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ContentsAuthor Profiles....................................................................................5
Conditioning the Performance Dog............................................................6Martin Coffman, DVM
Growing Pains: Successfully Raising the Large Breed Puppy............................12Daniel P. Carey, DVM; Allan J. Lepine, PhD
Nutritional Influences on Skeletal Growth of the Large Breed Puppy..................16Allan J. Lepine, PhD
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Author ProfilesMartin Coffman, DVMThe Iams CompanyDr. Coffman received his DVM in 1970 from Auburn University. He was in private small animal practice for thirty years in Jackson, TN and Grove Hill, AL. He is currently Manager of EnthusiastCommunications for The Iams Company’s Research and Development Division. Dr. Coffman is on the Advisory Panel for Auburn’s Sports Medicine Program. A sporting dog enthusiast, he owns Briarmaster Kennels and is active in Beagle field trials.
Daniel P. Carey, DVMThe Iams CompanyDr. Carey received his BA degree in biology from Illinois Wesleyan University in 1973. He continued graduate studies in biochemistry at the University of Missouri-Columbia where he also received his DVM in 1978. Dr. Carey has been in private and clinical practice, including three years in the United States Air Force as base veterinarian. He joined The Iams Company in 1986 and is currently Director of Technical Communications for the Research and Development Division. Dr. Carey has been directly involved in nutrition research on a wide variety of animals and has experience in clinical, surgical, diagnostic, and nutritional research.
Allan J. Lepine, PhDThe Iams CompanyDr. Lepine received his PhD in nonruminant nutrition from Cornell University in 1987, after which he joined the faculty at The Ohio State University as an Assistant Professor in the Department of Animal Science. In 1993, he accepted a position in Research and Development at The Iams Company where he is currently Principal Research Nutritionist. His research interests include neonatal nutrition, growth, and development as well as the effects of nutrition on reproduction in companion animals. Dr. Lepine has published more than 60 scientific papers and abstracts in peer- reviewed journals.
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NutritionalInfluences onSkeletal Growthof the LargeBreed Puppy
Martin Coffman, DVMResearch and Development DivisionThe Iams Company, Lewisburg, Ohio, USA
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Common sense must prevail during exercise programs. Monitor the dog’s weight and appearance. Think “gradual”. Performance dogs cannot be conditioned from scratch in the two weeks before entering their event.
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Table 1. Vaccination recommendations
VACCINATION RECOMMENDATIONS FORADULT PERFORMANCE DOGS
Vaccinations should be administered in the “off” season to allow time for immune response before exposure at events.
Rabies
DistemperAdenovirusParvoParainfluenza
Bordetella
Lyme
Table 2. Parasite control program
dogs have extraordinary exposure to disease-causing agents at crowded events. Veterinarians are knowledgeable about newer vaccines and their appropriate use in individual breeds. Owners and trainers should ask their veterinarian to outline a long-term comprehensive health care plan incorporating vaccinations, parasite control, skin care, dental care, and periodic hands-on examinations by the doctor to avoid sickness that can sabotage a canine performer’s career.
Exercise Most sporting dog owners think of exercise when conditioning is discussed. Law enforcement dogs and sled dogs must have a solid exercise program if they are to complete their tasks. Agility dogs are athletic by design and get exercise as a requirement for their work. Increasingly, show dogs are being exercised to increase stamina, build muscle tone and definition, and to decrease pent up nervous energy. Exercising the performance dog can take many forms.Sporting dog trainers have long used concentrated
exercise conditioning before field trials or hunting because unconditioned dogs usually only handle one day’s work before faltering. It is not uncommon for field dogs to tire after only two hours work. Well-conditioned dogs will perform for much longer periods. Jogging or walking briskly is fine for humans, but this level of exercise is insufficient for the performance dog. Pulling carts or sleds is effective especially if building muscle mass is desired. “Roading” is popular because it is convenient and easy for the trainer and very effective for the dog. A motorized vehicle like an all-terrain cycle is ideal, but an automobile or even a bicycle will work. Choose a dirt road or soft area. Concrete and asphalt are devastating to pads. Keep in mind that your dog cannot notify you that he or she needs to stop for urination. Do not be guilty of ignoring your dog while roading. Roading, like all new skills, takes some training for the dog. Start slowly and go only about one-half mile. The dog should be loosely attached to the vehicle with enough slack in the leash to insure safety. Build the distance up to three miles per day five days per week and increase speed to allow a loaping gate for the dog.1
For some enthusiasts, a mechanical treadmill may be a better choice. These devices vary in price from $1,000 to about $1,700 depending on size and features. The ideal exercise level is a 10-mph speed at an 11-degree slope. Gradually increase time on the treadmill up to three miles per day.
Avoid hard, heavy pulling in a harness. This kind of conditioning exercise can alter a normal, fluid gait. It has been compared to putting a weight lifter on the tennis court.4 Pulling a light cart is acceptable as is roading off horseback if the pace in fast enough. Swimming is another excellent method of exercising the dog. Some dogs are reluctant to swim or insist on playing in the pool. True conditioning exercise usually occurs on a leash with the trainer directing the dog’s swimming efforts.
