A morning stroll might just be what a vet will order now for a herd in heat stress. A Kansas State University faculty and student team have built a circular exercise device with moving panels that gently keep dairy cattle on a walking routine, and the results so far have been pretty cool.
“We are doing a project where we are looking at the effect of exercise on heat stress in dairy cattle,” said Tim Rozell, a professor of animal sciences and industry at K-State, in a recent release.” This is a real problem for dairy animals; they have a lot of struggles when it gets hot out, and we have hot summers in Kansas.”
The project includes a control group that doesn’t exercise; a low-intensity exercise group that walks at a slow pace for an extended period of time; and some heifers that receive high-intensity interval-type training with alternating periods of fast and slower walking at increasing rates, Rozell said.
Rozell said the university has conducted similar research trials for three years. Preliminary results from earlier tests conducted by Jessica Johnson, who was a doctoral student in animal science at the time and is now a teaching assistant professor of biology, show that cattle that exercise regularly spend less time in an elevated temperature, so they are less susceptible to the negative effects of hot days, according to Rozell.
“We see increased protein in milk from exercised cattle,” he said. “Last year, for example, we exercised pregnant heifers up to three weeks before they underwent parturition, and even 15 weeks or so into milk production, we saw increased protein in their milk, elevated lactose and other improvements in milk production.”
The exercise routines for the high-intensity group are similar to those followed by athletes.
“We’ve used a lot of human research in developing our exercise protocols,” Rozell said. “We’ve looked at something called lactate threshold in dairy cattle. We know about where they switch over their metabolic system from aerobic to anaerobic metabolism, and so we are trying to exercise them around that point, and that’s based on human research.”
Now that the team has shown exercise has positive effects on heat stress and milk production, Rozell said the university is moving toward developing recommendations that would help dairy producers incorporate sensible exercise protocols for their own herds.
