Dog Biscuits. Can't say enough about Jumbo-sized dog biscuits for easy, cheap, wholesome snacks. They clean teeth.  They are very portable for travel.  They are readily available.  They have very little fat.  And the dogs love them.  Especially if you use the biscuits as training opportunities when bringing dogs in and out of crates and kennels an door ways.

Yogurt. We use a lot of yogurt, plain, active-cultures yogurt.  It regulates the digestive system.  It aids in the growth of skin, teeth, nails, and coat.  It's cheap.  And the dogs love it.  We generally give a heaping teaspoon EVERY morning with their first of two meals/day -- UNDER the kibble.

Raw, meaty bones & knuckles.  Usually beef thigh bones or chicken carcasses available from a butcher or processing plant.  Not cooked.  Not smoked.  Just the raw bone with marrow inside and meat clinging to the outside.  About once a week.

Raw, frozen, chicken drumsticks. Don't have a cow.  BARFers have been doing it for years.  So have dogs, given their reputation for chicken killing -- they just get them fresh.  Hard freezing kills many harmful bacteria.  And the dogs will love you for it.  Raw bones are NOT brittle.  Cooking makes bones brittle -- and dangerous.  Dark meat is "richer" and can cause tummy upsets if they are not used to it.  But mine all enjoy their drummies every week.  Some lick them like lollipops.  Some gnaw on them like sticks.  They ALL finish every morsel.

Fried Eggs.  We have egg night every week.  Fried eggs over easy.  Teflon skillet.  Two-four eggs each.  Cooked whites (where salmonella lives) and runny yokes (where nutrients live) By the time I am on the third set, the first is cool enough to serve.  I generally withhold kibble on egg night.

Cottage Cheese. About weekly we use a heaping teaspoon of cottage cheese instead of yogurt.  Under the kibble.

Canned Dog Food. About weekly we'll add a heaping tablespoon of canned dog food.  We prefer IAMS (no corn), or any of the fake-meat-chunk types that spoon easily.  The nutrition in this is negligible, the TASTE value is immense.  Especially if you warm it in the microwave ahead of time -- it's irresistible to dogs.

Sweet Potato. Fresh, 1"-thick, sliced sweet potato is microwaved until cooked.  Then mashed into the bottom of the bowl and the normal kibble ration poured on top.  Sweet potato is a natural stool FIRMER and some will say de-wormer.  Try it and see.  No butter.  No cinnamon.

Green Beans.  High fiber, low calories, no fat.  Warmed they are a great, and cheap addition to a bowl.  Watch salt content in canned veggies.

Veg-Al. Canned veggies can be high in salt, but they are so convenient.  WARMED slightly before kibble is placed on top.  Too many leafy greens can LOOSEN stool, so watch your amounts.  We generally try to add veggies once a week, about 1/4 cup.

Canned fish.  Not tuna.  At least not often.  Check your salt contents and you'll see why.  Mackeral.  Salmon.  Occaisionally sardines.  They LOVE it, and you can take a 15 oz can and divide 10 ways.  They all get the smell and taste without a LOT of extra fat.  (Unless you are LOOKING for extra fat.)

Apples.  In or out of season, my guys adore apples.  Sliced, whole, frozen, fresh, right out of the grocery bag if I don't pay attention when putting things away.

Raw eggs. Again, don't have a cow.  Dogs have been eating raw eggs forever.  My dogs in particular.  No ill effects except being spoiled.  I'll break a raw egg over kibble maybe twice a month.

String cheese. Usually low in fat.  Can be bitten into coins or pulled into strings.

Sliced, pre-prepared Chicken Breast. Many Super Center grocery stores carry this in the deli.

Hot Dog Coins. Get low-fat, turkey dogs.  Slice into thin coins.  Spread on paper towel.  Microwave until they crunch.  Let cool.  Last a long time in the fridge.  Dogs generally love them.

Fake Crab Meat. Some i stringy and some is not.  Experiment with your local brands.  It's white fish.  It's cheap.  Dogs love it.

Carrots. Some dogs love them.  Some hate them.  They are crunchy and most training treats need to be soft so the dog doesn't drop his head, loose eye contact, and wonder away in the middle of training.

Bread.  OK, to be perfectly blunt, peanut butter sandwich crusts.

Roast Beef. A lot of fast food chains will run them on special for 99 cents.  You can get a LOT of warm sliced meat for a buck if you forget your treats on the way to class.  But you might have to share with the instructor.

Natural Balance Dog Food Rolls, Rollover, Red Barn -- sliced into 1" disks and then into 1/4" sticks.

Chondroitin/Glucosamine.  We pay close attention to what C/G is added in kibble, but usually that's a prevention level, not a treatment level of joint care.  Our seniors are generally all on it with good results.

Fish Oil Caplets. Fish oil is a source of fatty acids.  Fatty acids are the building blocks of the body.  Any pregnant bitch, all seniors, and any dog recovering from injury or illness is fish oil.

Pet Tabs Vitamins. On the off chance that one of the seniors is not handling the particular source of vitamins and minerals in any given kibble, we give a pet-tab a day.  Are we falling for the media hype?  Yep.  And if you took a multi vitamin a day, you would understand why we humans do as well.  You DO see a difference.

Alfalfa.  It's new, it must be wrong.  You gotta be a quack to fall for the holistic mumbo-jumbo.  But this is another one that works.  Our seniors all get alfalfa.  We see better coats, better skin, and more energy.  It also seems to improve their immune systems.  Can't site you any studies.  It's just a gut feeling from watching the results.