The answer is Yes and No.
Many animal species routinely exhibit homosexual behaviour and even same-sex parenting. This includes higher mammals, like monkeys as well as less developed species, like reptiles. This behaviour, however is never at the exclusion of heterosexual behaviour. It is therefore wrong to say that homosexual animals are ‘born in the body of the wrong gender’ – an imagery sometimes used to describe homosexuality in humans.
In my practice I often observe animals (dogs in particular) behave sexually towards animals of the same sex. However, this behaviour appears to be more play/assertive/pleasure seeking behaviour. These are not long term relationships, if you know what I mean.
So are animals ‘gay’? I suppose a term ‘occasionally bisexual’ would be better suited. Would they vote for Barak Obama? I think the answer would be yes – and that’s a non-Veterinary view.