Budgie anatomy-- what's normal to feel on throat/under lower mandible?

[GreenThing]

Yes, I am on the paranoia train with Percy, but I have to ask any budgie owners whose birds enjoy scritches: I've been giving Percy lots of head rubs, this molt, and a spot he really likes to be pet is the naked pink spot under his lower mandible. I've noticed there is like a hard, round protrusion in the hollow of his throat and assumed it was part of his anatomy (the trachea? thyroid area?). Has anyone else with touchy-feely budgies (or other little psittacines, I wouldn't imagine they are that different) noticed this? Is it a normal thing to feel?

I'm assuming (read: hoping, questions) that my vet would have noticed anything obviously amiss during the physical exam, but when reading about budgie anatomy I was shocked to see multiple studies that indicated certain green vegetables have directly contributed to thyroid issues (including goiter) in budgies (usually when there isn't enough supplementation). Iodine-binding goitrogens include cruciferous vegetables (especially broccoli, but also Percy's favorite vegetable-- dandelion greens). I know Harrison's contains iodine supplement (I know sea kelp is high in iodine), and maybe it is more than enough to offset goitrogens, but this has set off all of the alarm bells in my head. This avian medicine entry from UF (it's old, 2003, I don't think iodine deficiency is as prevalent with pelleted diets) would be upsetting even if I wasn't headed to the vet:

An inadequate level of iodine in the diet leads to a lack of available iodine in the thyroid glands. Iodine is needed for the production of thyroxine. [...] Hyperplasia of the thyroid gland is a response to the body's need to produce more thyroxine. With sustained iodine deficiency, the signals continue to stimulate epithelial cell proliferation and produce thyroid enlargement.

Goitrogenic substances act by blocking the production of thyroxine, even though adequate levels of iodine are present.

Crop distension. And one of his behaviors that worried me lately were little squeaking sounds he would make if he was bending over unusually far (I have some deepish forage cups) to eat.

 

[GreenThing]

Warning for that first link, it mentions subjects that were sadly euthanized and has necropsy photos, I hadn't read it in full when I posted, sorry.

 

[GreenThing]

SORRY SORRY to reply to my own post again, my edit expired: just wanted to add that I read the really wonderful inch by inch explanation of avian anatomy pinned at the top of this subforum, and it was so helpful:

Since the neck forms an "S" curve, it protrudes forward in the front, above the level of the crop. Often, this may be mistaken for a tumor or abnormality in the neck, especially when the crop is empty and the bird is sitting comfortably. Because the neck has more vertebrae than a human's and mammal's, the avian neck is extremely flexible, mobile and strong.

That might explain what I'm feeling when I pet him (I could not find that detail ANYWHERE, bless the vet who wrote that article), and I know thyroid glands are deeper in the body and would present swelling, not a hard lump, but I'm still putting thyroid problems on my list of things to at least mention to the vet. That area IS, if marginally, more swollen than is normal for him, and I'm watching his breathing very closely.

 

[Tanya]

The crop feels like either a hollow area at the front where the neck joins his body if it's empty, or it feels like a tiny stretched balloon full of oatmeal if the bird just ate. Be gentle with a full crop. The crop doesn't move much at all of you touch it, though the bird will usually pull away if you do. (Imagine someone pushing on your stomach right after you ate a big meal and it probably a similar experience for them.)

If what you're feeling is more like a tiny hard lump right under the chin that moves rapidly up and down against your finger, it could be his tongue bones. Humans don't have tongue bones but most birds do. It helps them to manipulate food, like a tiny finger in their mouth, since very few birds have feet adapted to grasping and holding like a parrot. The fancy name for these bones is the "hyoid apparatus" and I learned about it when Rhubarb started insisting on chin scratches. It was such a weird feeling that I did a bunch of research until I realized it was her hyoid apparatus moving around while I was scritching her. She likes to mumble "good girl" when I do it, and in parrots the tongue bones are critical in helping them form the sounds of our human words since they don't have lips.

 

[Tanya]

The crop can be pretty hard if he recently ate. You could remove his food for a couple of hours and see if that changes the lump. If it gets softer or goes away, it is his very full little crop you were feeling.

 

[WillowQ]

You will feel their bony little necks, too. The neck is longer than you’d expect and held like an “S” shape. I feel the belly of the neck vertebrae “S” exactly as you described: a hard bump a bit under the lower mandible. Right under the beak you can feel the left and right sides of the lower jaw. Then the neck curves towards the back and then you feel the bump of neck vertebrae. If you follow that, the crop is lower down, below the necklace area of a budgie or in a Quaker’s bib.

I am a zoologist and am happy to answer other bird anatomy questions. Human and bird bodies have many funny quirks if we examine ourselves closely. For example, I was alarmed that my belly was slightly asymmetrical. My dr took a look and pointed out that there are different organs on the left and right sides of the human belly.

 

[GreenThing]

Thank you for your replies! I think it was indeed the hyoid apparatus (I think the crop would be much lower down than any area I'd touch while petting?).

While I'm glad I read about goitrogens for future reference, I learned from a blood panel that it is sadly most likely that Percy has renal issues-- possibly kidney failure. He had very alarmingly elevated uric acid levels and is now getting two medications by mouth and subcutaneous fluids. Just appreciating every moment I have with him, now.

I reread my first post about his polyuria on this forum, and I was 1) immediately worried about renal issues and 2) concerned that my avian vet didn't want to do a blood test. I'm going to have a hard time not hating myself if I lose him.

 

[Tanya]

We had a long go of giving allopurinol to Rhubarb every twelve hours for two years after she nearly died from rapid onset renal failure. It was a scary time for sure.

 

[GreenThing]

Even though tumors and renal issues are reportedly common in budgies, the vet and tech were surprised to see his uric acid levels so high with 1) no signs of metal poisoning and 2) him being only two years old. They were so surprised I had to show them pics of him with baby bars to prove I knew his age. They still don't know the cause and having researched renal issues more specifically, I get it. It's hard to narrow down (at least, without tests too invasive for a small bird). Did you ever find out the source of poor Rhubarb's issues?

They're intending to do another blood draw when his course of meds is done, and I don't think I can watch this time. They do a nail clip for the little birds, which I've seen not recommended in vet texts and by vets, but I can also see why they might consider it safer for small birds. I might post about that specifically.