Open AccessEFFECTS OF FEEDING PROGRAMS AND DIET ENERGY ON RATE OF GAIN, EFFICIENCY OF DIGESTIBLE ENERGY UTILIZATION, AND CARCASS GRADES OF STEERS
Author(s) -
R. Hironaka,
Bettina Sonntag,
G. C. Kozub
Publication year - 1979
Publication title -
canadian journal of animal science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.377
H-Index - 64
eISSN - 1918-1825
pISSN - 0008-3984
DOI - 10.4141/cjas79-048
Subject(s) - feedlot , zoology , weight gain , body weight , biology , feeder cattle , carcass weight , endocrinology
Two experiments were conducted to obtain biological data to expand a linear programming (LP) model for feedlot cattle management and to test that model by feeding model-formulated diets of different digestible energy (DE) concentrations. In the first experiment, 76 steers averaging 210 kg in body weight were fed an all-concentrate diet to gain at a low rate of about 0.5 kg/day (L), a medium rate of about 0.8 kg/day (M), or at a high rate when the diet was fed ad libitum (H). The five feeding programs were LMH, HML, MMM, HHH, and LLH. The HHH steers gained faster (1.15 kg/day) than those in the other groups (P 0.05). The steers restricted in feed during part of the feeding period produced leaner carcasses (P < 0.01) than those that were full-fed throughout. In the second experiment, 75 Hereford or Hereford-Angus steers averaging about 200 kg in body weight were fed diets differing in DE concentrations to test the LMH program of the LP model. The rate of gain declined and DE/gain ratio increased as the DE concentration of the diet was decreased. Carcass measurements and grades were similar among groups fed diets differing in DE concentrations.