dog aggressive

Male dogs are more aggressive toward other dogs when they are around a dog in heat?
We have three dogs. Two girls and a boy. The female in the heat and the man has been linked with her several times in recent days. Now it is very aggressive toward the female in heat that was not well before that with reproduction. Even had a litter with her before. If she goes near him or female in heat who is interfering. Im just wondering if other breeders have come through this and if your dog has more that behavior when the woman did with her heat cycle. Thanks in advance.
I've never had the problem of a male to be aggressive to other women, besides the season.I m 'surprise because the female usually get snotty with the other woman or man to another male.I suggest keeping them apart until one is out of season.They should return to normal after wards.If not need to rethink the temperament of the man.
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