This blog post was written by Jasmine Muszik and Shanaz Mokhtranazif
Cowlife McGill is wrapping up its latest trial on the impacts of outdoor access on movement-restricted dairy cattle. Producers and consumers alike are becoming increasingly concerned about the welfare implications for livestock who are denied the ability to exercise or go outside. Our labs’ past studies have demonstrated the importance of allowing cattle access to the outdoors, but our current goal is to establish how frequency of outdoor access impacts leg and hoof health and affective state. Starting November of this past year, our team used 47 dairy cows from the Dairy Unit on campus to study this topic. Three treatment groups were established; a control group that was not taken outside, a 3-exits group and a 1-exit group that were allowed outside for 3 days/week and 1 day/week, respectively. Before outings began, the animals were individually tested in three behavioural tests (a Human Approach Test (HAT), a Novel Object Test (NOT), and a Suddenness test (SUD)) to establish a behavioural baseline of the animal’s reactivity.
Starting two weeks before outing, there were also kinetic and kinematic data collections, where markers were attached to the cows and they were recorded while walking in a straight line using 8 cameras (i.e., 3 cameras for recording for each side (left and right), 1 to record them from the back, and one to record the front view) for kinematic gait analyzing. Also, statistic and dynamic data of the cows were recorded by Pressure platform while the animal was standing on them.
Blood samples were taken from all cows for hemogram and future serum analysis, as well as hair samples from the tails to measure cortisol level as an indicator of stress levels in the cows. In the last day of pre-trial data collection, hoof trimming was performed to assess claw lesions and measure claw dimensions and toe angle.
Following these tests, 5 weeks of outings began. The treatment cows that were going out were recorded for 20 minutes before being brought outside to capture anticipation to exit. They were also recorded for 30 minutes upon return to their stall to determine satisfaction of outing. Lastly, the treatment groups that remained inside during outings, were recorded for 15 minutes to establish frustration behaviour.
During these five weeks, thermography pictures were taken. Every Monday, the thermogram photos of the claws’ dorsal view were taken to assess weekly progress of the thermal distribution of coronary bands. In addition, thermal pictures of the cows’ muscle were taken (i.e. Semitendinosus, Semimembranosus,Middle gluteal, Gluteobicep and medial side of left and right hocks) before outing and 24h after outing, once per week for each treatment group.
During outings, the animals were recorded leaving and returning to the barn to establish motivation to access pasture (see Image 4). On their respective outing day, the exit treatments were led in groups of 3 to an outdoor pasture area divided into 6 paddocks. The groups were rotated to a new paddock weekly, and the cows were allotted an hour of outdoor access time whilst in the paddocks. During their outdoor time, 30 minutes of live behavioural observations were also taken using scan sampling, with a scan being completed every 3 minutes, to determine what behaviour the animal’s exhibited while outside.
Right after the end of 5-week outing and 8 weeks later, data collections were repeated for kinetic, kinematic, blood sampling and hoof trimming. As well, the Human Approach Test, Novel Object Test, and Suddenness test were repeated to evaluate the evolution of the cow’s reactivity over time.
Our hope is that the results of our trial will corroborate the expectation that greater frequency of outdoor access improves hoof and leg health, along with improving the animal’s reactivity to humans, novelty, and sudden events. This research will hopefully be an important step in increasing the awareness of farmers and the public on the benefits of giving movement-restricted animals the opportunity to go outdoors. Our passion is to continue to research issues related to animal welfare to improve the lives’ of dairy cattle and other livestock, and we look forward to sharing our journey as it progresses!
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