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Murphy TW, Freking BA, Bennett GL. Comparison of three maternal composite sheep breeds managed under pasture lambing and purebred or terminal mating systems: ewe body weight, reproductive efficiency, and longevity. J Anim Sci 2022; 101:6960707. [PMID: 36566459 PMCID: PMC9904179 DOI: 10.1093/jas/skac418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 12/23/2022] [Indexed: 12/26/2022] Open
Abstract
Extensive sheep systems have lower inputs (e.g., feed, labor, infrastructure) but, generally, lower outputs per ewe than intensively managed flocks. Average ewe prolificacy is low (< 1.1 lambs per ewe) across the United States and traditional expectation is that costs required to support larger litters will not be recovered due to greater lamb mortality. The Composite-IV (C-IV) is a 50% Romanov, 25% Katahdin, and 25% White Dorper hair sheep developed and selected for enhanced reproductive efficiency at the U.S. Meat Animal Research Center. Objectives of the current study were to compare productivity of C-IV ewes (N = 404) to Katahdin (N = 342) and Polypay (N = 390), two popular maternal composite breeds, in a lower-input system. Experimental ewes were exposed to either rams of their own breed or Texel rams for the first time at 7 mo of age and remained in the same mating system for up to 4 yr. Ewes lambed on pasture from May to June and were expected to rear their lambs in the absence of supplemental feed and with minimal intervention. The ewe age × breed interaction effect impacted all annually recorded traits (P < 0.01) including number and total weight of lamb marketed at 25 wk per ewe exposed to mating (LS25 and LW25, respectively). Within all ages, LS25 of C-IV was greater (1.2 to 1.63 lambs; P < 0.01) than Katahdin (0.71 to 1.17 lambs) and Polypay (0.68 to 1.26 lambs) which were similar. At 1, 2, and 3-yr of age, C-IV ewes had, on average, 12 to 17 kg greater LW25 (P ≤ 0.01) than other breeds. Polypay LW25 was similar to Katahdin at 1 yr of age, but 8 to 13 kg greater (P < 0.01) at older ages. At 4 yr of age, LW25 was similar for C-IV and Polypay (63 and 62 kg, respectively). Overall, Texel mating improved LW25 by 3 kg compared to purebred mating (P < 0.01). Twin litters were most common within mature ewes (> 1 yr) of all breeds (52% to 65%); however, the proportion of triplet litters was numerically greater for C-IV (13%) than Katahdin (1%) or Polypay (4%). The frequency of mature ewes that gave birth to and reared twins (75% to 82%) was high for all breeds. Most triplet-bearing mature C-IV ewes reared twins (43%) though many reared triplets (39%). Ewe reproductive efficiency can be enhanced in lower-input systems by utilizing additive breed effects and heterosis in a complimentary crossbreeding program. More research is needed to identify indicator traits associated with lamb survival and to derive appropriate levels of prolificacy to fit specific management constraints.
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Affiliation(s)
| | - Brad A Freking
- USDA, ARS, Roman L. Hruska U.S. Meat Animal Research Center, Clay Center, NE 68933, USA
| | - Gary L Bennett
- USDA, ARS, Roman L. Hruska U.S. Meat Animal Research Center, Clay Center, NE 68933, USA
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Genetic diversity in 10 populations of domestic Turkeys by using microsatellites markers. Poult Sci 2022; 102:102311. [PMID: 36495620 PMCID: PMC9758563 DOI: 10.1016/j.psj.2022.102311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 09/28/2022] [Accepted: 10/31/2022] [Indexed: 11/06/2022] Open
Abstract
The domestic turkey is a native breed in danger of extinction due to the introduction of new breeds specializing in meat production and yield. Turkeys have lost some prominence in urban areas, and only certain breeds of turkeys are preserved in rural areas. Wild and domestic turkeys are different; rural or indigenous turkeys, with black plumage, were domesticated from Mexican turkeys and have been reproduced throughout Latin America. Some of them were taken to Europe in the 16th century and later arrived in North America, where they crossed with another wild species, from which the bronze turkey emerged: the ancestor of all commercial turkeys. The objective of the present work was to evaluate the genetic diversity in 10 populations of domestic turkeys worldwide by using breeds from Europe: Spain and Italy; America: Mexico, United States and Brazil; and the Near East: Iran and Egypt. A total of 522 blood samples of both sexes were collected from domestic turkey populations. Thirty-four microsatellites were used to obtain genetic parameters, and genetic diversity was evaluated. All microsatellites used were polymorphic, and a total of 427 alleles were detected across the 34 markers investigated. In this study, a mean number of 13.44 alleles was found. The four most diverse breeds were from the Andalusia, Mexico, United States, and wild populations, which had the highest mean heterozygosity expected (0.619, 0.612, 0.650, and 0.773) and heterozygosity observed (0.422, 0.521, 0.429, and 0.627), respectively. The MNT348 marker deviated from the HWE in all populations. Our study has shown that the populations close to the species origin are more diverse than those resulting from posterior expansions. Mexican birds were the most diverse, followed by the Spanish populations because Spain imported a large number of turkeys coming from America. Such information can be complementary to other genotypic data required to validate the evolutionary relationships among turkey populations.
