The rule with bones for dogs is this. NEVER give a dog chicken or poultry bones of anykind. They can splinter during chewing and choke the dog.
As for meat and pork bones, they are ok as long the pork bones are the nuckle portion and both are cooked. There are numerous "recipes" on the net you can find on how to process bones for dogs.
I guarantee you someone on here will disagree with my comments and tell you they've fed chicken bones etc to their dogs for years with no problem. Some dogs can handle it, however no Vet will ever recommend giving them to a dog.
It's like chocolate. Dogs can be deathly allergic to chocolate. Last May I lost my Brittany/Springer Spaniel baby, Leetah, to liver cancer. She could eat chocolate with no problems. Even at one point getting a hold of a ziplock bag filled with 2 dozen cookies and having an evening snack while we were out. However my next-door neighbor lost her poodle this past Christmas when her dog got into some chocolate she was using to bake with. The dog was dead before they could get it into the car to the vet.
The point of this long post is simple. Why take chances? If you want to give your dogs bones for chewing go to a reputable pet store and purchase good quality bones at the right size for your pet.
There's a reason for the difference in reaction. It takes a lot of milk chocolate, found in chocolate chips, to be harmful, but baker's chocolate is lethal even in very small doses.
We've all heard it, "Don't give your dog chocolate it will kill him". We'll how true is it you're probably wondering. Do I have to rush him to an emergency vet if he ate one of my M&M's?
The truth is chocolate contains theobromine that is toxic to dogs in sufficient quantities. This is a xanthine compound in the same family of caffeine, and theophylline.
Toxic Levels
The good news is that it takes, on average, a fairly large amount of theobromine 100-150 mg/kg to cause a toxic reaction. Although there are variables to consider like the individual sensitivity, animal size and chocolate concentration.
On average,
Milk chocolate contains 44 mg of theobromine per oz.
Semisweet chocolate contains 150mg/oz.
Baker's chocolate 390mg/oz.
Using a dose of 100 mg/kg as the toxic dose it comes out roughly as:
1 ounce per 1 pound of body weight for Milk chocolate
1 ounce per 3 pounds of body weight for Semisweet chocolate
1 ounce per 9 pounds of body weight for Baker's chocolate.
So, for example, 2 oz. of Baker's chocolate can cause great risk to an 15 lb. dog. Yet, 2 oz. of Milk chocolate usually will only cause digestive problems.Source: Dogs and Chocolate Toxicity