How to care for dairy cows well in hot weather
The suitable temperature for dairy cows is 10°C to 20°C. In summer, high temperatures and humidity can easily cause reduced appetite, low spirits, and decreased milk production in dairy cows. Good feeding management at this time can reduce the degree of heat stress in dairy cows and allow them to maintain stable and high production in summer. Recently, a reporter interviewed Professor Lin Qing, a member of the expert advisory group of this newspaper and of the College of Animal Science and Technology at Northwest A&F University, asking him to guide farmers on how to raise dairy cows well in hot weather.
Maintain ventilation? In the hot summer, farmers should strengthen air convection inside the barn. Reserve ventilation holes in the roof of the cow barn, install large exhaust fans and electric fans with relatively large air volume inside the barn, and increase the speed of airflow in the barn to carry away heat from the cows' body surface. Lin Qing said that when the temperature is above 29°C and the humidity is above 50%, cooling is needed from 5 a.m. to 1 a.m. At night, the difference between the cows' body temperature and the air temperature is relatively large, so the air supply time can be shortened.
Shower cooling? Install spray equipment on the roof of the cow barn to lower the temperature inside the barn. Showering the cows' bodies can directly cool them and enhance evaporative heat loss. When the temperature inside the barn exceeds 26°C, spray for 3 to 5 minutes at intervals of 30 to 45 minutes; when the temperature inside the barn reaches 26°C, spray water for 1 minute at intervals of 30 to 45 minutes. Lin Qing reminded that after spray cooling or shower cooling, be sure to turn on fans or blowers to exhaust air, so as to reduce humidity inside the barn.
Adequate drinking water? Dairy cows drink a relatively large amount of water, and in the hot summer, their water intake will increase further. In hot weather, provide dairy cows with fresh, clean drinking water, preferably cool water, deep well water, or freshly drawn tap water, ensuring this once every two hours. The water quality must meet drinking water hygiene standards, and after each drinking session, the water trough should be washed clean. Lin Qing suggested that Huoxiang Zhengqi Shui can be added to the cows' drinking water, as it has a good heatstroke-prevention effect.
Scientific feeding? Increase the nutrient content of the daily ration and reduce the amount of roughage fed. Increase the proportion of concentrate (but not more than 60%), increase the protein level of the daily ration, and the protein content can be increased to 18% to 20% of the daily ration. Feed more green, high-quality forage, such as carrots, bean dregs, beer dregs, and other succulent feeds. Lin Qing said that during periods of high temperature and drought, when green grass is scarce, dry grass can be used instead of green grass for feeding.
Increase nutrition? In hot weather, increased breathing and sweating in dairy cows often cause mineral deficiencies. Therefore, the content of minerals such as potassium, sodium, and magnesium should be increased in the daily ration. Potassium can be increased to 1.2% to 1.5% of the dry matter of the daily ration, sodium to 0.5%, and magnesium to 0.3%. Each dairy cow can be supplemented daily with 60 to 80 grams of potassium chloride, 100 to 150 grams of sodium bicarbonate, and 30 to 50 grams of magnesium chloride. After a dairy cow suffers heatstroke, the amount of vitamins fed needs to be increased. Vitamin C at 0.04% to 0.06% and vitamin E at 3 to 5 times the normal amount can be added to the dairy cow feed.