Guest article by:
Dr. Kara Amstutz, DVM, CCRT, CVPP, CVA
How to Feed Large and Giant Breed Puppies for Joint Health
Osteoarthritis has been shown to affect at least 20% of dogs over one year of age, with the incidence increasing up to 80% as pets age. While veterinary rehabilitation therapists have many tools to deal with chronic osteoarthritic pain including medications, supplements, therapeutic exercise, weight loss programs, manual therapy, acupuncture, and modalities such as LASER and Extracorporeal Shockwave; the simple truth is, we often don’t get the opportunity to treat this condition until the joint damage has already been done. Sadly, we also understand that osteoarthritis is a progressive condition that will likely get worse as the pet ages.
Canine osteoarthritis has many inciting causes and contributing factors including genetics, trauma, age-related degeneration of the joint structures, obesity, and overuse injuries. One common cause of osteoarthritis is Developmental Orthopedic Disease or DOD. Conditions such as hip dysplasia, elbow dysplasia, and osteochondrosis desiccant (OCD) fall into this category.
By far, the largest risk factors for DOD include the following:
1) Large or giant breed dogs
2) Free choice feeding, especially very energy dense foods
3) Excessive intake of Calcium and Vitamin D foods, treats, and supplements
Large or Giant Breed dogs
Dogs that will weigh more than 55 pounds at their adult size are considered a large breed dog. A dog weighing over 99 pounds is considered a giant breed. Why are these breeds at a higher risk for DOD?
All puppies have a rapid growth phase early in life, however, while the rate of growth in smaller dogs slows down by 6 to 7 months of age, large/giant breeds continue for months beyond that. Growth plate closure occurs later in large/giant breed dogs as well. Typically by 12 months of age growth plates have closed in smaller dogs, but giant breed dogs may not close until 18 months of age.
Until the growth plates have closed, this area is considered to be unstable and at risk for trauma which can lead to anatomic deformity, incongruent joints, and ultimately osteoarthritis.
Genetics play an important role in DOD as well. Certain breeds such as Labradors, Great Danes, and German Shepherds have higher risk of developing joint problems. Vigilant breeding programs with screening for these conditions are of utmost importance for the reduction of passing of genetic defects to future generations. Predictive DNA tests have been developed, but are yet to be validated as a useful tool.
Feeding Methods
Free-choice feeding is easy and convenient for pet owners but we know this feeding method increases the risk of overnutrition which sets in motion the increased incidence of DOD, obesity, and a variety of other health conditions. A landmark study compared dogs being fed a calorie-restricted diet versus free choice over a lifetime. The results of the study demonstrated that the calorie-restricted fed dogs had reduced risk and severity of many diseases, and on average lived two years longer.
Puppy foods are typically very high in energy and fat to assist with proper growth, but, if too much energy is taken in, the risk of overstress to the skeletal system increases. The dog’s body weight increases at a rapid speed, however, the bone development can’t keep up to support the burden. This imbalance promotes damage to the skeletal system such as OCD lesions within joints. Fast growth also enhances bone remodeling which can result in decreased bone density. So, you have a puppy with excess weight and weak bones, a recipe for joint problems later in life.
Overnutrition also influences a variety of hormones such as growth hormone, IGF-1, T3 & T4, and insulin. Alterations in the concentration of these hormones have been shown to affect the stability of growth plates in dogs. As previously discussed, large/giant breed dogs already have an inherent risk with growth plate stability, which makes these hormonal influences of even more concern.
Calcium and Vitamin D levels
Many studies have elucidated the link between mineral imbalances and DOD. The most likely culprits are calcium, vitamin D, and phosphorus. These minerals, along with other hormones, must maintain a delicate balance to allow for proper growth while avoiding pathology. Too much or too little can lead to serious health conditions.
Calcium is the most important element of bone mineralization and is vital for proper skeletal development. Large/giant breed puppies fed foods high in calcium have an increased risk of DOD, most notably OCD lesions on weight-bearing sites (articular joints such as shoulder, elbow, and tarsal joints) and non-weight-bearing sites (rib growth plates). Delayed skeletal maturation and growth of the long bones, angular limb deformities, panosteitis, osteochondrosis, and Wobbler’s syndrome have also been found in puppies fed high calcium diets.
Calcium and phosphorus levels are always considered together and should be maintained at a specific ratio of 1.1: 1 up to 2:1. If phosphorus is too low compared to calcium, growth plates may be widened. If phosphorus is too high and calcium is low, a condition called nutritional secondary hyperparathyroidism develops which leads to very weak, soft bones, and pathologic fractures.
