Loose droppings: stress or diet?

Loose droppings aren’t nice: anything from “cow pats” to watery slurry means dirty horses and difficult mucking out. In some horses it is rare. In others, just the stress of travel and competition can set them off. In any case, loose droppings are a sign that something’s not right.

Regular loose droppings might mean your horse ahs a particular susceptibility to stress, but sudden onset of a smelly and watery projectile diarrhoea, accompanied by darkened mucous membranes, may be indicative of unexpected stress or disease.

The horse’s digestive system is huge and when full, accounts for about 15% of its total weight. The small and large intestines account for the majority, with the large intestine holding 100 litres of food and water at any one time.

Anything affecting the digestive system affects the general health of the horse. The whole tract is populated with bacteria and other microbes, particularly the hindgut. Upsetting the balance is what causes loose droppings.

In the small intestine, upsetting the balance through stress allows pathogenic bugs such as salmonella to proliferate. In stressed horses, probiotics or prebiotics are sometimes recommended to prevent this “takeover”. Some people report good results, making probiotics or prebiotics a good insurance policy if you have a stressy horse. However, there is actually little scientific proof that they really do work.

The more food you give, the faster it passes through. Horses that are loose on 18lb of hard food per day often improve when the level is dropped to 14lb. In effect what happens here is that more forage is eaten, and this is essential for a healthy digestive system. It acts to “stem the flow”.

Any starch and sugar not digested and absorbed in the small intestine passes undigested into the hindgut and disrupts its normal function. Loose droppings are an early sign that things are wrong. Do something about it before it turns into colic, laminitis or tying up.

Possible causes:

• Check temperature and pulse for signs of fever or illness
• Recent use of antibiotics: these disrupt the internal microbial balance
• Check that your worming programme is up to date
• Think back as to recent changes that may have caused a change in the amount or type of food consumed, i.e. turnout on to a new paddock with more grass or a sudden spurt of grass growth. Recent hard work over and above the horse’s stage of fitness. A new batch of hay or haylage that the horse isn’t eating as well. A sudden weather change such as unexpected frost or thunderstorms.
• Feed to prevent an overload of starch and sugar
• Never give more than 2kg of hard feed at a time
• In high-risk horses, opt for low-starch feeds. Cubes are always lower in starch than mixes
• Of all the starches, starch from maize (corn) is the slowest digested in the small intestine and is the one most likely to overflow into the large intestine. Be wary of feeding large quantities of high-maize diets.
• This feed feature first appeared in Horse& Hound (16 September 2004)