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Tadesse D, Patra AK, Puchala R, Goetsch AL. Effects of High Heat Load Conditions on Blood Constituent Concentrations in Dorper, Katahdin, and St. Croix Sheep from Different Regions of the USA. Animals (Basel) 2022; 12:ani12172273. [PMID: 36077993 PMCID: PMC9454635 DOI: 10.3390/ani12172273] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Revised: 08/29/2022] [Accepted: 08/30/2022] [Indexed: 11/16/2022] Open
Abstract
Forty-six Dorper (DOR), 46 Katahdin (KAT), and 43 St. Croix (STC) female sheep (initial body weight of 58, 59, and 46 kg, respectively, SEM = 1.75; 3.3 ± 0.18 years of age, 2.6−3.7), derived from 45 commercial farms in four regions of the USA (Midwest, Northwest, Southeast, and central Texas), were used to evaluate responses in blood constituent concentrations to increasing heat load index (HLI) conditions. There were four sequential 2 weeks periods with target HLI during day/nighttime of 70/70 (thermoneutral zone conditions), 85/70, 90/77, and 95/81 in period 1, 2, 3 and 4, respectively. A 50% concentrate pelletized diet was fed at 53.3 g dry matter/kg body weight0.75. The analysis of most constituents was for samples collected on the last day of the second week of each period at 13:00 h; samples for cortisol, thyroxine, and heat shock protein were collected in week 2 and 8. Previously, it was noted that resilience to high HLI conditions was greatest for STC, lowest for DOR, and intermediate for KAT. There were few effects of region. Other than hemoglobin concentration, there were no interactions between breed and period. Blood oxygen concentration was greatest (p < 0.05) among breeds for STC (5.07, 5.20, and 5.53 mmol/L for DOR, KAT, and STC, respectively; SEM = 0.114) and differed among periods (4.92, 5.26, 5.36, and 5.52 mmol/L for period 1, 2, 3, and 4, respectively; SEM = 0.093). There were breed differences (i.e., main effects; p < 0.05) in glucose (50.0, 52.6, and 52.1 mg/dL; SEM = 0.76), urea nitrogen (17.2, 17.3, and 19.4 mg/dL; SEM = 0.33), creatinine (0.991, 0.862, and 0.802 mg/dL; SEM = 0.0151), total protein (6.50, 6.68, and 6.95 g/l; SEM = 0.017), triglycerides (28.4, 29.1, and 23.5 mg/dL; SEM = 0.87), and cortisol (6.30, 8.79, and 6.22 ng/mL for DOR, KAT, and STC, respectively; SEM = 0.596). Differences among periods (p < 0.05) were observed for lactate (27.9, 25.3, 27.8, and 24.0 mg/dL; SEM = 0.99), creatinine (0.839, 0.913, 0.871, and 0.917 mg/dL; SEM = 0.0128), total protein (6.94, 6.66, 6.60, and 6.65 g/l; SEM = 0.094), and cholesterol (60.2, 56.5, 58.3, and 57.6 mg/dL for period 1, 2, 3, and 4, respectively; SEM = 1.26). In addition, the concentration of cortisol (7.62 and 6.59 ng/mL; SEM = 0.404), thyroxine (5.83 and 5.00 µg/dL; SEM = 0.140), and heat shock protein (136 and 146 ng/mL for week 2 and 8, respectively; SEM = 4.0) differed between weeks (p < 0.05). In conclusion, the lack of interaction between breed and period with different HLI conditions suggests that levels of these blood constituents were not highly related to resilience to high HLI.
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Affiliation(s)
- Dereje Tadesse
- American Institute for Goat Research, Langston University, Langston, OK 73050, USA
- Department of Animal Sciences, Debre Berhan University, Debre Berhan P.O. Box 445, Ethiopia
| | - Amlan Kumar Patra
- Department of Animal Nutrition, West Bengal University of Animal and Fishery Sciences, Kolkata 700037, India
| | - Ryszard Puchala
- American Institute for Goat Research, Langston University, Langston, OK 73050, USA
| | - Arthur Louis Goetsch
- American Institute for Goat Research, Langston University, Langston, OK 73050, USA
- Correspondence:
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Tadesse D, Puchala R, Goetsch AL. Effects of restricted feed intake on blood constituent concentrations in Dorper, Katahdin, and St. Croix sheep from different regions of the USA. Vet Anim Sci 2021; 14:100211. [PMID: 34703948 PMCID: PMC8526753 DOI: 10.1016/j.vas.2021.100211] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 10/06/2021] [Accepted: 10/07/2021] [Indexed: 11/29/2022] Open
Abstract
Forty-six Dorper, 47 Katahdin, and 41 St. Croix female sheep (initial BW = 62, 62, and 51 kg, respectively, SEM = 1.43; 3.8 ± 0.18 yr) from farms in Midwest, Northwest, Southeast, and central Texas regions of the USA were used to evaluate effects of feed restriction on blood constituent levels. The amount of feed offered varied in the first 4 wk to achieve stable BW, and that in wk 5–10 was 55% of intake in wk 3–4. Blood was sampled at the end of wk 3, 4, 6, 8, and 10. There were relatively few effects and interactions involving region and no breed × time interactions. Breed affected the concentration of a small number of constituents, including urea N (14.0, 13.7, and 15.4 mg/dl; SEM = 0.31) and creatinine (0.945, 0.836, and 0.809 mg/dl for Dorper, Katahdin, and St. Croix, respectively; SEM = 0.0253). Also, the concentration of triglycerides in wk 4 and 10 was lowest for St. Croix (29.8, 29.5, and 26.7 mg/dl for Dorper, Katahdin, and St. Croix, respectively; SEM = 0.88). There was a trend for a difference (P = 0.051) between wk 4 and 10 in the glucose concentration (51.9 and 54.2 mg/dl; SEM = 0.90), and there were differences (P < 0.05) in lactate (23.9 and 20.3 mg/dl; SEM = 0.89), urea N (16.4 and 13.0 mg/dl; SEM = 0.25), creatinine (0.808 and 0.919 mg/dl; SEM = 0.0165), triglycerides (31.8 and 25.5 mg/dl; SEM = 0.63), and cholesterol (67.5 and 74.7 mg/dl, respectively; SEM = 1.66). In conclusion, similar responses in blood constituent levels of different hair sheep breeds to feed restriction is in accordance with comparable effects on the maintenance energy requirement.
