Project Type: Research and Education
Funds awarded in 2014: $134,152.00
Projected End Date: 12/31/2016
State: West Virginia
West Virginia University
Breeding replacement ewes to lamb for the first time at 1 year of age increases lifetime productivity of the ewe and overall productivity. Ewe lambs born to fall lambing systems reach the age at which they should attain puberty during spring/summer when reproductive activity is suppressed. As a consequence few ewe lambs can be successfully bred during seasonal anestrous. In this study we demonstrated that gonadotropic stimulation with a gonadotropin mixture containing 240 IU of eCG and 120 IU of hCG following progesterone pre-treatment improved reproductive outcome in fall-born ewe lambs bred during the mid-anestrous period with estrous response and pregnancy rate to the first service period comparable to that observed in adult females. Further, Progesterone pre-treatment alone was sufficient to induce fertile estrus and advance the breeding season in yearlings bred during mid- and late-anestrus.
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This product is associated with the project "Enhancing the productivity of ewe lambs through the use of reproductive management"