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ARS Home » Plains Area » Clay Center, Nebraska » U.S. Meat Animal Research Center » Livestock Bio-Systems » Research » Research Project #442610

Research Project: Discovery of Novel Traits to Improve Efficiency and Sustainability of Different Sheep Production Systems

Location: Livestock Bio-Systems

Publications (Clicking on the reprint icon Reprint Icon will take you to the publication reprint.)

Genome-wide association and functional annotation analyses reveal candidate genes and pathways associated with various ewe longevity indicators in U.S. Katahdin sheep - (Peer Reviewed Journal)

Estimation of genetic parameters and genetic trends for ewe longevity indicators in U.S. Katahdin sheep Reprint Icon - (Peer Reviewed Journal)
Pinto, L.F.B., Lewis, R.M., Rocha, A.O., Freking, B.A., Wilson, C.S., Murphy, T.W., Nilson, S.M., Burke, J.M., Brito, L.F. 2025. Estimation of genetic parameters and genetic trends for ewe longevity indicators in U.S. Katahdin sheep. Journal of Animal Science. Article skaf125. https://doi.org/10.1093/jas/skaf125.

Estimates of genetic parameters for growth, reproduction, wool, and carcass traits in the U.S. Polypay sheep - (Abstract Only)
Saleem, A.H., Rocha, A.O., Yazar Gunes, H., Murphy, T.W., Lewis, R.M., Brito, L.F. 2025. Estimates of genetic parameters for growth, reproduction, wool, and carcass traits in the U.S. Polypay sheep [abstract]. In proceedings: Plant and Animal Genome Conference. January 10-15, 2025, San Diego, CA. P237.

Sheep GEMS: Genetic aspects of udder health - (Popular Publication)
Murphy Jr, T.W. 2025. Sheep GEMS: Genetic aspects of udder health. Sheep Industry News. February 14, 2025. p. 5-7.

Sheep GEMS: Economic impacts of udder diseases - (Popular Publication)
Murphy Jr, T.W. 2025. Sheep GEMS: Economic impacts of udder diseases. Sheep Industry News. January 31, 2025. p. 5.

Impacts of birth season and production system on gastrointestinal parasitism and growth in Katahdin lambs Reprint Icon - (Peer Reviewed Journal)
Murphy, T.W., Burke, J.M., Hess, A.S., Miller, J.E., Wood, E.L., Acharya, M. 2024. Impacts of birth season and production system on gastrointestinal parasitism and growth in Katahdin lambs. Translational Animal Science. 8. Article txae174. https://doi.org/10.1093/tas/txae174.

Factors affecting the length of productive life in U.S. Katahdin ewes Reprint Icon - (Peer Reviewed Journal)
Pinto, L.F.B., Lewis, R.M., Rocha, A.O., Freking, B.A., Murphy, T.W., Wilson, C.S., Nilson, S.M., Burke, J.M., Brito, L.F. 2025. Factors affecting the length of productive life in U.S. Katahdin ewes. Journal of Animal Science. 103. Article skae361. https://doi.org/10.1093/jas/skae361.

Adding gastrointestinal parasite resistance to the breeding objective in hair sheep: Initial steps Reprint Icon - (Peer Reviewed Journal)
Forbes, R.M., Murphy, T.W., Burke, J.M., Notter, D.R., Spangler, M.L., MacNeil, M.D., Lewis, R.M. 2024. Adding gastrointestinal parasite resistance to the breeding objective in hair sheep: Initial steps. Journal of Animal Science. 102. Article skae327. https://doi.org/10.1093/jas/skae327.

Sheep GEMS provides project update - (Trade Journal)
Freking, B.A. 2024. Sheep GEMS provides project update. Sheep Industry News. ASI Weekly Newsletter. October 4, 2024. p.4-5.

Sheep GEMS update: Using genotypes to reduce Ovine Progressive Pneumonia (OPP) susceptibilty - (Trade Journal)
Freking, B.A. 2024. Sheep GEMS update: Using genotypes to reduce Ovine Progressive Pneumonia (OPP) susceptibilty. Sheep Industry News. ASI Weekly Newsletter. August 30, 2024. p.2-3.

Serum energy metabolite and mineral concentrations in a contemporary flock of Western white-faced ewes during the periparturient period Reprint Icon - (Abstract Only)
Laverell, D.M., Murphy, T.W., Engle, T.E., Kersh, A.J., Mills, J.B., Stewart, W.C. 2024. Serum energy metabolite and mineral concentrations in a contemporary flock of Western white-faced ewes during the periparturient period [abstract]. Journal of Animal Science Supplement. 102(Supplement 3):484-485. https://doi.org/10.1093/jas/skae234.550.

Heritability estimates for longevity-related traits in U.S. Katahdin ewes Reprint Icon - (Abstract Only)
Pinto Batista, L.F., Lewis, R.M., Rocha, A.O., Nilson, S.M., Murphy, T.W., Wilson, C.S., Freking, B.A., Burke, J.M., Brito, L.F. 2024. Heritability estimates for longevity-related traits in U.S. Katahdin ewes[abstract]. Journal of Animal Science Supplement. 102(Supplement 3):452-453. https://doi.org/10.1093/jas/skae234.511.

Survival analyses of the productive life in U.S. Katahdin ewes Reprint Icon - (Abstract Only)
Pinto Batista, L.F., Lewis, R.M., Rocha, A.O., Nilson, S.M., Murphy, T.W., Wilson, C.S., Freking, B.A., Burke, J.M., Brito, L.F. 2024. Survival analyses of the productive life in U.S. Katahdin ewes[abstract]. Journal of Animal Science. 102(Supplement 3):441-442. https://doi.org/10.1093/jas/skae234.500.

