Managing a dog’s health certainly includes preventive care with regular veterinary visits, but understanding the role of “proactive nutrition” can also help to improve their quality of life and longevity. Many dogs, because of the role of genetics, are “at risk” for developing certain diseases. Proactive veterinary care means identifying at-risk patients and understanding the important role of nutrition and supplements in these patients developing these diseases.
An excellent example of this is seen with giant and large breed puppies that are well known to have the genetic tendency to develop osteoarthritis, which is termed developmental orthopedic disease (DOD). Nutritional factors that impact rate of growth and bone/joint development play an important role in DOD, and deficiencies can result in orthopedic diseases such as hip and elbow dysplasia, osteochondritis dissecans, heritable cruciate disease, hypertrophic osteodystrophy, Legg-Calve-Perthes disease, and cervical spondylomyelopathy (wobbler’s disease). Recognizing puppies at-risk for DOD and utilizing what is known about the role of specific nutrients can enable veterinarians to use proactive nutrient supplementation to reduce the risk of these orthopedic diseases. The list of dog breeds at risk for DOD includes Great Danes, Newfoundlands, Burnese Mountain Dogs, Saint Bernards, Rottweilers, Golden Retrievers, and Labradors.1-11
Food Gram Scales, the Feeding Plan, and Nutrition for Dogs
Proactive nutrition includes an appropriate feeding plan. Veterinarians should discuss with owners the importance of providing measured amounts of an appropriate diet for slow growth and optimal body conditions score. More exact intake is achieved by having owners weigh the puppy’s meals on a food gram scale rather than using measuring cups or food scoops. Appropriate treats should be discussed with attention to both the additional calories and nutrient content. The importance of controlling growth and body condition score (BCS) was demonstrated in a lifetime study of 48 Labradors at-risk for orthopedic disease. The dogs that were in the diet restricted group, consuming only 25 percent less calories, had a statistically longer lifespan, i.e. 11.8 years versus 13 years.20
Avoiding Overnutrition for At-risk Puppies
One of the key components of concern for at-risk puppies are calories. Overnutrition – providing too many calories – results in an overweight puppy with a rapid rate of growth and abnormal bone development. Intake of pet diets with high energy density, i.e. high kilocalories per kilogram, should be avoided. Premium pet diets with a high fat content should also be avoided as they will have an increased energy density. High-energy diets promote increased levels of growth hormone, insulin-like growth factor, thyroxine, and insulin which directly impact the puppy’s rate of growth and development.
Besides overnutrition due to high energy diets, simply feeding too many calories can be problematic. These at-risk puppies should have controlled intake of all food and treats as over-feeding and free feeding can also result in overnutrition. Current recommendations are to feed a diet with a reduced energy density (3500 to 4000 kcal/kg) and a moderate fat level (12 to 15 percent on a dry matter (DM) basis. The daily intake of diet and calories are controlled to obtain slow growth while maintaining a BCS of 4/9 for an at-risk puppy rather than the typical ideal BCS of 5/9. The most critical period for this type of controlled caloric intake is believed to be at least 12 months of age, if not 18 months for the giant breeds.1, 5-7
Using both body weight and BCS is needed to manage proper nutrition for dogs, both adults and growing puppies. It is preferred to use the 9-point system of body condition scoring. BCS assesses the dog’s body fat, where a body condition of 5/9 meaning 20 percent of the dog’s weight is fat. This is ideal.
Nutrition for Dogs and Developmental Orthopedic Disease
Nutrients that play a role in DOD are calcium, phosphorus, and vitamin D which must be fed in appropriate amounts and be balanced to assure optimal bone growth and development. Excess intake of especially calcium and other minerals can predispose these at-risk puppies to osteochondrosis. The bones of an overweight, growing DOD puppy experience increased weight loads and muscle/ligament pull, resulting in abnormal joint development. Acute joint inflammation may occur which can result in disruption in normal cartilage and subchondral bone development. Inflammatory mediators perpetuate the cycle of degenerative joint disease, eventually resulting in the phenotypic signs of osteoarthritis.1, 6-9, 12-14
The appropriate intake of calcium is critical in the rapidly growing puppy and has more impact than the diet’s calcium to phosphorus ratio. Feeding a diet too high in calcium results in increased calcium retentions in the body whereas a diet too low in calcium results in enhanced absorption of calcium. Both excess calcium retention and absorption can result in improper bone development.15 Vitamin D levels should also be appropriate for growth as high plasma levels may be a pathological factor responsible for increases in skeletal disease. In studies thus far, the differences in protein intake have not been shown to affect the occurrence of disturbed skeletal development in young giant or large breed puppies.15-18
Supplements and the At-risk Puppy
Veterinarians should inform owners of at-risk puppies to avoid multivitamin supplements and top dressings that may contain additional calcium or other nutrients. Similar to treats, pet supplements should be carefully evaluated to assess their contribution to the puppy’s caloric and nutrient intake. Studies do suggest that the proactive recommendation of supplements containing the omega-3 fatty acid eicosapentanoic acid (EPA; 20:5n-3) and docosahexanoic acid (DHA: 22:6n-3) may be beneficial in dogs at risk for orthopedic diseases. In one study, omega-3 intake increased lean body mass and resulted in greater cartilage formation biomarkers in large breed dogs.21 Another study using a canine cruciate model demonstrated intake of a diet with an omega-6 to omega-3 ratio of 1:1 resulted in decreased inflammation, increased weight bearing, and decreased radiographic changes of osteoarthritis.22 Veterinarians recommending omega 3 supplements when considering nutrition for dogs for at-risk patients should account for their contribution to total calorie intake to prevent weight gain.
The Appropriate Pet food for the At-risk Puppy
Feeding high-fat, energy-dense diets can be problematic because they can promote rapid growth. If the amount fed is reduced to slow growth, this can potentially result in deficiencies in other important nutrients. For example, deficiencies in other nutrients that play a role in proper skeletal developments such as copper, zinc, magnesium, manganese, and vitamin A can occur with restriction of a high energy diet.
The recommendation to feed giant and large breed puppies pet diets labelled for adult maintenance are also inappropriate. A growing puppy may need to consume more of an adult maintenance diet that can result in inappropriate amounts of other important nutrients. For example: considering calcium intake in an at-risk puppy requiring 1600 kcals/day, a puppy growth diet might provide 4.0kcal/gram and 1.5 percent calcium, while an adult maintenance diet might provide 3.2 kcal/gram and 1.5 percent calcium. Then the puppy would require 400 grams of the puppy growth diet, intaking 6.0 mg calcium, or 500 grams of the adult diet, intaking 7.5 mg of calcium.
An optimal diet for these at-risk breeds is one designed to meet the nutrient requirements of growth of a large breed puppy that has a defined and controlled calorie density while ensuring proper calcium, phosphorus, and vitamin D intake and balance. Veterinarians should use “proactive nutrition” to discuss the importance of proper calorie and nutrient intake to owners of at-risk puppies. Utilizing proactive nutrition, veterinarians should recommend appropriate pet foods for DOD puppies which will have the specific AFFCO labeling:
“PET FOOD BRAND is formulated to meet the nutritional levels established by the AAFCO Dog Food Nutrient Profiles for growth/all life stages including growth of large-size dogs (70 lbs or more as an adult)”19
Using appropriate diet, treats, supplements, and feeding plan, today’s veterinarians can successfully use proactive nutrition for dogs to optimize the growth and development of giant and large breed puppies to lower the risk for orthopedic diseases.