i rescued a great dane aprox 3.5 years old left to starve he weighs 93 pounds should weigh aprox 220?

You've gotten him checked out by a vet right?? the vet would have the best suggestions for that.
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raw meat (breast of lamb is good) with plenty of green tripe. Goats milk and pigs ears/tripe sticks to chew on.
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A vet should have told you that, but if they did not I would say that wet food given in little amounts as not to hurt his mouth. Maybe spoon feed him and put it towards the back of the mouth so he can just swallow it. God bless you for saving this wonderful animal and good luck to you both
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Ask your vet.
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raw food! it is natural and will help him out! throw in some canned dog food if you have to!

thanks for saving this poor "litte" guy ahah

I love danes!
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I'd speak with a vet AND a dane rescue rep. From the vet, you want nutritional advice. Most vets do not recommend the greatest quality food, so you want to know what to look for, not brands.
The rescue rep has probably seen this before and can give you more specific advice for danes.

You don't want to overload his system, and you CERTAINLY don't want to promote bloat.

http://gdca.org/
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feed him puppy food, puppy food has a lot of fat in it because puppies need extra energy so there bones can develop right. I suggest feeding him Buffalo blue dog food.
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i am a veterinary student at purdue university
http://www.bluebuff.com/products/dogs/lp-large-puppy-chick.shtml

Male Danes typically weigh 130-200lbs. (A Dane over 200lbs is very rare indeed and almost always means it's obese.)

Feed a good quality food with a highly-digestible protein, and reasonable amount of fat. Check labels and ask your veterinarian about the analysis of different foods, to find one with a fair amount of calories.

My 10-year-old female Dane was just 69lbs when we adopted her at 8-12 months of age. Since she was young, we fed a large breed puppy food (for the extra calories), and were able to put on about 5lbs per week for the first 7 weeks. She is usually around 104lbs, now. She's very fit, active, if not a bit on the slim side for a female Dane, at 32" at the shoulder (an average height for females). A friend of hers is the same size, age, and reproductive status, and she weighs over 150lbs. So there can be a lot of variation in weight.

Be sure to exercise him, though. Danes tend to be very sensitive, and restricting exercise in the hopes of reducing calorie burn will likely have the oppostive effect. The dog is more likely to become depressed and bored, and eat less. Happy, active dogs tend to eat more.

Good luck!
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Dog trainer for 30 years. Lifelong Great Dane owner/fancier/rescuer.

No Dane should weigh 220#..There are very, very few that do and most of those are overweight.
The average weight for an adult male Dane is 165 - 170 # with some weighing up to 190#.
The best thing you can feed you Dane is a good quality food such as Canidae ALS, Canidae Chicken & Rice, Wellness Super5 Mix chicken, Chicken Soup for the Dog Lover's Soul Regular or Large Breed Adult, Innova, Innova EVO, Taste of the Wild, Wellness CORE, California Natural, Merrick, just to name a few or a well balanced raw or home cooked diet. He should put on weight slowly and steadily. Depending on his height and his bone structure he may not be as underweight as you think.
The typical Dane :18 months - 2yrs - Adult 100 - 190 lbs Height 28"-38"
Typical Dane Adult Dogs 140 - 170 lbs. Height 33"-36"
Typical Dane Adult Bitches 110 - 140 lbs. Height 30"-33

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Dane owner for over 25 years