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Affiliation(s)
- D Tadesse
- American Institute for Goat Research, Langston University, Langston, OK, USA.,College of Agriculture, Debre Berhan University, Debre Berhan, Ethiopia
| | - R Puchala
- American Institute for Goat Research, Langston University, Langston, OK, USA
| | - A L Goetsch
- American Institute for Goat Research, Langston University, Langston, OK, USA
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Thorne JW, Murdoch BM, Freking BA, Redden RR, Murphy TW, Taylor JB, Blackburn HD. Evolution of the sheep industry and genetic research in the United States: opportunities for convergence in the twenty-first century. Anim Genet 2021; 52:395-408. [PMID: 33955573 PMCID: PMC8360125 DOI: 10.1111/age.13067] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/02/2021] [Indexed: 12/14/2022]
Abstract
The continuous development and application of technology for genetic improvement is a key element for advancing sheep production in the United States. The US sheep industry has contracted over time but appears to be at a juncture where a greater utilization of technology can facilitate industry expansion to new markets and address inefficiencies in traditional production practices. Significant transformations include the increased value of lamb in relation to wool, and a downtrend in large-scale operations but a simultaneous rise in small flocks. Additionally, popularity of hair breeds not requiring shearing has surged, particularly in semi-arid and subtropical US environments. A variety of domestically developed composite breeds and newly established technological approaches are now widely available for the sheep industry to use as it navigates these ongoing transformations. These genetic resources can also address long-targeted areas of improvement such as growth, reproduction and parasite resistance. Moderate progress in production efficiency has been achieved by producers who have employed estimated breeding values, but widespread adoption of this technology has been limited. Genomic marker panels have recently shown promise for reducing disease susceptibility, identifying parentage and providing a foundation for marker-assisted selection. As the ovine genome is further explored and genomic assemblies are improved, the sheep research community in the USA can capitalize on new-found information to develop and apply genetic technologies to improve the production efficiency and profitability of the sheep industry.
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Affiliation(s)
- J. W. Thorne
- Texas A&M AgriLife ExtensionTexas A&M UniversitySan AngeloTX76901USA
- Department of Animal, Veterinary and Food ScienceUniversity of IdahoMoscowID83844USA
| | - B. M. Murdoch
- Department of Animal, Veterinary and Food ScienceUniversity of IdahoMoscowID83844USA
| | - B. A. Freking
- United States Meat Animal Research CenterUnited States Department of Agriculture, Agricultural Research ServiceClay CenterNE68933‐0166USA
| | - R. R. Redden
- Texas A&M AgriLife ExtensionTexas A&M UniversitySan AngeloTX76901USA
| | - T. W. Murphy
- United States Meat Animal Research CenterUnited States Department of Agriculture, Agricultural Research ServiceClay CenterNE68933‐0166USA
| | - J. B. Taylor
- United States Sheep Experiment StationUnited States Department of Agriculture, Agricultural Research ServiceDuboisID83423USA
| | - H. D. Blackburn
- National Animal Germplasm ProgramUnited States Department of Agriculture, Agricultural Research ServiceFort CollinsCO80521USA
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Canales Vergara AM, Landi V, Delgado Bermejo JV, Martínez AM, Cervantes Acosta P, Pons Barros A, Bigi D, Sponenberg P, Helal M, Banabazi MH, Camacho Vallejo ME. Design and development of a multiplex microsatellite panel for the genetic characterisation and diversity assessment of domestic turkey ( Meleagris gallopavo gallopavo). ITALIAN JOURNAL OF ANIMAL SCIENCE 2020. [DOI: 10.1080/1828051x.2020.1745695] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
| | - Vincenzo Landi
- Animal Breeding Consulting S.L. Parque Científico Tecnológico de Córdoba c/Astrónoma Cecilia Payne, Córdoba, España
| | | | - Amparo Martínez Martínez
- Department of Genetics, Faculty of Veterinary Sciences, University of Córdoba, Cordoba, Spain
- Animal Breeding Consulting S.L. Parque Científico Tecnológico de Córdoba c/Astrónoma Cecilia Payne, Córdoba, España
| | | | | | - Daniele Bigi
- Department of Agricultural and Food Sciences, Università di Bologna, Bologna, Italy
| | - Phillip Sponenberg
- Department of Biomedical Sciences & Pathobiology, Virginia-Maryland College of Veterinary Medicine, Blacksburg, VA, USA
| | - Mostafa Helal
- Department of Animal Production, Cairo University, Giza, Egypt
| | - Mohammad Hossein Banabazi
- Department of Biotechnology, Animal Science Research Institute of IRAN (ASRI), Agricultural Research, Education & Extension Organization (AREEO), Karaj, Iran
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Occurrence of Gastrointestinal Parasites in Small Ruminants in the Central Part of Myanmar. J Parasitol Res 2020; 2020:8826327. [PMID: 33294216 PMCID: PMC7714589 DOI: 10.1155/2020/8826327] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 10/29/2020] [Accepted: 11/13/2020] [Indexed: 11/21/2022] Open
Abstract
