Canine nutrition - What do dogs need?What do dogs need? Proteins Proteins are the building blocks of the body. They are made up from two different types of amino acids, and dogs can manufacture some in their bodies and others must be supplied in their food. These amino acids are called essential and non-essential.
Essential amino
acids include: arginine, histidine, isoleucine, leucine, lysine, methionine,
Essential amino acids come from the dog's diet because they are unable to make those. Non-essential amino acids can be made within the body. Proteins that the dog eats, such chicken or beef, are broken down within the body by enzymes. They then reform as proteins that are of use to the dog, for example, they may form muscles, hair, skin and antibodies. The amount of protein required depends on the life stage or lifestyle of the dog, i.e. growth, pregnancy or if the animal is working. Proteins from animal sources -- meat and meat byproducts -- are more complete and easier to extract and digest than proteins from plant sources. Proteins form the enzymes that metabolize food into energy as well as the hormones that guide various body functions. They can also be metabolized to provide energy. High protein feeds are recommended for puppies and working dogs, but too much protein can cause renal (kidney) disease and has been implicated in some temperament problems. A dog's protein requirement depends upon the life stage and activity of the dog. Generally, puppies need more dietary protein than do adult dogs. Caloric requirements are also high during growth phases, and protein needs of a puppy can be met by a high quality protein providing 20 to 25% of dietary calories. Research has shown that the minimum protein requirement for geriatric dogs is about 50% greater than for younger adult dogs. However, diets formulated for adult maintenance usually provide adequate protein. Research has shown that the healthy geriatric dog utilizes protein in a manner similar to the young adult dog. Severe protein deficiency in dogs results in poor food intake, growth retardation or weight loss, subnormal concentrations of blood proteins, muscle wasting, emaciation and death. Less severe deficiency can cause a rough, dull coat, compromised function of the immune system and poor milk production in reproducing bitches. Animals maintained with inadequate protein reserves may appear healthy, but are most susceptible to stresses, including increased susceptibility to infections as well as the effects of toxic compounds or cancer-causing agents. Weight-reduction (or low-calorie) diets formulated for sedentary dogs are lower in fat and calories and may have a lower protein level. These diets may also contain a higher percentage of crude fiber. A dog food designed for weight reduction is not appropriate for young growing puppies, or during pregnancy or nursing. Carbohydrates Carbohydrates should make up about 40% to 55% of a balanced dry food diet for dogs. They include sugars, starches and dietary fiber. The primary function of carbohydrates is to provide energy. Basically, carbohydrates are supplied in the diet by cereal grains and simple sugars, such as glucose, sucrose (table sugar), and lactose (milk sugar). Carbohydrates are digested by enzymes in the small intestine or the gut. Most of the carbohydrates in dog food diets are broken down and absorbed as glucose or other simple sugars before being used for energy. Dietary fibers are carbohydrates that are not completely digestible. When animals consume diets containing more carbohydrates than are needed, the excess energy is stored in the form of glycogen in the liver and muscles and is converted to fat. During periods of fasting, stress, or exercise, glycogen is broken down to glucose and delivered to the bloodstream to provide needed energy. A large portion of the carbohydrates in pet foods is derived from cereal grains. Cereal grains are usually processed by grinding, flaking or cooking. These processes improve palatability and digestibility. Here is a list of typical sources of carbohydrates found in dog foods: Cereal Grain Fiber is a general term used to describe complex carbohydrates which are not digested by enzymes in the small intestine of dogs. Some fibers can be partially degraded by normal microflora in the large intestine. Dietary fiber has many effects within the gastrointestinal tract. Some fibers swell with water or have a high water-holding capacity. A high or low water-holding capacity can change the speed with which food passes through the intestinal tract. The increased bulk of high-fiber foods contributes to stomach distention and causes a dog to eat fewer calories. Fiber influences the rate of passage of food through the intestine by slowing stomach emptying, but the specific effects vary with the type of fiber, how it is processed, and the amount fed. Generally speaking, fiber has a normalizing effect on the rate of passage of food through the intestine, slowing the rate in animals with diarrhea and increasing it in constipation. Dietary fiber also slows or decreases digestion and absorption of nutrients, including fat, vitamins and minerals. As a protective mechanism, fiber can bind to some toxins and prevent their absorption into the bloodstream. Excessive dietary fiber is associated with adverse effects such as the production of loose stools, flatulence, increased stool volume and frequency, and decreased dietary caloric density.
