Over the past two weeks, we’ve seen some really amazing pathologies in the many species we’ve necropsied. We saw emphysematous cystitis (gas in the bladder wall) in a foal, a gastric dilatation and volvulus (when the stomach twists) in a dog, and severe pneumonia in cows and sheep. I could go on and on about all of the things that I’ve found amazing, which would probably gross most people out, but I want to talk about my loon!
First of all, how amazing is it that I get to see the inside of a loon? I’ve always loved listening to their soothing coo echoing out over the water and seeing them peacefully bobbing on a lake. As sad as it was to see one dead, we can learn a lot from how this animal’s death is related to how we change things for these animals.
What amazed me just looking at this bird was how big it was. I thought loons were little ducks, but they’re actually quite sizable, probably a little bigger than my beagle! Immediately we noticed how emaciated the bird was by observing its severe muscle atrophy. When we opened her up, we immediately noticed the complete lack of fat under her skin, to the point where you could see every feather follicle from the inside. Lead toxicity was the suspected cause of death in her case, and this clinical picture is unfortunately the norm for birds who have accidentally ingested lead.
As I removed her keel bone, I immediately noticed that I was peeling some chunky material from one of her air sacs. After further inspection, I realized all of her air sacs were covered in white plaques and filled with a yellow-green material. She had severe air sacculitis, which is most likely a result of immune compromise secondary to lead poisoning. My favorite lesion was a 10-cm diameter plaque in one of her air sacs that was the perfect picture of what an aspergillosis infection looks like. You know bread mold? Well, picture that filling the space where a loon should have air. It was an incredible lesion, and one of those times I could immediately put a picture to something we had learned about in class.
My excitement aside, we’re waiting on toxicology of her liver to come back to confirm lead toxicity. This sadly is a common cause of death in birds, due to lead being in their food sources. For example, this could be birds of prey that ate the carcass of something shot with lead, or a duck that ate a fish that had been hooked at some point. As a point of learning, if you have any lead tackle or ammunition, please switch to a more environmentally safe alternative and help save our birds!