Gastrointestinal parasite infection in small ruminants remains one of the major economic losses caused by reduced productivity. A total of 380 faecal samples were taken from 280 sheeps in Magway and Pwintbyu Townships and 100 goats in Natmauk Township, Myanmar. Faecal flotation and sedimentation methods were carried out to detect the presence of parasitic infections. Faecal egg and oocyst counts were carried out using the McMaster technique. The overall occurrence of gastrointestinal parasites in small ruminants was 98.4% (374/380). The occurrence of gastrointestinal parasites in sheep (99.3%) was higher than that in goats (96%). The highest occurrence was found in Eimeria spp. (96%), followed by Trichostrongyle (77.1%), Trichuris spp. (35%), and Moniezia expansa (14%). The mixed infection rate was 84.8% (317/374), while a single infection was 15.2% (57/374). The mean eggs per gram (EPG) and oocysts per gram (OPG) of faeces were ranged from 50 to 600 and 50 to 29,800, respectively. Among the 4 nucleotide sequences isolated, one sequence was 94.10-94.47% similarity with Trichostrongylus colubriformis, reported from Laos, and three sequences showed 96.64-99.46% identity with Haemonchus contortus from Laos, China, India, and Mongolia. As gastrointestinal parasite infection in small ruminants was relatively high in the study area, the development of appropriate treatment and control measures should be provided to reduce production losses.
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Purdy PH, Spiller SF, McGuire E, McGuire K, Koepke K, Lake S, Blackburn HD. Critical factors for non-surgical artificial insemination in sheep. Small Rumin Res 2020. [DOI: 10.1016/j.smallrumres.2020.106179] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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9
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Davenport KM, Hiemke C, McKay SD, Thorne JW, Lewis RM, Taylor T, Murdoch BM. Genetic structure and admixture in sheep from terminal breeds in the United States. Anim Genet 2020; 51:284-291. [PMID: 31970815 PMCID: PMC7065203 DOI: 10.1111/age.12905] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/12/2019] [Indexed: 11/29/2022]
Abstract
Selection for performance in diverse production settings has resulted in variation across sheep breeds worldwide. Although sheep are an important species to the United States, the current genetic relationship among many terminal sire breeds is not well characterized. Suffolk, Hampshire, Shropshire and Oxford (terminal) and Rambouillet (dual purpose) sheep (n = 248) sampled from different flocks were genotyped using the Applied Biosystems Axiom Ovine Genotyping Array (50K), and additional Shropshire sheep (n = 26) using the Illumina Ovine SNP50 BeadChip. Relationships were investigated by calculating observed heterozygosity, inbreeding coefficients, eigenvalues, pairwise Wright’s FST estimates and an identity by state matrix. The mean observed heterozygosity for each breed ranged from 0.30 to 0.35 and was consistent with data reported in other US and Australian sheep. Suffolk from two different regions of the United States (Midwest and West) clustered separately in eigenvalue plots and the rectangular cladogram. Further, divergence was detected between Suffolk from different regions with Wright’s FST estimate. Shropshire animals showed the greatest divergence from other terminal breeds in this study. Admixture between breeds was examined using admixture, and based on cross‐validation estimates, the best fit number of populations (clusters) was K = 6. The greatest admixture was observed within Hampshire, Suffolk, and Shropshire breeds. When plotting eigenvalues, US terminal breeds clustered separately in comparison with sheep from other locations of the world. Understanding the genetic relationships between terminal sire breeds in sheep will inform us about the potential applicability of markers derived in one breed to other breeds based on relatedness.
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Affiliation(s)
- K M Davenport
- Department of Animal and Veterinary Science, University of Idaho, Moscow, ID, 83844, USA
| | - C Hiemke
- Niman Ranch and Mapleton Mynd Shropshires, Stoughton, MA, 53589, USA
| | - S D McKay
- Department of Animal and Veterinary Sciences, University of Vermont, Burlington, VT, 05405, USA
| | - J W Thorne
- Department of Animal and Veterinary Science, University of Idaho, Moscow, ID, 83844, USA.,Texas A&M AgriLife Extension, San Angelo, TX, 76901, USA
| | - R M Lewis
- Department of Animal Science, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA
| | - T Taylor
- Department of Animal Science, Arlington Research Station, University of Wisconsin-Madison, Arlington, WI, 53911, USA
| | - B M Murdoch
- Department of Animal and Veterinary Science, University of Idaho, Moscow, ID, 83844, USA
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Conservation and Utilization of Livestock Genetic Diversity in the United States of America through Gene Banking. DIVERSITY 2019. [DOI: 10.3390/d11120244] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A germplasm collection curated by the United States Department of Agriculture (USDA), Agricultural Research Service (ARS), National Animal Germplasm Program contains of over one million samples from over 55,000 animals, representing 165 livestock and poultry breeds. The collection was developed to provide genetic conservation and security for the U.S. livestock sector. Samples in the collection span 60 years, suggesting a wide range of genetic diversity and genetic change is represented for rare and major breeds. Classifying breeds into four groups based upon registration or census estimates of population size of < 1000, < 5000, < 20,000, and > 20,000 indicated that 50% of the collection is comprised of rare breeds in the < 1000 category. As anticipated, collections for breeds in the < 20,000 and > 20,000 are more complete (86% and 98%, respectively) based upon an index combining the number of germplasm samples and the number of animals. For the rarest breeds (< 1000), collection completeness was 45%. Samples from over 6000 animals in the collection have been used for adding diversity to breeds, genomic evaluation, reconstituting populations, or various research projects. Several aspects of collecting germplasm samples from rare breeds are discussed. In addition, approaches that could be used to enhance the status of rare breeds via the repository use are presented. However, given the array of obstacles confronting rare breeds, the gene bank may be the most secure prospect for the long-term conservation of rare breed genetics.
