Skip to main content
ARS Home » Research » Publications at this Location » Publication #68473
Title: BODY COMPOSITION AND ENERGY UTILIZATION BY STEERS OF DIVERSE GENOTYPES FED A HIGH-CONCENTRATE DIET DURING THE FINISHING PERIOD: I. ANGUS, BELGIAN BLUE, HEREFORD, AND PIEDMONTESE SIRES.

Author
item Ferrell, Calvin
item Jenkins, Thomas

Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/24/1997
Publication Date: N/A
Citation: N/A

Interpretive Summary: Objectives of the study were to determine the influence of Angus, or Hereford, Belgian Blue or Piedmontese sires and Angus, Hereford or MARC III (1/4 Angus, Hereford, Red Poll, and Pinzgauer) dams on body composition and energy utilization of crossbred steers. The data reported herein documented differences among Angus/Hereford, Belgian Blue, and Piedmontese as sire breeds for several important carcass, body composition, and composition of gain traits. For many traits, dam breed (in this study, Angus, Hereford, and MARC III) effects were important. Data were presented which indicated the relationship between energy gain and metabolizable energy intake was not linear above maintenance. Rate of gain approached a maximum as ME intake increased.

Technical Abstract: Objectives of the study were to determine the influence of Angus (A), or Hereford (H), Belgian Blue (B) or Piedmontese sires and A, H or MARC III (1/4 A, H, Red Poll, and Pinzgauer) dams on body composition, and energy utilization of crossbred steers. Steers were assigned, by sire(S) and dam(D) breed, to be killed as initially, limit-fed, or fed ad libitum for 140 d. The statistical model included treatment(T), sire breed, dam breed, and the interactions between sire or dam breed and nutritional treatment. All traits were influenced (P < .05) by T. Empty body composition and composition of gains were influenced (P < .10) by S. Dam breed influenced (P < .10) DM and ME intake, and rates of water, fat, protein, and energy gains. Rates of ME intake, and live weight, empty body weight, water, protein, ash, and energy gains, were influenced (P < .05) by D x T. Neither S nor D influenced (P > .10) regressions of heat production on ME intake. Fasting heat production and maintenance were estimated to be 80.6 and 124.4 kcal ME/kg*.75/d. The nonlinear relationship between energy gain (Y, kcal/kg*.75/d) and ME intake (X, kcal/kg*.75/d) was Y = 74.69 * (1-2.60 * exp(-.0159*(ME-80.597))), indicating energy gain approached an asymptote (74.69) as ME intake increased. This relationship also implies efficiency of ME use for gain decreased as ME intake increased.