When your dog is not eating well every day, there is a risk that your dog becomes anorectic. A lack of appetite is what dog breeders are confronted with day in day out.  There are a lot of different reasons for this problem but a stress factor is certainly one of the major reasons in the kennel. Anorexia is defined as the lack or loss of appetite for food. In veterinary medicine, it is one of the most important and most common complaints indicating a myriad of diseases with greatly varying pathogeneses.
It might be more appropriate to talk about hyporexia here. Hyporexia means a reduction in appetite rather than a complete loss. Dogs that are completely unwilling to eat can rarely be forced to eat a sufficient quantity to meet their daily energy intake requirement and need assisted feeding (nutrition provided parenterally or by tube feeding).
After appropriate medical therapy, the most common initial strategy to get a patient to eat is to enhance the palatability of the pet food.
What techniques are currently used and how efficient are they?

1- Increasing moisture

Switching from dry food to canned food or pouched food may prove effective. The reason for this is the higher moisture level, but canned or pouched food also typically contains more fat and protein. Care should be taken that these increased fat and protein levels do not cause any adverse effects. You should also be aware of the fact that the canned or pouched version is not always exactly the same as the dry food. So an alternative to switching to canned or pouched food is to simply soak the dry kibble (2.5 parts of water to 1 part of kibble).

2- Increasing fat

This is mostly done in therapeutic foods to increase the energy density so that less food has to be consumed. Note that increasing the fat content is not without danger, so we do not advise to increase palatability by increasing the fat level of the diet.

3- Increasing protein

Care should be taken when increasing dietary protein in certain disease processes, such as hepatic failure with hepatic encephalopathy and renal failure with acute uremia.

4- Sweet and salty

Adding a sweet flavor by using sugars or syrups as a top dressing may increase the palatability of the food for dogs. Artificial sweeteners should be avoided because they have little to no nutritive value and a common artificial sweetener, xylitol, can cause a hypoglycemic crisis in dogs. Caution should also be exercised when treating diabetic patients.
Salty foods can be effective in getting some dogs to eat but be careful with patients with hypertension, edema, ascites or renal disease. We don’t find this strategy very effective because the preference we saw for some salty foods (potato chips, salted nuts, peanut butter) may in fact be a preference for fat or treats in general that is somewhat independent of the food’s salt level.

5- Freshness, aroma and food temperature

Freshness and warming food (not higher than body temperature to prevent burning the patient’s mouth) can be helpful because of the additional release of aromas. This is of course important in patients with a reduced sense of smell such as older dogs and renal patients. Keeping the food fresh during storage is very important.

6- Rarity

A rare food may be more enticing than a common food, but types of food that are completely novel may not be the best choice.

7- Variety

This may be an effective incentive approach but there are several cautionary points.

8- Polypharmacy avoidance

Common pain medications, antibiotics, antifungals, diuretics, anti-inflammatories, immunosuppressives and chemotherapeutics can reduce appetite. The best approach is to try alternative ways of administration that might mitigate some medications’ adverse effects on appetite.

9- Eliminating physical barriers to eating

Examples of such physical barriers are Elizabethan collars, poor bowl location and dental or oral pain.

10- Appetite stimulating drugs

Diazepam, cyproheptadine and low-dose propofol are not recommended because their effects seem to be unpredictable, intermittent and short-lasting.

After careful consideration of the 10 techniques described above, it is clear that in the past no effective treatment was available.