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Spangler GL, Rosen BD, Ilori MB, Hanotte O, Kim ES, Sonstegard TS, Burke JM, Morgan JLM, Notter DR, Van Tassell CP. Whole genome structural analysis of Caribbean hair sheep reveals quantitative link to West African ancestry. PLoS One 2017; 12:e0179021. [PMID: 28662044 PMCID: PMC5490989 DOI: 10.1371/journal.pone.0179021] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 05/23/2017] [Indexed: 01/05/2023] Open
Abstract
Hair sheep of Caribbean origin have become an important part of the U.S. sheep industry. Their lack of wool eliminates a number of health concerns and drastically reduces the cost of production. More importantly, Caribbean hair sheep demonstrate robust production performance even in the presence of drug-resistant gastrointestinal nematodes, a rising concern to the industry. Despite the growing importance of hair sheep in the Americas their genetic origins have remained speculative. Prior to this report no genetic studies were able to identify a unique geographical origin of hair sheep in the New World. Our study clarifies the African and European ancestry of Caribbean hair sheep. Whole-genome structural analysis was conducted on four established breeds of hair sheep from the Caribbean region. Using breeds representing Africa and Europe we establish an objective measure indicating Caribbean hair sheep are derived from Iberian and West African origins. Caribbean hair sheep result from West African introgression into established ecotypes of Iberian descent. Genotypes from 47,750 autosomal single nucleotide polymorphism markers scored in 290 animals were used to characterize the population structure of the St. Croix, Barbados Blackbelly, Morada Nova, and Santa Ines. Principal components, admixture, and phylogenetic analyses results correlate with historical patterns of colonization and trade. These patterns support co-migration of these sheep with humans.
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Affiliation(s)
- Gordon L. Spangler
- Animal Genomics and Improvement Laboratory, Agricultural Research Service, United States Department of Agriculture, Beltsville, Maryland, United States of America
| | - Benjamin D. Rosen
- Animal Genomics and Improvement Laboratory, Agricultural Research Service, United States Department of Agriculture, Beltsville, Maryland, United States of America
| | | | - Olivier Hanotte
- School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Eui-Soo Kim
- Acceligen of Recombinetics Incorporated, Saint Paul, Minnesota, United States of America
| | - Tad S. Sonstegard
- Acceligen of Recombinetics Incorporated, Saint Paul, Minnesota, United States of America
| | - Joan M. Burke
- Dale Bumpers Small Farms Research Station, Agricultural Research Service, United States Department of Agriculture, Booneville, Arkansas, United States of America
| | - James L. M. Morgan
- Katahdin Hair Sheep International, Fayetteville, Arkansas, United States of America
| | - David R. Notter
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg, Virginia, United States of America
| | - Curtis P. Van Tassell
- Animal Genomics and Improvement Laboratory, Agricultural Research Service, United States Department of Agriculture, Beltsville, Maryland, United States of America
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Host-parasite ecology of keds (Melophagus ovinus (L.)) relative to sheep breed and age on Wyoming rangeland. Livest Sci 2016. [DOI: 10.1016/j.livsci.2016.05.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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13
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Acharya M, Burke JM, Coffey KP, Kegley EB, Miller JE, Smyth E, Welborn MG, Terrill TH, Mosjidis JA, Rosenkrans C. Changes in concentrations of trace minerals in lambs fed sericea lespedeza leaf meal pellets with or without dietary sodium molybdate12. J Anim Sci 2016; 94:1592-9. [DOI: 10.2527/jas.2015-9910] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- M. Acharya
- Department of Animal Science, University of Arkansas, Fayetteville 72701
| | - J. M. Burke
- USDA, ARS, Dale Bumpers Small Farms Research Center, Booneville, AR 72927
| | - K. P. Coffey
- Department of Animal Science, University of Arkansas, Fayetteville 72701
| | - E. B. Kegley
- Department of Animal Science, University of Arkansas, Fayetteville 72701
| | - J. E. Miller
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge 70803
| | - E. Smyth
- Department of Animal Science, University of Arkansas, Fayetteville 72701
- USDA, ARS, Dale Bumpers Small Farms Research Center, Booneville, AR 72927
| | - M. G. Welborn
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge 70803
| | - T. H. Terrill
- Agricultural Research Station, Fort Valley State University, Fort Valley, GA 31030
| | - J. A. Mosjidis
- Department of Crop, Soil and Environmental Sciences, Auburn University, Auburn 36849
| | - C. Rosenkrans
- Department of Animal Science, University of Arkansas, Fayetteville 72701
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E GX, Zhong T, Ma YH, Gao HJ, He JN, Liu N, Zhao YJ, Zhang JH, Huang YF. Conservation genetics in Chinese sheep: diversity of fourteen indigenous sheep (Ovis aries) using microsatellite markers. Ecol Evol 2016; 6:810-7. [PMID: 26865968 PMCID: PMC4739567 DOI: 10.1002/ece3.1891] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 11/13/2015] [Accepted: 11/23/2015] [Indexed: 11/10/2022] Open
Abstract
The domestic sheep (Ovis aries) has been an economically and culturally important farm animal species since its domestication around the world. A wide array of sheep breeds with abundant phenotypic diversity exists including domestication and selection as well as the indigenous breeds may harbor specific features as a result of adaptation to their environment. The objective of this study was to investigate the population structure of indigenous sheep in a large geographic location of the Chinese mainland. Six microsatellites were genotyped for 611 individuals from 14 populations. The mean number of alleles (±SD) ranged from 7.00 ± 3.69 in Gangba sheep to 10.50 ± 4.23 in Tibetan sheep. The observed heterozygote frequency (±SD) within a population ranged from 0.58 ± 0.03 in Gangba sheep to 0.71 ± 0.03 in Zazakh sheep and Minxian black fur sheep. In addition, there was a low pairwise difference among the Minxian black fur sheep, Mongolian sheep, Gansu alpine merino, and Lanzhou fat-tailed sheep. Bayesian analysis with the program STRUCTURE showed support for 3 clusters, revealing a vague genetic clustering pattern with geographic location. The results of the current study inferred high genetic diversity within these native sheep in the Chinese mainland.
