Some highlights from the Dairy Welfare Symposium
The first North-American Dairy Welfare Symposium was held in Guelph, Ontario, Canada, in late October. It was attended by about 300 people from 18 countries. The majority of attendees were from Canada and the U.S. but some came from as far as Australia, New Zealand and Japan. The first keynote speaker was David Fraser (University of British Columbia) who gave us a 30,000-foot view of animal welfare. He noted approximately 40 years ago when he started work in the field, interest was certainly not as high as it is today. Consumers now care about how animals are raised and that has led to more research and publicity about animal welfare and well-being. He said, “There are three different clusters of concerns – three somewhat different conceptions of animal welfare – one focused on the affective states of animals, one on natural living, and one on basic health and functioning. The three often go hand in hand.” An interesting point he made had to do with describing the science of animal welfare. When animal science replaced animal husbandry about a century ago, the housing, management and handling of animals that were included in the study of animal husbandry eventually became the science of animal welfare.
There was discussion about pasturing cows. Do cows really prefer pasture? A study at the University of British Columbia in the summer showed that when cows had free access to a freestall barn (with sand stalls) and pasture (they could choose the one they wanted). Generally cows preferred to stay in the barn during the day and in the pasture at night (as long as it wasn’t raining). Cows in the barn/pasture treatment had similar TMR dry matter intake and milk production to cows continuously housed in the barn. It seems that the grass they might have eaten while outside was used by their bodies to fulfill the additional nutrient requirements for walking. More research is needed to better understand cows’ preferences.
Another study at the University of British Columbia showed that cows seek isolation at calving. Researchers measured less stress when they provided a simple wall enclosure for cows to ‘hide’. They used a low cost plywood wall that could be easily installed in maternity pens. A larger animal sample size would be needed to show whether this housing strategy can lead to less metabolic problems and higher milk production. In another study, the same research group showed that sick dairy cows behaved differently than healthy cows after calving; they ate less and preferred to be more isolated from the group. They suggested that providing cows the opportunity to isolate from the group in early lactation may help in early disease detection.
Margit Jensen (Aarhus University, Denmark) summarized some of the welfare studies related to feeding and housing of dairy calves. Group housing of dairy calves allows them to perform natural social behaviors and acquire social skills. Studies in Europe have shown that calves housed in pairs or small groups were less fearful of an unfamiliar calf than calves housed individually. They had a lower heart rate during the confrontation than individually housed calves. In addition, pair-housed calves struggled less during restraint and blood sampling than individually-housed calves. Studies have also shown that interaction through bars for calves in individual pens did not appear to affect the development of their social skills as these calves behaved similarly to calves housed individually in isolation. Social stimulation from group or pair housing appeared to also influence feed intake and performance. In several studies, group-housed calves had a higher intake of solid feed than individually housed calves.
Milk feeding of calves in groups is beneficial for social development but it can have its challenges. Jensen said, “If calves are fed via computer-controlled milk-feeders, their individual milk intake is ensured, but calves typically occupy the feeder for much longer than it takes to ingest the milk and these feeders function best if milk allowance is high (she suggested 20% of body weight during the first 3 to 4 weeks, followed by 10% of body weight until gradual weaning), if minimal restriction is placed on the milk meal patterning, and if group size is small.”
Small group sizes can be economically challenging in the US. Our current study of dairies with automated calf feeders in the upper Midwest hopefully will help us identify best management practices for U.S. conditions with larger group sizes. We know some producers are making it work well. Therefore, we can learn the best approaches. By the way, the University of Minnesota will host the Precision Dairy 2013 Conference and Expo next June 26-27, where you can hear about automated calf feeders from Jensen and preliminary results from Endres (European and American experiences, respectively) along with many other topics related to precision dairy technologies. For more details, check the Precision Dairy 2013 website at precisiondairy.umn.edu.