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ARS Home » Plains Area » Clay Center, Nebraska » U.S. Meat Animal Research Center » Genetics and Animal Breeding » Research » Publications at this Location » Publication #357010

Research Project: Developing a Systems Biology Approach to Enhance Efficiency and Sustainability of Beef and Lamb Production

Location: Genetics and Animal Breeding

Title: Status of evaluation of three maternal lines under pasture lambing management conditions at USMARC

item Freking, Bradley - Brad

Submitted to: World Wide Web
Publication Type: Other
Publication Acceptance Date: 9/18/2018
Publication Date: 9/19/2018
Citation: Freking, B.A. 2018. Status of evaluation of three maternal lines under pasture lambing management conditions at USMARC. World Wide Web [online]. Available:

Interpretive Summary:

Technical Abstract: Reducing labor costs per ewe is one of the best opportunities to increase profitability and attract new investments to the U.S. sheep industry as we look to compete with imported products for the potential growing domestic consumption of lamb. One approach is to use “easy care” genetics in a low-input, pasture-lambing production system. The approach requires strategic use of breeds that provide improved prolificacy, while still able to balance mothering ability and transmit lamb behavior effects that enhance survival. Research has indicated that several kinds of ½ Romanov – breed crosses are quite capable of rearing triplet lambs on pasture unaided. The USMARC has created a new hair sheep composite maternal line that is ½ Romanov, ¼ White Dorper, and ¼ Katahdin. This composite is being directly compared for ewe productivity traits relative to the Katahdin and Polypay breeds in both purebred and terminal sire mating systems. The Easycare composite exceeded performance levels of both the Katahdin and Polypay breeds for reproductive rates by producing an additional 0.4 more lambs at weaning per ewe exposed. This difference was realized as an additional 4.3 kg at 20 weeks of age more lamb per ewe exposed compared to Katahdin, and 2.7 kg more than Polypay ewes. Utilizing appropriate genetics resources for increased reproduction under low input management systems is attainable, by allowing ewes to rear triplets unaided. Utilizing both maternal and individual lamb heterosis is the most important aspect of increasing reproductive performance for the U.S. sheep industry under these conditions.