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Affiliation(s)
- Guang-Xin E
- College of Animal Science and Technology Chongqing Key Laboratory of Forage & Herbivore Chongqing Engineering Research Centre for Herbivores Resource Protection and Utilization Southwest University Chongqing 400716 China
| | - Tao Zhong
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan province Sichuan Agricultural University Chengdu Sichuan 625014 China
| | - Yue-Hui Ma
- Institute of Animal Science Chinese Academy of Agricultural Sciences (CAAS) Beijing 100193 China
| | - Hui-Jiang Gao
- Institute of Animal Science Chinese Academy of Agricultural Sciences (CAAS) Beijing 100193 China
| | - Jian-Ning He
- College of Animal Science and Technology Qingdao Agricultural University Qingdao 266109 China
| | - Nan Liu
- College of Animal Science and Technology Qingdao Agricultural University Qingdao 266109 China
| | - Yong-Ju Zhao
- College of Animal Science and Technology Chongqing Key Laboratory of Forage & Herbivore Chongqing Engineering Research Centre for Herbivores Resource Protection and Utilization Southwest University Chongqing 400716 China
| | - Jia-Hua Zhang
- College of Animal Science and Technology Chongqing Key Laboratory of Forage & Herbivore Chongqing Engineering Research Centre for Herbivores Resource Protection and Utilization Southwest University Chongqing 400716 China
| | - Yong-Fu Huang
- College of Animal Science and Technology Chongqing Key Laboratory of Forage & Herbivore Chongqing Engineering Research Centre for Herbivores Resource Protection and Utilization Southwest University Chongqing 400716 China
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Purdy PH, Wilson CS, Spiller SF, Blackburn HD. Biobanking genetic resources: challenges and implementation at the USDA National Animal Germplasm Program. Reprod Fertil Dev 2015; 28:RD15399. [PMID: 26678540 DOI: 10.1071/rd15399] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 11/24/2015] [Indexed: 11/23/2022] Open
Abstract
There is adequate infrastructure in the US to identify and acquire germplasm from the major beef and dairy cattle and swine breeds. However, when we venture outside these species, the same tasks become more difficult because of a lack of breed associations, databases that include genotypic and phenotypic data and low numbers of animals. Furthermore, acquisition of germplasm from non-cattle and non-swine species can be difficult because these animals are often not located near the National Animal Germplasm Program, which makes collection and preservation of the samples in a timely manner that much more complicated. This problem is compounded because not all preservation protocols are optimised for field collection conditions or for all types of germplasm. Since 1999, the USDA National Animal Germplasm Program has worked to overcome these obstacles by developing policies, procedures and techniques in order to create a germplasm repository for all agricultural species (wild and domesticated) in the US. Herein, we describe these activities and illustrate them via a case study on how our efforts collecting Navajo-Churro sheep have created a secure backup of germplasm and how we specifically overcome these issues as they relate to rare and minor breeds of agricultural species.
