Most of the following information involving specifics of requirements comes from "Small Animal Clinical Nutrition, 4th ed." by Hand, et al. From
www.vetinfo.com
There is no clear guideline for when to switch from puppy food to adult
Food, but the switch should be made about the time that the puppy's bone
Growth (including increasing bone density) stops. This varies from breed to
Breed but probably is somewhere between 10 months and a year of age.
The most common mistake made in feeding puppies is to feed too much
Calcium. This is easy to do. The second most common mistake is probably
Feeding foods with improper calcium/phosphorous ratios. This isn't usually
Due to a problem with the commercial food, it is usually due to feeding
Supplements or snacks that contain either calcium or phosphorous and
Unbalance the ratio found in the food.
The first thing that you have to understand about feeding calcium is that
The percentage of calcium required in the food is very dependent on the
Amount of energy that the food provides. A food that provides a high degree
Of energy will require a higher amount of calcium and a food that provides
Smaller amounts of energy should have lower amounts of calcium. I have not
Seen a figure for the maximum amount of calcium in very high energy foods
But if a dog food provides less than 3.8 kilocalories of metabolizable
Energy per gram of food (< 3.8kcal/g ME) then the calcium level in the
Food should not exceed 1.5% on a dry matter basis.
To convert the calcium percentage in dry dog foods to a dry matter basis,
Multiply by 0.9 (90%) to convert to dry matter from the label (as fed)
Percentages.
For canned food it is reasonable to multiply the percentage of an
Ingredient on an "as fed" basis to a dry matter basis by multiplying it by
4. This is not as precise as subtracting the percentage of water to figure
Out the dry matter and then dividing the percentage on the label by the
Percentage of dry matter but it is easier.
The new big breed puppy foods have higher calcium levels than adult dog
Foods. They also have a lot more energy per gram (or cup, or any other
Measure). So the puppy eats less of the food to meet its energy
Requirements. This is important to realize, because if a puppy is fed an
Adult dog food that has a lower amount of calcium, but it has to eat two or
Three times as much of the food to meet its energy requirement, it will
Actually consume more calcium from the adult food, even though it has a
Lower calcium content on a percentage basis. Puppies need about 1% calcium,
On a dry matter basis, for foods that provide 3.5kcal /g ME (about the
Average).
You might have to call the dog food company to get the number of
Kilocalories per gram of food, or you can check out Ohio State's web site
On nutrition, which might have your dog food listed.
It might be possible to cause problems with hip dysplasia,
Or other orthopedic disorders, by feeding excessive calcium, but the
Biggest problem is feeding excessive calories. The reason that the large breed puppy foods are a good idea is that they have enough calcium and energy to allow you to feed adequate amounts of calcium while meeting the puppy's energy needs, without making
Him overweight.
Once the growth phase is over the calcium requirements drop. On the other
Hand, the risk of feeding too much calcium and causing orthopedic problems
Also drops some. Adult dogs only require about 0.6% calcium on a dry matter
Basis for foods providing 3.5 kcal/g ME
For a Rottweiler 12 months is a good age to change. You should make the transition
Gradually, taking a week or so to switch entirely.