Skip to main content
ARS Home » Research » Publications at this Location » Publication #68387
Title: CHANGES IN PROPORTIONS OF EMPTY BODY DEPOTS AND CONSTITUENTS FOR NINE BREEDS OF CATTLE UNDER VARYING FEED AVAILABILITIES

Author
item Jenkins, Thomas
item Ferrell, Calvin

Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/17/1996
Publication Date: N/A
Citation: N/A

Interpretive Summary: Feeding standards provide descriptions of nutrient needs for cow/calf producers. Energy expenditure for maintenance in the cow herd needs to be accurately predicted. Breeds of cattle vary in maintenance requirements. Part of the differences may be attributable to variation in proportions of body components. Mature cows of different breeds attain weight stasis at different fractions of a breed standard reference weight. Relative to standard reference weight, variation exists among breeds for proportions of chemical composition of the carcass, offal and hide. This variation may contribute to breed differences in maintenance requirement that effect production efficiency of the cow herd.

Technical Abstract: Mature cows (N = 146) representing Angus, Braunvieh, Charolais, Gelbvieh, Hereford, Limousin, Pinzgauer, Red Poll, and Simmental were slaughtered to contribute to the investigation of the effect of varying feed availabilities on body composition. Weights recorded at the time the cows were placed on feed were used to set daily rations at four rates within each breed (55, 76, 96, and 111 g DM/wt**75/d). Cows remained on their assigned daily feed allotment during their stay on the study (3 to 5 years). Within breed relationships between proportions of fat and empty body (sum of fat, ash, water, and protein from the three body pools of hide, offal, and carcass) were used to estimate empty body weight at 251 g fat/kg (standard reference body weight) for each of the nine breeds. Proportions of offal, carcass, hide, chemical constituents, and selected abdominal and thoracic organs relative to empty body weight from animals that attained weight stasis were regressed on one minus the ratio of individual actual empty body weight/breed standard reference weight. Among mature cows attaining weight stasis at varying feeding rates, the proportion of offal remained constant, proportions of fat in carcass, hide and offal increased with increasing feed level, while proportions of water and protein decreased. Significant variation (P < 0.01) attributable to breed in proportions of carcass, offal, hide, chemical constituents of the hide and offal, water and protein of the carcass and selected organs was observed.