I am having a VERY hard problem right now. For the last month or so, we have been having problems at our house. Now Koda, (golden retriever/chow) has always been food aggressive and crate aggressive with other dogs. Never has been an issue because I keep their crates seperated and they get fed at night seperate from each other. Recently, the dogs will find old treats in the yard or grass or really anything that they can pick up(even rocks) and Koda then will get VERY aggressive with Chi-Ching. Koda will attack him, He chews on the back of his neck. In the past month or so, he has bitten him multiple times and made him bleed once. Now it is happening over nothing at all. For the most part they get along great, they can go a week and be perfect playing together and then Koda will just freak out on him. Koda has not really been the same since Kaia was put to sleep(another golden/chow we had). We thought that since we got the puppy fixed so early their would be no issues and as Chi-Ching gets older, the fighting is happening more and more. Chingers doesn't fight back at all...right now. But I am terrified what will happen once that stubborn puppy decides that he has had enough. Right now, I am more afriad for Chingers, he is alot smaller then Koda and Koda is not just giving a warning snap, he will bite down on Chingers neck and "chew". It gets the puppy screaming. then he will let go when we go out there. Koda has always been around either little dogs(pomeranians and a doxie) or female dogs. Any of the other dogs we have had in foster care were never here more then a few weeks. Chingers is the first "big" male dog to be here for longer then just a few weeks. I am afraid that this is male/male aggression but I do not know what to do. Can two males live together peacefully? We do make Koda Alpha by giving him everything first from petting and treats to bedtime and dinner. But Chingers does not seem to be trying for a higher rank, he just wants to play. Koda has changed so much. It is hard because I can't trust him with Chingers alone, I never know why or what may make him freak out. I am afraid that this is only going to get worse as it seems to be almost doubling weekly. Both dogs get quite a bit of one on one attention seperate from the other. I had been told that I should bring Koda with me when I take Chingers to training but I think that that may backfire as Koda gets VERY jealous when I work with the puppy on training and he has to stay back. He will start whining(he is not normally a whiner at all) and when he gets to me, he will jump up and push the puppy out of the way. Sometimes giving a small growl. So I know that I am a reason for part of his aggression but at home, he does it when I am not even near him, usually it is when the two of them are outside. I do not know what to do. If anyone has any ideas, please let me know.
Yikes Katz, I have not dealt with this issue. It seems you are doing all the right things. I wonder if time outs would work with dogs. Maybe Kitty will know what to do.
I've had that problem. When I got my mothers dog loki we would watch my grandparents dog alex and loki didn't like alex what I did which I don;t know if its the best idea but it worked and after about a week or two they left each other alone.
Every time loki would go after alex I would take what ever it is from loki and give it to alex and then put loki in another room for a few minutes. Eventually I think he figured out that this would keep happening everytime he messed with alex.
I'm sorry to hear that some problems have arisen. I have never had two dogs of the same sex at the same time but I have heard that having 2 males is better than having 2 females so I think you have that going in your favor.
Do you still doing regular training sessions with Koda? If you aren't I would suggest give that a try - it will be more extensive one-on-one with you & Koda. If Koda has a reliable sit/stay or down/stay I would start incorporating that with him when you are having short training sessions with Chingers. Koda's session 1st, followed by Chingers.
As you said you are already doing I wouldn't have the two of them together unsupervised and that goes with going outside as well.
Although my 2 generally get along very well even stealing toys & treats from each other (it is a game they play & watching their minds working on how to win the "prize" is hysterical) they will on rare occasion get into a real spat. They have learned if I yell "ENOUGH" it is time to immediately quit. At times though when they are playing they do sound ferocious but it is definitely play with no one getting hurt. In the beginning it was hard for me to tell if it was play or fight. In fact Farley is extremely vocal when playing and he has a very low timbre which enhances the "mean" sound.
I did have both of mine at training together. Chloe's class was 1st and Farley's was 2nd. During Chloe's class we would all be subjected to Farley's whining & moaning away in the crate (I had to crate him for quite few weeks because he wouldn't stay and would join us during our routines). When it was Farley's turn, Chloe would just lay down & quietly watch. Now 95% of the time Farley will stay w/o being crated. He loves to work and it is hard for him to sit out but now all we have to put up with is the occasional sad moan & groan. This session they now go to class on separate nights but since I do periodically teach classes one or the other will come with me as my "demo dog" and for a good part of the class be on a down/stay. But both are thrilled if they get to participate.
