Breeds Known for Same Sex Aggression

GSDs without a doubt

Dobermans

Most Terrier breeds

English Springer Spaniels

Rottweilers

Jack Russell.  I've seen people successfully keep same sex jacks but I've also heard many people who have same sex aggression problems. My vet has jacks and she had to rehome two females who were intent on killing each other. They may be small but they have enormously powerful jaws and are very strong for their size.  Much damage can be done in a fight.  I was never tempted to get a second JRT, but it would have been opposite sex if I had.

ETA that she did consult a Phd behaviorist and tried meds but for her, the solution was to rehome those dogs, separately of course. 

 Female Border Collies also tend to have issues from my experiences.

 Not adding to the list, but I'm just curious as to what causes same sex aggression in dogs? Anyone know?

The tendency to eliminate reproductive competition is common in the animal world.

Add American Bulldogs to the list

punkchica321

 Not adding to the list, but I'm just curious as to what causes same sex aggression in dogs? Anyone know?

What Jackie said :  and yeah i've seen it in shepherds, collies, terriers..

but the bullies tend to uh.. kill..... the competition. not just dominate it or chase it off.....

 Good point! I never even thought about that.

JackieG

The tendency to eliminate reproductive competition is common in the animal world.

 I think it does some down to having a lower threshold for tolerating sharing resources with same sex dogs which includes reproductive rescoures, as well as territory, food and the owner. FWIW Same sex aggression between bitches is rarely ever solved by spaying.

AgileGSD

JackieG

The tendency to eliminate reproductive competition is common in the animal world.

 I think it does some down to having a lower threshold for tolerating sharing resources with same sex dogs which includes reproductive rescoures, as well as territory, food and the owner. FWIW Same sex aggression between bitches is rarely ever solved by spaying.

That's very true, spaying has been shown to have little effect - but neutering does seem to have an effect on the males.  So, that should be considered if you have same sex aggression between males.

spiritdogs

Just a few breeds that seem prone to aggression toward same gender dogs:

Alaskan Malamute

Kerry Blue Terrier

Boxer

American Pit Bull Terrier

Jack Russell Terrier

 

Are these breeds equally known for same sex aggression in both males and females?

I have a rather *bitchy* female who has experienced high levels of same-sex DA. She can live with a zillion males, and be totally content, but even living with one female can, and has, been difficult for her. Having lived with upwards of 12 dogs of the same breed, I can say with some good faith that same-sex aggression does occur with some frequency, in both males and females. Although I can say that the motives for the same-sex aggression were often quite different between males and females exhibiting the aggression. Males tended to be solely about either breeding rights or defensiveness, while female reasons varied widely.

Both of my females are spayed, and the DA actually increased slightly after the spay (which also has been shown to occur in females - an increase in same-sex aggression). She is a terrier, and pretty much all terrier-like terriers (I say that because there are some breeds named as terriers that really aren't terriers at all!) have higher-than normal levels of DA.

Another link I see in same-sex aggression animals is the comparison between dogs that have been either bred to work as a group, or to work independently. It seems to me that the breeds who have been selected to work independently are also those breeds who often have a higher-than-normal level of same-sex aggression. Breeds selected to work together in pairs, small groups, or large groups like hunting hounds, tend to have a lot smaller dog aggression involved. So really the herding dogs, working dogs, terriers, often tend to be the ones with higher levels of aggression, and the toy dogs and the hounds have lower levels of same-sex aggression (as generalizations, obviously there are caveats).

denise m

 

spiritdogs

Just a few breeds that seem prone to aggression toward same gender dogs:

Alaskan Malamute

Kerry Blue Terrier

Boxer

American Pit Bull Terrier

Jack Russell Terrier

 

Are these breeds equally known for same sex aggression in both males and females?

The way I've always heard it (and have experienced it on my end), is that the males tend to "bicker" more often with posturing, growling, and circling and standing on hind feet, and actually injuring less, but it's the female fights that can be the most damaging. More injuries seem to come from full-on female/female fights than male/male fights. Once again that's a generalization and you can have a very intentfully damaging male, and you can also have a very ritualistic, non-injuring female.

 Many terriers are not very tolerant of same sex dogs.  But then, many terriers have a degree of DA. 

 My sister has Wire Fox Terriers and was advised widely by folks in the breed to get a female when she already had a male and was looking for a second dog.  The breeder she bought a pup from had, in the past, had dogs returned for this reason.... (same sex aggro).  In her experience (very generally speaking) the males were worse in that there were more incidences of aggro, but the females were worse in terms of how bad the fights got.  Some of the males she had dealt with were extremely intolerant of other male dogs (not just the ones they lived with) and could do some serious damage if not managed properly.