I currently have 3 dogs. Old (13) mix breed about 50 lbs, used to be much heavier, Middle (6) mix breed about 70 lb, and Young (2) Plot hound 45? lbs. All fixed females. Youngest has been with me for about 9 months.
All stay outside. I have always put out ample food for them to share, usually enough to last 3 days at a time, in two separate large pots. They eat from either one, usually one pot gets empty when other is still 2/3 full. Never had any issues, although any one of them might growl if another comes near while eating. Pots are about 5 feet away from each other, and no issues with two eating simultaneously.
I try to re-fill pots before they get empty, but sometimes they get empty anyhow. In the last couple months, the young dog has gotten very defensive of the food, but only towards the old dog. I've only noticed this happen when I am refilling the food pots. Old dog is getting sort of feeble, and the young dog attacks the old one when she comes anywhere near while post are being filled. I mean VISCOUSLY! Not play fighting. I've had to beat her with a shovel to get her to back off. This has happened when other people were filling the bowl too. I have never witnessed of heard any such aggression, except when I the food was actually being filled.
This hadn't happened for a month or so until yesterday. Young got old down and was going for her throat. Then, Middle joined in. First time I have seen this. I could not do much because I have a broken leg and could not get to them. I yelled a bunch and finally managed to pick up a metal trash can an throw it at them, which made them back off. A few minutes later, the young one walked over to the old one and started "kissing" her and licking the blood off her face. Almost like she was apologizing.
Old dog is part blind, part deaf, very slow, but happy and manages to get around. Tries to fight back. Used to be top dog. Keeps to herself and sleeps mostly now. Not interested in playing with other dogs. The other two are constantly chasing each other and play-fighting.
Not sure what to do. Don't want to come home and find old dog torn to shreds.
I do think I will try to separate them while filling bowls from now on. I have a separate gated side yard that they love to go into.
I should add that the old dog has lost a lot of weight in the last year. I think her teeth hurt, as she doesn't devour rawhides instantly like she used to. Not so interested in eating the dry food (even when the other dogs are not there). I have been feeding her special soft (canned and leftovers) - separately inside the garage for a month, and she has gained some weight.
Not sure there are any easy answers here. Sort of hoping the old one drops dead soon. I'd hate to put her down while she still seems happy and can walk.