Last Friday a US dog lover asked my recommendations on the energy requirements of a rather obese dog. Below you find an excerpt of my response to them.

A six year old chihuahua/dachshund mix had been gaining weight from 7.5 to 10 pounds. Assuming the 7.5 pound is the ideal weight, this dog suffers from 33% overweight… which is just too much! A dog that is 10% above its ideal weight, is overweight.

She is on Hills I/D because of a sensitive stomach and for health reasons she now needs to loose weight. The owners have reduced the feeding amount from 1/3 can in the morning + 1/3 can in the evening + 1/8 can as a late snack to 1/4 can already. So from a 80% filled can, she is now on 25% of a can daily.

The chihuahua is the smallest breed of dogs in the world. The breed standard for this dog specifies a maximum weight of 6.0 lbs (2.7 kg). The dog in question is a mix with a dachshund which comes in two sizes. This, plus the fact that I cannot judge the dog’s shape and waistline, makes it difficult to judge the extent of obesity. I’m for now assuming the ideal weight is 7.5 lbs (or 3.41 kg); the weight she used to have.

A dog’s basic energy requirement depends on his size. As small dogs have relative to their weight more skin surface they need more food (relatively speaking!) compared to large dogs. Suppose dog B is twice as big as dog A, that doesn’t mean dog B needs twice as much food!

I’ve calculated the maintenance energy requirements for a 7.5 lbs dog at 1381 kJ per day. Now this is for a dog that is reasonably active. For a dog that needs to loose weight this can be reduced to 50% so 690 kJ daily. An average dog food has about 1500 kJ per 100 gram (check this for your brand!) and 690kJ then converts to 46 gram dog food a day.

Feed this daily amount at multiple (4 to 5) small portions a day. This way the ‘engine’ of your dog keeps running. Most overweight dogs have a slow metabolism and don’t burn off fat very fast. Feeding multiple times a day helps to prevent them from going further into ‘energy saving mode’.

So at the same time, work on the other side as well. Reduce calorie intake and stimulate the burning process by gradually increasing the amount of exercise and play your dog gets. This helps to burn off the excess fat and also helps preventing muscle loss (you want her not just to loose weight; you want her to loose the excess fat tissue).

Chihuahua dogs are often carried around, which may make them susceptible to weight gain. Perhaps also the cuteness factor of these dogs contributes as they may receive more treats and snacks then an aggressive looking dog. I can’t tell of course in this case, but the required amount of kiloJoules a day is the total amount, so food plus snacks!

Now with a dog that has 33% more weight than is good for her health, you need to visit a veterinarian. Ask for a weight reduction diet that will also fit her sensitive stomach issue. This diet will have lower fat percentages compared to regular dog food, but it must have enough essential fatty acids. To compensate for the reduced fat percentage, this dog food should be higher in protein (which cannot be stored as energy reserves in the body) and higher in crude fiber (about 7-8 %). Meat should be the first listed ingredient and not corn. Check the amounts of kJ per 100 gram to calculate the right feeding amount for your dog.

Weigh your dog every two weeks. If there is a result, great! She didn’t get the excess weight overnight, so don’t expect her to loose it too rapidly. If she hasn’t lost any weight, then reduce the amount fed by one-third, provide more exercise and be persistent.

You might also want to ask your vet whether your dog is a good candidate for the doggie diet pill, which can be of extra support. This medicine (dirlotapide) should be prescribed for a limited period only, because of the side effects.

For more information about overweight dogs and dog obesity, visit Best Dog Food Guide.