I love small ruminants. These little guys (and sometimes not so little when a large Suffolk ram can push more than 200 pounds) are just the coolest patients. But did you know that not all small ruminants are created equal? There are some pretty big differences between sheep and goats.
Although anatomically very similar, sheep and goats do not even share the same genus. Taxonomically speaking, sheep are Ovis aries (the adjective “ovine” is used to describe something dealing with sheep, such as the respiratory disease ovine progressive pneumonia, or OPP), and goats are Capra hircus (again, the adjective “caprine” means goat, as in the goat disease caprine arthritis and encephalitis, or CAE). Sheep have 54 chromosomes and goats have 60, a fun fact I challenge you to include in your dinner conversation.
Called small ruminants because they share similar digestive systems as cattle (four stomachs that utilize bacteria to ferment cellulose for energy), sheep and goats are much smaller in stature, but they still have differences between their natural eating behaviors. Sheep are technically grazers, meaning they prefer munching grass low to the ground. Goats, on the other hand, are known as browsers, meaning they often choose to select leaves, shrubs, vines, and weeds, often found at the tops of plants, higher off the ground.
This natural difference between these two animals is key when it comes to pasture management. Sheep have an overall better resistance to pasture parasites because they have evolved eating close to the ground, putting them in close contact with roundworms, tapeworms, and the like. Goats, in contrast, developed eating off the ground. With less contact with parasites in manure on the ground, goats have a less developed natural ability to resist parasitic infections. Goats overall are more susceptible to devastating parasitic infections than sheep if forced to graze directly off the ground.
Another difference between goats and sheep is their flock behavior. Goats tend to be much more independent and curious than sheep, who adhere tightly to flock mentality and can appear aloof to humans. This difference often makes people assume sheep are less intelligent than goats and, I won’t lie, I’ve fallen to using this label as well. However, I’ve known a few cases where a sheep is raised on its own in a more “pet” setting and I’ve noticed those individuals are much more inquisitive and interactive than their flock-bound brethren.
Phenotypically, there are some breeds of sheep and goats that look very similar. One give-away to tell the difference is the tail position: A goat’s tail is frequently held up vertically while a sheep tail hangs down. In general, a sheep grows wool while a goat grows hair, but there are breeds of sheep called “hair sheep” that developed in the Caribbean with coats that are more hair-like and actually shed seasonally, negating the need for shearing.
If you ever get into the position where you’ve made a goat or sheep angry, here’s one last difference that might be useful to know. Rams (male sheep), when aggressive, will butt head-on while bucks (male goats) will rear up and come down with their heads. Believe me, you do not want to be on the receiving end of either one of those heads!
To wrap up this topic, let’s discuss briefly small ruminant diseases. Sheep and goats share many common bacteria, viruses, and parasites. Indeed, respiratory disease, bacterial foot disease, and diarrheal diseases are common between the two genera. But there are some diseases specific to each animal, such as OPP for sheep and CAE for goats, which I mentioned earlier. Other management problems like urinary stones are similar between the two animals as well.
So there you have it: the down low on the coolest little rumination machines on the farm.
Dr. Anna O’Brien