PARASITE CONTROL PROGRAM FORADULT PERFORMANCE DOGS
Heartworm prevention administered every 30 days year-roundif mosquitoes are present.
Fenbendazole 10% suspension or granules administered daily for 3 straight days every 60 days year round.
Cestex or Droncit administered if immature tapeworms seenin stool
Annual or triennial boosters administeredby veterinarian
Anuual boosters up to age 7
Annual intranasal booster
Annual booster if there is exposure to ticks
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Mental Preparation Prior to competition, performance dogs should have a standard, rarely-varied routine for several weeks. They should be fed at a certain time with a certain food, exercised at a certain time, and groomed at a certain time. Daily training should occur at the same time each day. Dogs thrive on stability and routine.6
When dogs get “on the circuit” a similar routine should be attempted though it is difficult to duplicate this schedule between events due to rigorous travel requirements. Most owners and handlers underestimate the stress placed on show dogs and other performance dogs. Signs of too much stress for an individual animal are: reluctance to compete, hanging back on the lead, and failing to respond to the handler. Physical signs like dropping coat, whimpering for no reason, or failure to eat can be stress related.6 Some animals can become truly ill and require
veterinary attention due to stress. Maintaining a reasonable routine can prevent many problems. Time spent taking prospects to shows or field trials to acclimate them to crowds and the chaos of a dog event can prepare them for their time in competition. Socialization is especially important in performance dogs coming from very successful kennels. As success increases, kennels tend to grow. As the number of dogs increases, outdoor kennels are built and daily personal interaction becomes less likely. Most show breeders are women and less than 40 percent of breeders have children at home. Many show dogs benefit from purposeful exposure to youngsters and men.7
Exposure to varied stimuli and return to a daily stable routine allow performance dogs to handle stress better. Early mental preparation and socialization is important in conditioning both conformation and field dogs.
NUTRITION Performance dog enthusiasts are very interested in canine nutrition. Their rationale is simple: You can buy the best-bred puppy in North America, send it to the finest trainer in North America, and have it in top physical condition, but if the dog is not fed for maximum performance, it cannot win at the highest level. Modification of nutrition is one of the most convenient steps a competitor can take to improve performance. Yet, there are many misconceptions about the characteristics of the best ration for performance dogs.
For decades, protein has been the component of diet in human and canine athletes that gets the most credit for increased performance.2 There is evidence that protein requirements do increase with exercise. During intense conditioning, athletes pro-duce more protein and they utilize more of this compo-nent. Athletes actually have a larger volume of blood and a higher level of red blood cells during training which reflects increased protein usage.2 Very-low-protein levels increase the chance of injury to per-formance dogs and increas-ing the level of protein decreases the incidence of injury.2
However, it is important in a performance dog ration
that nutritional factors other than protein are at high levels. This insures that protein is not used for energy but reserved for tissue building and replacement. Protein is actually one of the least desirable muscle fuels.2 The body cannot store it and every protein has a job to do in the dog’s body. If we ask our performance dogs to use the protein in their ration for energy, some of these functions can be impaired. This explains the increase in injuries in dogs on low-protein diets. Nutritionists have known for years that the main source of energy for the performance dog must come from fat or carbohydrate. The debate has been which of these two components is most important in increasing
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High-fat dietsbegin to help
the dogsprepare for
the trainingseason weeks
before increasedactivity actually
begins.
performance and endurance. Most of us are familiar with the popular “carbohydrate loading” done by marathon runners prior to a race. A large plate of pasta and bread the day before an endurance run increases the stored carbohydrate (glycogen) in the runner’s muscles and allows for better performance. Many dog trainers have merely transposed the successof carbohydrate loading in humans to the canine athlete. But, the effect in dogs has not been the same. In the early seventies, it was observed that sled dogs fed high-carbohydrate rations actually had poor enduranceand even a stiff gait while racing.2 It was theorized that excess glycogen led to increased lactic acid build up in muscle tissue and decreased the dogs’ performance. He switched the dogs to a high-protein, high-fat diet and performance increased while the stiff gait disappeared. The nutritionist never got to prove his lactic acid theory because the sled dog owners would not let him put their dogs back on the high-carbohydrate ration for research purposes. They were sold on the high-fat food! Continued research showed that dogs actually have a very low requirement for carbohydrate and that, indeed, fat was the preferred fuel for endurance in the performing dog. The question often arises: If carbohydrates help people, why don’t they help canine athletes? The reasons are complex and involve differences in gait, cardiovascular physiology and energy metabolism. Dogs and humans just have differences. Researchers have studied the effect of high-fat diet on dogs in intensive training.2 One of the important facts
discovered was that the high-fat diets begin to help the dogs prepare for the training season weeks before increased activity actually begins. The principle product of fat metabolism used for energy is fatty acids (FA). The level of FA must be high for the performance dog to have extra energy. Long before actual hard work begins, the dogs fed high-fat diets have high levels of FA in their blood stream. This early high FA level is extremely important in performance dogs.
