how old can a dog mate..

Question
QUESTION: I have a 4 month puppy I see her humping my dog and a lot of dogs where trying to get on her. Is it possible that she is in heat? I don't belive that she can be I think shes to small... if she did mate and have puppies would she get sick? so I can separate my dogs. Thanks

ANSWER: This is dominant behaviour.  A dog couldnt possibly be on heat at this age. If you dont stop it now it will cause a lot of trouble when she is older. Get her spayed, and til then every time she does it, put her in a room by herself. Like a kinda time out.

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QUESTION: I called petsmart and they said that dogs can get in heat that young is that wrong? I know you said no but I am stressed out

Answer
Petsmart are also the ones who sell female rats that are pregnant and most of their animals are ill, or genetically messed up.

Get her dressed, Dogs should be dressed anyway to avoid pups and tumours etc.

First heat can vary greatly dog to dog. The youngest is about six months of age. First heat can start as late as 12 or even 14 months of age or later in rare cases. Again, it can vary dog to dog. Spaying before six months is recommended before a female begins to enter sexual maturity. Some vets will spay younger and spaying of puppies as young as eight weeks old who are up for adoption in shelters is becoming more popular. Juvenile spaying will completely eliminate the risk of your pup being one of the odd dogs to come into heat younger than average or you missing the onset of a cycle.