When a horse begins to sweat, fluids from his bloodstream pass through the sweat glands to emerge onto the surface of the skin. But as he continues sweating, the blood left behind becomes more concentrated. Long before the blood becomes too dense for the heart to pump it, other fluid reserves within the body are drawn into the bloodstream to keep the critical red cells moving as the horse works. Which parts of the body are the primary sources for the backup fluid?
Answer: a. and b. The gastrointestinal tract, especially the cecum0 and large intestine, is an important reservoir of fluids that are rich in nutrients and electrolytes from the horse’s feed. The blood will also draw a lot of fluid from the spaces between his cells. If the horse continues sweating to the point where
these reserves are running low, his body will start to draw fluid from inside of his cells. At this point, however, he is becoming seriously dehydrated. Horses who sweat too long without replenishing their fluids can experience a number of health issues, ranging from impaction colic to tying up. Fortunately, most horses
a. the interstitial spaces, the areas between the body cells b. the gastrointestinal tract c. the lymphatic system d. the lungs
need nothing more than rest and access to fresh water to make a complete recovery from an intense workout. A significantly dehydrated horse may require several days of rest and drinking, and a veterinarian may need to rehydrate the horse intravenously or through nasogastric intubation.