To clarify, I believe this thread is about the Humane Society of the United States (HSUS). At least, I assume it is about HSUS.
Firstly, I can't believe people are defending HSUS -- they are probably the most aggressive and well-funded anti-zoo organization in the United States. (Another anti-zoo organization is the ALDF). HSUS has stated that they are on a crusade to ban sex with animals in all U.S. states, and they are currently going from state to state to push their agenda. They are succeeding -- NH, VT, NV, TX and KY all have anti-zoo laws now.
While most organizations are anti-zoo, few go out of their way to do anti-zoo things -- HSUS is one of those organizations.
Secondly, I disagree with thebestguy. Spaying and neutering is morally wrong. The reason it is wrong is because it deprives an animal of his/her sexuality (non-human animals have a right to have their sex organs remain intact, just like humans). The fact that humans are not spayed/neutered, but other animals are, is wrong because it treats humans differently from other animal species. If humans are not castrated, then non-human animals shouldn't be either. And also, spaying/neutering is done without an animal's consent.
Overall, HSUS is not a good organization. There are good animal organizations out there, but HSUS isn't one of them.