The most interesting problems of food behavior from a clinical point of view are, in the dog, the obesity and the coprophagy, and in the cat, the anorexia, the obesity and the pike.

The obesity can be defined as an increase of the corporal weight above 15% of the ideal weight that corresponds to the dog for breed, sex and age.

The obesity of the dog has followed during the last years an parallel evolution that affects the persons. Every time there is a major the number of dogs affected by the problem, which in some countries might overcome 25% of the canine population.

The reason of the obesity is a superior caloric contribution to the real needs of the dog. This imbalance is in the habit of being the result, first, of an excessive consumption of food, and secondly, of a limited physical activity. Some breeds show a major tendency to endure obesity, as the Beagle, the Cocker Spaniel or the Labrador Retriever. The dogs and especially the gelded bitches show also a major predisposition to obesity.

From a veterinary point of view, the obesity is considered to be a real disease. The obese animals show a life expectancy lower than those who does not endure it. Besides, the prevalence of many diseases, as the diabetes or the arthrosis, is superior in dogs with obesity. In this respect it is essential to convince the dog owners that an overweight is considered today as a form of bad nutrition, and not the indicative of health and well-being.

The programs of weight reduction are usually are based on the utilization of low calories diets, with the prohibition of giving any other food to the dog. Nevertheless, many owners are unable to follow strictly this recommendation. In opinion of some specialists, it has a relation with the existing affective relationship link that is established between the owner and his dog and the fact of providing prizes in shape of food.

The origin, consequences and measurements of treatment of the obesity of the cat share the same general principles described for the dog.

The coprophagy can imply the consumption of faeces of the own dog, of other dogs, of other animals and even human.

From an ethological point of view, the coprophagy is a more a troublesome conduct for the owners, than harmful to the dog. The coprophagy is considered to be totally normal in females in lactation phase.

It is important to discard the existence of digestive problems that favor the appearance of the problem. Once discarded an organic problem, we must do a detailed study of the dog conduct. Some dogs that show coprophagy are in environments with few stimulation, without contact with persons or with other dogs. In fact, the confinement of a puppy during the period of socialization seems to increase the probabilities of which in the future it shows a coprophagy problem.

It does not exist an unique treatment for coprophagy, because every case must be analyzed in individual form. In any case, the increase of exercise and the degree of stimulation of the dog, to provide eatable toys and to place repellent substances in the faeces, are mechanisms of control that can be effective in many cases.

Anorexia is a very frequent symptom in the cat, which consequences are very serious, and in some cases even mortal. The etiology of anorexia is diverse, and includes as organic problems as behavioral problems. Once discarded an organic reason, we can value the possibility that the anorexia could be a behavioral problem. The changes in the diet or any environmental element that provokes stress can be responsible for the appearance of this problem.

In the cases of anorexia owed to a stress reaction, the treatment consists in the correction of the environmental reason that causes stress, together with the temporary administration of anxiolytic medication.

In the cat, the most known form about pike is the ingestion of wool or other textile fibers. Cats with this problem chew articles of wool or other fabrics. In many occasions the cat starts showing this conduct towards pieces of wool, and with time it directs also to other materials, as cotton, synthetic fibers and even plastic. The movements showed by the cat resemble those of a kitty while it sucks. In fact, some authors suggest that the problem would be more frequent in kitties weaned prematurely, between 2 and 4 weeks of age.

The appearance of this problem has consequences both for the cat and for its owners. Though with few frequency, some cats can endure an obstruction and need a surgical intervention. For the owners of the cat, the damages caused in the property can be considerable.

The treatment of the problem includes diverse recommendations, among them the punishment of the behavior by means of water spray, the placement of substances to which the cat feels distasteful in the affected places. Some authors suggest an increase of fiber in the diet, which will have to be available in the plate during the whole day.

Finally, it is important to emphasize the relation that can exist between trophic conduct and those suffering of FLUTD's cases that include formation of struvite crystals. Apparently, one of the factors that favor the formation of these crystals is a high pH of the urine. The food administration ad libitum promotes a more fractionally consumption of the diet and reduces the degree of postprandial alkalinization of the urine.