Vitamin D helps to regulate calcium metabolism by increasing the amount of calcium absorbed from the gastrointestinal tract. Puppies passively absorb 70% of total dietary calcium from the small intestinal tract. They are less able to regulate nutrient absorption compared to their adult counterparts. Therefore if a puppy is taking in too much Vitamin D, they are more likely to absorb too much calcium, catapulting the cascade of problems excess calcium can create. Vitamin D deficiency combined with low calcium intake can lead to rickets and fibrous osteodystrophy where connective tissue replaces mature bone.
Well-meaning pet owners supplementing their puppy’s diet with the desire to improve their pets odds of being strong and vital, can sometimes unknowingly increase the pet’s risk of DOD, which can lead to osteoarthritis and a lifetime of pain.
NOTE: It is not recommended to supplement growing large/giant breed puppies that are fed a commercially made diet.
Recommendations for feeding large/giant breed puppies
Limit calorie intake to slow growth velocity:
Feeding a specific amount of calories per day based on the dog’s daily energy requirements (DER) and age can assist in slowing down the growth velocity. To determine this amount, the resting energy requirement (RER) is calculated:
RER = (70 x bodyweight in kg) 0.75
Puppies age 2-4 months: DER = 3 x RER
Puppies age 4-12 months: DER = 2 x RER
This will give a daily calorie amount used as a starting point. However, rates of growth can vary from puppy to puppy. Therefore, frequent evaluation of body condition score (every 2 weeks in rapidly growing dogs) should be used to determine if the calorie amount should be increased or decreased. It is helpful for pet owners to know how to evaluate their pet’s body condition at home as a tool for feeding amounts as well. A body condition score of 4 out of 9 is the goal. We want slow, sustained growth that is safe for our large/giant breed puppies.
Food Selection:
Feeding a diet that is appropriate to the puppy’s life stage and breed is important. A diet that is specifically formulated to consider the unique nutritional requirements of large/giant breed puppies and has passed standardized feeding tests established by AAFCO is preferred. Large breed growth diets are less energy-dense, thus reducing the risk of overfeeding. They also have appropriate calcium and phosphorus levels.
Key Nutritional Factors for large/giant breed puppies during growth:
| Factor | Dietary Recommendation |
|---|---|
| Energy Density | 3.2 to 4.1 kcal/g |
| Fat | 8.5-17% Dry Matter |
| Protein | 22-32% Dry Matter |
| Calcium | 0.8-1.2% |
| Phosphorus | Based on amount of calcium to maintain recommended ratio (see below) |
| Calcium - Phosphorus ratio | 1.1:1 to 2:1 (lower end is preferred) |
| Supplements | NONE recommended if commercial food is fed |
If feeding a homemade diet, consult a veterinary nutrition specialist for assistance in making sure the mineral amounts are properly balanced. To learn more please visit: www.acvn.org/nutrition-consults/
A Final Note of Caution
In the past, it has been recommended by veterinarians and breeders to transition large/giant puppies to adult dog food at an early age to help slow their growth. Adult dog food is generally less energy-dense, thus, less calorie-dense.
However, this is risky because the energy density and calcium levels of the thousands of adult dog foods available are so variable. Some may be higher or lower in calcium and calorie density than the growth food the pet was just transitioned away from. Depending on the energy density and calcium concentration, the puppy may actually take in even more calcium than they would have if they were just kept on puppy formula.
The best advice is to continue the large/giant breed puppy on a large breed growth formula until they reach skeletal maturity.
References:
Oettmeier R, Arokosi J, et al. Quantitative study of articular cartilage and subchondral bone remodeling in the knee joint of dogs after strenuous running training. Journal of Bone and Mineral Research. 1992 7:S419-S424
Johnston S.A. Osteoarthritis: joint anatomy, physiology, and pathobiology. Vet Clin North Am Small Anim Pract. 1997 27:699-723
Budsberg S, Bartges J. Nutrition and Osteoarthritis in Dogs: Does it Help? Vet Clin North Am Small Anim Pract. 2006 36:1307-1323
Manz, E, et al. Prospective evaluation of a patented DNA test for canine hip dysplasia (CHD). Plos One 2017; 12(8): e0182093.
Richardson D, et al. Developmental Orthopedic Disease of Dogs. In: Hand M, Thatcher C, et al. Small Animal Clinical Nutrition, 5th ed. Topeka, KS: Mark Morris Institute; 2010.
Von Pfeil D, DeCamp C. The Epiphyseal Plate: Physiology, Anatomy, and Trauma. CompendiumVet.com Veterinary Learning Systems July 2009
Tryfonidou M, et al. Intestinal Calcium Absorption in Growing Dogs is Influenced by Calcium Intake and Agee but Not by Growth Rate. The Journal of Nutrition. 2002 132:3362 – 3368.
Dobenecker B, et al. Mal-and overnutrition in puppies with or without clinical disorders of skeletal development. Journal of Animal Physiology and Animal Nutrition. 1998 80:76-81