Ask the Nutritionist: Dr. Getty's Forum for Equine Nutrition
Welcome to my forum.
Here you will find more than 6 years of questions and my answers. It is searchable and offers a great deal of information.
Currently, I am discontinuing new questions. This may change in the future, but in the meantime, please know that It has been a true pleasure serving you.
Take a look at my Nutrition Library and Tips of the Month for a variety of answers on selected topics. Be sure to sign up for my monthly e-newsletter, Forage for Thought.
I also have a growing number of recordings on "Teleseminars on Nutrition Topics that Concern You" as well as the new, Spotlight on Equine Nutrition Series -- printed versions of favorite teleseminars.
And finally, look for my articles in a variety of local publications and online newsletters, as well as the Horse Journal, where I am the Contributing Nutrition Editor.
All the best,
Dr. Getty
Hi Jenni,
A lump that moves is generally a lipoma -- a fatty cyst that is generally not harmful. And, this may be what your husband has. But, to diagnose goiter in a horse requires blood work. Horses do need iodine and depending on what is being fed, he may already be getting enough. And goiter that is due to an iodine deficiency is really quite rare. Instead, it is often due to a hormonal imbalance (in particular, thyroid stimulating hormone). Or it can be an indication of a more serious problem.
So, I would not ignore this lump -- have it analyzed by your vet. His apparent "laziness" may be biomedical due to possible hypothyroidism. Don't second guess.
All the best,
Dr. Getty 
Where are you from? Bayfield, Colorado