first time goat owner

I have a rescued weather male, 4-5yrs old, Nigerian cross I believe. He seems to urinate very frequently. No straining, and stream is steady. A few nights ago I saw a spot where he had urinated and it looked dark/ bright red in color. So I did a urinalysis on him (I work in lab). The collection...

I have two young goats who need there second doses but am unsure of where to get a needle or what type to get and how much to dose also where do I inject it Thank you