Written by Dr. Jill Cline, Ph.D.
All growing puppies, regardless of their breed, have the same basic requirement for a nutritious diet that supports optimal growth and development. However, the enormous range in size between the smallest and largest dog breeds results in different rates of growth and skeletal development during the first year of life. Feeding a food that is designed for large breed puppies and using proper feeding practices will help you to support healthy growth and long-term vitality for your large-breed puppy.
The Large and Giant Dog Breeds
Dogs come in an enormous variety of sizes and body types. For example, the adult weight of a Great Dane may be 30 times the adult weight of a Chihuahua, with many breeds existing between these two extremes. Generally, large-breeds are considered to be dogs whose mature adult weight is between 50 and 100 lbs, while “giant” breeds are dogs whose mature weight is more than 100 lbs. Some currently popular large breeds include the Labrador Retriever, Golden Retriever, Weimeraner, Rottweiler, Bernese Mountain dog and German Shepherd Dog. Well known giant breeds include the Great Dane, Newfoundland, Saint Bernard, and Akita. If you have a mix-breed puppy who is known to have large or giant breed parents or who you anticipate will weigh more than 50 lbs as an adult, your puppy is also included in this category of dogs.
Growth and Development
All puppies have an enormous amount of growth to accomplish during a relatively short period of time. For example, a healthy Golden Retriever puppy who weighs 14 oz at birth can grow to be 65 lbs within her first year of life, constituting a 70-fold increase in size! The most rapid growth occurs during the first 6 to 8 months of life. After this age, your puppy’s rate of growth gradually slows until he reaches maturity. Medium-size breeds attain mature size at approximately 12 to16 months of age, while the large and giant breeds reach mature adult size between 18 and 24 months of age. Although your young large breed dog may appear “full-grown” when he is about one year of age, his body and skeleton are not completely developed or mature until months later. This fact has implications for the type of diet that is fed, the feeding practices that are used and the exercise that is provided to young large-breed dogs.
The Importance of Optimal Growth Rate
It is normal and healthy for a large breed puppy to attain maturity at 16 months or later. Conversely, large breed puppies who are growing too rapidly may mature earlier than what is normal for their breed. Rapid growth rate during the first year of life causes accelerated tissue and bone development, higher body fat, and a heavier body weight. Accelerated bone development results in larger but less dense (and less strong) bones and a heavier body weight places added stress on the developing (and weaker) bones. Together, these subtle but important changes contribute to an individual dog’s susceptibility to several types of skeletal disease. These include hypertrophic osteodystrophy (HOD), osteochondritis dissecans (OCD) and hip dysplasia.
It is true that genetics plays a role in each of these disorders. However, nutritional factors that support maximal rate of growth also contribute to increased risk. Providing a diet that is very calorically and nutrient dense and feeding for a “plump” body condition can force a large breed puppy to maximize his growth rate and mature at an age that is earlier than what is normal for his or her breed. Because of the increased risk for skeletal disease, feeding your large breed puppy for maximal growth rate and early maturity should be carefully avoided. Puppies who are fed to attain optimal growth rates during the first 2 years of life will attain their normal adult size at a healthy rate that is normal for their breed and that supports strong bones and a lean and well muscled body condition (see Box 1).
Selecting the Best Food for your Large Breed Puppy
Puppies have a high demand for energy, protein, and all of the same essential nutrients that are needed by adult dogs, but at slightly higher levels to support growth. Several commercial foods have been specifically formulated for large and giant breed puppies. The following nutrients should be considered:
• Caloric content: It is now clear that growing large breed dogs should not be overfed. Even mild overfeeding (i.e. for that “plump” body type) leads to an accelerated growth rate and increased risk of skeletal disease. Suitable foods for large and giant breed puppies have slightly reduced energy densities when compared with other puppy foods. Because fat contains more than twice the calories per gram of carbohydrate or protein, the energy density of a large breed food is lowered through a moderate reduction in fat content. A recommended nutrient profile for a diet formulated for growth in large and giant breeds is one that contains between 12 and 15 percent fat and a caloric density of less than approximately 400 kcal per cup.
• Protein: The protein requirement of growing dogs is higher than the protein requirement of adults because growing puppies need more protein to build the new tissues that are associated with growth. Although total energy is reduced in foods for large breed puppies to control rate of growth, the protein level should still contribute at least 25 % of the calories to support healthy tissue growth and development.
• Calcium: Diets for all growing dogs should contain optimal, but not excessive amounts of calcium. Contrary to the beliefs of some dog enthusiasts, supplementation with calcium does not prevent skeletal disease; in fact, excessive intake of calcium negatively affects skeletal development and can actually increase a dog’s risk of some forms of skeletal disease. A food with a calcium level that is between 1.0 and 1.5 percent is best. Supplementation with calcium tablets or calcium-containing foods is not necessary and should be avoided.
Feeding Practices for Healthy Development
In addition to selecting an appropriate food, several feeding and care practices are helpful for ensuring your large breed puppy’s healthy development:
• Use portion-controlled feeding: Large breed puppies should be fed two to three pre-measured meals per day. The amount of food should be regularly adjusted in response to your puppy’s weight and body condition. Free-choice feeding is not recommended because even moderate overconsumption will contribute to an accelerated growth rate. The amount to feed can be estimated using the guidelines provided on the food’s package and adjusted to meet your puppy’s daily needs (see Box 2).
• Monitor body weight and body condition: The best way to achieve a healthy rate of growth in your puppy is carefully monitor body weight and to feed to attain a lean and well muscled body condition. Weigh your puppy bi-weekly during the first year of life. Consult your veterinarian if you need help in evaluating proper body condition in your dog.
• Do not feed an adult maintenance food to your large-breed puppy: Some dog enthusiasts suggest feeding an adult maintenance food rather than a growth diet to large and giant breed puppies. This recommendation comes from the mistaken belief that maintenance foods promote a lower rate of growth than growth diets. However, the energy and nutrients of adult maintenance foods are not balanced for the needs of growing dogs. It is best to choose a high quality growth diet that is designed for large breed puppies with an appropriate energy and nutrient density.
• Do not supplement a balanced food with calcium: Dietary calcium supplements or calcium-containing foods should never be added to a balanced, complete food that has been formulated for growing dogs. Excess calcium intake can be detrimental to normal skeletal development and may inhibit the absorption of other essential nutrients, such as zinc.
• Provide regular and moderate exercise: Exercise aids in the achievement of proper energy balance and supports muscle tone and development. Young dogs should be exercised at a level that maintains a lean, well muscled body condition. Daily walking, swimming, or retrieving for 20 to 40 minutes is adequate for most dogs. High impact activities such as repeated jumping, agility training, or prolonged periods of running should be restricted until after your dog has reached maturity.