Fats are essential for good health and play an important role in dog food. Several of the benefits for your dog include: keep their skin and coat healthy, allergy and inflammation control, improve immune function and blood clotting, reproductive efficiency, and kidney function In proper moderation, fats give your dog energy needed to run jump and play, and they and keeps him cool when it's warm and warm when it's cool. They also contribute to the way a food tastes, so your dog will enjoy it. Dietary fats are caloric dense ingredients that provide an important source of essential fatty acids and fat soluble vitamins (A, D, E, and K). Puppies need dietary fat and cholesterol for growth and to maintain proper health. Adult dogs require essential fatty acids in the diet to sustain metabolic and physiologic functions. Fats are commonly composed of three fatty acids attached to a glycerol skeleton resulting in the name triglycerides. The fatty acids that must be supplied in the diet of dogs are called essential fatty acids. A diet high in too much fat will contribute to obesity in a sedentary dog, because fats have more calories than protein or carbohydrates. Vitamins and Minerals - Supplements Dog foods also must contain vitamin and mineral supplements in concentrations that provide balanced proportions of vitamins and minerals - too much of one vitamin or mineral may interfere with the absorption of another vitamin or mineral use. Vitamins and minerals are necessary for proper absorption of fats and carbohydrates and for the chemical reactions in the body. Not only do organisms need these nutrients, but they need them in proper amounts and ratios for optimum health. For example, unless calcium and phosphorus are in balance, neither will be properly absorbed or utilized, which can lead to bone or muscle problems. Some dogs may need vitamin or mineral supplements at some time during their lives when recovering from illness or injury, and during pregnancy, or stress. Always ask your veterinarian for his advice regarding supplements. Vitamins Vitamins are divided into fat-soluble and water-soluble types. Fat-soluble vitamins are stored in fatty tissue. Fat-soluble vitamins are A, D, E, and K. They are involved in several body functions, including eyesight, bone formation and strength (with calcium), cell stability, and blood coagulation. Water-soluble vitamins are the B-complex, C (ascorbic acid). Water-soluble vitamins are excreted from the body if they are not used through sweat, urine and feces. Let's start with the 4 fat-soluble vitamins: A, D, E, and K First of all, fat soluble vitamins can build up in tissues and become toxic. For example, excess Vitamin A can lead to bone disease, too much Vitamin D can cause calcification of soft tissue, lungs, and kidneys and the toxicity in Vitamin E overdose is being studied to determine the extent on adverse effects on blood coagulation and thyroid function.
Vitamin A deficiency can cause several eye problems; including dryness, corneal ulcerations, and inflammation of the conjunctiva, but clinical cases of vitamin A deficiency in dogs are uncommon. This is probably because they are able to consume sufficient quantities of the vitamin from commercial diets. In addition, dogs are able to store vitamin A in the liver and use these reserves during periods of inadequate consumption such as a debilitating disease. Commercial dog foods provide adequate amounts of vitamin A in dog food products so that supplementation is not necessary. Over supplementation of vitamin A could cause toxicity in animals, and result in deformed bones, weight loss, anorexia, and even death. Toxicity occurs when a chronic excessive intake exceeds the liver capacity to store the vitamin, or when large short-term doses exceed the liver's ability to remove the vitamin from an animal's circulation. Vitamin D Vitamin D deficiency causes rickets - a deficiency disease that affects puppies during the period of skeletal growth. It's characterized by soft and deformed bones, and is caused by failure to assimilate and use calcium and phosphorus normally due to inadequate sunlight or vitamin D. Vitamin E Some tocopherols are more active in the body as nutrients than others. The alpha form of the vitamin is the most active as a nutrient, and it is the compound added to pet food to meet the animal's dietary requirement. When vitamin E is used as a preservative, a mixture of several forms of tocopherol is added to prevent oxidation of the fat in the diet, but is not considered part of the nutrient content of the diet. There is no known toxicity due to oral ingestion of vitamin E in animals. Good quality commercial pet foods contain adequate amounts of this vitamin to meet an animal's dietary needs. Deficiencies of Vitamin E can cause muscle tissue breakdown, reproductive failure, and impairment of immune response.
Vitamin K Commercial dog foods provide adequate amounts of vitamin K in dog food products so that supplementation is not necessary. Vitamin K can be synthesized by bacteria in the dog's intestine and does not need to be added to the diet under ordinary circumstances.
B-Complex Vitamins
are:
A deficiency state could occur for one or more of the B-complex vitamins in animals fed homemade diets that are not properly formulated or balanced. Vitamin C (Ascorbic
Acid) Some individuals believe that dogs manufacture their own vitamin C in sufficient quantities to meet individual requirements and supplementation isn't necessary. However, vitamin C synthesis in dogs may be inadequate on a low protein diet and a dog may not be able to synthesize the vitamin and so require it in the diet. In addition, some dogs under stressful conditions may not make enough. Vitamin C synthesis also declines as a dog ages. Stress, degenerative diseases, infections and inflammation rapidly deplete vitamin C levels. Joint function also increases vitamin C requirements. This vitamin is also a water-soluble vitamin and has a primary metabolic role in the body involving the production of collagen. Some people believe that Vitamin C helps prevent injuries, fights stresses, and assists in the prevention of hip dysplasia and arthritis. Vitamin C is needed for good bone development and the strengthening of surrounding ligaments. If you and your vet decide that vitamin C is warranted, begin by adding the supplement slowly. Gradually increase the dosage. Sudden increases in Vitamin C may result in diarrhea. Always check with your veterinarian for his recommendations!
