Not all dairy groups experience heat stress the same. Some groups require more careful attention to manage heat stress. In this podcast series, UW-Extension and industry specialists talk about the nutritional and water needs for the summer, especially during periods of heat stress. Randy Shaver, PhD, Dairy Nutrition Specialist and Professor for UW-Madison/UW-Extension, Matt Lippert, UW-Extension Wood County Agriculture Agent, and Liz Binversie, UW-Extension Brown County Agriculture Educator, talk about the groups that typically need a little more specialized attention.
Randy Shaver, PhD, Dairy Nutrition Specialist, UW-Madison/UW-Extension
Matt Lippert, Wood County Agriculture Agent, UW-Extension
Liz Binversie, UW-Extension Brown County Agriculture Educator
Time: 5:15 minutes
Liz Binversie: Greetings. I’m Liz Binversie, Agriculture Educator for UW-Extension in Brown County, Wisconsin. Today we will begin a new podcast series about heat stress and nutrition on the dairy farm. On the panel today is Randy Shaver, Dairy Nutrition Specialist and Professor for UW-Madison and UW-Extension; Matt Lippert, Agriculture Agent for UW-Extension in Wood County; and myself.
In the previous heat stress series, Mark Mayer told us that heat stress is the biggest profit robber on a dairy farm, but not all dairy cattle are impacted by heat stress in the same way. Randy, what are some high risk groups on the dairy farm that we need to pay special attention to when it comes to managing heat stress and why?
Randy Shaver: Well, Liz, I would certainly list first the baby calves—right from birth up through the first couple months of life—transition cows and these would be cows in the late dry period to 2-3 weeks prior to calving, and then the fresh cows in the first month of lactation, and then finally the highest producing cows, so if there’s a high group or a high string certainly those cows would be the most impacted by heat stress. In terms of the reasons why, these are animals that all have a great degree of stress. They have high growth requirements in terms of the baby calf. You have the stress of calving on the transition cow and then you have the lactational demands of the fresh cow and the high producing cow, and this puts a lot of stress on the immune system, and so it makes certainly the grouping, the cow’s environment, and also the nutrition critically important. In terms of the high producing cows, the biggest factor that we’re dealing with is dry matter intake, so in periods of heat stress it’s more difficult to get cows to consume adequate amounts of dry matter which contains the energy and protein and other nutrients that those cows need. It really creates a challenge and a need for more focused feeding and management during heat stress for those 3 groups of livestock. Matt, could you add some more on this topic?
Matt Lippert: Well thank you Randy. I think you nailed the groups that are most critical. If I could think of any others to add, certainly we do have hospital or sick pens on farms and if we have cows that have a fever or currently suffering with especially pneumonia and have been challenged with that maybe as a calf, any animals that have respiratory challenges or are compromised like mastitis cows, metritis cows. They’re not going to deal well with heat either. Another group I can think of is if we have animals that just with housing situations can’t get the protection from radiant heat, don’t have shade, possibly animals that are outside or pastured. These animals, even though often those animals are not highest performing groups, certainly can be stressed if our housing doesn’t provide the ventilation and air movement and shading that the other groups have. Liz, did you have anything to add to groups that are affected by heat?
Liz Binversie: Yes, Matt, thanks. Just wanted to mention something about our dry cows because they’re redeveloping their udder. They’re not producing, and they’re transitioning into a producing, lactating cow. Heat stress can negatively affect that udder development, and when that happens what we see is a decreased milk yield in the next lactation because that udder hasn’t been built back to its real full potential.
And thank you again to our wonderful panel today. If you have questions or would like to reach any of our panelists, you can reach them by email. Tune in next time to hear how you can adjust the diet to help reduce heat stress losses on the dairy farm.