Water is the most important nutrient for dairy cattle. During hot and humid temperatures, water requirements increase significantly. In this fourth and final podcast episode, UW-Extension specialists provide water recommendations to help keep cattle hydrated and to minimize the effects of heat stress this summer.
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: 8:46 minutes
Liz Binversie: Greetings. I’m Liz Binversie, Agriculture Educator for UW-Extension in Brown County, Wisconsin. Today we will conclude our series on nutrition and heat stress by talking about water requirements during these hot summer days. 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.
Water is the most important nutrient for dairy cattle and is required in even greater amounts during hot and humid temperatures. Matt, what are the water requirements for dairy cattle to help make sure they stay healthy and hydrated?
Matt Lippert: Well, thank you Liz. I think one of the interesting things about water is as you mentioned it’s consumed in the largest amount by dairy cows. In fact, roughly they are going to consume about 3 pounds of water per pound of milk. There’s variation on time of year. This is going to up drastically in these heat events—nearly twice potentially. Certainly size of cow and other factors will affect this. Cows need an abundant amount of water, and they need it readily available to them. As you mentioned, in heat stress this need sometimes taxes the systems that are adequate otherwise. Another thing I’d say is that we focus on the dry feed so much. We know the pounds of intake that the cows are eating, we monitor its changes, but water comes through a pipe and generally it’s not getting metered. It could be but typically we don’t have the numbers to know that. A lot of producers won’t even know typically what their number is, but probably a normal baseline is 3 pounds of water per cow per pound of milk. That converts to about 30 gallons per cow per day. But it can be 50 or 60 gallons per cow when we get the heat. Sometimes we see that just the systems that deliver that water become inadequate under heat stress. We need to make sure that we see those cows when they crowd. They tend to crowd around waterers, so again those social interactions and the crowding effects become exacerbated during heat events. In general, we want to have 2 feet of linear trough space for every 10 cows. For cows that are housed in group pens, we need to have at least 2 waterers, and as the pens become larger where we have crossovers, we should probably have a waterer in every one of those areas. We should make sure there is adequate space around those waterers—not just the waterer space itself—but space around those waterers so cows can move around. This is going to minimize the effects of dominant cows and more timid cows. Another interesting fact about water is that cows tend to drink on their way to, but especially when they leave, the parlor. We want to make sure we can get all the water that these cows possibly can consume. A really good thing besides the waterers in the pen is to make sure to locate some waterers in the connection areas, the drovers alleys that these cows are taking to get to and from the parlor. We’ll see that they’ll take good advantage of that. We also need to make sure that there’s either reservoir in the system or pump capacity so that when large groups of cows hit the waterer at the same time the system is adequate to maintain it. Typically, we talk about a 3-inch minimum level in the troughs so that when a cow goes to drink her water, she’s not lapping at the waterer. With all of that activity of cows at the waterer during heat, we’re probably going to have to step up our sanitation and cleaning of the waterer areas. With that heat, cows do deposit feed in water troughs and we start to see algae. We certainly know we’ve got all sorts of things growing in that waterer. We want to keep that waterer fresh and clean, so we’re probably going to need to do more exchanging, scrubbing, and cleaning of water areas. Just to summarize before I pass on, water is really important and sometimes overlooked because certainly there are things that we can do to help cows deal with the stress. Randy, did you have items to add to that list?
Randy Shaver: Well, Matt you did a great job covering everything really on my check list. I would just maybe reiterate a few points. Cows require a lot of water because they secrete a lot of water in their milk, so high producing cows certainly require a lot of water to be able to produce milk and eat a lot of feed. That’s important really all the time so everything that Matt mentioned is really important year round, but under these periods of heat stress they just become even more critical. Locations of waterers relative to coming back from the parlor and before they go to feed becomes very crucial during periods of heat stress. The linear feet of water space, the access, the availability are very critical as well as cleanliness that Matt mentioned so well. I would also like to mention that we tend to focus quite a bit on the high producing cow, but this issue of hydration becomes very, very important for those animals that are really under the most stressful periods. Again, going back to those young calves, it’s very important to have adequate water and fluids to stay hydrated and to avoid some of the health problems that they might encounter. Transition cows—particularly as they get closer to the time of calving and then transitioning into the lactation period—it’s very important to be able to adequately hydrate them. Also, the sick pens. We do have animals that may have mastitis. Others that might have a fever or for whatever reason they may be managed in a different pen. Having adequate waterers and adequate water supply and then certainly a clean water supply is very critical for those groups of animals as well. Liz, do you have anything you might want to add as well?
Liz Binversie: Thanks Randy. The only thing I’d add is that cows prefer a water temperature between about 63 to 82 degrees. The temperature of the water is also really important. They don’t like to drink water that’s too hot or too cold. Somewhere at about 70 degrees is pretty good. The other thing is if you aren’t monitoring your water usage and you do suspect maybe some water consumption problems or something along those lines, you can pick up some water meters that usually aren’t too expensive that you can set up and monitor the water consumption on your farm and see where you may be having some issues.
So with that, I’d like to thank again our panel for today. If you have questions or would like to reach any of our panelists, you can reach them by email. Next month we will be talking about reproduction and heat stress and how you can reduce reproductive losses during the summer.