Project Number: WVA00140
CRIS Number: 0179944
INCREASING FARM INCOME BY A STRATEGIC SHIFT IN BREEDING TIME FOR EWE FLOCKS
Investigators: Lewis, P. E., Inskeep, E. K., Smith, D. K., Rayburn, E., Mcconnell, T. R.
Performing Department: Animal & Veterinary Science -- 1877
Start Date: 10/01/1998
Termination Date: 09/30/2003
Reporting period: 01/01/2001 to 12/31/2001
Progress Report:
The West Virginia Sheep Management Project continues to have a very positive impact on the WV sheep industry. The demand of producers for services from the project continues to increase and the project newsletter enjoys a wide circulation. In cooperation with the WV State Department of Agriculture the project has received a grant from the Federal-State Marketing Improvement Program to develop a comprehensive database for lamb marketing in WV. The initial surveys to producers is currently being conducted. A study on the ram effect in fall-born ewe lambs was completed. Ram introduction by itself, but not progesterone alone, induced ovulation in fall born ewe lambs during seasonal anestrus. Ram introduction combined with progesterone and estrogen resulted in the best estrous response (81.8%). In conclusion, the reduction in reproductive efficiency of fall born ewe lambs compared to spring born lambs to respond to out-of-season breeding protocols is not due to the lack of the ram effect, but may be related to inadequate estrogen production or a reducted sensitivity to estrogen. We are continuing to evaluate the effect of Follicle Stimulating hormone therapy to increase ovulation rate and prolificacy in the out-of-season breeding programs.
Publications:
Knights, M., T. Hoehn, P. E. Lewis and E. K. Inskeep.2001 Effectiveness of intravaginal progesterone inserts and FSH for inducing synchronized estrus and increasing lambing rate in anestrous ewes. J. Anim. Sci. 79:1120-1131.
Knights, T. D. Maze, P. J. Bridges, P. E. Lewis, E. K. Inskeep. 2001 Short-term treatment with a controlled internal drug releasing (CIDR) device and FSH to induce fertile estrus and increase prolificacy in anestrous ewes. Theriogenology 55:1181-1191.
Impact:
The shift to fall lambing systems continues to be more profitable to WV producers. Reproductive efficiency of the proposed systems continues to be promote more adoption of the system by producers. Recent changes in the funding of the predation control program for WV will impact significantly the interest in the Sheep Management Project.