2004 Annual Report 1.What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? What does it matter? Reproductive efficiency has a greater influence on the economic sustainability of commercial sheep production than does any other performance-related trait. This is because reproductive efficiency is a composite trait that affects the total weight of lambs weaned from a flock, and because commercial sheep are currently marketed on a live-weight basis. Indeed, flock reproductive efficiency is an integrated measure of age at puberty, capacity to produce and deliver adequate numbers of fertile spermatozoa, ovulation rate, ovum fertilization rate, embryo and fetal survival to parturition, prolificacy, milk yield of dams, postnatal survival to weaning, interval between pregnancies, reproductive lifespan, and ability to cope with a variety of environmental stressors. In addition, genotype and nutrient intake and utilization affect each of the traits comprising reproductive efficiency. Thus, genotypic changes that favor phenotypic traits, such as growth rate, muscling, and increased mature body size, must not be allowed to compromise reproductive efficiency. Current knowledge of each component of reproductive efficiency is not sufficient for the development of integrated production systems to optimize nutrient utilization, while allowing producers to respond effectively to market forces, such as consumer demands associated with meat quantity, quality, and flavor, with the confidence that reproductive efficiency will not be compromised. Thus, a thorough understanding of each component of reproductive efficiency is needed so that sheep can be selected to produce germplasm that will result in offspring appropriate for various management systems. In addition, cost effective methods are needed for efficient production and industry-wide delivery of superior sheep germplasm to ensure a high quality product for consumers. Therefore, this project is designed to improve economically important traits of sheep, determine how to mitigate the effects of stressors that divert nutrients away from reproduction and overall production, and maintain or improve reproductive efficiency. The specific objectives are to. 1)develop and validate nonsurgical, transcervical artificial insemination procedures for sheep,. 2)determine whether manipulating uterine immune functions will reduce the incidence of uterine bacterial contamination and prevent subsequent reductions in pregnancy and lambing rates,. 3)evaluate different biological types of sheep for reproductive efficiency, rate and efficiency of growth, carcass composition, meat quality, and mature size,. 4)determine whether strategic nutrient intervention will mitigate the negative effects of production stressors on growth, health, and reproductive processes and on skeletal muscle nutrient composition, and. 5)develop and validate methods for characterizing sexual performance of rams and reproductive efficiency of their daughters. Results from this project will allow us to improve economically important production traits of sheep without compromising reproductive efficiency. This project will address problems defined in the Reproductive Efficiency; Genetic Improvement; Nutrient Intake and Use; Growth and Development; and Product Quality components of the Action Plan for NP 101, Food Animal Production. Accomplishing the objectives for this project will allow us to. 1)produce and transfer to the industry recommendations and genetic selection tools that can be used to improve lifetime reproductive performance of ewes and rams, enhance the rate and efficiency of growth, and improve carcass composition and meat quality;. 2)transfer effective, nonsurgical artificial insemination procedures to the private sector;. 3)transfer an effective, nonantibiotic-based method for enhancing host immunity to reduce bacterial contamination in the uterus and improve reproductive success, and. 4)prescribe nutrient management strategies for enhancing sheep tolerance to stressors and optimizing production efficiencies. 2.List the milestones (indicators of progress) from your Project Plan. Year 1 (FY 2004) Further develop and validate nonsurgical, transcervical artificial insemination (TC-AI) procedures for sheep, and compare the efficacy of transcervical methods with established laparoscopic procedures. Determine whether exogenous prostaglandin F2alpha (PGF2alpha) induces uterine secretion of PGF2alpha, up-regulates uterine immune functions, and reduces the severity of uterine infections, even if progesterone is maintained at luteal-phase concentrations. Define selenium balance and tissue distribution in growing wethers that have been fed supranutritional amounts of selenium from an organically bound source. Determine whether exposure of rams to estrual ewes at an early age and then as adults will improve sexual behavior of the rams in serving capacity tests will be completed. Begin evaluating different biological types of sheep for reproductive efficiency, rate and efficiency of growth, carcass composition, meat quality, and mature size. Use quantitative genetic methods to identify physical and physiological criteria for enhancing reproductive efficiency and other economically important traits, including