While Ohio’s heat wave with multiple 100 degree days has subsided, livestock producers still need to watch for heat stress symptoms in their herds as animals continue to deal with temperature swings and drought, say two Ohio State University Extension experts.
Forecasts for ongoing hot, humid weather combined with drought conditions in many parts of the state can be of concern for livestock, said Stephen Boyles, an OSU Extension Beef Specialist.
Hot weather and high humidity can reduce breeding efficiency, milk production, feed intake and weight gains, and can sometimes cause death, he said.
“High temperatures raise the concern of heat stress on cattle, which is hard on livestock especially in combination with high humidity,” Boyles said. “Livestock should be observed frequently and producers should take precautions when hot and humid weather is forecast including working cattle early in the morning to decrease the risk of heat stress.”
Already, the majority of Ohio is experiencing moderate drought, with areas in the western and northwest areas of the state near the Indiana border experiencing severe drought as of July 10, according to the most recent U.S. Drought Monitor.
While temperatures are expected to cool somewhat over the weekend in much of the state, forecasters expect them to rise into the 90s again next week. That is on top of the stress livestock faced last week, when temperatures reached triple digits with heat index values reaching upwards of 109 in many parts of Ohio.
For livestock producers, that means keeping abreast of weather forecasts and making contingency plans in the event of hot, humid conditions, Boyles said.
For example, the weather service issues special forecasts during extremely hot weather to alert livestock producers of dangerous weather. The warnings are based on a temperature-humidity index, which increases as the temperature and humidity increase. The danger level is indicated by an index value of 79, which is reached in various combinations of temperatures above 85 degrees in combination with high humidity.
“As temperatures increase, slightly lower humidity can still create dangerous and emergency conditions,” Boyles said. “The emergency level begins at an index level of 84 and occurs at temperatures in the 90- and 100-degree range, increasing in danger as the humidity level increases.
“When temperatures hit in the mid-to-high 90s, producers need to pay more attention to cattle behavior.”