Just like with exercise, trainers should not wait until one week before hunting season or a big show to begin the high-fat ration. Owners of large kennels of hard working dogs are tempted to feed a “normal” less expensive dog food during the off season. They switch to the high-fat food at the last minute before the competitive season begins. A better strategy would be to feed a good ration until eight weeks before performance is required and begin the “performance” ration at that point. Beginning the high-fat product early allows maximum FA in the blood stream weeks before beginning stressful activity.
Table 3. Dietary recommendations
This “primes the metabolic pump” in the dog and gives the animal a head start on other entrants. Of course, if one is feeding a high-fat ration prior to training, monitoring of weight gain and food intake is important.
From a practical standpoint, many enthusiasts want to know just why dogs on high-fat rations perform better. Simply put, dogs fed this type of ration prior to training and competition are better able to utilize oxygen. As they run or work or show, they inhale air and absorb oxygen. If muscles of dogs fed the high-fat ration are examined under the microscope, a large increase in the number mitochondria are found. These little cell “furnaces” are the source of energy for the dog. An increase in the size and number of these tiny cell components allows for increased oxygen utilization, which translates to more energy and increased stamina. In fact, research in different breeds points to the conclusion that a high-fat diet can increase performance and endurance as much as selective breeding.2
Competitors might be tempted to just add fat to the ration currently being fed. There are several disadvantages to this and some safety factors.
Here are the important facts about fat supplementation:• Fatty acid supplements are very unstable without
antioxidant stabilization • Most fatty acid supplements contain high levels of the
wrong type of fatty acid, making it difficult to achieve the correct FA ratio.
• Administration of a pill every day to a kennel of performance dogs is not practical.
• Extra supplements add to kennel costs.• Too much of some FA’s may cause bleeding disorders.4
In a large kennel of sporting dogs or show dogs with a long-term breeding program in place, it is essential that a manageable feeding program be utilized that combines economy with a nutritional plane that allows maximum performance. Competition at most dog events is at an all time high. Regardless of class size, the quality of the animals presented is excellent. As a result, every nuance of
Dietary Recommendations for Performance Dogs
Energy Density 4500 kcal ME/kg or greater
Fat 50 – 60% of calories
Protein 30 – 35% of calories
Carbohydrate 10 – 15% of calories
Total Dietary Fiber 3 – 7% of calories
Fatty Acid Profile: omega-6:omega-3 ratio between 5-10:1
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It is crucialthat you
analyze thefood your dog
is getting toinsure that
an adequate level of calories is being
provided.
preparation must be used for success. Newer research allows the enthusiast to understand the special nutritional requirements of the highly bred performance dog as never before and to provide competitive dogs with the best nutrition ever available. The challenge is to design a feeding program that meets all the needs of the animal: high energy demands, high water turnover, special protein requirements, correct fat adjustments, and overall health.5
Dogs in heavy training often do not want to eat large quantities of food. As opposed to dogs used for sporadic hunting or other part-time work that may have increased appetites, pressured competition dogs may develop a
numbed desire for food. In field trial Beagles, it is not unusual for dogs to decrease food consumption by 50% while being campaigned on a daily basis. The combination of lowered appetite, uncomfortable, unfamiliar hous-ing at events and the daily work of competition can lead to weight loss. They are just too tired to eat. These dogs that become finicky require a highly palatable food to help them maintain an adequate caloric consumption. Food products chosen for the competition dog must taste good enough to entice these reluctant eaters.
The ration should supply adequate nutrition in a compact manner. A 53-pound English Pointer can burn
1,600 kcal of energy in a one-day hunt. To supply this much energy requires a very dense dog food. It is crucial that you analyze the food your dog is getting to insure an adequate level of calories is being provided. The protein requirements of dogs in training and those on the “easy list” do not change. About 35% of total calories should come from a meat protein source. Fresh meat has disadvantages as a supplement. It can spoil making storage a problem and food poisoning a possibility. It contains a
lot of water thus making it a less dense food source. High-quality premium dog foods have meat protein readily available to the animal. The ration should contain enough fat to provide the required energy and in the correct fatty acid ratios. Fiber sources should help maintain good hydration and a functional intestinal tract. A food with a total dietary fiber level of 3–7% of a moderately fermentable fiber does this and allows the performance dog to have quick, clean, healthy bowel movements during work and allowsbetter control of evacuations under stress. Trainers and handlers must be aware of water needs of hard working dogs. Big running dogs can drink 5 liters of water per day. Convenient, portable water
containers should be utilized for frequent watering stops. Consumption should be modest at each stop. In the throes of show or field competition, handlers and owners need a quick, convenient source of maximum nutrition. This allows more time for checking cuts, grooming, and personal rest. The best answer is an extremely high-quality commercial ration in a durable container that, when mixed with water, produces a complete, tasty food for the dog and allows the animal to perform to its genetic and trained potential. Owning, breeding, and training high- quality performance dogs is a labor of love. Seeing great dogs work and gain recognition is gratifying as in few other endeavors. There are no shortcuts to success. Conditioning and nutrition are examples of the need to forego the easy or cheap route. The competition is stiff, the work is hard and the stakes are too high for taking chances. Find the best breeding available. Provide the best training. Then, get your dog in top condition to compete, work, or hunt and feed a high-quality food with the correct levels of fat and protein. Then, you can enjoy the accomplishment and respect you and your performance dog deserve.
