Grooming behaviour is expressed by many animals, including cows, and helps them maintain a healthy coat and skin. Cows can groom themselves and herd mates by licking. When housed in naturalistic environments, they also use trees or other structures to scratch parts of their body that are otherwise difficult to reach.
On some dairy farms, cows do not have access to surfaces suitable for scratching themselves, but other farms are now providing cows with automated mechanical brushes that facilitate grooming behaviour.
When cows are allowed access to mechanical brushes, they are cleaner and spend about fivefold more time grooming than when brushes are not available, suggesting that these brushes are important for the cow.
To better estimate just how important access to an automated mechanical brush is to indoor-housed dairy cows, researchers at the University of Britsh Columbia's Dairy Education & Research Centre conducted a study designed to test the motivation of dairy cows to access a mechanical brush.
Motivation testing can be used to assess how important resources are to animals. In motivation studies, the willingness of animals to work for access to a resource of interest (in this case a mechanical brush) is typically compared with the animal's willingness to work for other resources known to be important for the animal (e.g. fresh feed).
To see a video of a cow using the gate to access the brush visit:
This allows researchers to compare the relative importance of the different resources to the animal. Animals are generally highly motivated to feed, so feed can be used as a 'gold standard' to compare with other resources.
In the experiment, cows were trained to push open a weighted gate. During training, cows were rewarded with some grain after successfully pushing open the gate. It took about a week until all the cows learned to successfully open the gate from a closed position.
After the successful completion of training, the test sessions started. In the test sessions, the weight that cows were required to push to open the gate was gradually increased, thereby increasing the "work" required to access either a mechanical brush, fresh feed (tested after 1.5 hours of feed deprivation; a resource researchers assumed that cows would be highly mo(a resource researchers assumed that cows would not be highly motivated to access)tivated to access), or an empty pen .
To determine if testing order affected motivation to access the brush, all animals were tested twice: once before (Brush I) and once after (Brush II) they had been tested for motivation to access the feed and empty pen.
To access an empty pen, 4 of the 10 cows tested were not willing to push any weight, and the maximum weight pushed by any of the cows to access the empty pen was 14 kilograms.
In contrast, cows were willing to push higher weights to access either food or the mechanical brush, with many cows pushing 23kg and some pushing 41kg or more to access these resources.
The weight cows were willing to push was similar for the mechanical brush and for the fresh feed, and the weight cows were willing to push to access the mechanical brush did not differ between the first and second test phase.
The results of this study show that cows are highly motivated to access a mechanical brush, about as motivated as they are to access fresh feed after 1.5 hours of feed deprivation, and more motivated than they are to access an empty pen.
These results indicate that access to a mechanical brush is important for dairy cows, and provides scientific evidence in support of the practice of providing cows access to these brushes.D
For further information email email@example.com or firstname.lastname@example.org or website www.landfood.ubc.ca/dairy_centre.
This report is based on McConnachie et al., 2018. Biol. Lett. 14: 20180303.
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