My vet recommends 4 months or 40 pounds on puppy formula, which is about one 20# bag for one pup. I think they really need that extra nutrition that is in the puppy formula.
The growth rate in the first 16 weeks affects the outcome of hips more than any other time. The femur heads form during those weeks and the rate of growth is tremendous. The puppy is 15 - 20 times bigger than he was when he was born.
Slowing the rate of growth in those first 16 weeks when the body is rapidly converting blood calcium to bone is best. Also, puppy formulas that are high in calcium can slow the body's ability to make bone from blood calcium much in the same way eclampsia (low blood calcium) is triggered by feeding too much calcium to a lactating bitch.
The body that is over supplied with calcium in the diet does not work as hard to convert the dietary calcium to blood calcium which builds bone.
The same principal works in reverse when you cut a dog's kibble to trigger weight loss. The dog's body responds by slowing its metabolism to conserve fat and calories for what it sees as a food shortage. So either a food glut or shortage changes the dog's natural metabolism.
The Eukanuba study found that calcium levels below 1% greatly reduced the incidence of CHD & OCD. You'd think the opposite would be true. It also found that fat puppies on low calcium had less joint disease than thinner pups on high calcium did. Thin pups on low calcium had the least joint problems. Eukanuba’s large breed formula was made as a result of that study and many other companies have since reduced the fat and calcium in their puppy formulas. My Vet calls calcium ‘OCD in a bottle’.
Some have said they ‘feed up’ their pups and only those that can stand the pressure of those diets are kept in the breeding program. The fast growth rates, they believe, reveals the CHD or OCD genes where a slow growth may mask it. Maybe. But in practice growing puppies quickly to see whose joints hold up will mean breeding many more litters than I am willing to do.
I feed an adult formula that pushes the envelope on calcium (1%) because I like my coats better on the food. But if your puppy formula is the traditional type, the sooner they are off puppy food the better.
Now this is curious since I talked to another dog food manufacturer about Eukanuba's below 1% calcium and he told me that he heard about stress fractures with puppies fed this formula due to not enough calcium.
The FDA site recommends a minimum of 1% calcium in puppy foods. This is one of the reasons I switched from Eukanuba LB puppy food to Proplan which has 1.1%. The Proplan adult has 1.0%.
I just switched to Euk. Lg. Br. Puppy this year. I used to use an adult food that had 1.3 % calcium, but the correct ratio of Cal. to phos.. I had talked to the mfg. to be sure.
I had a puppy last year who had one hip that was not great - not dys. but not as good as the other one. I started to do some research and the nutrionist that I talked to said the the newest studies say the calcium for puppies should be 1% or less. She also told me that Labs don't utilize fat as well as other breeds, so the % of fat should be less than what I was feeding - which was 18%.
I tend to keep the puppies a little chubby - which she advised was not the best thing to do. Keep them a little leaner while they are growing.
The only thing we didn't cover - was how long to keep them on puppy food - such as the Euk..
Their bones/joints are still remodeling for some time. She recommended Cosequin for the condroitin/gluco. combination to help the condrocytes (cells) to rebuild.
I require puppy buyers to feed 1% or less calcium food for one year and to keep puppies gaining at my recommended rate for the first 8 weeks after they go home. The pups look thin for two months, but eventually get the size and substance their genes call for. Most owners follow my advice. There are those who will over feed or change to high calcium foods. I hold my breath and hope the puppies have bomb proof genes.
I keep my pups pretty thin until they are 16 weeks when I prelim w/o anesthesia and start filling them out. I grow them faster than my pet owners do because I want to compete in Sweeps.
Laura, I would be interested in reading any studies regarding stress fractures. Did the dog food company cite anything? I heard about a study of wolves in the wild. Researchers estimated the caloric intake and vitamin levels of the prey they caught. There were some days pups didn't get any calories. If stress fractures occurred it wasn’t mentioned. As I recall the study found the HD percent was 15%.
During weeks 8-12 puppies should gain between 1.25 - 1.75 pounds per week. During weeks 13-16 they gain between 1.75 - 2.25 per week. After 16 weeks puppies can carry a little fat as long as it is not sloppy fat.
Consistently gaining more than the high end goals will result in a fat puppy. Fat is stored because the puppy has used all he can for growth and energy and has to put the excess food somewhere. That means the puppy is growing as fast as possible.
I send puppies home on 1/2 cup 3 times a day but a week later the owners are usually on different measurements. A busy puppy in an active family may eat twice what a laid back pup will eat but both can stay on target. Weighing and adjusting is what matters.