A nutrient-dense diet that allows enough energy in a small quantity of food
Protein balanced to the dietary calories
A fat profile that maximizes energy and glycogen repletion while minimizing problems
A fiber source that allows for the healthiest dog
Excellent palatability
Convenient to purchase and easy to prepare
Stable and safe to store while traveling from event to event.
CHARACTERISTICS OF A GOOD FEEDING PROGRAM FOR THE PERFORMANCE KENNEL
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1.2.
3.
4.
REFERENCESMueller, Larry: Speed Train Your Own Bird Dog, Stackpole Books 1990.Reynolds, Arleigh et al: The Effect of Diet on Sled Dog Performance, Oxidative Capacity, Skeletal Muscle Microstructure, and Muscle
Glycogen Metabolism in Proceedings of the 1996 Iams International
Nutrition Symposium, 1996.Whele, Robert G. : Snakefoot: The Making of a Champion; The Country Press; 128-129; 1996.Reinhart, Gregory: Fat for the Performance Dog; Performance Dog
Nutrition Symposium; Colorado State University, April 1995.
Reinhart, Gregory: Practical Recommendations for Feeding Performance Dogs; Performance Dog Nutrition Symposium, Colorado
State University, April 1995.Grossman, Alvin; Every Dog Has His Day, on Internet @ cyberpet.com; 1996.Dunbar, Ian: quoted by Grossman from AKC Gazette, 1990 on
Internet @ cyberpet.com, 1996.
5.
6.
7.
Daniel P. Carey, DVMAllan J. Lepine, PhDResearch and Development DivisionThe Iams Company, Lewisburg, Ohio, USA
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Figure 1 – Representative growth curves of a variety of breeds. Adapted from Current Veterinary Therapy V, 1974. (Reprinted from Lepine AJ, Nutritional management of the large breed puppy. In: Reinhart GA, Carey DP, eds. Recent Advances in Canine and Feline Nutrition,Vol II: 1998 Iams Nutrition Symposium Proceedings. Wilmington, OH: Orange Frazer Press, 1998, p54. Used with permission).
140
120
100
80
60
40
20
00 6 12 18 24 30
130# Great Dane
75# German Shepherd
62# Setter
42# Bulldog
28# Human
23# Cocker
10# Pekingese
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DEVELOPMENTAL BONE DISEASESOsteochondrosis Osteochondrosis is a common cause of lameness in growing large and giant breeds with a high incidence in the Great Dane, Labrador Retriever, Newfoundland, and Rottweiler. Osteochondrosis is the degeneration or breakdown of bone and cartilage of certain joints. It commonly is followed by regeneration or calcification of the tissues of the joint while it attempts to heal. It typically
occurs in growing dogs between 5 and 9 months of age and is often associated with rapid growth. Dogs with osteochondrosis usually present to their veterinarian with pain, lameness, and swelling of the shoulder, elbow, hock, or stifle joints. It is considered a systemic disease and affects more than one or 2 joints at a time although it may show in only one. When the breakdown of the cartilage occurs in some of these joints, occasionally small sections of tissue can break loose inside the joint forming a calcified “joint mouse.” This is more commonly known to breeders then as osteochondrosis dessicans or as “OCD.”
Hypertrophic Osteodystrophy Hypertrophic osteodystrophy is another common cause of lameness of puppies in breeds such as Great Danes, Saint Bernards, Boxers, Dalmatians, Irish Setters, German Shepherds, Labrador Retrievers, Collies, and other rapidly growing large breeds at 3 to 8 months of age. It is a condition characterized by abnormal bone growth of the lower front leg (of the radius or ulna – the area just above the carpus). This results in large “wrists” and, sometimes, bowed legs. These puppies may also have an elevated body temperature and/or become anorexic or not interested in eating their food.
Hip Dysplasia Of all the skeletal diseases of dogs, hip dysplasia is the most well known. It is a developmental disease of the hip joint where luxation of the femur from the socket (acetabulum) of the pelvis causes remodeling of this joint. The acetabulum becomes shallow with flattening of the head of the femur. The mismatch of the ball and socket leads to arthritis. Early cases of hip dysplasia may have signs of mild discomfort after exercise or a general mild lameness. As the condition progresses, lameness, pain, abnormal gait, reluctance to rise and a thinning of muscling of the thighs may occur. Hip dysplasia is a polygenic disease (involves many genes) that can be influenced by diet. Rapid growth or rapid weight gain can aggravate the lameness of hip dysplasia.
