Correlated responses in body composition and fat partitioning to divergent selection for yearling growth rate in Angus cattle.

摘要: Abstract Body composition data were collected in a serial slaughter experiment on 91 Angus steers produced after 12 years of divergent selection for yearling growth rate. Steers born 1986 and 1987 from lines selected high (High Line) low (Low rate birth to weaning, an unselected line (Control slaughtered at 0 (birth) circa 7, 12, 27, 35 45 months age. Weights obtained dissected carcass muscle, bone, subcutaneous intermuscular fat, non-carcass fat depots, visceral organs, hide head, tail distal legs. At the same stage maturity empty body weight or total components partitions similar proportion their mean mature weights all three lines. 360 kg, High Line had smaller proportions higher bone than other two lines, Low muscle relative Relative Line, Control required 85 175 additional days, respectively, attain this weight. Mean (body minus urine gut contents) was 666±17 (standard error, S.E.) 588±18 kg 512±16 High, steers, respectively. There no significant (P