Understanding the Goat Digestive System Avoids Tragedies
How many stomachs does a goat have? And why?
Reading Time: 4 minutes
Throw out that old wive’s tale that goats can eat anything. Most health problems start within the goat digestive system. Ruminate on that!
Aside from kidding complications or losses due to goat predators, many fatalities among new goat owners stem from a lack of understanding about goat anatomy. Specifically, the goat rumen and bacterial balance within. Learning how rumens work and how to help maintain that healthy balance can prevent terrifying problems such as goat bloat and enterotoxemia.
How many stomachs does a goat have? Four, just as cows do. Food first travels from the mouth into the rumen, then to the reticulum, omasum, and finally the abomasum before entering the intestines.
Both the reticulum and rumen combine to serve as the part of the goat digestive system where most microbial digestion occurs.
When a kid is born, the rumen, reticulum, and omasum are undeveloped to allow absorption of antibodies from colostrum. Milk then travels to the abomasum, where rennet (yes, the type used to coagulate cheese), a collection of enzymes, curdles casein in the mother’s milk. Curdling allows the milk to stay longer in the intestines, where babies can better absorb the nutrients within. As the kid matures and starts eating fibrous plant material, microbes become established.
Microbial action serves several purposes within the goat digestive system: it breaks down solid food, it synthesizes B vitamins, and it helps create heat for homeostasis.
While our parents may have told us to completely chew our food, goats and other ruminants eat quickly, a behavior that developed in the wild where the areas containing the best food may also be in the most dangerous locations. Once safe and rested, ruminants then regurgitate the food and chew it again as cud before it travels back into the rumen to be broken down further.
A goat’s rumen is located on the left-hand side. Many people who have kept bottle babies recognize this, as they have often held a kid upright while patting the bulging area to release gas and avoid bloat.
Omasum and Abomasum
Within the omasum, further digestion occurs, including absorption of water and inorganic minerals. Then food travels to the abomasum, where acidic digestion performs the same function that it would within a human’s single stomach, breaking down proteins. Food and the microbes produced within the reticulo-rumen then undergo digestion within the small intestine before passing to the large intestine and out the body.
Acidosis and Enterotoxemia
The goat digestive system needs specific microbes, in a specific balance. And tragedies happen if that balance upsets.
In order to keep bacteria levels high, goats need a diet high in crude fiber. If healthy, they eat enough fiber to keep bacteria high enough to metabolize potential toxins like tannins found in oak leaves. That is why you will see them gnawing on bark or twigs, which may seem otherwise inedible. Goats often forage for enough crude fiber, or they consume it from eating hay with thick stems, but they may not receive enough of this fiber if they have high-grain diets.
Acidosis is when the rumen’s pH goes from too low, often from a lack of bacterial action. An overload of carbohydrates can cause it. Acidosis in goats, also called lactic acidosis or toxic ingestion, can be either acute (sudden, from a sudden change in feed) or chronic (from a consistent supply of the wrong feed.)
Highly lethal enterotoxemia in goats, also called overeating disease or pulpy kidney disease, isn’t directly caused by overeating. It’s caused by the toxin created when bacteria Clostridium perfringens types C and D flourish, and they can only flourish under certain conditions such as elevated starch and sugar within the goat stomach. Avoid enterotoxemia in goats by providing the CDT toxoid according to the correct goat vaccination schedule. Though the CDT vaccine protects against both Clostridium perfringens and Clostridium tetani within one shot, a Clostridium C&D antitoxin and a tetanus antitoxin for goats are two separate products and cannot be interchanged to treat other clostridial diseases in goats.
Goat bloat (ruminal tympany), another problem when the goat digestive system is unbalanced, kills quickly. Sudden access to excess grain, or overconsumption of lush or frozen legumes such as alfalfa and clover, can cause frothy bloat while esophageal blockage that prevents belching can cause free gas bloat. Another cause, sudden food changes, upsets the rumen’s bacterial balance so much that it cannot effectively digest. Recommended goat bloat treatment includes addressing the cause (dislodging an obstruction), massaging the rumen area, or drenching with mineral oil for frothy bloat. However, do not administer the mineral oil without a feeding tube, as this can drain oil into the lungs.
If excess acid causes bloat, acidosis, and enterotoxemia, should you provide an alkaline product for goats to eat during moments of discomfort? That’s a palliative method used by many people, providing a tub of baking soda for goats. But Karen Kopf, of Kopf Canyon Ranch, says it’s not necessary or recommended.
“Sodium Bicarbonate (NaHCO3 — baking soda), an acid buffering agent, is a source of sodium — or salt,” says Karen. “Goats naturally produce buffering agents to regulate their rumens in their saliva and may exceed the need for buffering seeking salt, upsetting the balance. A goat’s appetite for salt is the limiting factor in mineral uptake, which determines the number of trace minerals a goat ingests. The salt in minerals is NaCl, which is non-buffering. If their need for salt is met, they will not seek salt from their trace minerals.”
That isn’t to say you shouldn’t keep a supply of baking soda for goats. Experts at goats.extension.org recommend administering sodium bicarbonate by mouth to neutralize acute acidosis. They also recommend magnesium hydroxide (Milk of Magnesia) or magnesium oxide. If a goat suffers from acidosis, they may soon suffer from polioencephalomalacia (thiamin deficiency). If treating goat acidosis, contact a veterinarian in case severe complications occur. Provide probiotics after a rumen crisis to replace those beneficial microbes as soon as possible.
Providing adequate, fibrous hay for goats, woody browse, or feeding whole, un-hulled grains instead of finely ground grain can prevent acidosis. Administering CDT shots for goats prevents enterotoxemia. Keeping the goat digestive system healthy is one basic step toward responsible and caring husbandry.
Originally published in the Goat Journal 2020 special subscriber issue — Goat Health, From Head to Hoof — and regularly vetted for accuracy.