Panosteitis Panosteitis is another commonly discussed bone disease in the breeder arena. This condition is also known as eosinophilic panosteitis, “Pano” or “Eo Pan”, which is the most common terminology used by breeders. It is a disease of the long bones of the forelimb such as the humerus, radius or of the hind leg including the femur or tibia of large and giant breeds of dogs. German Shepherds seem to have a higher incidence of this condition. However, any breed can be plagued by this condition especially puppies with extremely large bone. Although this condition can cause extreme lameness and be alarming to the average breed or owner, it is self-limiting, and there is no permanent damage or aftermath of the condition. It is most often seen during growth spurts with affected pups usually losing their appetite in addition to showing lameness.
N O R M A L A B N O R M A L
N O R M A L A B N O R M A L
N O R M A L A B N O R M A L
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Most commonly puppies will have acute onset of lameness with no history of trauma. Male puppies are 4 times more affected than females.1 Puppies with panosteitis will often “carry” or favor the limb that is affected for just a few days or many weeks. Often, the puppy will appear to have a “shifting leg lameness,” that is, they appear to be lame on one leg one day and another leg the next. Such puppies usually have panosteitis of multiple bones and limp on the one that hurts the most. What influences the developmental bone diseases? Where does diet fit in? What can be done to avoid these problems in puppies? It is known that all skeletal development is affected by four major areas:
GENETICS As we all know, “the genes make the dog.” Therefore genetics can play a significant role in the development of certain bone diseases. Puppies from very large boned parents may have large bones and be more apt to develop panosteitis. Puppies from dysplastic parents are much more likely of becoming dysplastic. Puppies from parents who were rapidly growing are more likely to grow rapidly, too. When considering genetics and nutrition together, there are 2 well-known nutritional truths. The first is that growth rate and adult size are programmed in the genes for every puppy. The second is that increasing the energy intake (supplying more calories) to a puppy can push the growth rate to its upper limit and thus increase the likelihood of certain skeletal diseases. This leads to the next topic of discussion– nutrition.
NUTRITION Nutrition can influence the development of certain developmental bone diseases in 3 areas: protein content of a diet, energy content or calories fed, and calcium intake (whether as part of the diet or as a supplement).
Dietary Protein In the past, some diets were said to be “too hot” (ie, contained high levels of dietary protein) and promoted rapid growth rate predisposing large and giant breed dogs to skeletal problems. However, controlled research done in 1991 by Nap et al.,2 showed that protein was uninvolved. Great Dane puppies were fed identical diets except for the protein content from weaning for 18 weeks. These diets had a broad range of dietary protein compositions of 31.6%, 23.1% and 14.6%. This research demonstrated that skeletal development problems were NOT related to variations of the dietary protein content. Thus, protein in and of itself does not effect bone development or influence the incidence of developmental bone diseases.2,3 (The low-protein diet did have some problems keeping weight on the pups.)
Energy Density However, research done by Hedhammer did find a nutritional factor that does influence the incidence of certain developmental bone diseases. This researcher investigated the issue of dietary energy intake (how many calories a puppy ate each day) by feeding either (1) as much as the puppy wanted toeat [ad libitum] or (2) a restricted amount of food [66% of the ad libitum amount]. This research was also done on Great Dane puppies which were fed until the puppies were 60 weeks ofage (approximately 15 months old). He found that the puppiesfed as much as they wanted (ad libitum) had a significantly higher incidence of skeletal abnormalities than those puppies who were fed a restricted amount of food (meal fed).4
Another researcher (Dammrich) in 1991 confirmed this fact by doing research on Great Dane puppies fed ad libitum or a restricted diet of 70-80% of the ad libitum fed puppies.5 His research was done from weaning until 6 months of age. He proved that puppies fed as much as they wanted had weaker bone and inadequate support of the joint cartilage. Thus, those puppies fed as much as they wanted had a significantly higher frequency of developmental bone diseases.5
Iams research has also shown that the number of dogs showing the radiographic changes of osteochondrosis and HOD increases as the number of calories consumed increases. In other words, pups that get too many calories grow fast and are more likely to have developmental bone problems.
