High in fat and cholesterol (both excellent sources of canine energy), eggs are also high in calories that can pile up with too many of these golden globules. Diet is important in coat care, and with care, eggs yolks can be liquid gold for dogs.
If your dog's coat looks dull and dry and you've checked for external parasites and you're not bathing him too much or with the wrong products, try a couple of egg yolks mixed into his food each week. The additional protein, fat and vitamins may be just what he needs. If his coat doesn't look better in a month, the cause is probably not nutritional and you should check with your vet for other problems.
Vitamins A to Z
In addition to the fat and cholesterol (more than is good for some humans), egg yolks are loaded with vitamins and minerals, including biotin. This substance is also known as Vitamin B7 or Vitamin H, and a lack of it in a dog's diet can cause a dry coat, hair loss and skin problems. If your dog is allergic to eggs or just doesn't like them, try giving him carrots -- they also contain significant amounts of biotin and may help, and they have fewer calories.
To Cook or Not to Cook
Cooking an egg makes the white more digestible, but makes little change in the nutritional value of the yolk. Raw yolks are safe for dogs to eat. If your dog won't eat raw egg yolk, try soft-scrambling it.
There's been lot of buzz recently about grocery-store eggs being contaminated with salmonella enteritidis, a nasty little bacterium that can cause food poisoning, and an egg yolk is a great growth medium for salmonella to flourish. However, indications are the number of infected eggs is small and the number of bacteria in any one egg is few. Dogs are far better equipped to handle a few nasties than people are, so if you store your eggs properly and use them promptly, there should be no problem. If your dog is old, sick, pregnant or nursing, cook the egg yolks well before you serve them, just to be on the safe side.
We've been talking here about chicken eggs, because they're what most people think of, but there are other eggs whose yolks contain even more fat, cholesterol and nutrients. These include turkey, duck, goose, quail and even ostrich eggs. If you have access to any of these, feel free to use them. Turkey, goose and duck eggs are larger, so adjust the number of yolks fed per week accordingly. Quail eggs are so tiny that even if you raise quail and have infertile eggs to spare, it would be hard to overfeed your dog on them. An ostrich egg is equal to approximately two dozen chicken eggs, so if you just happen to have one, beat up the yolk and portion it out a tablespoon at a time (1 tablespoon of yolk equals the yolk of one large chicken egg).