Batch number 4

A fourth batch was initiated February 2021, this time including 14 cow-calf pairs. One of the primary aims of this batch was to test two different lengths of cow-calf contact: separation at 4 months and at 8 months of age. This was partially done so as to see if any indications of natural weaning – either by cows or calves – could be observed prior to weaning at a late stage. As with the second batch, the cows and calves were housed indoors until pasture turn-out later in the spring. At one end of the pasture, the calves had exclusive access to a fenced-off area containing a sheltered deep-bedded area, as well as silage and water. Cow-calf pairs could interact in the remaining pasture area, while cows were free to move between the indoor pen and pasture as they pleased.

Photo: Teresa Johansson

Photo: Teresa Johansson

Weaning at 4 months

The calves were randomly assigned to either of the 2 treatment groups, and 7 of the calves were equipped with nose flaps in early July 2021, when they were approximately 4 months old. The nose flaps were worn for 3 days before they were removed and the calves were moved into an adjacent pasture. This new pasture shared the same shelter as before, although the deep-bedded lying area for the newly-separated calves was separated from the other calves with a solid wall. Cows whose calves belonged to the 4-month separation treatment were no longer allowed access to the pasture shared with calves, and instead were redirected to a further, adjacent pasture. At the end of this pasture area, the cows could access restricted contact with the calves over a section of wooden fencing. Live observations were conducted outside to explore various social behaviours – both between calves and cow-calf pairs – and play behaviours in the two treatment groups.

Photo: Teresa Johansson

Weaning the remaining calves

The second group of calves was originally planned to remain with their dams until they were approximately 8 months old. This length of time was decreased to 6 months when at least 1 cow began directing reproductive behaviours towards a calf. Mounting and standing to be mounted are natural behaviours performed by cows when they are in heat, but can present a dangerous situation for calves due to the size discrepancy. Due to concerns that the nose flaps used previously were causing the development of sores in the nasal cavity, the calves in this group were weaned and separated abruptly.