Calcium The amount of calcium in a diet has also been demonstrated to have significant effects on the development of the skeleton of the large or giant breed puppy. Research done by Hazewinkel et al. showed that diets too high in calcium have been shown to have detrimental effects on puppies’ endocrine systems, blood levels of calcium and skeletal development and will increase the risk of developmental bone diseases. Specifically, high levels of calcium affected bone development by causing retained cartilage cones, increased bone mineral, and delayed bone remodeling. These puppies had more abnormalities seen on their radiographs (x-rays) with more osteochondritic lesions (osteochondrosis).6,7
Another research project done by The Iams Company evaluated 3 diets containing 26% protein and 14% fat, but differing in the calcium and phosphorus levels:
Great Danes puppies were fed the various diets from pre-weaning until 18 months of age. During this research growth rate, body composition, bone mineral density or composition, and skeletal integrity were evaluated. This research demonstrated that diets with 0.8% calcium and 0.67% phosphorus level provided ideal mineral levels for
Test Diet Ca:P Levels
1 2.70% calcium to 2.20% phosphorus
2 0.80% calcium to 0.67% phosphorus
3 0.48% calcium to 0.40% phosphorus
1 2 3 4Genetics Nutrition Environment Trauma
healthy bone growth and development for large breed dogs. Puppies fed the diet with these levels had better conformational or skeletal structure. These puppies also had a lower prevalence of developmental bone disease or clinical signs of lameness.8-11
Environment Environment also can influence the incidence of certain types of developmental bone diseases occuring in our large breed dogs. Environmental influences are anything that can effect an animal from non-genetic sources. Space for exercise and exercise (or lack of) and conditioning are considered environmental influences. Dogs that are not exercised properly do not develop adequate muscling or tendon strength, and thus these things can alter bone density and development. Slippery floors or awkward footing can lead to abnormal gait and altered bone development, particularly in very young puppies.
Trauma Any type of trauma, especially to the rapidly growing large or giant breed dog can effect both bone and joint development. Broken bones, slipped growth plates, or injured joint cartilage can all be factors that determine whether dogs can be predisposed to developing bone or joint problems in the future. Thus it is important to allow for proper exercise and conditioning of large breed dogs, but not to stress their delicate, young skeletons which may cause injury that could be permanent. Puppies should not be pushed to perform. A puppy with an otherwise unnoticeable osteochondrosis often has a history of running and pulling up lame. The combination of a developmental bone disease and trauma created the lameness. Surfaces and conditions should be carefully evaluated to avoid dangerous structures for dogs. Trauma-related injury can be avoided by using common sense and light exercise.
Practical Implications Large and giant breed dogs can be plagued by the occurrence of certain bone diseases during their early and adolescent growth stages. Genetics, environment, and nutrition can influence the development of these conditions. Based on recent research, nutrition can play a key role in decreasing the occurrence and severity of these diseases. Some of the concepts we know now exist are:
Managed growth rate is important in reducing the incidence of skeletal disease•Rapid rate of growth
contributes to the incidence of skeletal abnormalities. Feed a diet with around 15% fat to provide enough calories for growth but not so much as to fuel rapid growth.
•Dietary protein has little impact on skeletal disease. Feed a diet with about 26% protein to support muscle development.
•Mature size is genetically programmed.
Support healthy bone development•Appropriate dietary calcium and phosphorus
concentrations are essential. The diet should have a calcium level of 0.8 to 0.9% and be balanced with phosphorus.
•Calcium supplementation or high calcium diets can increase the incidences of certain developmental bone diseases. Any supplementation whether as calcium, bone meal or dairy products will increase the calcium intake and increase the puppy's likelihood of developmental bone disease.
Breeders CAN influence the frequency of certain bone diseases occurring in their kennel by implementing proper feeding management of their puppies, considering the genetic potential of the heritage of their dogs, exercising and conditioning properly, as well as preventing trauma or damage to growing bones and cartilage of their puppies.
REFERENCESBarrett RB, Schall WD, Lewis RE: Clinical and radiographic features of canine eosinophilic panosteitis. J Am Anim Hosp Assoc 1968; 4:94-104. Nap RC, Hazewinkel HAW, Voorhout G, Van De Brom WE, Goedegebuure SA, Van'T Klooser ATh. Growth and skeletal development in Great Dane pups fed different levels of protein intake. J Nutr 1991; 121:S107-S113.Nap RC, Hazelwinkel HAW, Voorhout G, Biewenga WJ, Koeman JP, Goedegebuure SA, Van't Klooser ATh. The influence of dietary protein content on growth in giant breed dogs. J Vet Comp Orth Traumatolo 1993; 1-8. Hedhammer A, Wu F, Krook L, Schryver HF, Delahunta A, Whalen JP, Kallfelz FA, Numez EA, Hintz HF, Sheffy, Ryan GD. Overnutrition and skeletal disease. An experimental study in Great Dane dogs. Cornell Vet 1974; 64 (suppl. 1): 1-160.Dammrich K. Relationship between nutrition and bone growth in large and giant dogs. J Nutr 1991; 121(11 Suppl):S114-21Hazelwinkel HAW, Goedegebuure SA, Poulos PW, Wolvekamp WThC. Influences of chronic calcium excess on the skeletal development of growing Great Danes. JAAHA 1985; 21:377-391Goedegebuure SA, Hazewinkel HAW. Morphological findings in young dogs chronically fed a diet containing excess calcium. Vet Pathol 1986; 23:594-605.Lauten SD, Brawner Jr WR, Goodman SA, Lepine AJ, Reinhart GA, Baker HJ. Dual energy x-ray absorptiometry measurement of body composition and skeletal development in giant breed dogs fed diets differing in calcium and phosphorus. FASEB J 1997; A388.Lauten SD, Brawner Jr WR, Goodman SA, Lepine AJ, Reinhart GA, Vaughn DM, Baker HJ. Body composition of growing Great Dane puppies fed diets varying in calcium and phosphorus concentrations evaluated by dual energy x-ray absorptiometry. ACVR 1996; 1-8.Brawner Jr WR, Hathcock JT, Goodman SA, Lauten SD, Cox NR, Kincaid SA, Baker HJ, Lepine AJ. Radiographic lesions observed in growing Great Dane puppies fed diets varying in mineral content: a preliminary report. ACVR 1996; 1-9.Goodman SA, Montgomery RD, Lauten SD, Hathcock JT, Brawner Jr WR, Cox NR, Kincaid SA, Reinhart GA, Lepine AJ, Baker HJ. Orthopedic observations in Great Dane puppies fed diets varying in calcium and phosphorus content: a preliminary report. Veterinary Orthopedic Society 24th Annual Conference Proceedings; 1997; 51.
