Feed Evaluation V Standards and Concepts of Ration Formulation 1 16 23 Concepts in ration formulation The Nutrition Puzzle Feed components Animal Requirements O utp Anim al Intake ut In Environment p ut Sugars and Starch Fiber Protein Fat Toxins Minerals Vitamins Maintenance Growth Reproduction Lactation Concepts in ration formulation Definition of Balanced Ration I A balanced ration provides nutrients in the correct proportions and amounts to support the physiological functions of an animal II Additionally the required nutrients must be contained within a given diet such that the animal is able to consume the diet within a 24 hour period Formulating rations to optimize animal performance in an environmentally sustainable manner Nutrient availability of feeds Type of ration e g supplement complete ration Nutrient requirement of animals Ration formulation process Feed intake of animals Nutritionally balanced ration for optimal performance 1 2 3 1 Feed Evaluation V Standards and Concepts of Ration Formulation 1 16 23 Feeding Standards for Maintenance Growth Gestation and Lactation Decreased performance Increased costs unit of production Negative environmental impact Deficiency concentration y c n e i c i f e d t n e v e r p o t n o i t a r t n e c n o C t n e i r t u n l a m i t p O n o i t a r t n e c n o c Increased feed Higher feed costs costs Lower Decreased net profitability returns Negative Negative environmental environmental impact impact Excess nutrient concentration Dietary nutrient concentration Dietary EAA Requirements Example Early weaned pigs High EAA requirement y a d g G D A 450 400 350 300 250 200 150 ADG g day Gain Feed ratio 1 2 1 35 1 5 1 65 1 8 1 95 Dietary lysine Owens et al 1995 1 08 1 04 1 0 96 0 92 0 88 0 84 o i t a r d e e f n i a G General comments on feeding standards I Feeding standards are statements of amounts of nutrients e g CP or energy required by animals II Feeding standards and nutrient requirements are synonymous III In general feeding standards are devised to meet the requirements of an average animal for a particular function no safety factor IV Can be expressed as quantity of a nutrient required on daily basis e g g lysine day or in terms of dietary concentration e g lysine V Can be expressed in a variety of units e g NE ME or digestible protein VI Energy is given first priority since it is of greatest amount in a feed and of greatest demand by an animal VII Feeding standards for nutrients e g protein are generally determined separately for various physiological functions of an animal e g growth maintenance reproduction lactation wool growth 4 5 6 2 Feed Evaluation V Standards and Concepts of Ration Formulation 1 16 23 Nutrient requirements of animals I Feeding standards have been developed to provide information on nutrient requirements of major livestock species e g Beef Cattle Horse NRC publications II Research is being routinely conducted to provide more accurate information on nutrient requirements of animals Journal articles experiment station reports etc Factors that affect nutrient requirements of animals I Body weight II Age or stage of maturity III Physiologic function growth lactation IV Level of productivity quantity of milk pregnancy rate of gain V Use of feed additives rumensin VI Use of growth promotants implants or VII Genetics of the animal genetic merit beta agonists for milk VIII Environment heat or cold stress Maintenance energy requirements as a proportion of total feed energy consumed of total energy consumed used to support maintenance requirements Class of livestock Dairy cow 500 kg BW 20 kg milk per day Growing steer 300 kg 1 20 kg ADG Growing pig 50 kg 0 75 kg ADG Growing chickens 1 kg 35 g ADG Beef cow 500 kg 200 kg weaned calf 35 to 45 45 to 55 45 to 55 45 to 55 65 to 75 7 8 9 3 Feed Evaluation V Standards and Concepts of Ration Formulation 1 16 23 Relationship between heat production and body weight Heat production per animal increases as BW increases Red line Heat production per unit of BW decreases as BW increases Blue line Thus predicting an animal s maintenance energy requirement as a function of BW can be challenging Not very useful 12500 10000 7500 5000 2500 0 0 HP day 30 25 20 15 HP kg BW 10 800 400 200 600 Body weight kg Relationship between heat production and body weight Just as surface area of a sphere is not linearly related to its volume HP is not linearly related to BW Numerous animal studies have demonstrated that HP is related to an animal s BW as a function of metabolic body size BW0 75 80 75 70 65 60 55 HP 70 BW0 75 0 200 400 600 800 Body weight kg Metabolic body size concept o Metabolic body size BW0 75 is defined as a mathematical relationship to account for the nonlinear relationship between HP and BW o Metabolic body size is used to confer proportionality to HP or maintenance energy requirements of animals that differ greatly in BW o Metabolic body size is used to predicted maintenance energy requirements of animals Species Cow Pig Sheep Poultry Rat BW kg 500 70 50 2 0 3 Heat production HP kcal day HP per BW ratio kcal kg HP per BW0 75 kcal BW0 75 8 140 1 790 1 020 134 30 16 3 25 6 20 3 67 3 100 0 77 74 56 80 74 10 11 12 4 Feed Evaluation V Standards and Concepts of Ration Formulation 1 16 23 Species differences in using metabolic body size BW0 75 to predict Maintenance Energy Requirements I Beef cattle NEm kcal per day 77 BW0 75 NEm Mcal per day 0 077 BW0 75 II Sheep NEm kcal per day 56 BW0 75 III Dairy cows NEm kcal per day 80 BW0 75 BW0 75 metabolic body weight Effect of BW on NEm requirements in beef cattle 200 lb body weight 200 body weight 2 27 NEm Mcal d 0 077 kg0 75 0 077 200 2 2 0 75 2 27 400 lb body weight 400 body weight 3 81 800 lb body weight 800 body weight 6 41 0 2 4 6 8 NEm requirements Mcal day NEm requirements Mcal day Feeding standards for growth I Net energy requirements for growth NEg are a function of the energy retained in tissue II Energy retained in tissue is a function of the composition of tissue growth III Adipose tissue contains more energy than lean tissue IV NEg retained energy composition of fat lean Depositing more muscle NEg Depositing more fat NEg 13 14 15 5 Feed Evaluation V Standards and Concepts of Ration Formulation 1 16 23 Effect of frame size sex and BW on NEg requirements in beef cattle 500 large frame bull 2 ADG 500 med frame bull 2 ADG 2 30 2 59 500 med …