Weight Gain Even Though Less Appetite?

[christinepi]

Tracker, after a recent change in diet and having vomited up splinters from a cow hoof got really weird about food for ca 2 weeks. He'd only eat ca 60-70% of his regular portions, and only when I begged him, and at really odd times. The only thing that he ate with unchanged enthusiasm were his treats (bully sticks, canned dog food filled frozen marrow bones, raw eggs). Anyway, I took him to the vet; she did a urinalysis, stool sample, full blood panel, x-ray: all normal, except that he's on the low end of normal for thyroid even for a Greyhound. His energy level is better than ever, oddly, and in every other way his behavior has been normal. He's 4.5 years old.

 

Lo and behold, as soon as we got back from the vet he started eating like a pig, and is back to a normal schedule. Of course. And obviously, after hearing that except for his low thyroid everything else was normal I'm greatly relieved, despite the $368 it cost me.

 

Two questions:

 

1. He gained weight (he went from 73 to 75lbs since he last saw the vet in May). So despite the slowed down appetite he got heavier. (I changed his kibble from TOTW to Evo red meat ca 3 weeks before this whole weird behavior started. Could it be that he gained this weight in 3 weeks just from having shifted to Evo?) Of course, he could have started gaining weight since May, who knows, which in and of itself might be an indication that his thyroid is off.

 

2. The vet only checked T4. I know from checking online in the past that dogs shouldn't be put on thyroid drugs without doing a full thyroid panel PLUS to send some blood to (I believe) University of Minnesota, because they're the only ones who check one particular thyroid detail? Do I have this right?

[GeorgeofNE]

I've had my dog weigh different amounts putting him on the scale two or three times at the vet in the same visit. I would not be concerned over a 2 pound difference from May to August. He might have gained weight, or their scale might be off (or have been off in May).

[Batmom]

Michigan State University . Here are there FAQs: http://www.dcpah.msu...roid_Canine.php . I recommend the premium profile, which includes fT4ed and TSH . I would also recommend checking the box for endocrinologist's interpretation.

 

Edited because I can't read. I wouldn't be concerned about 2 lbs either -- that could be vet's scale as GeorgeofNE notes, or difference in food. If you feel he shouldn't gain more, then cut his food back a little.

Edited August 15, 2011 by Batmom

[greyhead]

T4 drops an atom and turns into T3. When T4 is low, the level of T3 can increase. This has been demonstrated in humans, but I don't believe it has been studied in dogs. Since we're both mammals, it may be true for dogs too. In any case, T3 is the more biologically active of the two hormones; it's what actually gets the work done in the body. So if your dog's T4 has lowered, his energy may be higher because of possibly increased T3.

I'm kind of a thyroid geek. I posted a link to an article that discussed the above in an H&M thread some months ago -- like December-ish. If you like reading really scholarly stuff, I can dig it out for you.

 

I agree with the others that a 2-lb weight gain isn't super significant. But I'd keep an eye on things and retest later if the weight gain continues or he develops other symptoms. And although I'm fine with MSU thyroid panels, I don't have absolute faith in their interpretations for greyhounds. But there's no need to argue about that right now.

 

I wish everyone were as observant as you are. The changes in your dog's response to feeding are worth noting. Makes me wonder if that cow hoof could have transmitted worms, other parasites, or bacteria that have upset his natural gut balance. One of our dogs has showed behavioral changes like yours after those sorts of exposures. (Just a coincidence, I'm sure, but ours was hypothyroid. Hope nobody flogs me for saying so.) So I think you'd be right to keep observing.