Milk microbiome in the first month of lactation and at weaning from ewes supplemented with zinc pre- and postpartum Reprint Icon - (Peer Reviewed Journal)
Knuth, R.M., Page, C.M., Stewart, W.C., Hummel, G.L., Woodruff, K.L., Whaley, J.R., Springer, A.L., Austin, K.J., Murphy, T.W., Bisha, B., Cunningham-Hollinger, H.C. 2024. Milk microbiome in the first month of lactation and at weaning from ewes supplemented with zinc pre- and postpartum. Journal of Animal Science. 102. Article skae163. https://doi.org/10.1093/jas/skae163.

Flashtags: Evaluating a novel deterrent to reduce livestock depredation - (Peer Reviewed Journal)

Adding parasite resistance to the breeding objective in hair sheep Reprint Icon - (Abstract Only)
Forbes, R.M., Murphy, T.W., Burke, J.M., Lewis, R.M. 2024. Adding parasite resistance to the breeding objective in hair sheep [abstract]. Journal of Animal Science Supplement. 102(Supplement 2):32-33. https://doi.org/10.1093/jas/skae102.039.

Sheep GEMS Update: Lambing assistance and udder health scores - (Popular Publication)
Lewis, R., Murphy, T., Freking, B., Burke, J. 2024. Sheep GEMS Update: Lambing assistance and udder health scores. Eastern Alliance for Production Katahdins Newsletter. Winter 2023 Newsletter. p. 10-11.

Meet the Research Leaders at NSIP - (Popular Publication)
Murphy, T.W., Brito, L.F., Hess, A.S., Lewis, R.M. 2023. Meet the Research Leaders at NSIP. Sheep Industry News. (27)8:14-15.

The potential value of international sheep evaluations - (Popular Publication)
Hess, A.S., Brito, L.F., Murphy, T.W. 2023. The potential value of international sheep evaluations. Sheep Industry News. (27)8:30-31.

Birth season and production system effects on post-weaning growth and gastrointestinal nematode infection of Katahdin lambs Reprint Icon - (Abstract Only)
Murphy, T.W., Hess, A.S., Miller, J.E., Burke, J.M. 2023. Birth season and production system effects on post-weaning growth and gastrointestinal nematode infection of Katahdin lambs [abstract]. Journal of Animal Science Supplement. 101(Supplement 3):306-307. https://doi.org/10.1093/jas/skad281.366.

Genetic parameter estimates of post-weaning growth and gastrointestinal nematode infection traits of Katahdin lambs Reprint Icon - (Abstract Only)
Hess, A.S., Murphy, T.W., Miller, J.E., Burke, J.M. 2023. Genetic parameter estimates of post-weaning growth and gastrointestinal nematode infection traits of Katahdin lambs [abstract]. Journal of Animal Science Supplement. 101(Supplement 3):303. https://doi.org/10.1093/jas/skad281.362.

Characterization of Katahdin lamb carcasses in a traditional lamb marketing context Reprint Icon - (Abstract Only)
Phillips, M.K., Gifford, C., Murphy, T.W., Freking, B.A., Newman, C.E., Ritchie, C.R., Stewart, W.C. 2023. Characterization of Katahdin lamb carcasses in a traditional lamb marketing context [abstract]. Journal of Animal Science Supplement. 101(Supplement 3):658-659. https://doi.org/10.1093/jas/skad281.766.

A journey into sheep GEMS - (Popular Publication)
Lewis, R.M., Brito, L., Freking, B., Burke, J.M., Murphy, T., Taylor, J.B., Wilson, C.S., Nilson, S., Arisman, B., Oliveira Rocha, A., Yazar Gunes, H. 2023. A journey into sheep GEMS. Sheep Industry News. 27(8):24-26.

Serum mineral and vitamin concentrations in central performance tested Rambouillet rams with and without angular limb deformities Reprint Icon - (Abstract Only)
Laverell, D.M., Murphy, T.W., Smylie, J.M., Kersh, A., Engle, T.E., Stewart, W.C. 2023. Serum mineral and vitamin concentrations in central performance tested Rambouillet rams with and without angular limb deformities [abstract]. Journal of Animal Science Supplement. 101(Supplement 3):660-661. https://doi.org/10.1093/jas/skad281.768.

Is scrotal ultrasound a useful tool in ram breeding soundness examination? Reprint Icon - (Abstract Only)
Murphy, T.W., Freking, B.A., Wildeus, S., Miles, J.R., Cushman, R., Snider, A.P., Rempel, L.A. 2023. Is scrotal ultrasound a useful tool in ram breeding soundness examination? Journal of Animal Science. 101(Supplement 3):654. https://doi.org/10.1093/jas/skad281.761.

Comparison of three maternal composite sheep breeds managed under pasture lambing and purebred or terminal mating systems: Ewe body weight, reproductive efficiency, and longevity Reprint Icon - (Peer Reviewed Journal)
Murphy, T.W., Freking, B.A., Bennett, G.L. 2022. Comparison of three maternal composite sheep breeds managed under pasture lambing and purebred or terminal mating systems: Ewe body weight, reproductive efficiency, and longevity. Journal of Animal Science. 101. Article skac418. https://doi.org/10.1093/jas/skac418.

Impact of four ovine TMEM154 haplotypes on ewes during multiyear lentivirus exposure Reprint Icon - (Peer Reviewed Journal)
Freking, B.A., Murphy, T.W., Chitko-McKown, C.G., Workman, A.M., Heaton, M.P. 2022. Impact of four ovine TMEM154 haplotypes on ewes during multiyear lentivirus exposure. International Journal of Molecular Sciences. 23(23). Article 14966. https://doi.org/10.3390/ijms232314966.