I have been fostering greyhounds for nearly 10 years now and have adopted 9. (Not a bad average, I'd say.) *VBG* I've learned a lot about them and their eating habits along the way.
I have to agree with the second poster on this thread. Raw is better than cooked,(both meat and veggies) but you have to start very slowly with a BARF (Bones and Raw Food) diet. You can't just jump right in or the dog's digestive systems will take a 180 on you. Also not only are onions not good for your dog, (can cause anemia when fed long term) but garlic does the same thing. They are closely related.
Having said that, some racing kennels feed their dogs a mixture of meat and veggies including red onions. They claim it thins their blood. I'm not sure it's really worth the risk.
I have been using Safflower oil on their food, (at the suggestion of my vet) for about 8 years now and I can't extoll it's virtues enough. Shiney bright coats, no more dandruff ot dull dry itchy skin. Wonderful stuff. I use about a TBLSPN once a day on each dogs food. It even makes the white dogs shiney!
I also add the same amount of yogurt each day. It helps with digestion and cuts down on gas. (Don't feed canned food to your GH unless you like sleeping in a seperate part of the house!)
BTW, the canned pumpkin is also good for curbing coprophagia, (stool munching) as is pineapple juice.
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