Your pooch may prefer the taste of certain foods over others, something that you may have noticed when offering healthy treats or switching brands of kibble. At the same time, if you live in a multi-dog home, you may notice that one pooch prefers certain things while the other turns her nose up at them.
Wild vs. Canine
In the wild, wolves don't tend to be picky about what they eat. They hunt, eat their prey and survive based on what and when they can eat. Over thousands of years of domestication, however, many pet dogs have developed taste preferences. While some pet dogs still "wolf down" their meals quickly like their ancestors, many dogs will eat at leisure and be much more picky about what's in their bowls because they know their meals are steady and they won't go hungry.
Making Dog Food Tasty
Dog food manufacturers have long tried to make their foods palatable to dogs by adding flavor enhancers. Many of these enhancers are proteins crushed into a powder or formed into small pieces of kibble. Some foods even add ingredients that are similar to junk foods for humans. This is why some dogs will prefer a lower-quality kibble over a high-quality kibble, just as a human might prefer a coated, flavored tortilla chip over a natural corn tortilla chip. A dog's sense of smell may also contribute at first, with dogs preferring something that smells like meat over a bland, odorless diet. At first, dogs will go for the tasty-smelling dish, but after time they will have no preference unless there is a significant taste difference as well.
As they've evolved and been bred, the domesticated dog's diet more closely mimics that of their human counterparts. In addition to the change in diet from raw, fresh prey to an enormous variety, dogs will take cues from humans over what to eat. A study published in "Public Library of Science ONE" states that dogs in a trial would first choose an option of a larger portion over a smaller one; that is, until, a human showed more interest in the smaller portion. After seeing a cue from a human being who preferred a smaller portion, most dogs would choose the smaller over the larger.
Another interesting aspect of a pet's food preferences is the novelty effect. A dog fed a diet for long periods of time, whether he thoroughly enjoys it or not, will often choose a new, different tasting food or kibble over his regular diet. Conversely, some dogs will refuse a seemingly palatable food that they have never experienced before.
The domesticated dog is such a diverse species that it's nearly impossible to say every dog will like one thing. Humans have interfered with the dog's genes through selective breeding for certain traits, and science is unsure about the effects in regards to taste preferences. In general, however, dog taste buds react greatly to sweet and umami flavors in foods, much like human taste buds. The most common taste buds in a dog respond primarily to "sweetish" tastes, which could account for the preference of raw meat and carrion. A dog's sense of smell is also prevalent in the preference of certain foods over others; anosmic dogs don't show much preference between different meats or foods.