meat quality, quantity, and flavor. Year 2 (FY 2005) Establish the influence of time and dietary concentration of selenium on selenium distribution in growing wether lambs. Determine whether a ram's sexual behavior classification can be used to predict breeding efficiency in a competitive-mating environment. Begin developing a new white face composite terminal sire breed that will better enable sheep producers to meet target market specifications with commercial lambs, resulting in a more desirable end product that meets consumer demands without sacrificing reproductive efficiency. Year 3 (FY 2006) Determine whether exogenous PGF2alpha treatment will enhance uterine health and improve pregnancy and lambing rates. Determine the effects of uterine infection and nutrient stressors on nutrient balance and metabolism in splanchnic and hind limb tissues of growing ewe lambs. Complete experiment to determine whether exposure of adult rams to estrual ewes before serving capacity tests will provide more reliable serving capacity test scores and whether a single cohort serving capacity test will provide more reliable serving capacity test scores than the current individual tests. Complete experiment to determine whether sexual behavior classification based on serving capacity tests can be used to predict the breeding performance of rams in single-and multiple-sire breeding regimens. Determine whether calpastatin activity can be determined through an antemortem biopsy procedure and whether activity that is correlated with the traditional method of measuring activity in postmortem longissimus muscle. Determine whether acute antemortem management stress negatively affects quality and nutritive composition of skeletal muscle. Year 4 (FY 2007) Establish the amount of selenium and D-alpha-tocopherol needed to mitigate the negative effects of uterine infection. 3.Milestones: A. The milestones listed below were scheduled to be completed in Year 1. Because the scientist who was assigned to the quantitative genetics portion of this project resigned, the quantitative genetics research was halted until a new scientist can be recruited and hired to continue the research. Year 1 (FY 2004) Manuscript written, submitted to journal, and accepted for publication on experiment to further develop and validate nonsurgical, transcervical artificial insemination (TC-AI) procedures for sheep, and compare the efficacy of transcervical methods with established laparoscopic procedures. Experiment completed to determine whether exogenous PGF2alpha induces uterine secretion of PGF2alpha, up-regulates uterine immune functions, and reduces the severity of uterine infections, even if progesterone is maintained at luteal-phase concentrations. A manuscript for this study is in preparation. The time dependent distribution of selenium in growing wethers fed supranutritional Se from an organically bound source was established, and a manuscript is being prepared for review and subsequent submission to a peer reviewed journal. Experiment designed to determine whether exposure of rams to estrual ewes at an early age and then as adult rams will improve the sexual behavior of rams in serving capacity tests was completed. Experiment to determine whether a ram's sexual behavior classification can be used to predict breeding efficiency in a competitive-mating environment was completed. Evaluation of different biological types of sheep for reproductive efficiency, rate and efficiency of growth, carcass composition, meat quality, and mature size was initiated. However, the scientist who was assigned to this project resigned, and work was halted until a new scientist can be recruited and hired to continue the research. Experiment to use quantitative genetic methods to identify physical and physiological criteria for enhancing reproductive efficiency and other economically important traits, including meat quality, quantity, and flavor was initiated. However, the scientist who was assigned to this project resigned, and work was halted until a new scientist can be recruited and hired to continue the research. B. The milestones for Years 2, 3, and 4 are listed below. The project is scheduled to be completed at the end of Year 4, and a new project will be developed and evaluated through the OSQR process. Milestones for the quantitative genetics portion of this project were not included because there is no assurance that a quantitative geneticist can be recruited and hired in time to accomplish this portion of the project. Year 2 A manuscript describing an experiment to determine whether exogenous PGF2alpha induces uterine secretion of PGF2alpha, up-regulates uterine immune functions, and reduces the severity of uterine infections, even if progesterone is maintained at luteal-phase concentrations will be submitted to a scientific journal. An experiment will be initiated to determine whether exogenous PGF2alpha treatment will enhance uterine health and improve pregnancy and lambing rates. The influence of duration of selenium feeding and dietary concentration of selenium on selenium distribution in growing wether lambs will be determined and subsequently published in a peer review journal. This information will be used to establish nutrient management