Fish Nutrition and Feeding Carcass Characteristics of Various Food Animals Source Dress Out (%) Characteristic of Carcass Refuse Lean Fat Food Energy (%) (%) (%) (kcal/100 g of edible tissue) Channel Catfish 60 14 81 5 112 Beef 61 15 60 25 147 Pork 72 21 54 26 147 LaDon Swann Mississippi-Alabama Sea Grant Consortium Auburn University Chicken 72 30 65 9 115 Nutritional Comparisons of Various Proteins Nutrient Requirements Energy requirements are lower for fish. Fish require some lipids such as omega-3 s that warm-blooded animals do not. Fish can absorb some minerals from water through the gills. Most fish can t synthesize ascorbic acid (Vitamin C). Fish Diversity Because there are so many fish species, extreme variation in fish digestive systems exist among the families. Types of GI Tract Herbivores small stomachs and long intestine tilapia carp (stomach is 3X body length) Omnivores moderate size stomach and intestine catfish Carnivores large stomach and short intestine trout striped bass
Terms Bioenergetics: Study of the balance between energy intake in the form of food and the energy utilization by animals 1 Calorie: energy required to raise 1 g of water 1 C Kilocalorie (kcal): 1,000 calories Mega Kilocalorie: 10,000 calories More Terms Intake Energy (IE): gross energy content of food source Digestible Energy (DI): difference between gross energy and energy available to animals Fecal Energy (FE): energy lost through feces Urine Energy (UE): energy lost through urine Gill Energy (ZI): energy lost through the gills Even More Terms Gross Energy Values Metabolizable Energy (ME): difference between DE and energy lost through the FE + UE + ZI Heat Increment (HI): rise in energy expenditure associated with the assimilation of ingested food Maintenance Energy: voluntary activity plus basal metabolism Feeds are based on satisfying maintenance energy PLUS enough nutrition for growth Carbohydrates (Glucose) 3.77 kcal/g Proteins (Casein) 5.84 kcal/g Fat (Soybean oil) 9.28 kcal/g Digestible Energy Feedstuff DE/IE ME/DE Anchovy Meal 0.91 0.94 Soybean Meal 0.79 0.94 Wheat middlings 0.40 0.91 Conversion Efficiency Fish require less energy for protein synthesis. catfish, 0.84 g gain/g food consumed chickens, 0.48 g gain/g food consumed Beef, 0.13 g gain/g food consumed Fish are better at assimilating high protein diets. Fish poorly utilize carbohydrates for energy.
Conversion Efficiency Fate of Nitrogen and Phosphorus in Feed Lower energy cost for protein gain Fish 47 g/mkcal ME Chicken 23 g/mkcal ME Beef 6 g/mkcal ME Protein fed to protein gain is similar among fish, birds, and mammals Fish, 0.36 g protein gain/g protein fed Chicken, 0.33 g protein gain/g protein fed Beef, 0.15 g protein gain/g protein fed Food 100% N 100% P Solids 13% N 60-90% P Effluent 70% N 68% P Retained in Tissues 30% N 32% P Dissolved 87% N 10-40% P Animal Comparison of Feed and Dietary Protein and Energy Among Common Livestock P (%) Feed Composition Energy (kcal ME/g) MEprotein ratio (kcal/g) Wt. Gain/g of diet Efficiency Protein gain/g protein consumed Protein gain/ Mkcal ME consumed (g) Channel Catfish 32 2.7 8.5 0.84 0.36 47 Broiler Chicken 18 2.8 16 0.48 0.33 23 Beef Cattle 11 2.6 24 0.13 0.15 6 Bioenergetics Digestible Energy (DE) % DE = IE - FE IE Metabolizable Energy (ME) % ME = IE (FE - UI - ZI) IE Approximately 85% of nitrogenous wastes pass through gills Heat Increment Heat Increment (HI) of ME is 3-5% in fish vs. up to 30% in mammals. Lower HI is due to the ammonia excretion rather than urea or uric acid. 1 ATP / N in Ammonia 4 ATP / molecule of Urea (2 Nitrogen) 10 ATP/4 N in Uric acid Fish Have Lower Maintenance Requirement Lower Maintenance Energy Rainbow Trout Maintenance Energy = 57kcal/kg bwt to the 0.63 power Mammals Maintenance Energy = 70-83 kcal/kg bwt to the 0.75 power
