When deciding to have your dog neutered or spayed, it is important to be aware of the potential advantages and disadvantages of this procedure, so that you can prevent or successfully address them.

The advantages of neutering

• Absence of sexually transmitted diseases.
• Reduction of aggression between male dogs when competing for a female.
• Prevention of testicular tumours.
• Some dogs become easier to handle and more sociable after neutering.
• No heat cycles or pregnancies.
• Prevention of uterine tumours and pyometra.
• Reduced risk of certain mammary gland tumours.

The disadvantages of neutering

• Surgical neutering is a surgical procedure with all the associated risks.
• Possible oestrogen-dependent urinary incontinence.
• Possible tendency to weight gain, especially in dogs that do not get much exercise.

Feeding a neutered dog

After neutering, the owner may have to deal with new nutritional needs for the dog. Some studies suggest that neutered dogs are more likely to experience changes in their ideal body weight than unneutered dogs. It is estimated that female dogs can build up more fatty tissue, with twice the risk of intact female dogs. Male dogs also tend to build up excess fat after castration. This is due to a reduced energy requirement but a greater appetite. That is why nutrition is very important for sterilised dogs.

Why does the diet for neutered dogs change? Neutering changes the dog's hormonal balance and, with it, its metabolism. The cessation of production of female sex hormones, oestrogens, leads to an increased feeling of hunger, as these hormones have a regulating effect on appetite and basal metabolism. The same applies to males, who change their hormonal balance after castration and reduce their activity. Someone who eats more than is necessary will logically gain weight.

Preventing obesity

Overweight in dogs not only has aesthetic consequences, but can also lead to conditions such as diabetes, hyperadrenocorticism, hypothyroidism, heart problems, digestive disorders, pancreatitis and excessive strain on ligaments and bones, which can reduce life expectancy.

A specific diet can limit the change in ideal body weight. After sterilisation, energy requirements change, but not those for vitamins and minerals, so a diet with smaller portions not only means fewer calories for the dog, but also a lack of important nutrients, which can lead to deficiencies. A reduced amount of food can also increase feelings of hunger and lead to persistent begging from the dog.

So instead of offering a smaller portion of the usual food, it is better to choose food that is lower in calories but still provides enough nutrients to meet the dog's needs.

Even after sterilisation, each dog has its own individual nutritional needs, depending on its breed, age, sex, level of physical activity and health status. It is important to discuss this with your vet, who can draw up a specific feeding plan based on the dog's individual needs.

The ideal body weight

The owner plays an essential role in recognising whether the dog is in good shape or showing a change in ideal body weight, and should be trained to assess the Body Condition Score (BCS) and Muscle Condition Score (MCS) to evaluate the current condition and changes over time.

BCS assesses body fat using a 5- or 9-point scale, with the ideal goal being to achieve a score of 3 out of 5 or between 4 and 5 out of 9. When the dog is at its ideal weight:

• When viewed from the side, the ribs are not visible from the outside and can only be felt slightly when touched.
• When rubbing the back, no bones are felt and the back appears to be a continuous line.
• When viewed from above, the dog has the characteristic hourglass appearance with a taper at the belly.

MCS evaluates muscle mass by visual inspection and palpation over the temporal bones, shoulder blades, lumbar vertebrae and pelvic bones.

Finally, to limit changes in the ideal body weight after sterilisation in dogs, it is not enough to change the diet alone; it is also necessary to provide the dog with daily exercise.