If it does continue though I do think your best course of action would be to consult with a qualified behaviorist as versus a trainer, who could help you find a workable solution. I'll keep my fingers crossed & ask around some trainers I know to see if they have any suggestions.
I have two females, one of whom is a recovering resource guarder. When I first found McKeever, she would guard a one-inch piece of string and was very food aggressive. She has gotten much better and can now play nicely with almost any kind of ball and tug toys, and she no longer gets nasty just because there's food in the room.
Here are some things that I did that helped: first, they get zero unsupervised time together for now. Do not put them in the yard together while you're in the house. Get a bunch of baby gates (if you don't already have them), and use them to keep the dogs in the same room you're in. If you're going to leave the room, even for just a second, at least one of the dogs must come with you or go into a crate.
Food
Start teaching Koda that the presence of food is his cue to look at you. Stop feeding him in the crate. Instead, put Chingers in the crate while Koda eats. Go back to hand feeding. Put a couple of pieces of food in your hand, and hold your hand out to the side. Koda will probably target the food. Just wait. As soon as he looks at you, click and release the food. (I've found that a clicker is much faster than a verbal reinforcer, so it works better when you're looking for just a look or slight head turn from the dog. You can get a clicker for a dollar at a pet store.) Feed Koda his entire meal this way. Meals will take a long time, but the payoff is worth the effort. After a while, he'll briefly glance at the food and then quickly look at you. Once he's pretty good at that, start increasing the amount of time he needs to maintain eye contact before you release the food. If he breaks eye contact, say "oops" and turn away from him with the food still in your hand. After a minute try the exercise again.
Meanwhile, Chingers should be learning the down-stay on his own. This exercise will come in handy later. Once Chingers can do a pretty good down-stay, have both dogs do down-stays side by side (without any food present).
After Koda can maintain eye contact for a long time reliably, start adding a sit with eye contact, then a down with eye contact, then a sit-stay, then a down-stay. Eventually, you should be able to move around the room, and he will continue to look at you instead of the food. After you get to that level, start putting the food where he can't reach it, walk away from it, and then have him come to you (away from the food) and make eye contact. When he does, click and get him some food from the bowl.
Does Koda know "leave it?" If not, teach him, and start with objects that are only mildly interesting. Work up to high-value objects.
Eventually, you should get to the point in which if you put kibble on the floor, Koda will look at you instead of rushing for the kibble. Reward him with treats much better than kibble, something like chicken.
Once Koda has the eye contact thing down, start bringing Chingers into the room for Koda's meals. Put Chingers in a down-stay at one end of the room, and go back to basics with short eye-contact from Koda at the other end of the room. Paying attention to you leads to food; paying attention to whatever Chingers is doing does not lead to food. As Koda's eye contact with you improves, move Chingers closer and closer to where you are. Eventually, you should be able to let Chingers be free in the room while you hand feed Koda.
Also, when they get good at doing down-stays together, start putting objects they want some distance in front of them. Eventually, work up to leaving food in front of them. When you leave food in front of them, Koda should make eye-contact with you through the down-stay.
Your goal is to work up to a point where if Koda finds an old treat or a dropped piece of food, he comes to you and makes eye contact instead of taking whatever he found or trying to guard from Chingers. He will perform this action if he learns that doing so will often get him more or better treats. If you see Koda start to make mistakes at any point in the process, back up a step.
Now if I drop a piece of food, McKeever rushes to make eye contact instead of getting nasty with Argus about the food. She knows that my dropping something often leads to her getting cheese if she comes to me, sits, and makes eye contact.
I'll write an essay on toys and other issues later.
Some dogs of the same sex will never be safe around each other, but some who have issues can learn to get along if you work very hard to manage the situation.
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"Thought is an invisible and subtle power that mocks all the efforts of tyranny." Alexis de Tocqueville
This session they now go to class on separate nights but since I do periodically teach classes one or the other will come with me as my "demo dog" and for a good part of the class be on a down/stay. But both are thrilled if they get to participate. 
"Thought is an invisible and subtle power that mocks all the efforts of tyranny." Alexis de Tocqueville