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The ideal diet for growinglarge breed puppies
from weaning toadulthood contains
26% protein15% fat
0.80% calcium0.67% phosphorus
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NutritionalInfluences onSkeletal Growthof the LargeBreed PuppyAllan J. Lepine, PhDResearch and Development DivisionThe Iams Company, Lewisburg, Ohio
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Three dietarycomponents–the dietaryconcentrationof energy,protein, andcalcium (andphosphorus)–have beenimplicated as primarycontributors toan increasedincidence ofskeletal diseasein the growinglarge breedpuppy.
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development, morphology, and pathology of the skeleton in the large-breed puppy. Hazewinkel and colleagues5 and Goedegebuure and Hazewinkel6 evaluated the effect of feeding either a typical calcium diet (1.10% Ca/0.90% P) or a high-calcium diet (3.30% Ca/0.90% P) to Great Dane puppies from weaning through 6 months of age. The effect of the high-calcium diet on endocrine status (hypercalcemia, hypophosphatemia, less active parathyroid glands, increased activity of thyroid C cells), skeletal development (increased osteoblasts, decreased osteoclasts, decreased osteoclast activity, more retained cartilage cones, increased bone mineral mass, delayed bone remodeling), and skeletal disease (increased radiographic irregularities, more osteochondritic lesions) clearly demonstrated the negative impact of excess dietary calcium on skeletal health of the large-breed puppy. This conclusion was further supported by the finding that the large-breed puppy was ineffective in reducing intestinal calcium absorption when provided a high-calcium diet and was therefore unable to protect itself from a chronic high dietary calcium intake.7 In contrast, intestinal calcium absorption was increased to greater than 90% of calcium intake when a low-calcium diet was consumed.
CURRENT RESEARCH Research published to date clearly documents that (1) maximal growth rate supported by elevated energy intake increases the incidence of skeletal disease, (2) dietary protein level has little influence on the incidence of skeletal disease, and (3) high dietary calcium concentration interferes with normal skeletal development and promotes skeletal pathology in the large-breed puppy. Nevertheless, data on which to base specific dietary recommendations for dietary energy and calcium concentrations for the large-breed puppy are lacking. A comprehensive research effort is underway to provide this essential information. In brief, a total of 36 Great Dane puppies were assigned to three treatment diets differing in calcium and phosphorus concentration: 0.48% Ca/0.40% P (LC), 0.80% Ca/0.67% P (MC), and 2.70% Ca/2.20% P (HC). These levels of calcium and phosphorus were selected to allow evaluation of the hypothesis that a calcium and phosphorus concentration lower than found in typical premium puppy diets (e.g., 1.20% Ca/1.00% P) would enhance skeletal health when provided in a dietary matrix of reduced energy density designed to manage growth rate and decrease the slope of the growth curve. To achieve the reduced energy density, all diets were formulated to contain 14% fat, compared to 20% to 21% fat in the typical premium puppy food. Dietary protein concentration was also lowered to 26% to maintain an appropriate dietary protein:energy ratio. The three diets were fed to growing Great Danes from preweaning through 18 months of age. Briefly reported here are the results published to date for body weight, body composition, bone mineral density, and skeletal integrity (based on radiographic and orthopedic examinations).
Puppies consuming the MC diet grew more rapidly and had increased body weights relative to puppies fed the HC and LC diets (Figure 1).8 Nevertheless, no differences in bone lengths were apparent across treatment groups by 6 months of age. Lean body mass and fat tissue were equal across treatments at weaning, but by 4 months of age, puppies fed the MC diet had a higher percentage of fat tissue and lower lean body mass as compared to the other two treatment diets.9 Differences in bone mineral content (BMC), as measured by dual energy x-ray absorptiometry (DEXA), were evident by 8 weeks of age and continued to
Figure 1 – Relative body size of Great Danes consuming a diet con-taining either high calcium (HC; top), medium calcium (MC; middle) or low calcium (LC; bottom).
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The resultsof ongoing research clearlydocument thatthe uniquenutritionaldemands of thelarge breedpuppy are best provided by a dietary matrixcontaining 26% protein, 14% fat, 0.80% calcium,and 0.67%phosphorus.
