There's a few things you can do to help a situation where you're dealing with a dog who has a bad appetite.
One option would be to look into the possibility of appetite stimulant medications that can be prescribed by your veterinarian. They can work wonders for animals who have chronic appetite issues, especially when their overall health is adversely affected.
Another option would be to determine whether the dog is suffering from a stomach or other digestive system issue that's causing pain or discomfort as a result of eating. If every time the dog eats, he's experiencing discomfort or pain, then he's not going to have a very good appetite because he associates eating and food with discomfort and pain.
One common cause of problems is excess stomach acids, which can cause ulcers and irritation to the stomach lining and vomiting (often first thing in the morning, comprised of a yellow liquid). Pepcid is one medication that can work well for controlling these problems. (Let me know if you'd like some additional information about this)
Frequent meals can also help. In the case of an overproduction of stomach fluids, this will make it so that the stomach is more often containing food, which gives the fluids something to act on. The food acts as a sort of "padding" so that the fluids are not irritating an empty stomach.
Some dogs with sensitive stomachs also appreciate three or four smaller meals throughout the day. It's much easier for the system to handle and he won't have to deal with a heavy, full stomach from just one or two meals a day. Hydrating dry food can also be helpful, as the food expands before it enters the stomach. You can let the food sit in hot water for a couple of minutes - let the food swell and absorb the water. If you give dry food, the dog will eat until he's full. Then the dry food expands as it absorbs the fluid, making an already full stomach even fuller, which can cause discomfort and vomiting.
Sensitive stomachs can also benefit from prescription bland foods from your vet. Hill's for example, makes I/D, which is a bland food that's easy to digest.
There's also all sorts of sauces and gravies out there that can be added to foods to make them more palatable. Iams makes a product called "Savory Sauce," which is available in the food aisle of the pet store or supermarket. And you can also try small amounts of gravy, which can help as well.
Another option would be to try a higher quality food. My favorite is Hill's Science Diet. And there's also prescription foods that are high-calorie. This way, while your dog may not be eating all that much, but he'll get more nutrients with what food he actually does eat. So that's another route to go if appetite is an issue.
I would also make sure that your dog is comfortable while eating. Uncomfortable stimuli while eating can result in appetite issues. Some dogs feel uncomfortable eating beside a sliding glass door, for example, as this makes them feel exposed and vulnerable. Eating with other dogs in the same room can also create anxiety, as there's natural competition over food in the dog world. And when we're anxious, our stomach's feel all wrong, and eating isn't top on our list, so this could be a factor as well. I would see to it that he's undisturbed by other animals and people, in a cozy, quiet area. A bathroom may work well, for example, if you're looking for a small, cozy area where he'll be undisturbed for a few minutes.
Another option would be a new diet, like a raw, natural diet. BARF is one natural diet for dogs and many pets with food sensitivities or poor appetites benefit from this.
Here's a site to learn more:
I hope this helps your boy! Don't hesitate to let me know if you have any additional questions!
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