With Halloween approaching and spooky décor occupying many porches, I’m reminded of skeletons and inevitably get the bone song stuck in my head. You know how it goes: “The hand bone’s connected to the arm bone. The arm bone’s connected to the. . . ” and so on (anatomical knowledge notwithstanding). On the farm, the “hand bone” corresponds to hooves, and every once in a while, livestock animals need an X-ray. That’s where I come in.
Radiographic imaging technology has advanced dramatically over the past 20 years. The veterinary community has grown from analog machines (loading film and developing it in a dark room) to digital (linking to a laptop and within minutes getting a nice, crisp image that you can also manipulate with contrast, zoom or backlighting). Machines are smaller and lighter than they once were, too, making them easy to toss (carefully) into the back of a truck and haul into the barn.
So, what are the typical reasons an animal on the farm might need an X-ray? Reason No. 1: being a horse. Joking aside, without a doubt, horses are the grazing species most commonly radiographed. This is because of the plethora of conditions that plague their delicate legs and hooves. Laminitis, a common hoof disorder in horses where the structure called laminae that holds the bone suspended within the hoof capsule becomes inflamed, can cause the bone within the hoof to rotate or drop. X-rays are an integral part of the management and treatment of this condition, because they show how severely the bone has moved.
Evaluating osteoarthritis is another common reason to bring out the X-ray machine for a horse. A good X-ray of a knee or hock joint illuminates the delicate ridges of these complex joints and illustrate where they’ve been eroded by inflammation as well as wear and tear.
Dental radiographs are incredibly common in the small-animal clinic where cats and dogs have regular dental cleanings. Equine dental radiographs are becoming more common on the farm and provide a valuable diagnostic service when a horse has chronic issues with the teeth or elsewhere inside the mouth. A horse’s molars have very long roots, and infection within those deeper dental tissues are easily diagnosed on an X-ray of the area.
Of course, bone fractures are also a common reason to take a radiograph on the farm. In cases where a vet doesn’t know whether a joint is involved in the fracture, for example, or whether a hairline fracture exists somewhere in a leg, an X-ray helps.
Neonatal calves, crias, and kids and lambs sometimes also need radiographs—usually of a swollen leg joint that’s feared broken or infected. An X-ray can help a vet determine whether the joint space is involved and the severity of the damage. This also helps determine the chances of full recovery.
Aside from horse legs, other parts of the large bodies of our domesticated herbivores remain hidden when trying to snap an internal photo. The body of an adult horse or cow is quite literally so large that the X-ray beams have difficulty penetrating the deeper tissues; X-rays of their abdomens are almost useless except in a few situations, such as to check for sand in a horse’s abdomen or an enterolith (a stone in the intestine) that’s causing a blockage. Usually, if abdominal imaging is required on a large farm animal, an ultrasound is used instead.
In smaller farm animals, such as our small ruminants and crias, farm vets routinely refer the animals’ radiographic needs to the nearest small-animal clinic. More sophisticated equipment and better lighting create an ideal situation to get a good photo. Plus, it’s always fun to see the looks on people’s faces when you walk in the door of a vet’s office with a sheep in your arms. (Not that small-animal vets aren’t in on the joke—Veterinary Practice News has an annual contest for outlandish X-rays called “They Ate What?!“)
Because of a combination of economics and logistics, other farm animals rarely see a radiograph machine. Beef heifers out in the pasture can be a challenge to manage, and preserving expensive radiograph equipment usually outweighs getting too close to a large, fractious animal. The cost of an X-ray can also be prohibitive, depending on the suspected cause. Every once in a while, though, someone will ask to have a chicken X-rayed, typically in the case of a suspected egg bound hen. If you can hold her still, the X-ray will work just fine.