I'm with those who suggested to take her to a vet to rule out heartworms or any other parasites or conditions. Its better to be on the safe side
I never really understood the importance of good nutrition for dogs until we almost lost one of ours. I definitely never want to repeat that experience. Basically, she developed bladder stones probably triggered by Beneful & then the vets put her on a food which was worst than Beneful. Which I didn't even think was possible. Anways, after switching her to Orijen grain free dog food within 2 weeks we saw a huge improvement. She got her frisky back, something that we thought we would never see again. On the veterinary diet she was laying around like a mop and had less energy than her mother (who is 6 years older!).
A lot of diseases in dogs are actually preventable by diet alone. The commercial pet food industry has brainwashed everyone. Dogs are carnivores, so why are the majority of their diets coming from corn?! The sticker shock of some foods might come to a shock at first but in the long run they will be saving you from vet bills. Another, thing a lot vets are very clueless about nutrition!
I have 2 Havanese & 2 Papillons, all that have some degree of finicky eating.
Havanese are quite reknowned for their finickiness! I've found that they very seldomly refuse Tripe (Solid Gold) when its mixed in their dry food. Occasionally, I'll mix in some Old Mother Hubbard brand of canned food for variety. Since, you only have one dog -- correct me if I'm wrong. You could ration off a can of Tripe & another canned food together for the week so the rest doesn't go to waste.
My Havanese have been bladder stone free for nearly a year! Not even a crystal which was always reoccuring with the veterinary prescribed food. They are on Orijen. Which was recently rated number one pet food for 2009-2010.
Orijen
Another thing about grain free & holistic brand of dog foods is that with the more protein in the formulas you'll be able to feed less than if you were to feed a brand full of fillers (i.e. pretty much EVERY commercial brand).
My Papillons I rotate between Solid Gold Wee Bits, Wellness Super5Mix Small Breed Adult, Innova Small Bites.
Here is one of the best links I've found that supports grain free feeding:
Grain-free cat food,urinary health, struvite crystals, kidney stones, bladder infections, orijen, health meter detection cat litter, raw instinct cat food,
Very informative site! Make sure the brand you pick stacks up.
Dog Food Analysis - Reviews of kibble
I find that Petco has the most selection of holistic brand but their prices are outrageous. You might check & see if you have a Pet Supplies Plus in your area as they always have much better prices on their holistic brands & they often have samples of the foods too.
Welcome to PET SUPPLIES "PLUS"
I find that the people in dog food boutiques are usually pretty knowledgeable about dog nutrition.