I'm an experienced veterinarian and I feel passionately about what pets eat. It really matters that pets have diets which are made of good wholesome foods.
Each dog or cat is an individual, just like us. They need a diet that is right for their age and health issues. It is important to choose a food which is appropriate for your pet's age group .
Puppies and kittens need high protein diets with high calorie content because they are growing quickly, using lots of energy but can only eat a small amount at any time. I always advise owners to feed their puppy at least 3 or 4 meals a day even though they seem to spend a lot of time napping!
Older pets need less calorically dense foods and often benefit from joint supplements such as glucosamine. And resist the temptation to overfeed them. Remember they don't open the refrigerator!
Just like with people, a good diet goes a long way towards keeping pets happy and healthy.