NC summer temperatures have been hovering in the mid to upper 90’s for weeks with triple digit heat indexes and high humidity many days. During these periods of excessive heat, it is important for producers to take the necessary steps to minimize heat stress placed on swine as much as possible.

Many people do not realize that pigs do not have functional sweat glands. While other animals use their sweat glands to help cool their body temperatures, pigs use other strategies to reduce the amount of heat generated in their bodies.

Prolonged heat stress can lead to less than adequate feed conversion, decreased growth rate, and increased mortality. During daily swine observation, producers should look for symptoms of heat stress. Increased breathing rates or panting is the first and most noticeable symptom. Producers will also notice decreased pig activity and feed consumption as well as increased water consumption. All of these are part of a pig’s natural efforts to cool his body, but always seek the advice of your animal healthcare professional if you feel the pigs in your care need additional attention.

Here are a few steps to reduce the heat stress on pigs:

• Floor Space – Reduction in stocking density as much as possible will play a major role in heat stress reduction. Increasing the floor space for pigs gives them more space to lie down and they will have less contact with other pigs, thus giving them the opportunity to better dissipate heat.

• Ventilation – Adequate ventilation systems in great working order are vital to heat stress reduction. Systems should be checked often for mechanical failure and kept free of dust or any obstructions. Air movement over the pigs increases their rate of heat loss and will help decrease the humidity in the barns.

• Sprinkler Systems – Sprinklers are often used in barns as an effective supplemental source of cooling; however, they must be working properly according to manufacturer’s instructions and those of your animal healthcare professional. For example, sprinklers should not spray continuously or leak over the pigs as this will increase humidity. They are most effectively used by allowing time for the moisture to evaporate between periods of spraying.

• Water – Adequate availability of water is the most important factor in heat stress reduction. During periods of heat stress, pigs can increase their water intake by as much as six times their normal level. Waterers should be adjusted and functioning properly to provide the pigs with quality water whenever wanted.

By Max Knowles

Contributing columnist

Article was adapted from an article by Dr. Luiz Souza, Department of Animal Science, University of Minnesota. Max Knowles is an extension agent specializing in livestock with the Sampson County Cooperative Extension Service.