04 Lipid Metabolic Disorders 大学动物营养学课件 英文版.pptVIP

Lipid Use and Metabolic Disorders Fatty Acid Profile Major fatty acids in feed fats C16:0 Palmitic acid C16:1 Palmitoleic acid C18:0 Stearic acid C18:1 Oleic acid C18:2 Linoleic acid C18:3 Linolenic acid Unsaturated:saturated ratio = C16:1 + C18:1 + C18:2 + C18:3 C16:0 + C18:0 Types of Feed Fats and Oils Oils Vegetable oils Soapstocks = FA + salt ion (Na, K) Fats Tallow, lard Choice white grease Restaurant grease Blends Oils + fats Fat Sources Oil sources Soapstock Vegetable oil Restaurant grease Fat sources Pig and cattle tissues from: Slaughter plants, lockers Grocery stores Deadstock Age and Energy Values (Poults) U:S Ratio and Energy Values U:S Ratio and Energy Values Free Fatty Acids and Energy Values Heat Damage and Energy Values Fat Deficiency Carnivore diets with under 5% total fat can induce essential fatty acid deficiencies Symptoms include dull hair coat, reproductive failure (testicular underdevelopment, anestrus, and lack of libido), and dry, scaly skin Adding essential fatty acids to diets with over 15% total fat not beneficial Essential fatty acids only required at ~1% of diet Birds on deficient diet show poor feathering Difficult to create deficiency in ruminants or cecal fermenters (caprophagy) Microbes synthesize adequate amounts of fats Tolerance of Fats in Diets Horses can tolerate fat levels up to 20% of their diet Dogs can tolerate up to 40% fat in diet Ruminants can only tolerate 7-8% fat in diet, because more than that adversely affects microbes and decreases feed consumption and fiber digestion Can be fed more if fed as bypass fat EXCEPTION: Newborn ruminants can be fed over 30% fat diets - essentially a monogastric species Over-feeding Fats Overfeeding fats leads to more fat deposition than overfeeding carbohydrates ~95% of extra energy deposited as fat compared to 75% for carbohydrate overfeeding Shorter chain fatty acids (not included in lipoproteins and chylomicrons) have effects closer to carbohydrates Induction of fatty liver