Nutrition is another important factor in maintaining reproduction in the summer.
Research has demonstrated that negative energy balance is correlated with impaired reproductive performance. When cows reduce intake as a result of heat stress and fall into a negative energy balance situation, there are negative effects on plasma concentrations of insulin, IGF-1 and glucose, which result in poor follicular development, poor quality of oocytes and reduced expression of heat. Minimizing dry matter intake losses during heat stress is critical.
Keeping cows cool will result in more frequent meals and reduce slug feeding. It is a good idea to feed fresh feed more often, place extra waterers in return alleys and provide shade at the bunk area. Review your ration before the heat hits to make sure there is adequate fiber, potassium, sodium and buffers if needed.
Source: Faith Cullens, Michigan State University Extension