Growth and feed conversion efficiency of Dorper and Rambouillet lambs1
- 1 October 2013
- journal article
- Published by Oxford University Press (OUP) in Journal of Animal Science
- Vol. 91 (10), 4628-4632
- https://doi.org/10.2527/jas.2012-6226
Abstract
Data from Dorper and Rambouillet ram lambs (n = 79) were used to estimate breed means for postweaning growth rate, feed intake, feed conversion efficiency (kilograms of gain divided by kilograms of feed consumed), and residual feed intake on a high concentrate diet during the typical age and weight range for U.S. lamb production. Lambs were progeny of 6 unrelated sires/breed and were born over a 2-yr period. Dams of the lambs were a representative sample of Dorper ewes in the United States and Rambouillet ewes in Texas. Data were analyzed using SAS PROC MIXED with a model that included year, breed, birth type, and feeder pen as fixed effects and sire as a random effect. The mean BW at the start of the feeding trial was 31.4 ± 3.7 kg at a mean age of 92.7 ± 9.2 d. Electronic feeders were used to record individual animal feed intake. Growth rate and feed intake were measured for 77 d during the postweaning growth period. Mean ADG was 340 ± 9.2 g for Dorper lambs and 346 ± 8.6 g for Rambouillet lambs. The mean final bodyweight was 58.1 ± 4.8 kg when the mean age was 170 d. Average daily feed intake was 2,223 ± 50 g for Dorper lambs and 2,215 ± 48 g for Rambouillet lambs. Feed conversion efficiency was 0.153 ± 0.003 for Dorper lambs and 0.158 ± 0.003 for Rambouillet lambs. No significant differences were observed between Dorper and Rambouillet lambs for weaning weight, postweaning gain, final weight, feed intake, feed conversion efficiency, or residual feed intake. Growth rate, feed intake, and feed conversion efficiency were similar for Dorper and Rambouillet ram lambs fed from a mean of 31 kg BW and 93 d of age to a mean BW of 58 kg and a mean age of 170 d.Keywords
This publication has 13 references indexed in Scilit:
- Estimates of genetic parameters for feed intake, feeding behavior, and daily gain in composite ram lambs1,2Journal of Animal Science, 2005
- Growth and carcass characteristics of lambs sired by Dorper and Dorset rams.Journal of Animal Science, 2004
- Estimates of genetic parameters and selection strategies to improve the economic efficiency of postweaning growth in lambs.Journal of Animal Science, 2003
- Evaluation of the South African Dorper as a terminal sire breed for growth, carcass, and palatability characteristics1Journal of Animal Science, 2003
- Productive performance of Dorper sheepSmall Ruminant Research, 2000
- A comparative assessment of Dorper sheep in different production environments and systemsSmall Ruminant Research, 2000
- Potential for Hair Sheep in the United StatesJournal of Animal Science, 2000
- Phenotypic characterization of rambouillet sheep expressing the callipyge gene: I. Inheritance of the condition and production characteristics.Journal of Animal Science, 1997
- Effects of Breed and Intake Level on Growth and Feed Efficiency in Ram LambsJournal of Animal Science, 1984
- Efficiency of Feed Use in Beef CattleJournal of Animal Science, 1963