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  Discussion on Foal with Enlarged Thyroid
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New Member:
Whoswho

Posted on Friday, Sep 13, 2002 - 12:23 pm:

My precocious filly (Perch/Tbred) is now 4 months old. She was born with an enlarged thyroid (also underslung jaw), but normal thyroid levels. One vet thinks it was caused by too much iodine in the mare's diet (she was on Source, MarePlus and a mineral salt lick), another thinks it was caused by the stallion (although none of his other offspring have had this). It is quite large - maybe 4" long, and wrapping around the throat 4+". My vet wants it taken out, but the surgeons say it is a difficult and risky surgery. Are there any other treatments to try to minimize the size of it? If left untouched, what problems can/will it cause later on in life? She is a very active, intelligent baby; her appetite and attitude are great.
TIA
Pam, CindyLouWho & Who's Who (Pnut)
Moderator:
DrO

Posted on Saturday, Sep 14, 2002 - 3:05 pm:

What were the amounts of iodine in each of your supplements and how much were you feeding for how long?

Goiters in newborns have been reported with the use of Source in combination with other iodine containing products. There are no health problems associated with the enlarged thyroid and I believe in time it will be less noticable as the foal grows. Partial removal of thyroids have been successfully accomplished uf you want a more cosmetic appearance.
DrO
Member:
Whoswho

Posted on Monday, Sep 16, 2002 - 7:23 am:

Hi DrO,
The mare (1800+# pre-pregnancy) was getting 1 oz. Source (.06 - .1%), 2 oz. MarePlus (300 ppm) and free access to a mineral salt lick (70?700? ppm) throughout her pregnancy. Sounds like a lot, doesn't it?! What would have been an acceptable amount?
I am more concerned with my baby's future health than appearance; I mean when she gets old... will she be looking at problems breathing? I would like to do Combined Driving and some lower level Dressage with her... will it affect her being able to *come round* and *onto the bit*?
I am reluctant to risk her life in a dangerous procedure if there are truly no health issues to worry about later on.
Thanks
Pam
Moderator:
DrO

Posted on Monday, Sep 16, 2002 - 7:57 am:

The range for iodine and other minerals in the diet is found at » Care for Horses » Nutrition » Minerals and Nutrition. But even without doing the math on the known amounts (I do not know how much she was getting from the salt lick) it is a lot of iodine.

Not being able to see the goiter I am unable to give much opinion on how it might effect her ability to flex the poll but it is unlikely to cause breathing difficulty.
DrO
Member:
Whoswho

Posted on Monday, Sep 16, 2002 - 8:20 am:

I took a look at the iodine guidelines... wow! She sure was getting a LOT! The baby has no problem flexing at the poll right now... is it safe to assume that the condition will get no worse as she grows?
Pam, feeling rather foolish as I have always researched anything new I fed Cindy, unless it was vet-recommended... my vet was the one who put her on MarePlus, in addition to the Source. :-\
Moderator:
DrO

Posted on Tuesday, Sep 17, 2002 - 2:53 am:

Pamel I went ahead and did the math and making the assumption that a mare this size eats 36 lbs of feed (dry matter basis) a day that before the salt lick is figured in she is getting around 2.5 ppm iodine. This is 25 times the recommended minimum and about 1/2 the amount listed as toxic.
How careful was your measuring and how much salt does this mare consume. Don't misunderstand me, even at 1/2 the usual amount considered toxic this is way too much and almost no doubt the cause of the fillys problems, I am just wondering how good that 5 ppm toxic number is.
DrO
Member:
Whoswho

Posted on Tuesday, Sep 17, 2002 - 7:53 am:

Yikes! I believe my measuring was pretty accurate, only because each supplement has its own measurer and she was getting exactly one measure of each. She was consuming about 2 salt licks/month toward the end. She was getting 5# of grain a day and possibly 40# of timothy/alfalfa hay. She now has a plain salt lick; the only supplement she is on now is E/Selinium and she gets 1/2 - 3/4 dose because of the alfalfa in her hay.
An interesting side note... since I got her, she always had white matter in the corners of her eyes. Within 2 days of being taken off the Source, the white *goobers* disappeared.
Pam
Moderator:
DrO

Posted on Wednesday, Sep 18, 2002 - 7:19 am:

Was the measure level or heaped? Alfalfa is also a richer source of iodine than grass hay which I used in my calculations. You are making a mistake removing mineral salt from the diet as many important micro minerals are in it, perhaps loose added to the feed daily would be better. It is the Source that needs removing from the diet.

Lets see 2 salt blocks 20 lbs each in a month that are .007% iodine equals 1300 mg over a month that is 500 kg dry matter.....there it is the extra 2 or 3 ppm of iodine to push you over the 5ppm limit.
DrO
Member:
Whoswho

Posted on Wednesday, Sep 18, 2002 - 7:50 am:

Yikes again! The measures were level. The salt blocks were the small 2# ones. I removed all supplements because the baby started eating Mom's grain at 1 week and could reach the salt lick at 2 weeks. (Precocious!) She had digestive problems at the beginning, but we were attributing that to ulcers... while outside she would eat grass like there was no tomorrow, then come in, have a bowel movement, and be very uncomfortable. Can I keep the plain salt lick and add loose mineral salt to the grain? They both love their salt lick. Baby will be weaned at the beginning of October... should she get mineral salt on her own too?
Pam
Moderator:
DrO

Posted on Thursday, Sep 19, 2002 - 6:19 am:

Oh the small ones, well that's different that lowers you to about 3ppm in my very rough calculations. That amount of salt is fine and you can just continue using the blocks. I would not use the plain salt, remember too little iodine is as bad as too much. Just remove the Source and you will be fine.
DrO
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