Avoiding Heat Stress in Youth Livestock Projects Dr. Karl Harborth Even though summer does not officially arrive for a couple more weeks, summer temperatures have definitely arrived in the southern United States. Most of us are not comfortable when the temperatures soar into the upper 90s and higher, but the livestock projects that we have chosen to care for are much less comfortable than we are and are very susceptible to heat stress during this time period. It would not be an uncommon sight to drive by a pasture on a summer morning and a see a herd of cattle fighting for a spot in the shade or at the watering hole. This can make the dog days of summer very stressful for livestock, even when they are roaming in their natural habitat. Cattle, swine, sheep and goats all have thermoneutral zones (Comfort Zones) well below that of humans. A thermoneutral zone (TMZ) is the range in temperature that livestock will perform the most efficiently and be the most comfortable. While livestock are out of their TMZs most of the time during the summer months, it means we need to be more cognizant of the potential for heat stress. Indicators of heat stress include panting, excessive slobbering, lack of coordination and trembling. Tips to help alleviate or prevent heat stress: - Provide cool, clean drinking water as often as possible. o Water prevents dehydration, and is the fastest way to lower body temperature. o A 1,250-pound steer will need to consume approximately 25 gallons of water per day when the weather is hot. o A 280-pound hog will need approximately 3 gallons of water a day. o A typical market goat or market lamb will need around 1.5 to 2.5 gallons of water a day. o All of these may vary depending on the size of the animal, effective temperature, and wool or hair amounts. - Rinse livestock down to lower body temperatures. o During down time on days that your project is not showing, rinsing them down for 10 to 15 minutes will help make them feel more comfortable. - Reduce Stress. o Try to clip and prep livestock as little as possible at the show. o Do not get them ready too early - try to gauge the amount of time needed to prepare. - Do not overcrowd livestock in pens or stalls. o Overcrowding reduces airflow and does not allow livestock to naturally dissipate their body heat. - Use fans and misters. o Airflow helps cool the area. o Fans and misters work well to increase evaporative cooling and to aid in making livestock more comfortable, but be careful because adding moisture can increase humidity and defeat the purpose. - Use as little bedding as possible. o Bedding will retain heat and reduce the animals' surface area. If you ever have a question about an animal that may be experiencing heat stress, contact a veterinarian, your project leader or your county agent. A lot of time and money have been committed to your livestock projects, and the last thing you want is your animal to not perform at the best of its ability or, even worse, to die.