I have a 14 month old cockapoo who has some anxiety it seems more towards men. She will let out a very low growl. Does not show her teeth and I think it happens more out of fear, than anything else. I've also found that I think it happens more when that person is wearing a hat or glasses, and looks a little different. Once she meets them, she is fine! Very friendly, etc...
She is presently undergoing therapy dog training, and is very friendly towards all! I have been bringing her already to school with me a couple days a week and she's been fabulous. This behavior does not happen with "boys", it just appears to be grown men.
This behavior (low growl) also happens with other dogs when we are out on a walk. Although it is much better, it still can happen occasionally.
Is this an "alpha" type of a problem. Any suggestions would be most helpful. One tiny little growl towards a person on a therapy dog test is an immediate fail, no matter how friendly she is once she meets them. She has not met a person that she does not like yet! I really think she can work through this. She's very intelligent and has so many positive qualities.