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Casellas J, Piedrafita J. Accuracy and expected genetic gain under genetic or genomic evaluation in sheep flocks with different amounts of pedigree, genomic and phenotypic data. Livest Sci 2015. [DOI: 10.1016/j.livsci.2015.10.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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Al-Mamun HA, Clark SA, Kwan P, Gondro C. Genome-wide linkage disequilibrium and genetic diversity in five populations of Australian domestic sheep. Genet Sel Evol 2015; 47:90. [PMID: 26602211 PMCID: PMC4659207 DOI: 10.1186/s12711-015-0169-6] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 11/02/2015] [Indexed: 01/23/2023] Open
Abstract
Background Knowledge of the genetic structure and overall diversity of livestock species is important to maximise the potential of genome-wide association studies and genomic prediction. Commonly used measures such as linkage disequilibrium (LD), effective population size (Ne), heterozygosity, fixation index (FST) and runs of homozygosity (ROH) are widely used and help to improve our knowledge about genetic diversity in animal populations. The development of high-density single nucleotide polymorphism (SNP) arrays and the subsequent genotyping of large numbers of animals have greatly increased the accuracy of these population-based estimates. Methods In this study, we used the Illumina OvineSNP50 BeadChip array to estimate and compare LD (measured by r2 and D′), Ne, heterozygosity, FST and ROH in five Australian sheep populations: three pure breeds, i.e., Merino (MER), Border Leicester (BL), Poll Dorset (PD) and two crossbred populations i.e. F1 crosses of Merino and Border Leicester (MxB) and MxB crossed to Poll Dorset (MxBxP). Results Compared to other livestock species, the sheep populations that were analysed in this study had low levels of LD and high levels of genetic diversity. The rate of LD decay was greater in Merino than in the other pure breeds. Over short distances (<10 kb), the levels of LD were higher in BL and PD than in MER. Similarly, BL and PD had comparatively smaller Ne than MER. Observed heterozygosity in the pure breeds ranged from 0.3 in BL to 0.38 in MER. Genetic distances between breeds were modest compared to other livestock species (highest FST = 0.063) but the genetic diversity within breeds was high. Based on ROH, two chromosomal regions showed evidence of strong recent selection. Conclusions This study shows that there is a large range of genome diversity in Australian sheep breeds, especially in Merino sheep. The observed range of diversity will influence the design of genome-wide association studies and the results that can be obtained from them. This knowledge will also be useful to design reference populations for genomic prediction of breeding values in sheep. Electronic supplementary material The online version of this article (doi:10.1186/s12711-015-0169-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | - Samuel A Clark
- School of Environmental and Rural Science, University of New England, Armidale, NSW, 2351, Australia.
| | - Paul Kwan
- School of Science and Technology, University of New England, Armidale, NSW, 2351, Australia.
| | - Cedric Gondro
- School of Environmental and Rural Science, University of New England, Armidale, NSW, 2351, Australia.
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18
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Genetic relationship and admixture in four Tunisian sheep breeds revealed by microsatellite markers. Small Rumin Res 2015. [DOI: 10.1016/j.smallrumres.2015.08.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Leroy G, Danchin-Burge C, Palhière I, SanCristobal M, Nédélec Y, Verrier E, Rognon X. How do introgression events shape the partitioning of diversity among breeds: a case study in sheep. Genet Sel Evol 2015; 47:48. [PMID: 26080856 PMCID: PMC4470023 DOI: 10.1186/s12711-015-0131-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 06/01/2015] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND From domestication to the current pattern of differentiation, domestic species have been influenced by reticulate evolution with multiple events of migration, introgression, and isolation; this has resulted in a very large number of breeds. In order to manage these breeds and their genetic diversity, one must know the current genetic structure of the populations and the relationships among these. This paper presents the results of a genetic diversity analysis on an almost exhaustive sample of the sheep breeds reared in France. Molecular characterization was performed with a set of 21 microsatellite markers on a collection of 49 breeds that include five breed types: meat, hardy meat, dairy, high prolificacy and patrimonial breeds. RESULTS Values of expected heterozygosity ranged from 0.48 to 0.76 depending on the breed, with specialized meat breeds exhibiting the lowest values. Neighbor-Net, multidimensional analysis or clustering approaches revealed a clear differentiation of the meat breeds compared to the other breed types. Moreover, the group that clustered meat breeds included all the breeds that originated from the United Kingdom (UK) and those that originated from crossbreeding between UK breeds and French local breeds. We also highlighted old genetic introgression events that were related to the diffusion of Merino rams to improve wool production. As a result of these introgression events, especially that regarding the UK breeds, the breeds that were clustered in the 'meat type cluster' exhibited the lowest contribution to total diversity. That means that similar allelic combinations could be observed in different breeds of this group. CONCLUSIONS The genetic differentiation pattern of the sheep breeds reared in France results from a combination of factors, i.e. geographical origin, historic gene flow, and breed use. The Merino influence is weaker than that of UK breeds, which is consistent with how sheep use changed radically at the end of 19(th) century when wool-producing animals (Merino-like) were replaced by meat-producing breeds. These results are highly relevant to monitor and manage the genetic diversity of sheep and can be used to set priorities in conservation programs when needed.
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Affiliation(s)
- Grégoire Leroy
- AgroParisTech, UMR1313 Génétique Animale et Biologie Intégrative, F-75231, Paris 05, France. .,INRA, UMR1313 Génétique Animale et Biologie Intégrative, F-78352, Jouy-en-Josas, France.
| | | | - Isabelle Palhière
- INRA, UMR1388 Génétique, Physiologie et Systèmes d'Élevage, F-31326, Castanet-Tolosan, France. .,Université de Toulouse INPT ENVT, UMR1388 Génétique, Physiologie et Systèmes d'Élevage, F-31076, Toulouse, France. .,Université de Toulouse INPT ENSAT, UMR1388 Génétique, Physiologie et Systèmes d'Élevage, F-31326, Castanet-Tolosan, France.
| | - Magali SanCristobal
- INRA, UMR1388 Génétique, Physiologie et Systèmes d'Élevage, F-31326, Castanet-Tolosan, France. .,Université de Toulouse INPT ENVT, UMR1388 Génétique, Physiologie et Systèmes d'Élevage, F-31076, Toulouse, France. .,Université de Toulouse INPT ENSAT, UMR1388 Génétique, Physiologie et Systèmes d'Élevage, F-31326, Castanet-Tolosan, France.
