Help dairy cows to beat the summer heat
by rfergusonlaw.com ·
How do you know if summer heat is negatively affecting dairy cows?
According to Angie Olnes, a dairy educator at the University of Wisconsin in Manitowoc County, if you start feeling hot when you’re outside, it’s probably too hot for the cows. If the temperature is 68 or higher on the temperature and humidity index, cows begin to feel heat stress, which often occurs before humans begin to feel it.
“A temperature and humidity index of 68 equates to a 70°F day with 65% humidity,” Olnes points out. “They may not be sexy, but they are.”
Regardless of the animal’s life stage, providing hypothermia for all ages has been shown to be beneficial.
The first line of defense is to limit cows’ exposure to direct sunlight in the shade, Olnes says. “They also need aeration, and they need a lot of water.”
A dairy cow’s respiratory rate increases when it is exposed to heat stress.
“When cows lie down, they produce more heat,” Olnes explains. “When their breathing rate increases in an attempt to expel heat, this process reduces the amount of bicarbonate in the blood, which reduces the amount of buffers available in the rumen. Drooling helps cool their bodies.”
When cows are hot, they usually don’t eat enough, she says.
“When they eat, they feed on or excrete slugs, and that can lead to acidosis,” Olnes says. “The cow’s internal temperature peaks two hours after being exposed to high heat, and it takes four to six hours for it to cool down and return to normal.”
According to Extension Best Management Practices to help reduce heat stress in dairy cows, farmers should monitor feed intake and adjust fiber levels to ensure adequate fiber is present to enhance energy and milk production. Another thing to consider is adjusting the mineral content in the diet. With increased sweating and urination, more sodium and potassium are needed. If potassium is increased, it is recommended to increase magnesium as well.
“Cows drink more water when it’s hot,” Olnes says. “Add another water tank to the pen when it’s hot or while returning from the parlor. Cows will choose water over shade. For cows that live on pasture, it’s important to provide an additional water source,” she says.
“The main thing is to make sure you check hoses, pumps and water appliances to make sure water is available at all times,” she says. “In the summer, cows’ water consumption increases dramatically. They stand more in the summer to stay cool, and often stand around water, which blocks some cows’ access to that water. Make sure the water is refilled at the optimum rate. Sometimes the filter screens need to be cleaned Or you may need to add another pressure tank.
Use common sense when transporting livestock on a hot summer day. Consider putting fewer cattle in the trailer, and avoid transporting cattle between 11 a.m. and 4 p.m., the hottest time of day, Olnes explains. Avoid stopping. If you have to stop, make sure to make the stop as short as possible.
She suggests avoiding giving vaccines during hot weather, or giving them early in the morning or late in the evening when the weather is cooler. This allows livestock to control their immune response to the vaccine before the temperature starts to rise.
Producers should have sinks or sprinklers in the feed bed, holding barn and parlor, Ulness says.
“They should deliver a gallon of spray in three minutes or less,” she says. “In a feed bed, each nozzle should hit two or three cows at a time. This spray should be activated every 15 minutes, and as it gets hotter, it should be activated every 10 minutes or less.”
When the weather is hot, limit the number of cows in the holding barn. Consider bringing only a third to half of the pen instead of the entire pen. This is a very specific farm.
“Maintain your fan belts, making sure they are clean and ready to use before they get too hot,” says Olnes. “Fans work best if it’s not dusty. On a hot day, airflow and ventilation are important.”