Why Lower Energy Requirement? Don t have to maintain body temperature (HI) Less energy to maintain position Lose less energy in protein catabolism and excretion of nitrogen Carbohydrates Fish have poor control over glucose levels. Following glucose ingestion, blood glucose levels rise rapidly, but may take hours to decrease. Turnover of glucose in trout is 10X slower than in rats. Proteins Requirements Fingerlings require higher protein than finished fish. 33 g cc (27%) required 4X more than 250 g cc (38%) based on a diet low in energy high energy diet: consumption decreased and 27% wasn t enough Protein and Digestible Energy Requirements by Sizes of Channel Catfish for Protein Synthesis Size (g) Protein (g/100 g fish /day) DE (kcal/100 g fish/day) 3 1.64 16.8 10.2 DE/Protein ratio (kcal/g) 10 1.11 11.4 10.3 56 0.79 9.0 11.4 198 0.52 6.1 11.7 266 0.43 5.0 11.6 Catfish Feed (Floating) Guaranteed Analysis Crude protein not less than 32.0% Crude fat not less than 3.5% Crude fiber not more than 7.0% Ingredients Soybean meal, ground yellow corn, fish meal, brewers' dried yeast, wheat middlings, animal fat preserved with BHA, vitamin A supplement, vitamin B supplement, D-activated animal sterol (source of vitamin D ), DL-methionine, calcium pantothenate, folic acid, niacin supplement, riboflavin supplement, menadione sodium bisulfite (source of vitamin K activity), ascorbic acid, salt, calcium carbonate, ferrous carbonate, manganous oxide, calcium iodate, copper sulfate, cobalt carbonate, zinc sulfate. Feed Formulation Cost of ingredients Nutrient content of ingredients Nutrient requirements Nutrient availability Min.-Max. Max. restrictions of ingredients
Typical Catfish Diet Containing Fishmeal Menhaden fishmeal 8.0 Soybean meal (48% P) 48.2 Corn (ground) 29.2 Rice bran or wheat 10.0 Dicalcium phosphate 1.0 Organic binder 1.5 Fat (sprayed) 0.05 Trace minerals 0.05 Vitamin mix 0.05 Ascorbic acid 0.038 Types of Fish Feed Live Algae Zooplankton By-catch/trash fish Formulated Floating Sinking Mixed Extruded (Floating) Sinking Feeding Rates Feeding Frequency Animals must be fed often enough to satisfy maintenance requirements plus planned growth. Feeding methods Percent Body Weight Percent to feed: range from 1-10% 10% per day Growth Rate Biomass to feed Satiation Feeding Feed as much as the animals will eat in 15-30 minutes Types of GI Tracts Herbivores => Omnivores => Carnivores Size of Animal Larvae => Juveniles => Adults => Broodstock Frequency 1-1010 times per day Alimento composto Dourasoja extra 5H Dourasoja extra 5H matérias primas Proteína bruta 42,1 % Gordura bruta 14,1 % Cinzas brutas 8,4 % Fibras brutas 3,2 % Fósforo 1,2 % Aditivos Vitamina A 5000 UI Vitamina D3 1000 UI Alfa tocoferol - 200 mg Cobre - 13 mg Farinha de Peixe 28 % Bagaço de Soja 21,7 % Trigo Forrageiro 13,0 % Óleo de Peixe 11,0 % Bagaço de Colza 11,0 % Farinha de Sangue 8,0 % Glúten de Milho 4,0 % Ac. Glutâmico (por fermentação) 2,0 % Premistura 0,8 %