Logan's right. The only way to tell for sure if an animal has been spayed is to check for a scar. Also, finding out if an animal is pregnant or not, if she's not close to giving birth, requires xrays. That's expensive for most shelters.

Some shelters have vets that donate their time. Even then, most shelter vets just do a quick exam to make sure the animal is stable. Some get medications, some don't. Pretty sad, huh?

There have been animals that come into our clinic from the shelters with distemper! They vaccinate only with DA2PP, NOT RABIES and NOT for Bordatella. I always find that so strange. You'd think they'd want to protect them from the kennel cough the dogs ALWAYS go home with.