Hi Katie,
Bless you for taking on this big boy. He’s lucky to have you.
I would think it’s likely that the chewing and biting could be food intolerance / allergy issues as much as it could be compulsive behaviors. Would you be in a position to try to distract him every time you catch him chewing? A quick walk, a quick game of fetch, a doggie massage? Also, maybe give him something healthy to chew on that is tastier than his nails or fur. That’ll give him some extra calories also. Try bully sticks or raw, meaty bones like a turkey neck for snacks and chewing satisfaction. Samoan81’s suggestion for satin balls is a also a great idea.
I think I’d get him off of the grains though and would definitely increase his protein. His body needs more protein to repair and rebuild. I wouldn’t use anything less than 30% protein. He’s an adult now, so you don’t have to be as concerned with Calcium levels ~ which are what you limit with a large / giant breed puppy ~ not protein. While she mostly suggests foods with grains, the Great Dane Lady has a list of foods she recommends along with some great advice. Have you visited her site: http://www.greatdanelady.com/. Also, here’s a link that’ll take you right to the page of foods she recommends: http://www.greatdanelady.com/articles/criteria_list_of_better_foods.htm.
Also, one food I’ll suggest you try adding to his diet is Abady granular. It’s usually very well tolerated and is very calorie dense, about 800 kcals per cup. Their website is very strange, but I would suggest calling them and telling them what’s going on and get their recommendations. They’re extremely helpful over the phone. Here’s their website: http://www.abadyfeeds.com/ and here’s their phone number: Tele: (845)473-1900 * Toll Free: (877)-99ABADY .
Have you tried giving him some pureed pumpkin for the loose stools? That usually helps a lot.
Peace & Blessings,
Betsy