Minerals are usually grouped into macro (major) and micro (trace) categories. Macro-minerals are needed in greater amounts in the diet, and are found in larger amounts in the body than micro-minerals. They all are essential for bone formation, muscle metabolism, fluid balance, and nervous system function. Macro-minerals nutrients, for which the dietary requirement is expressed in grams, including calcium, phosphorus, magnesium, sodium, potassium, and chloride. Calcium and phosphorus are necessary in a specific ratio for bone formation and strength. An imbalance in the ratio will cause bone problems. All dog foods available today have more than enough calcium for a large or giant breed, so supplementation with this mineral is not needed. Magnesium is found in soft tissue and bone; it interacts with calcium to provide proper heart, muscle, and nervous tissue function and aids in metabolism of potassium and sodium. Deficiency leads to muscle weakness and sometimes convulsions. Sodium is found
in fluids outside the tissue cells and performs a function similar to Potassium is found within tissue cells and is important in cellular activity. A deficiency causes muscle weakness and heart and kidney lesions.
Generally speaking, trace minerals are necessary not only in the production of red blood cells, but also in oxygen transport, skin pigmentation and preservation, the functioning of enzymatic systems, the synthesis of thyroid hormones, etc. Each trace mineral fulfills one or more roles in a number of bodily functions. Iron is critical for healthy red blood cells and an essential component of some enzymes. Iron from animal sources appears to be more readily absorbed than that from vegetable sources. Copper is necessary in production of melanin, the pigment that colors coat and skin, and is linked with iron metabolism. Deficiencies can cause a bone disorder and anemia even if iron intake is normal. Zinc is heavily involved in skin and coat health, enzyme function, and protein synthesis. Deficiencies lead to poor growth, anorexia, testicular atrophy, and skin lesions. Little is known
about the need for manganese and selenium in the dog, but they are Water Healthy water intake is extremely important - it can be a matter of life and death. A living beings
need water and water is more important than food! Because water is involved in practically every reaction within a dog's body, any large deviation will be associated with adverse effects. An animal's body, therefore, has several systems designed to maintain constant water balance. Dogs acquire water mainly by drinking water. They also get water from the water content of food, and as a by-product from metabolism of carbohydrates, proteins and fats the dog eats. Keeping your dog sufficiently hydrated is very important. Dogs can be thirsty anytime so you should leave water out for your dog all the time and keep the water bowl clean. Water is excreted in large volumes during high levels of energy and activity. Great amounts of water are depleted through respiration, salivation, urination and transfer of heat dissipated by the tongue. This loss of water can also vary depending on the temperature. It is imperative to compensate water depletion with readily available water. Water is lost in urine, feces, respiration, and to a small extent in flakes of skin, saliva, and nasal secretions. For nursing females, water will also be required for milk production. The bottom line regarding water: Always remember, if you believe you have a watering problem, please see your vet immediately. A delay can be a matter of life and death. Never allow a dog to drink heavy amounts of water before, during, or immediately after exercise. During warm weather,
your pets will drink more water than during cold weather. Try to The water should always be kept clean, cool and fresh. If you and your dog are swimming in the ocean, be sure to bring drinking water along, because it is not healthy for your dog to drink salty water. Without sufficient water intake, your dogs' bodily functions can shut down. On the other side of the coin: Too much water (excessive drinking) may be an indication of problems as well. Most of these problems
are minor such as more salt intake than normal, a lot of exercise, and temporary
stressful conditions. These conditions generally will quickly correct themselves
or can be handled by diet and common sense. A dog may be dehydrated even when drinking plenty of water. There are two simple ways to determine dehydration. 1. On the upper back just below the shoulders, using your thumb and forefinger, pinch the skin gently, lift up and then let go. If the skin snaps back easily, your dog is absorbing enough water. 2. Run your thumb or index finger along the gum line. If the gum line is wet and slippery, then your dog is OK. If either of these tests fails, let your pet keep drinking and call the vet immediately. Lastly, puppies
are easily over-watered and can this can hamper housebreaking. Changing Diets and Supplementation If you decide to switch dog foods, do it slowly over a seven to ten day period. Gradually add more of the new food, while reducing the amount of your previous food, until you are feeding only the new diet. This slow transition will help avoid any digestive upset, and will not be noticeable to your dog if he's a finicky eater.
The Bottom Line: As long as you feed your dog a complete and balanced diet, there is no need to supplement with vitamins or minerals unless recommended by your veterinarian. Back
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