that living organisms get the energy they need. In almost all plants, fungi and animals - including humans - the energy is generated in the mitochondria of the cells. Incredibly, these cellular machines are descendants of bacteria that entered the cells of our ancestors billions of years ago. Over time, they have evolved into one of our cells' foremost tools for responding to their environment, transforming signals from the environment into appropriate metabolic responses. A good understanding of this responsiveness is of great importance, for example in understanding the mechanisms behind how organisms are affected by climate change and to identify how mitochondrial dysfunction is involved in neurological and metabolic diseases, as well as cancer.

By linking external stressors with the mitochondrial epigenome and the physiology of the whole organism, this project will offer completely new insights into the emerging field of research that is mitochondrial biology. The results of this project will be valuable in several research fields, such as medicine, ecology and evolutionary biology, as they describe an important mechanism for translating environmental factors into functional changes in the very core of the cell's machinery.

Contact 

Carlos Guerrero-Bosagna, Uppsala University,  Carlos.guerrero.bosagna@ebc.uu.se

tele +46700895837

Other participants in the project

John Lees, john.lees@liu.se

tele +46702954864

 

Poultry: Reduced ammonia volatilization in poultry production by adjusted feed composition

Project 2023-2024

Within Swedish egg production, high ammonia levels are considered as the major environmental challenge. The majority of Swedish hens are kept in cage-free systems with access to a littered area which increases the behavioural repertoire of the laying hen in a positive way. However, manure accumulating in the litter will increase the ammonia concentration in the indoor air, as nitrogen in the manure is converted to ammonia by bacteria and in chemical processes. Lower levels of crude protein in the feed and thereby nitrogen in the manure decrease the risk of ammonia formation, however, a certain level of nitrogen in the feed is needed as building blocks for protein. Increased level of fibre in the feed might potentially also reduce the ammonia volatilization by increasing the microbial activity so more nitrogen is excreted as microbial more stable protein. The present project aims to evaluate if adjusted levels of crude protein, amino acids and fibre in the feed can lower the ammonia volatilization from the litter in laying hen facilities while animal performance and welfare are maintained.
 

Contact researcher

Emma Ivarsson, Emma.Ivarsson@slu.se
Helena Wall, Helena.Wall@slu.se, tel.: +4618671716
 

Other participants in the project

Adnan Aslam (PhD student within the project)
Erika Ohlsson – master student within the project

Other projects: Completed projects

The role of temperature in structuring insect communities

With a changing climate (IPCC 2014), the lifecycle of a living resource might shift in time as a response to new abiotic conditions. This is especially apparent in terms of phenological events, as for example a pollinator needs to match the flowering of its host plant and an herbivore needs to match the bud burst of its host plant. It has been suggested that climate change has already altered the phenology in a lot of plants and insects. Among plants, it has resulted in a temporal shift towards earlier bud burst and/or flowering, and among herbivorous insects in earlier emergences. Furthermore, various experimental and observational studies have shown that the shift in relative synchrony may vary between interacting species. Hence, with a warming climate, some herbivores may become active before plants, other herbivores will become more synchronized with their host plant whereas in a third case, plants may become active before the herbivore (Liu et al. 2011). However, Thackeray et al. (2016) recently suggested that under likely climatic scenarios, insects in general are likely to advance their phenology more than a lot of other taxa.

In this project, we will examine the synchrony among three trophic levels in a model system: oaks, their herbivores and the parasitoids of these herbivores. By heating up these communities we intend to find out i) whether temporally synchronized organisms will slide out of phase and become temporally decoupled, and ii) if so, how this will affect the structure of the food web and the insect community.

Contact

Adam Ekholm (PhD student), adam.ekholm@slu.se, +46 (0)730 662 955


Contact Research and Education Coordinators

Lotta Jönsson, Research and Education Coordinator the Swedish Livestock Research Centre, SLU lotta.jonsson@slu.se, +4618673217

Johanna Grundin, Research and Education Coordinator the Swedish Livestock Research Centre, SLU johanna.grundin@slu.se, +4618671698

Linnea Eberson, Research and Education Coordinator the Swedish Livestock Research Centre, SLU linnea.eberson@slu.se, +4618672948