A bit of a long story but hoping for some advice! We have 2 dogs who have lived happily together for 2 years but suddenly showing aggression to one another. Regis is 9 years old and we rescued him 7 years ago. He is a cropped ears bully-type breed and was rescued from a hoarder, and had many issues (separation anxiety, aggression towards strangers and other dogs). Nobody was keen on him so we ended up keeping him (me and other half are vets so end up seeing these sorts of cases!). His issues improved but never fully resolved. His aggression with strangers is resolved easily by imtroducing them properly, then he loves having them over and playing/interacting with them. His aggression with other dogs is a bit harder. Most male dogs he will show signs of issues from spotting them down the road, hackles rising/lip-licking/stiff legs. Others (female generally) he is very excited to meet, showing playful and submissive signs however he can turn at the blink of an eye. Generally we found that the risk wasn't one we were willing to take so he is always on-lead and we don't go out of our way to let him meet dogs.
However then 2.5 years ago we were landed with another female rescue, approximately 3 years old. Somehow they got on really well, he accepted her completely within a few weeks and we were comfortable letting them live side by side (on a side note she is quite reactive to other dogs so they definitely made each others aggression out of the house worse!). For 2.5 years no issues at all, barely a spat over a bone here and there but very rarely and always more of a snarl than anything else.
Suddenly a week ago Regis (older dog) seems to have turned against Nala (younger one). No obvious triggers, no fight over food, no strangers or even guests around, no fireworks, nothing unusual on their walk. He just suddenly started eye-balling her around the house. It has deteriorated to the point where he can't be in same room as her without looking on edge and stiff walking around. Has gone for her a couple of times (no wounds). Any help? We ran routine blood work for him and nothing unusual, we have a pet diffuser in the house, trialling a week of pain relief in case he is sore somewhere. We are giving him the most attention to try and ease his insecurity and making sure we don't shout or punish him after he goes for her
However then 2.5 years ago we were landed with another female rescue, approximately 3 years old. Somehow they got on really well, he accepted her completely within a few weeks and we were comfortable letting them live side by side (on a side note she is quite reactive to other dogs so they definitely made each others aggression out of the house worse!). For 2.5 years no issues at all, barely a spat over a bone here and there but very rarely and always more of a snarl than anything else.
Suddenly a week ago Regis (older dog) seems to have turned against Nala (younger one). No obvious triggers, no fight over food, no strangers or even guests around, no fireworks, nothing unusual on their walk. He just suddenly started eye-balling her around the house. It has deteriorated to the point where he can't be in same room as her without looking on edge and stiff walking around. Has gone for her a couple of times (no wounds). Any help? We ran routine blood work for him and nothing unusual, we have a pet diffuser in the house, trialling a week of pain relief in case he is sore somewhere. We are giving him the most attention to try and ease his insecurity and making sure we don't shout or punish him after he goes for her
