Adult dog food is not the same as puppy dog food in many ways. This is because of the different health and survival needs that exist during the different age groups.
Puppies need help growing in terms of size and developing in terms of senses, cognitive function and even gut health.
Adults on the other hand need more support with survival as growth has usually reached the end point in this case. Their food therefore focuses more on providing nutrients necessary to maintain energy levels, support muscle function and provide useful micronutrients like vitamins and minerals.
These needs are reflected in the main difference between puppy and adult dog food which is in the composition. For puppy food, there are usually higher levels of development boosters including fish oils for brain development, vitamins for boosting immunity and skeletal supplements like calcium and glucosamine for their growing bones. They also have higher proportions of protein with 22% or more of the calories being from protein sources.
Adult dog food, however, has 15% to 18% of calories from proteins, more carbs and few special compounds unless with specialized formulas.
In addition to this, there are also differences between puppy and junior dog food. Junior dog food is meant for pooches over 3 months for large breeds and 6 months with smaller doggies.
For the most part, junior dog food is similar to puppy food in that it is meant to offer both growth support. However, it is also designed to match the higher energy needs of the older and more active dog and therefore tends to have more calories per serving than the puppy dog food.