Lots of animals eat feces. There's still a lot of nutrition left.
Do a google search on drinking urine. Quite a few folks do it for sexual kicks. Others for "health" reasons.
I knew a woman who was receiving alternative cancer treatment which consisted of injecting her own urine IM. True story. She was paying a lot of money for this too.
And, as someone pointed out, Premarin is made from horse urine.