A Goat’s Stomach: Surprising Facts and Why a Goat Has More Than One
Have you ever wondered about how a goat’s stomach works? Many new goatkeepers don’t actually realize quite how amazing a goat’s stomach is. But, in reality, your goat’s stomach is an evolutionary work of art, and it’s truly amazing how the goat’s stomach works! With this thought in mind, today, we’re looking at some key questions you may have wondered, including how many stomachs a goat has, how a goat’s stomach works, and the like.
How Many Stomachs Does a Goat Have?
As a ruminant, a goat only has a single stomach – but we often say that they have “four stomachs” due to their stomach’s four-chambered design. The goat’s “four stomachs” are the reticulum, the rumen, the omasum and the abomasum.
Do Some Goats Have More Stomach Chambers than Other Breeds?
All goats have a four-chambered stomach, and this is the same between all species of goats. The ruminant bioplan evolved around 50 million years ago, so you would have to look farther back than this to find ancestors of the goat that did not have multiple stomach chambers.
However, it’s worth noting that the exact size of the stomach will vary between goats of different ages, breeds, and the like. Furthermore, a heavily pregnant doe or nanny will have a smaller stomach capacity than other animals since the growing goat kids can place pressure on her stomach.
What is the Purpose of Having Multiple Stomach Chambers?
The purpose of having multiple stomach chambers is simple: it allows goats – and other ruminants – to make much better use of rough, coarse, and nutritionally low feeds. If you’ve ever seen a goat munching happily on a twig or a little bit of fresh barley straw, you’ll see what we mean here!
As such, ruminants are much more efficient at using poor forages. In fact, without their rumens and advanced stomach structure, it’s unlikely that ruminants and goats would be able to survive in so many rough, seemingly inhospitable terrains. It’s worth noting, though, that a lot of this success is owed to the immense population of microbes living within the rumen; as such, as birth, a goat still has a sterile rumen, and so the rumen does not function until the goat is a little older. That’s why you cannot hope to wean a goat kid until its rumen is fully developed; it is immature and ineffective at birth!
After food has passed through the stomach, it’s already more digested than in many other herbivorous and omnivorous species. Thereafter, the intestines help digest and absorb any remaining minerals, allowing goats to make use of poor forages to the best of their abilities.
How do Goats Compare to Other Animals?
Goats are ruminants, alongside many other common herbivorous species such as cattle, deer, and sheep. The ruminant is largely defined by its incredibly well-adapted stomach structure, which makes it highly efficient at breaking down and digesting highly coarse, fibrous, and hard-to-digest foods, such as grasses, that many other species struggle with.
As we’ve already mentioned, the ruminant’s stomach structure has four chambers: the reticulum, the rumen, the omasum, and the abomasum. This differs from most other animals, where the stomach structure is much simpler; for example, our own stomach is just a single large “sac” where acids begin to break down our food.
The four chambers of the goat’s stomach each carry out a different role. The reticulum stores food after it’s swallowed (we’ll look at this in a minute). The rumen acts as a fermentation vat and is by far the largest part of the stomach, where a massive community of bacteria ferment the forage and convert it into more easily digestible materials (VFAs – volatile fatty acids). Next, the omasum absorbs water from the feed. Finally, the food then passes into the abomasum (often called the “true stomach” where standard digestion through hydrochloric acid and digestive enzymes takes place on the already-broken-down matter.
In contrast, in other animals, the stomach process is far simpler and mainly relies on digestive enzymes and acids. As such, by the time plant matter reaches the ruminant’s true stomach, it’s already much more broken down and easily digestible.
By contrast, species such as horses work differently. Horses are hindgut fermenters; they still ferment their food to get the most from it; however, this occurs at the end of their digestive tract in an enlarged cecum. As such, they are much less able to make use of roughages than a ruminant.
Chewing the Cud
It’s worth considering that the goat’s ruminant digestive system is very different from our own, since food doesn’t stay solely in the stomach before passing along the rest of the digestive tract. In fact, your goat will regurgitate some of their newly-eaten food when they feel comfortable and happy to re-chew it. This process is called chewing the cud.
Some people mistakenly believe that non-ruminants also chew the cud; for example, Chris Packham from the BBC once claimed that horses and cattle both chew the cud. However, in reality, only ruminants are able to actively chew their cud. Since horses are actually classed as hindgut fermenters, they do not have the ability to chew their cud.
If you’ve ever wondered, how many stomachs does a goat have, the answer is actually a little more complex than you may have realized. Indeed, by definition, a goat only has a single stomach. However, we often claim that goats and other ruminants have four stomachs since their four-chambered stomach design means each section does something a little bit different.
It really is quite amazing to see a goat in action, digesting roughages and course leaves that look simply inedible to us. However, as with other ruminant species, they can do this thanks to their “four stomachs.” Hopefully, today’s guide will have helped you understand more about the goat’s four-chambered stomach, how this works, and what this means for their health and wellbeing.