They Ate What?
Many publications like to play to the competitive streak that many veterinarians have. Some veterinary journals will regularly publish a photo of a particularly interesting or unusual case with the question: What’s your diagnosis? in bold print. Practically no vet can resist at least a glance at the case history and lab report summaries.
I knew it was a case of eosinophilic granuloma, you sometimes get to think smugly. Other times you think, how the heck did they figure that out?
X-ray contests are another form of veterinary competition and they often involve vets submitting radiographs from their practices of odd or practically unimaginable things found inside animals. I love these contests because it is just crazy to see the kinds of things dogs, cats, reptiles, and small mammals will consume. But, do you notice what’s missing from that list? Not ever is there a radiograph of a cow, a horse, a goat, or a llama in the mix. Never. That’s a total bummer for me.
Farm animals are mostly out of X-ray contests because they are just too big — the X-rays just don’t penetrate the large abdomen of a half-ton horse or a one-ton bull. Of course we radiograph horses’ limbs all the time looking for evidence of arthritis, fractures, soft tissue swelling, bone chips, and other musculoskeletal things.
Less frequently, I will take radiographs of small ruminants and camelids. This is usually again of a limb, most commonly to evaluate the healing of a broken bone. Even more rare is a radiograph of a bovine. Fractures are rare and most farmers elect euthanasia rather than treatment.
But this doesn’t mean that farm animals don’t sometimes eat weird things.
We’ve talked before about hardware disease, when indiscriminate bovines slurp up metal wire or other debris found around the farm, and how this foreign material winds up literally poking them in the stomach. I’d love to see a radiograph of a case of hardware disease, but I never have, again, mostly due to the size of the patient and the limits of the X-ray beam (we want to create a diagnostic image, not fry a hole in the animal).
When a dog or cat swallows something metal, this is very easy to identify on a radiograph. Metal is radio-opaque, meaning it reflects all the rays that are projected at it, creating a very bright, distinct shape on the film.
What about the proverbial goat eating the tin can? Goats have the reputation of eating everything when in fact they mostly just taste everything and otherwise can be somewhat fussy eaters. But if I had a radiograph for every goat that I was suspicious of a bellyache, well, I bet I’d win my share of the X-ray contests. (Goat radiographs are rare in practice more from an economic point of view than size.)
Ironically, one thing that you might never guess a farm animal can have in its stomach is a hairball. Medically called a trichobezoar, these foreign objects are found occasionally in cattle from grooming. They are hardly ever a health issue, unlike hairballs in cats, and remain inert in a bovine’s digestive tract until found unexpectedly on necropsy. They can get quite large — I saw one in vet school the size of a cantaloupe. They tend to be round and are very light weight, completely unlike the slimy, gross surprises you find in your carpet after your cat left you a present in the middle of the night.
You would probably never see a hairball on a radiograph, either. Hair being pretty much the same density as other soft tissue, it would be very difficult to distinguish a glob of hair from other food particles in the digestive tract.
As for my hopes of ever winning a veterinary X-ray contest, I think my chances are pretty slim. Maybe I should stick with the What’s Your Diagnosis, although my recent string of luck with those has been pretty abysmal. They tend not to do repeat cases of eosinophilic granulomas very often.
Dr. Anna O'Brien