How do you know if your dog is not straight?

What do you mean by straight? Do you mean that the dog is not pure bred? If so, then the pedigree should show that. If there is no pedigree, then you cannot be sure. A dog, however, is primarily a pet and a companion. Sometimes inbreeding to produce a pure line produces a dog with severe problems. Mongrels are generally much healthier and happier animals provided they are loved and well cared for by their owners. If you mean 'straight' as opposed to 'gay', I never heard of a gay dog. Many dogs are highly sexed and will hump anything that stays still long enough, including other male dogs. That is the way they are and it doesn't mean anything because dogs are not human and human standards should not be applied to dogs.

LOL. I don't know how to answer this but this topic just reminded me of Legally Blond 2. Elle has a pet chihuahua who she thought was male all the while but the dog fell in love with a Rotweiler, I think who happens to be male too. It was funny but I think that the first poster was right. I don't think that there's any "gay" dogs. They just like to hump.