Why would a Horse Lose Weight during Hot Weather?

Find out why some horses lose weight when the temperature rises.
Share
Favorite
Close

No account yet? Register

ADVERTISEMENT

Several factors influence how much energy it takes to maintain normal body temperature. Air temperature, humidity, wind velocity, solar radiation, and precipitation are all factors that affect how much energy is expended to maintain normal temperature for animals that are exposed to these elements.

We know that horses use more calories to stay warm in the winter, as cold weather has been estimated to increase horses' digestible energy (DE) requirements about 2.5% for each degree Celsius below -10° (14° Fahrenheit) per the 2007 National Research Council's Nutrient Requirements of Horses. The “thermal neutral zone” for horses is estimated to be from about 5°C/40°F (lower critical temperature) to 25°C/77°F (upper critical temperature).

It takes horses about 21 days to adjust to a higher or lower ambient temperature, with most of the adjustment taking place in 10 to 14 days and more adjustment taking place over a longer time.

We do not have good horse data for the impact of conditions above the upper critical temperature. If we assume even a 0.5% increase in DE for each degree C above the upper critical temperature (a fairly conservative estimate based on known cold weather changes and other species information), and if the ambient temperature is 35°C/95°F, the horse would need 5% more DE at the higher temperature just to maintain body weight. And as most horses do not necessarily eat more at higher temperatures (some actually consume less food), the higher DE requirement for just maintenance might be expected to produce weight loss just from the extra energy required to keep cool

Create a free account with TheHorse.com to view this content.

TheHorse.com is home to thousands of free articles about horse health care. In order to access some of our exclusive free content, you must be signed into TheHorse.com.

Start your free account today!

Already have an account?
and continue reading.

Share

Written by:

Roy A. Johnson, MS, is an equine technology manager for Cargill Animal Nutrition. In his role, he is responsibile for the development of horse feeds for U.S. business, including feeds for Nutrena, ACCO, Agway, and private label brands. A former professional horse trainer, farm manager, and horse judging coach, Johnson was an assistant professor in the Agricultural Production Division at the University of Minnesota-Wasecae before joining Cargill. Johnson has also participated in a successful Thoroughbred racing partnership._x000D_

Related Articles

Stay on top of the most recent Horse Health news with

FREE weekly newsletters from TheHorse.com

Sponsored Content

Weekly Poll

sponsored by:

When do you vaccinate your horse?
378 votes · 378 answers

Readers’ Most Popular

Sign In

Don’t have an account? Register for a FREE account here.

Need to update your account?

You need to be logged in to fill out this form

Create a free account with TheHorse.com!