| | - Yann Nédélec
- AgroParisTech, UMR1313 Génétique Animale et Biologie Intégrative, F-75231, Paris 05, France. .,INRA, UMR1313 Génétique Animale et Biologie Intégrative, F-78352, Jouy-en-Josas, France.
| | - Etienne Verrier
- AgroParisTech, UMR1313 Génétique Animale et Biologie Intégrative, F-75231, Paris 05, France. .,INRA, UMR1313 Génétique Animale et Biologie Intégrative, F-78352, Jouy-en-Josas, France.
| | - Xavier Rognon
- AgroParisTech, UMR1313 Génétique Animale et Biologie Intégrative, F-75231, Paris 05, France. .,INRA, UMR1313 Génétique Animale et Biologie Intégrative, F-78352, Jouy-en-Josas, France.
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Y. BSZ, F. M, E. Z, G. MH, F. CC, M. C. Genetic structure and variability within and among populations of the fat-tailed Barbarine sheep breed using microsatellites markers. ACTA ACUST UNITED AC 2014. [DOI: 10.5897/ajb2013.13363] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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21
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Zhang L, Mousel MR, Wu X, Michal JJ, Zhou X, Ding B, Dodson MV, El-Halawany NK, Lewis GS, Jiang Z. Genome-wide genetic diversity and differentially selected regions among Suffolk, Rambouillet, Columbia, Polypay, and Targhee sheep. PLoS One 2013; 8:e65942. [PMID: 23762451 PMCID: PMC3677876 DOI: 10.1371/journal.pone.0065942] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Accepted: 04/30/2013] [Indexed: 11/18/2022] Open
Abstract
Sheep are among the major economically important livestock species worldwide because the animals produce milk, wool, skin, and meat. In the present study, the Illumina OvineSNP50 BeadChip was used to investigate genetic diversity and genome selection among Suffolk, Rambouillet, Columbia, Polypay, and Targhee sheep breeds from the United States. After quality-control filtering of SNPs (single nucleotide polymorphisms), we used 48,026 SNPs, including 46,850 SNPs on autosomes that were in Hardy-Weinberg equilibrium and 1,176 SNPs on chromosome × for analysis. Phylogenetic analysis based on all 46,850 SNPs clearly separated Suffolk from Rambouillet, Columbia, Polypay, and Targhee, which was not surprising as Rambouillet contributed to the synthesis of the later three breeds. Based on pair-wise estimates of FST, significant genetic differentiation appeared between Suffolk and Rambouillet (FST = 0.1621), while Rambouillet and Targhee had the closest relationship (FST = 0.0681). A scan of the genome revealed 45 and 41 differentially selected regions (DSRs) between Suffolk and Rambouillet and among Rambouillet-related breed populations, respectively. Our data indicated that regions 13 and 24 between Suffolk and Rambouillet might be good candidates for evaluating breed differences. Furthermore, ovine genome v3.1 assembly was used as reference to link functionally known homologous genes to economically important traits covered by these differentially selected regions. In brief, our present study provides a comprehensive genome-wide view on within- and between-breed genetic differentiation, biodiversity, and evolution among Suffolk, Rambouillet, Columbia, Polypay, and Targhee sheep breeds. These results may provide new guidance for the synthesis of new breeds with different breeding objectives.
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Affiliation(s)
- Lifan Zhang
- Department of Animal Sciences, Washington State University, Pullman, Washington, United States of America
| | - Michelle R. Mousel
- USDA/ARS US Sheep Experiment Station, Dubois, Idaho, United States of America
| | - Xiaolin Wu
- Department of Dairy Science, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Jennifer J. Michal
- Department of Animal Sciences, Washington State University, Pullman, Washington, United States of America
| | - Xiang Zhou
- Department of Animal Sciences, Washington State University, Pullman, Washington, United States of America
| | - Bo Ding
- Department of Animal Sciences, Washington State University, Pullman, Washington, United States of America
| | - Michael V. Dodson
- Department of Animal Sciences, Washington State University, Pullman, Washington, United States of America
| | - Nermin K. El-Halawany
- Cell Biology Department, Division of Genetic Engineering and Biotechnology, National Research Center, Dokki, Gueza, Egypt
| | - Gregory S. Lewis
- USDA/ARS US Sheep Experiment Station, Dubois, Idaho, United States of America
| | - Zhihua Jiang
- Department of Animal Sciences, Washington State University, Pullman, Washington, United States of America
- * E-mail:
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Affiliation(s)
- Phil Hedrick
- School of Life Sciences, Arizona State University, Tempe, AZ 85287
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Paiva SR, Mariante ADS, Blackburn HD. Combining US and Brazilian microsatellite data for a meta-analysis of sheep (Ovis aries) breed diversity: facilitating the FAO Global Plan of Action for Conserving Animal Genetic Resources. ACTA ACUST UNITED AC 2012; 102:697-704. [PMID: 22013019 DOI: 10.1093/jhered/esr101] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Microsatellites are commonly used to understand genetic diversity among livestock populations. Nevertheless, most studies have involved the processing of samples in one laboratory or with common standards across laboratories. Our objective was to identify an approach to facilitate the merger of microsatellite data for cross-country comparison of genetic resources when samples were not evaluated in a single laboratory. