Authors : Goonewardene L.A , Z. Wang , E. K. Okine , M. A. Price , Z. Wang , J. A. Basarab , L. A. Goonewardene , Jr D. H. Crews, P. Ramsey , K.L. Lyle , N. French , E.K. Okine and S.S. Moore
Abstract: The objective of the study was to compare growth and maturing parameters of seven classes of meat livestock, derived by fitting the Richards equation and identify efficiencies and inefficiencies of growth and production relative to lifetime and slaughter. The livestock included elk, cattle (cows, bulls andsteers), goats (wether), pig (barrows), broiler chickens and emus. The mature weights derived were elk = 406.9, cows = 551.4, steers = 598.0, bulls = 624.9, goat-wethers = 44.5, pig-barrows = 195.4, broiler = 4.6 and emu = 49.5, all in kg. The absolute growth rates derived were elk = 150, cows = 496, steers = 1927, bulls = 2065, goat- ether = 147, pig-barrows = 468, broiler = 54 and emu = 68.4, all in g d . In general, all classes of livestock were between 19.8 - -136.2% mature at inflection and between 49 - 91% mature at slaughter. Broilers were 32 days old at inflection and slaughtered at 40 days, which was eight days post-inflection whereas, emus were slaughtered 435 days post inflection. Cattle were slaughtered when they were 84% mature and 259-278 days post inflection, while pigs were 49% mature at slaughter and 90 days post inflection. Although the time at slaughter is set by industry and often determined by the level of carcass finish, consideration should be given to biological growth efficiency, as the longer a species is held beyond inflection the more inefficient it becomes. In addition, the risk of death, sickness, increased feed costs per kg of gain, less tender beef with more fat, are usually associated with meat from older livestock.
Goonewardene L.A , Z. Wang , E. K. Okine , M. A. Price , Z. Wang , J. A. Basarab , L. A. Goonewardene , D. H. Crews, Jr , P. Ramsey , K.L. Lyle , N. French , E.K. Okine and S.S. Moore , 2005. A Comparison of Growth, Efficiency and Maturing Patterns of Meat. Journal of Animal and Veterinary Advances, 4: 825-830.