Nutritional Physiology of Rabbits PDF

Nutritional Physiology of Rabbits-Significance of Energy, Carbohydrates, Lipids, Proteins, Amino acids, Minerals and Vitamins in the Diets of Rabbits Animal Nutrition PVNR TVU ...

Nutritional Physiology of Rabbits-Significance of Energy, Carbohydrates, Lipids, Proteins, Amino acids, Minerals and Vitamins in the Diets of Rabbits Animal Nutrition PVNR TVU  - Nutritional Physiology of rabbits Rabbit are monogastric herbivores with an enlarged caecum and colon (hindgut). Animal Nutrition PVNRTVU The nutrients that are undigested in the small intestine reach the cecum where they are fermented by the microorganisms. Rabbits are hind gut fermenters. Rabbit diets comprised of both roughages and concentrates. Rabbits have high level of feed intake and rapid transit of feed through digestive tract.  - Digestive System of Rabbits Animal Nutrition PVNRTVU  - Digestive Physiology of Rabbits The functioning of rabbit’s upper digestive tract is almost similar to other monogastric mammals The speciality of rabbit digestive system functioning is in the hindgut and Animal Nutrition PVNRTVU especially the dual function of proximate colon When the caecum digesta enter proximate colon, most of liquid fraction (soluble products and small particles (0.3 mm long) mainly of lignin and cellulose moved through colon by peristaltic action and excreted as Hard faeces. This particular functioning of colon requires roughages (Indigestible fibre) and to maintain intestinal health  - Digestive Physiology of rabbits Animal Nutrition PVNRTVU  - Caecotrophy in Rabbits Rabbits produce two types of faeces: hard and soft (caecotrophes) Animal Nutrition PVNRTVU Hard faeces mainly composed of large particles consisting of lignin and cellulose Soft faeces mainly contain small particles with B-complex vitamins, bacterial protein and small amounts of volatile fatty acids. The behaviour of ingestion of soft faeces directly from the anus is called caecotrophy Caecotrophy provide most of the B-complex vitamins and some bacterial protein to the rabbit. Caecotrophy is practiced in domestic rabbits as young as 3 weeks of age  - Nutrient Composition of Hard and Soft Faeces Nutrient Hard Faeces Soft Faeces Animal Nutrition PVNRTVU Dry matter(%) 47 34 Crude protein (%) 17 30 Crude fibre (%) 30 18  - Digestive of protein and fibre Digestibility of protein from forages is highest in rabbits as compared other herbivores. Animal Nutrition PVNRTVU Digestibility of fibre is lowest in rabbit as compared to other herbivorous animals Contribution of energy from fibrous sources is comparatively less in rabbits.  - Fermentation in Caecum and Nutrient Supply Proportions of volatile fatty acids in the caecal contents are of the order 60 to Animal Nutrition PVNRTVU 70% acetic, 15 to 20% butyric and 10 to 15% propionic acid. It is estimated that the rabbit obtains upto 40 % of its maintenance energy requirements from the volatile fatty acids produced in the hind gut. Bacteria in the gut synthesize B complex vitamins and vitamin K in adequate quantities; Thus, B complex vitamins and vitamin K need not be supplied through the diet.  Significance of Different Nutrients in the Diets of Rabbits- Energy Dietary energy content is the most important factor controlling feed intake in rabbits Animal Nutrition PVNRTVU Energy is needed for different physiological functions-Maintenance, growth, gestation and lactation Energy is derived mainly from dietary carbohydrates and fats  Carbohydrates Animal Nutrition PVNRTVU Starch, sugars and digestible fibre in the diet supply energy to rabbits Rabbits efficiently digest starch, the major carbohydrate in cereal grains No special problems are encountered with the use of starch or sugars in the diet  Fibre Rabbits rations should contain a minimum of 15 % crude fiber to promote intestinal motility and minimize intestinal disease. Fiber may also absorb bacterial toxins and eliminate them via the Animal Nutrition PVNRTVU hard feces. Minimum amount of indigestible fibre is needed for proper digestive system functioning and health particularly in growing rabbits Fibre requirement is expressed in terms of ADF. An increased incidence of intestinal problems occurs on low fiber diets. On the other hand. high-fiber diets may result in an increased incidence of cecal impaction and mucoid enteritis.  Lipids Fat concentration in the diet usually ranges from 2 to 2.5% Needed as a source of essential fatty acids which can obtained from various Animal Nutrition PVNRTVU feed ingredients used in the diets In intensive system, fats may be added in diet from 1 to 3% In lactating does diet, fat is added to increase energy concentration of diet and energy intake In weaning rabbits, dietary addition of fat may improve body condition, stimulate development of immune system and health  Protein and Amino acids Protein and amino acids are needed for different physiological functions in rabbit Animal Nutrition PVNRTVU For rapid growth, rabbits are dependent upon adequate quantities of dietary essential amino acids. Bacterial protein synthesis in the cecum apparently does not make a large contribution to the essential amino acid needs of the young rabbit. It may help to maintain nitrogen equilibrium in mature animals fed poor-quality proteins. Rabbit is able to utilize proteins efficiently in forage plants. Sufficient level of lysine, methionine and arginine is needed in the diet of growing rabbit  Minerals Does milk is high in calcium. Relatively more calcium is needed in the diets of lactating does The bacterial action in the cecum and colon renders plant Animal Nutrition PVNRTVU phosphorus available and phytate phosphorus is well utilized in rabbits At birth, rabbits have a very large iron reserve so the newborn are not dependent on a supply of iron in the milk. Protection against peroxide damage appears to be more dependent on vitamin E than on selenium in the rabbit. Utilization of cobalt by the bacterial flora for synthesis of vitamin B12 is much more efficient in the rabbit than in ruminants and other non-ruminants  Vitamins Requirements for various members of the vitamin B complex are partially or even completely satisfied through the routine practice of caecotrophy. Animal Nutrition PVNRTVU Fat soluble vitamins should be supplemented through diet Animal Nutrition PVNRTVU Thank You