2. ENERGY EVALUATION OF FEEDS. I. Monogastric Animals István HULLÁR associate professor (2010.) Aim: to express the energy requirement of animals and the energy content of their feeds by the same unit.

3. FLOW DIAGRAM OF ENERGY TERMS GE (Gross Energy)  - Faecal Energy loss DE (Digestible Energy)  - Urinary and Gaseous Energy loss ME (Metabolizable Energy)     - Heat increment NEm NE l NEg (Net Energy) (m: maintenance; l: lactation; g: gain).

4. Unit of Measure 1. Earlyer: calorie (cal); 2. System International (SI): Joule (J); 3. 1 cal = 4.184 J; 4. 1000 J = 1 kJ; 5. 1000 kJ = 1 MJ; 6. Energy content of feeds: kJ/g or MJ/kg; 7. 1 kJ/g = 1 MJ/kg.

5. DIGESTIBLE ENERGY (DE) GE  - Faecal Energy DE (MJ/kg) Pig, Horse, Rabbit

6. DE content of feeds I. Calculation according to the experimental data (F i *GE F ) – (FA*GE Fa ) DE (kJ/g) =  where Fi F i = Feed intake (g, DM); GE F = Gross Energy content of Feed (kJ/g, DM); FA = Faeces output (g, DM); GE Fa = GE content of Faeces (kJ/g, DM).

7. DE content of feeds F i = 6000 g, DM; GE F = 18 kJ/g, DM; FA = 2500 g, DM;GE Fa = 7.32 kJ/g, DM; (6000*18) – (2500*7.32) DE (kJ/g) =  = 6000 108000 – 18300 DE (kJ/g) =  = 6000 = 14.95 kJ/g.

8. DE content of feeds II. Prediction according to the digestible nutrients (Equation of Rostock) DE pig (MJ/kg) = 0.0242*DCP + 0.0394*DEE + 0.0194*DCF + 0.0170*DNFE where DCP = Digestible Crude Protein (g/kg); DEE = Digestible Ether Extract (g/kg); DCF = Digestible Crude Fibre (g/kg); DNFE = Digestible N-free Extract (g/kg).

9. DE content of feeds E.g. Prediction of the DE content of extracted soybean meal (MJ/kg) DE pig (MJ/kg) = 0.0242*DCP + 0.0394*DEE + 0.0194*DCF + 0.0170*DNFE Nutrients CP EE CF NFE g/kg 480 10 35 288 Dig. Coeff. *0.92 *0.40 *0.65 *0.97 Dig. Nutr. g/kg = 441.6 = 4.0 = 22.1 = 279.4 Factors *0.0242 *0.0394 *0.0194 *0.0170 DE MJ/kg = 10.687 = 0.158 = 0.429 = 4.750 16.024  

10. ME content of feeds GE  - Faecal Energy loss DE  - Urinary and Gaseous Energy loss ME (MJ/kg) Poultry: AMEn (Apparent Metabolizable Energy corrected to zero N retention.)

11. Calculation of the AME content of feeds (F i *GE F ) – (E*GE E ) AME (kJ/g) =  where Fi F i = Feed intake (g, DM); GE F = Gross Energy content of Feed (kJ/g, DM); E = Excreta output (g, DM); GE E = GE content of Excreta (kJ/g, DM).

12. Calculation of the AME content of feeds Adult Bird: N intake = N output  zero N retention. Growing Bird: N intake > N output  positive N balance (uric acid: 34.4 kJ/g N).

13. Calculation of the AME content of feeds Adult Bird (N balance = 0) 1000 KJ – 200 KJ 800 kJ AME (kJ/g) =  =  = 11,43 kJ/g 70 g 70 g Growing Bird (N balance = + 1 g): -34,4 kJ 1000 KJ – 165,6 KJ 834,4 kJ AME (kJ/g) =  =  = 11,92 kJ/g. 70 g 70 g

14. Calculation of the AMEn content of feeds Adult Bird (N balance = 0) 1000 KJ – 200 KJ 800 kJ AME (kJ/g) =  =  = 11,43 kJ/g 70 g 70 g Growing Bird (N balance = + 1 g): -34,4 kJ 1000 KJ – 165,6 KJ – 34,4 kJ AMEn (kJ/g) =  = 70 g 1000 KJ – 200 KJ 800 kJ AMEn (kJ/g) =  =  = 11,43 kJ/g. 70 g 70 g