Feeding Swine - MSU Animal & Range Sciences

NE for Growing/Finishing Beef Cattle California Net Energy System Lofgreen & Garrett, 1968 Net Energy for maintenance NEm Net Energy for gain NEg More useful than TDN Allows more accurate prediction of energy NE for Growing/Finishing Beef Cattle

NEm ability of feed to meet energy reqmt for maintenance NEg ability of feed to meet energy reqmt for gain Maintenance energy must be met first Then any additional energy can be used for gain NE for Growing/Finishing Beef Cattle

NE values of feeds + feed intake can be used to: Predict gain on particular diet Predict amount of feed required for particular gain (programmed feeding) NE for Growing/Finishing Beef Cattle Two NE values for feeds

Feed energy is used more efficiently for maintenance than for gain NEm values always higher than NEg Example NE System 715 lb yearling steers (1,300 lb finished) From feed records, consuming 16 lb (7.26 kg) of diet which contains: 2.09 Mcal/kg NEm

1.42 Mcal/kg NEg 5 Example NE System NEm required per day is based only on body weight (Table 9) = 5.89 Mcal/day 6

Example NE System requirement Energy in feed 5.89 Mcal NEm/2.09 Mcal NEm/kg = 2.82 kg of diet needed for maintenance Total intake is 7.26 kg

7.26 kg 2.82 kg = 4.44 kg remaining Energy in feed for gain 4.44 kg x 1.42 Mcal/kg NEg = 6.30 Mcal available for gain 7 Example NE System 6.30 Mcal available for gain

From Table 9 need 6.94 Mcal to gain 3.99 lb/day 8 Example NE System From Table 9 need 6.94 Mcal to gain What we have 3.99 lb/day

available for gain Extrapolate: 3.99 lb/6.94 Mcal = x lb/6.30 Mcal x = 3.62 lb/day Predicted ADG 9 Example NE System

Feed efficiency Expressed 2 ways: lb feed/lb gain 16 lb/3.62 lb = 4.4 or lb gain/100 lb feed 3.62 lb/0.16 lb = 22.6 10