Many dogs are puppies from birth until 1 year of age, however, some breeds can grow for up to 24 months. An adult dog is generally classed from age 1 to 7, but this not a firm answer and can be determined by the animal’s health and activity level.
Large breed foods should generally be used on dogs 50lbs and over. This is most important in puppyhood. Large breed puppies generally grow more slowly than smaller breeds, creating a need for a lower protein and lower fat food. This helps to slow down the growth of joints to fight the formation of arthritis and other joint problems generally associated with larger breeds. Large breed adult foods can also be helpful, particularly if a larger content of glucosamine and chondroitin is present.
This is not such an easy question to answer. Companies like Royal Canin put years of research into the creation of their breed specific formulas and there is merit in this. It takes much of the thinking out of the hands of the owner, addresses some common health issues on particular breeds, alerts them to things they ought to watch out for with their dog/cat’s health
This is one of the most multifaceted questions someone could ask. Some of the main considerations are meat, carbohydrates, vegetables, fruits, fibre, fatty acids, and supplements.
Meat/Proteins: There are many different protein sources available, including beef, chicken, turkey, bison, venison and many types of fish. Chicken is the most common and considered to have the highest palatability by most dogs and cats. These types of meats can be broken down into whole meats and by-products.
By-products are generally regarded as lesser than whole as they can include organs, bone, heads, feathers, beaks etc. This is not always the case as some by-products face more careful screening than others. Another factor is whether the meat is fresh or a meal. Fresh meat is placed into the recipe still containing waters present in the body. This can shrink in the preparation process and can be deceiving when a meat is listed as the first ingredient, but really comes out as the 5th or 6th after the water has been removed. Meals are meats that are pre-dried before processing and look much like powder. Meals can vary in quality and both by-products and whole meats can be made into meals. Some argue for their being better than fresh meat because of their density, while others argue that they are lesser because more processing is used in the preparation of food.
Carbohydrates: Carbohydrates come from a variety of sources, including rice, barley, corn, wheat, oats, and many types of potatoes including yams. Some are considered more hypoallergenic than others and some more digestible. Corn and wheat are generally considered less healthy for dogs and cats. This is subject whether it is ground, whole or separated into gluten. The more times corn is ground, the easier it is passed through the system, but it is not as digestible as rice for example. It also contains some protein. Wheat frequently causes allergic reactions in dogs and cats and is generally avoided in most premium and super premium foods. The other sources of carbohydrates are good, but can occasionally cause allergies in select animals.
Vegetables and Fruits: Many of the more premium types of foods contain vegetables as a natural source of vitamins, minerals and other health benefits. Fruits can fall into a similar category. An example of this is the use of cranberries as a source of anti-oxidants and a healthy urinary tract.
Fibre: Levels of fibre are important and different levels are required by different breeds and ages of pets. For example, higher levels of fibre are often used in weight management diets to stimulate the bowels and improve weight loss. Dogs with diabetes can benefit from higher levels of fibre than regular dogs as well.
Fatty Acids: This accounts for the levels of omega 3, 6, and 9 found within a particular food. These can be derived from fish, soy, canola and other types of oils. Fatty acids, like with humans, contribute to a health coat and healthy skin. Foods vary on their levels of fatty acids.
Supplements: This includes vitamins and minerals. It also includes glucosamine and chondroitin which help to maintain healthy bones and joints. These can be quite expensive. Generally premium and super premium foods contain more supplements and strive to derive them from as natural a source as possible.