strategies using organically bound sources of selenium. Data from the experiment to determine whether a ram's sexual behavior classification can be used to predict breeding efficiency in a competitive-mating environment will be analyzed. Results of experiment to determine whether exposure of rams to estrual ewes at an early age and then as adult rams will improve the sexual behavior of rams in serving capacity tests will be completed, written and submitted to a scientific journal. Experiments to determine whether exposure of adult rams to estrual ewes before serving capacity tests will provide more reliable serving capacity test scores and to test whether a single cohort serving capacity test will provide reliable serving capacity test scores than the current individual tests will be completed. Year 3 An experiment will be continued from Year 2 to determine whether exogenous PGF2¿ treatment will enhance uterine health and improve pregnancy and lambing rates. The influence of uterine infections and nutrient stressors on nutrient balance and metabolism in splanchnic and hind limb tissues of ewe lambs will be quantified and subsequently published in a peer review journal. This information will be used to reveal the key selenium (and associated nutrients) taxing effects of pathogen stressors in growing ewes. Results of experiment to determine whether a ram's sexual behavior classification can be used to predict breeding efficiency in a competitive-mating environment will be written and submitted to a scientific journal. Experiment to determine whether ram sexual behavior classification based on serving capacity tests can be used to predict the breeding performance of rams in single-and multiple-sire breeding regimens will be completed. Year 4 An experiment will be completed to determine whether exogenous PGFalpha treatment will enhance uterine health and improve pregnancy and lambing rates. The data will be analyzed, and a manuscript will be written and submitted to a scientific journal. The amount of supranutritional selenium and D-alpha-tocopherol needed to mitigate the negative nutrient taxing effects of pathogen stressors will be established and subsequently published in a peer review journal. This information will be used to develop nutrient management plans that will mitigate the negative effects of pathogen stressors on reproductive and growth efficiencies, health, and meat quality. Results of experiment to determine whether ram sexual behavior classification based on serving capacity tests can be used to predict the breeding performance of rams in single-and multiple-sire breeding regimens will be written and submitted to a scientific journal. Data analyses will be completed for a study to determine whether a ram's sexual behavior classification can be used to predict breeding performance in a competitive-mating environment. Data analyses will be completed to determine whether exposure of rams to estrual ewes at an early age and then as adults will improve sexual behavior in serving capacity tests. Data from an experiment to determine whether a three-ram cohort serving capacity test can be used to predict breeding performance of rams in single and multiple sire pens will be analyzed and additional studies will be conducted to further develop and evaluate the three-ram cohort serving capacity test. 4.What were the most significant accomplishments this past year? A. Uterine infections, which can cause significant reductions in reproductive efficiency, are often more severe in first parity animals. Scientists at the U.S. Sheep Experiment Station, Dubois, Idaho, completed a study in FY 2004 to determine whether intrauterine inoculation of nulliparous ewes with Arcanobacterium pyogenes and Escherichia coli would produce an antibody response and enhance the ability of the uterus to manage the bacteria. The results of the study indicate that intrauterine bacterial inoculations evoked an antibody response and reduced the severity of the induced infections. This information could be used to develop a vaccine and vaccination strategy to reduce the incidence of uterine infections, and thus the use of antibiotics to treat them, in first parity animals. B. Other Significant Accomplishment(s), if any: Limited information is available describing the distribution of selenium in lambs consuming supranutritional selenium from organically bound sources. Scientists at the U.S. Sheep Experiment Station, Dubois, Idaho, fed growing wether lambs a diet containing supranutritional selenium in the form of high selenium grain to determine the influence of time and dietary selenium concentration on selenium status and distribution. Most organs and tissues of the body were saturated with selenium early in the study, but skeletal muscle increased in selenium concentration throughout the duration of the study. This study provides information that will be used to develop strategic nutrient management programs to enhance whole body selenium status and increase the nutritive value of sheep meat products. Because cervical anatomy limits the use of transcervical intrauterine artificial insemination (TC-AI) in sheep, scientists at the U.S. Sheep Experiment Station, Dubois, Idaho, have developed an instrument to cope atraumatically