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diverge through 6 months of age.9 BMC, as a percentage of body weight, was 1.07% (LC), 1.42% (MC), and 1.85% (HC) at 2 months of age and increased to 2.91% (LC), 3.45% (MC), and 3.84% (HC) by 6 months of age (Figure 2). Furthermore, bone mineral density (BMD) values were likewise different by 8 weeks of age: 0.442 g/cm2 (LC), 0.456 g/cm2 (MC), and 0.482 g/cm2 (HC; Figure 3).10 Differences in BMD across treatment groups continued through 6 months of age, after which time the magnitude of the response began to decrease. By 12 months of age, BMD values were 0.976 g/cm2 (LC), 1.046 g/cm2 (MC), and 1.054 g/cm2 (HC).10 Orthopedic examination revealed that 6 of the 15 dogs consuming the HC diet exhibited clinical signs of lameness through the first 6 months of the study.11 Three of these dogs exhibited clinical signs of hypertrophic osteodystrophy. Conformation of dogs fed the high mineral diet was considered inferior to those receiving the other diets.
PRACTICAL IMPLICATIONS The results of this ongoing research clearly document that the unique nutritional demands of the large-breed puppy are best provided by a dietary matrix containing 26% protein (high quality, animal-based source), 14% fat, 0.80% calcium, and 0.67% phosphorus. Support for this recommendation is based on the following research observations:
• A reduced dietary energy density, which is typically found in puppy foods, provides for easier management of growth rate and will moderately restrict the growth rate relative to the genetic potential. Mature body size is genetically determined and will simply be attained at a slightly older age with a more gradual growth rate.
•The altered body composition of puppies fed the MC diet may reflect that 0.80% calcium is a more appropriate level of supplementation, supporting the modestly restricted growth velocity resulting from a lower energy density. Puppies fed the MC diet may therefore be placed on a relatively more advanced position on the growth curve compared to puppies fed the HC and LC diets, while maintaining a more gradual growth curve relative to the genetic potential.
• BMC and BMD were lower in puppies fed the LC diet (0.48% calcium), indicating an inadequate level of supplementation in this dietary matrix. Furthermore, BMC and BMD responses occurred very early in the growth phase, indicating the need to address the nutritional requirements of the large-breed puppy immediately after weaning.
• Orthopedic examination revealed a higher incidence of abnormalities in the puppies consuming the HC diet (2.70% calcium), indicative of calcium oversupplementation in this dietary matrix containing a reduced energy density.
Figure 2 – Percentage of bone mineral content of Great Danes consuming a diet containing high calcium (HC), medium calcium (MC), or low calcium (LC).
Figure 3 – Percentage of bone mineral content of Great Danes consuming a diet containing high calcium (HC), medium calcium (MC), or low calcium (LC).
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REFERENCESAmerican Kennel Club: The Complete Dog Book: Official Publication of the American Kennel Club 1992; ed 18. New York, Macmillan.Hedhammer A, Wu F, Krook L, et al: Overnutrition and skeletal disease. An experimental study in Great Dane dogs. Cornell Vet 1974; 64(Suppl 1):1–160. Dammrich K: Relationship between nutrition and bone growth in large and giant dogs. J Nutr 1991; 121:S114–S121. Nap RC, Hazewinkel HAW, Voorhout G, et al: Growth and skeletal development in Great Dane pups fed different levels of protein intake. J Nutr 1991; 121:S107–S113.Hazewinkel HAW, Goedegebuure SA, Poulos PW, Wolvekamp WThC: Influences of chronic calcium excess on the skeletal development of growing Great Danes. JAVMA 1985; 21:377–391.Goedegebuure SA, Hazewinkel HAW: Morphological findings in young dogs chronically fed a diet containing excess calcium. Vet Pathol 1986; 23:594–605.Hazewinkel HAW, Van Den Brom WE, Van ‘T Klooster ATh, et al: Calcium metabolism in Great Dane dogs fed diets with various calcium and phosphorus levels. J Nutr 1991; 121:S99–S106.
Goodman SA, Montgomery RD, Lauten SD, et al: Orthopedic observations in Great Dane puppies fed diets varying in calcium and phosphorus content—A preliminary report. Vet Comp Orthopaed Trauma 1997; 10:75.Lauten SD, Brawner WR, Goodman SA, et al: Changes in body composition of growing Great Danes fed diets varying in Ca and P level evaluated by dual energy x-ray absorptiometry. ACVR Proceedings 1996; 1-8, (Abstract).Lauten SD, Brawner WR, Goodman SA, et al: Dual energy x-ray absorptiometry measurement of body composition and skeletal development in giant breed dogs fed diets differing in calcium and phosphorus. FASEB J 1997; 11:A388.Brawner WR, Hathcock JT, Goodman SA, et al: Clinical and radiographic observations of growing Great Danes fed diets varying in mineral content: A preliminary report. ACVR Proceedings, 1996; 1-9 (Abstract).
