male not interested in female

Question
Hi I have a male chihuahua who has been a stud MANY times we have a female over her who is in heat and is ready to go she is flagging him and pushing up against him and pocking her little thingy out at him lol but he is not wanting anything to do with her..... is there anyway you could tell me why he is acting like that i mean he is growling at her and all if you could help me it would be deeply appreciated thanks

Answer
Sounds crazy but have you had both of them vet checked? She could have an infection that he is aware of and you are not. Or she could be ready to stand and not yet ovulating. It happens and experienced males often know it and won't breed. He could be not feeling well, sometimes not eating, or not breeding are the first and now and again the ONLY symptoms of a dog that is becoming, or already is, ill
Have them both vetted.
Good luck
Cindi