Document Type: Review Article


Lecturer of Payam Noor University, Qom, Iran.


The number of lambs sold per ewe mated in the breeding flock has a considerable impact on sheep operation profitability. This depends primarily on fertility, prolificacy (# of lambs), and lamb survival, mothering ability, milk production of the ewe and lamb growth rate. Optimal reproduction does vary by environment and management system – some sheep operations don’t want a lambing rate over 200%. Breed type plays an important part in the prolificacy as well as their tendency to an extended breeding season. Nevertheless, the pounds of lamb produced per ewe mated in the flock affects profitability.


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