with the cervix. Thus, a series of experiments was conducted to determine whether this instrument affects sperm transport into the oviducts, which are the site of ovum fertilization, pregnancy rates, or lambing rate. Direct intrauterine deposition of spermatozoa, using a surgical procedure to bypass the cervix, with the new instrument improved pregnancy rate, but, even though the new instrument did not affect sperm transport into the oviducts after TC-AI, the transcervical procedure reduced pregnancy and lambing rates. The TC AI procedure with the new instrument has all but eliminated any visual evidence of cervical trauma during TC-AI, so additional research will be conducted to determine how cervical manipulation associated with the TC-AI procedure reduces pregnancy and lambing rates. Scientists at the U.S. Sheep Experiment Station, Dubois, Idaho, determined that high sexual performance rams bred and impregnated approximately 50% of the ewes in a competitive breeding regimen, compared with 30% for male-oriented rams and 24% for low sexual performance rams. These results indicate that, even though rams that are classified as male oriented and low sexual performers under defined conditions can sire lambs, they are not as effective as rams classified as high sexual performers. This is important because it indicates that using high sexual performance rams can improve flock reproductive performance. Because high sexual performance rams are easy to identify in sexual performance tests, studies are underway to develop and validate practical methods for quickly identifying high sexual performance rams. Scientists at the U.S. Sheep Experiment Station, Dubois, Idaho, determined that the endocrine responses to a defined stressor were similar and could not be used to differentiate among three sexual classifications of rams. This is important because alternative methods are needed to replace the laborious and time consuming individual ram serving capacity tests that are often used to classify rams according to their expected sexual performance at breeding. Concentrations of cortisol, luteinizing hormone, and testosterone responses were evaluated in sexually inactive rams and sexually active female-oriented and male-oriented rams before, during, and after administration of restraint stress. The rams of the different sexual classifications respond to restraint stress similarly requiring development of other methods to differentiate among the ram classifications. Reproductive efficiency has a greater influence on the economic sustainability of commercial sheep production than does any other performance-related trait.Scientists at the U.S. Sheep Experiment Station, Dubois, Idaho, determined that early exposure of 6 to 7-mo-old rams to estrual ewes improved their sexual performance scores more than did no exposure or late exposure as adult rams before sexual performance testing. This study indicates that a brief, 17 to 21-day, early exposure to estrual ewes is useful for reducing sexual behavior problems of rams. The practice should improve mating performance of young rams and pregnancy rates of ewes mated with young rams C. Significant Accomplishments/Activities that Support Special Target Populations: None. D. Progress Report: Data are needed to describe the influence of supranutritional inorganic and organically bound selenium on fetal development. In cooperation with Drs. J. Caton and L. Reynolds, North Dakota State University, Fargo (NFCA 58-5364-4-477N; Parent project: 5364-31000-006-00D), a study was initiated at the U.S. Sheep Experiment Station, Dubois, Idaho, to evaluate the effects of supranutritional selenium on rapidly proliferating tissues of nutrient restricted, pregnant ewe lambs and their offspring. Supranutritional selenium reduced placentome number and uterine, fetal, fetal membrane, and placental weights. This information will be used to determine the daily inorganic and organically bound selenium intake maximums for pregnant sheep. Information is needed to define the major nutrient taxing effects of sheep production stressors. In cooperation with Dr. C. Loest, New Mexico State University, Las Cruces (NFCA 58-5364-4-483N; Parent project: 5364-31000-006-00D), a study was initiated at the U.S. Sheep Experiment Station, Dubois, Idaho, to assess the affects of uterine infection stress and increased dietary methionine on nutrient flux across splanchnic tissues of ewe lambs. A graduate student from New Mexico State University is in residence at the U.S. Sheep Experiment Station and participating in the study, which will be the basis for her M.S. thesis. Information from this study will be used to describe the nutrient requirements of sheep with bacterial infections and develop strategic nutrient management plans to offset the negative taxing effects of pathogen stressors. 