Source: Dairy Research Cluster
For more than 20 years, David Fraser, Dan Weary and Nina Von Keyserlingk at the University of British Columbia have been the Natural Sciences and Engineering Research Council (NSERC) – Industrial Research Co-Chairholders in Dairy Cattle Welfare. This team has been leading the science of animal care and welfare practices in the Canadian dairy sector and internationally. DFC and a number of other sector partners have financed the Chair since it was created in 1997 and in 2019, the Chair was renewed for another five years with DFC support and several other partners.
The scientific results have helped farmers continuously improve their practices, establish standards for the evaluation of the animal care module of proAction® and served as evidence for revisions to the Code of Practice for the Care and Handling of Dairy Cattle (2009).
Highlights of results from the 2014-2019 research program:
Calves fed high volumes of milk and raised in pairs or in groups experienced benefits for their health, welfare and behaviour (social adaptation).
Building on work started early on in the Chair’s history where research showed tremendous weight gain benefits to feeding calves more milk (up to 12 Litres per day) via a nipple (on average daily gain was about 0.90 kg/d) accompanied by reductions in cross sucking, the group moved to explore social housing. Studies of calves paired or housed in groups, showed that calves ate more starter and gained more weight compared to calves housed individually.1,2 Pair housing also improved starter intake (at 3-10 weeks old), improving daily weight gain by an average of a 130 grams per day more compared to individually housed calves.
From a behavioural perspective, the benefits observed of housing calves with a partner included better socialization and learning and reduced distress response at weaning. For instance, calves in paired housing adapted sooner to new feed, were calmer when moved to new environments and did better when subjected to cognitive tasks.3
Heifers benefited from having a social role model for adaptation to situations like a new housing environment.
Studies found that heifers reared in open pens showed reduced lying and feeding times when first introduced to free stall housing. But when a role model like an experienced cow was with heifers, the heifers adapted to stall use more quickly.4 The team concluded that grouping heifers with experienced older animals positively affected their behaviour and adaptation to pasture and new housing systems.5
The transition period is a critical time for cows and a number of studies were completed to help improve transition cows’ health and care.
- A study concluded that an unpredictable and competitive social environment before calving causes changes in feeding and social behaviour, leading to changes in health status and increases the risk of uterine disease in multiparous cows after calving.6
- Reducing lameness during the dry period and avoiding over-conditioning at dry-off likely promotes improved transition health.7 The researchers found that lameness at dry-off was associated with metritis and transitional diseases, but not with subclinical ketosis. An association between lameness and transitional diseases is partially mediated through reduced feeding time.
- A high incidence of lameness during dairy cows’ dry period was observed; hoof trimming before the dry period reduced the risk of lameness for primiparous cows but not for multiparous cows.8
- Low body condition at dry-off and non-infectious hoof lesions in the weeks before dry-off were associated with chronic lameness during the dry period.9
- Changes in feeding, social and lying behaviors can help identify cows at risk of metritis. Cows ate less, were replaced at the feed bunk more often and spent less time lying down compared to healthy cows10 during a two-week period before calving and at 3 days before a clinical diagnosis of metritis.
Cows’ motivation to access the outdoors varies with time of day and season and providing a mechanical brush in the barn can be an important resource for the animals.
The researchers studied free stall housed cows’ motivation to access pasture. They gauged the cows’ motivation by having them push on a weighted gate to access fresh feed compared to a weighted gate used to access pasture. Weights on the gates were gradually increased over time by the same amount to test the animals’ motivation. They found that cows will work as hard to access pasture as they will to access fresh feed. Cows also worked hardest for outdoor access in the evening.11 When given the choice, cows housed in free stalls spent 25% of their time on an outdoor pack in summer and primarily at night. In winter, they spent 2% of their time outside. On an outdoor pack, cows spent 53.7% of the time lying down during the summer and 4.7% of the time lying down during the winter.12
Similarly, the researchers tested cows’ motivation to access a mechanical brush using a weighted gate system. Cows were trained to push a weighted gate to access fresh feed, a mechanical brush or the same space without a brush. They observed that cows are highly motivated to access a mechanical brush for grooming, suggesting that this is an important resource for these animals.13
Improvements for animal care at calving
Their studies found that cows that were calving preferred sand or concrete flooring, suggesting that these types of flooring may provide better traction for bouts of lying and standing when calving.14 They also demonstrated that cows that were calving preferred visual isolation from others and if provided the option, they will hide behind a barrier. The researchers recommend that providing a plywood barrier for cows when they are calving is a simple and low-cost method of meeting a cow’s need for isolation when calving.15
Benchmarking practices for improved dairy cattle welfare on commercial farms
The researchers tested farmers’ use of benchmarking reports to measure dairy cattle growth rates and transfer of immunity from colostrum in dairy calves. The use of reports resulted in a majority of farms making at least one management change in consultation with their veterinarian to improve their results.16 They concluded that benchmarking specific outcomes associated with calf rearing can motivate producer engagement in calf care, leading to improved outcomes for calves on farms that apply relevant management changes.
What’s next? In 2019, a new five-year NSERC-IRC program (2019-2024) was launched by co-Chairs Dan Weary and Marina (Nina) von Keyserlingk. Over the next 5 years these two scientists will combine practical studies on commercial farms with a series of experimental studies conducted at the UBC Dairy Education and Research Centre. The objectives for the new program following industry partner consultations are focused on: calf and heifer rearing, cow health and lameness, housing facilities and management, and painful procedures.
IRC Chair in Dairy Cattle Welfare overview
Chairholders: David Fraser, Marina (Nina) von Keyserlingk, Dan Weary (University of British Columbia)
Current Investment Partners: Natural Sciences and Engineering Research Council (NSERC), Dairy Farmers of Canada, Alberta Milk, BC Dairy Association, Boehringer Ingelheim (Canada) Ltd., BC Cattle Industry Development Council, Dairy Farmers of Manitoba, Intervet Canada Corp., Lactanet, Saputo Inc., SaskMilk, and Semex Alliance.