Ronnie, 

After the two responses I saw, Sarcocystis and Toxoplasmosis, I had
some questions.

You did not describe what you saw in the muscle?  Cysts????  etc?

Were the goats in an area with a lot of barn cats?  Goats could
get Toxo by eating cat fecal contamination of food sources around
barns, and goats are such garbage guts, will eat cigarette butts out of
ashtrays (had a friend experience that story!). 
Did you look at brain, lymph nodes, and kidney sections also? 
Toxo might be a possibility and IHC can be done for positive identification.

Sarcocysts are giants by comparison to Toxo. 

Gayle Callis