Hey I always heard that once you get a dog spayed that they will gain weight, I have a rat terrier dog who is 4 years old and her name is Prissy and she was spayed in september and she has always been really skinny and the vet said that when I get her spayed she would gain weight but she hasnt gained any weight, she is so small . She doesnt seem to care about eating. She will go a couple days or so and not eat. I always heard people say that when there dog got spayed that it started eating alot and gained weight. So I am wondering if they may be something wrong with my dog. Any suggestions, and does spaying really do usually cause a dog to gain weight.