sorry for the long post, i am going to try to include as much information as possible in the first post. so here we go.
i adopted my dog (Raj) from a shelter just over 2 years ago. he was a 4-5 month old pup, about 30 lbs. i have no history before that, he came in with 3 or 4 other dogs. he is at 2y4m old, about 70-75 lbs. no idea on breed, looks like a lab/pit or lab/rot mix. lab body but a bit of a box shaped face. he has always been a bit timid to new people, especially men. but loves kids, babies, plays with them like they are another dog, brings them toys to try and play tug o war etc.
way home from shelter i went straight to my parents house, to meet their 4 year old yellow lab, Zorro. they played for a good 3 or 4 hours perfectly. Zorro is a very 'beta' dog, always submits, never starts anything, gets along with every dog he has ever met, etc. probably the most well trained/behaved dog i have ever seen. (also the only dog my sister english bulldog with get along with(a very sad rescue/former fighting dog story), but he pretty much tries to rip the throat out of any dog he meets that is bigger than him, but for some reason they get along like best friends..
within a week he met my brothers two 80lb dogs (lab/collie and a leonberger mix) got along with them with no issues.
every sunday all 4 of them would play for at least 4-5 hours when we all went over there for dinner.
a year and a half and no issues whatsoever. they all got along, ate together fine, played, etc.
he met my sister's shepherd/basset hound (basically a shepherd with legs that are 6" long) at least a dozen times with that year and a half. her dog is VERY alpha, and has some food agression, but we have known that and just feed him in a different room, no issues while playing, giving treats, etc(he was a stray that spent over a year at a shelter). but we have had all 5 of them, as well as a shepherd and a mini pincher, all in the same yard for 6 hours + and they all got along. there was also about 40 people, and there was always food present.
and here is where it all started going downhill.
about 4-6 months ago, my parents had: their yellow lab, my brothers dogs, and my dog for a weekend, and while giving treats, my dog snapped and 'attacked' one of my brothers dogs once. it was all barking, just sounded really agressive/threatening, but no bites or anything.
about 2 months later, my brother watched my dog for a day. no problems between the 3 all day. when i went to pick him up, he was sitting right in front of me, and one of my brothers dogs approached me, in a friendly way, and my dog did the same thing. it sounded like they were fighting to the death for about 5 seconds, but once again, just barking at each others faces, no biting. after i put him on leash, he did it one more time.
a couple more months of playing every sunday, no issues.
the breaking point was last friday. my parents were watching my dog from thursday thru sunday afternoon, my dad was sitting at the table, eating, both dogs sitting right next to each other, just staring at the food, obviously. they do this every time we have ever eaten in front of them. they dont beg, and keep a good 2-3 foot distance from the table. they were not offered food, nor was it anywhere near them, but over a plate, on the table. out of nowhere, my dog turned and bit their dogs ear, which required being put under, and multiple stiches, about a 2 inch cut on his ear.
immediately after, my dog just started licking his wound and just acting like he was his best friend(which they really are, they spend a lot of time together). they had to take him to the emergency vet and all, but when they gt back all he wanted to do was play, which zorro obviously could not do. for the remainder of the weekend no issues, they got along fine, tried to play, shared toys, etc.
this can not happen again, and i do not understand why it is happening. absolutely nothing has changed. same schedule, same diet, food, excersize, ect.
i have contaced some specialists, and they sounded optomistic that they could train this out of him, but at $100/hour for training, and it being very hard to replicate the behavior, i i figured i would make a post in case there is something i am just missing. but at this point i think it may be my only option.