5.Describe the major accomplishments over the life of the project, including their predicted or actual impact. Intrauterine inoculations with bacteria, that are typically associated with spontaneous uterine infections, produce an antibody response that is associated with an enhanced ability of the uterus to manage the bacteria. This information could lead to the development of a vaccine and vaccination strategy to reduce the incidence of uterine infections and reduce the use of antibiotics to treat them. Information from determining how cervical manipulation associated with transcervical intrauterine artificial insemination in sheep reduces pregnancy and lambing rates could be used to eliminate the need to use surgical artificial insemination procedures for sheep and make artificial insemination more cost effective and practical for sheep producers. The time dependent distribution of selenium in growing wethers fed supranutritional Se from an organically bound source was established. This will provide guidance for using high selenium feed products to enhance selenium status and content of sheep meat products. Simple, cost effective methods for identifying high sexual performance rams should enable producers to eliminate rams that are less likely to sire lambs and improve overall reproductive performance of sheep. Practical management strategies for reducing the incidence of sexual behavior problems with rams would increase mating performance of young rams and pregnancy rates of ewes mated with young rams. 6.What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end-user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? Methods for transcervical artificial insemination for sheep have recently been transferred to sheep producers in Brazil and scientists in the United States. The time dependent distribution of selenium in growing wether lambs has been presented to university extension personal at scheduled conferences 7.List your most important publications in the popular press and presentations to organizations and articles written about your work. Invited symposium presentation at the 23rd Annual Meeting of the American Society of Reproductive Immunology in 2003 (Yale University, New Haven, Connecticut) titled "Role of progesterone and potential role of prostaglandins in modulating the uterine response to infectious bacteria in postpartum animals." Invited symposium presentation at the 15th International Congress on Animal Reproduction in 2004 (Porto Seguro, Brazil) titled "Steroidal regulation of uterine immune defenses." Seminar titled "Effect of dietary organically bound selenium and d-alpha-tocopherol acetate bolus on serum antioxidant status of transit stressed wether lambs" was presented at the American Society of Animal Scientists meeting (Phoenix, AZ). Seminar titled "Time dependent distribution of selenium in supranutritionally fed wether lambs" was presented at the Western Coordinating Committee-39 meeting (Reno, NV). Seminar titled "Current nutrition research at the U.S. Sheep Experiment Station" was presented to the American Sheep Industry Association (Dubois, ID). Review Publications Wulster-Radcliffe, M.C., Wang, S., Lewis, G.S. 2004. Transcervical artificial insemination in sheep: effects of a new transcervical artificial insemination instrument and traversing the cervix on pregnancy and lambing rates. Theriogenology. 62:990-1002. Herrmann, L.M., Hotzel, I., Cheevers, W.P., Pretty On Top, K., Lewis, G.S., Knowles, D.P. SEVEN NEW OVINE PROGRESSIVE PNEUMONIA VIRUS (OPPV) FIELD ISOLATES FROM DUBOIS IDAHO SHEEP COMPRISE PART OF OPPV CLADE II BASED ON SURFACE ENVELOPE GLYCOPROTEIN (SU) SEQUENCES. Virus Research. 2004. v. 102. p. 215-220. Ward, M.A., Caton, J.S., Taylor, J.B., Lawler, T.L., Hallford, D.M., Redmer, D.A., Reynolds, L.P. 2004. Effect of level and source of selenium on maternal and fetal metabolic hormones in pregnant yearling ewes. Proceedings of 55th Western Section of the American Society of Animal Science. p. 367. Soto-Navarro, S.A., Williams, G.J., Taylor, J.B., Finley, J.W., Caton, J.S.2003. Effects of selenium source of characteristics of selenium digestibility in finishing beef steers [abstract]. Journal of Animal Science. 81(Suppl.2):95. Roselli, C.E., Larkin, K., Resko, J.A., Stellflug, J.N., Stormshak, F. 2004. The volume of a sexually dimorphic nucleus in the ovine medial preoptic area/anterior hypothalamus varies with sexual partner preference. Endocrinology. 145:478-483. Schrunk, J.M., Stellflug, J.N., Roselli, C.E., Stormshak, F. 2004. Fetal exposure to an aromatase inhibitor alters secretion of luteinizing hormone in castratedpost-pubertal rams [abstract]. Biology of Reproduction. 71(1):220. Lewis, G.S. 2003. Steroidal regulation of uterine resistance to bacterial infection in livestock. Reproductive Biology and Endocrinology. 1:117. http://www.rbej.com/content/1/1/117. Lewis, G.S. 2004. Steroidal regulation of uterine immune defenses. Animal Reproduction Science. 82-83:281-294. Soto-Navarro, S.A., T.L. Lawler, J.B. Taylor, L.P. Reynolds, J.J. Reed, J.W. Finley, and J.S. Caton. 2004. Effect of high selenium wheat on visceral organ mass, and intestinal cellularity and vascularity in finishing beef steers. J.Anim. Sci. 82:1788-1792. Lawler, T.L., J.B. Taylor, d, J.W. Finley, and J.S. Caton. 2004. Effect of Supranutritional and Organically-bound Selenium on Perfomance, Carcass Characteristics, and Selenium Distribution in Finishing Steers. J.Anim. Sci. 82:1488-1493. Ward, M.A., Caton, J.S., Taylor, J.B., Reynolds, L.P, Redmer, D.A. 2004. Effect of level and source of seleniumon size of gravid uterine tissues [abstract]. Journal of the Society for Gynecologic Investigation. 2:216A.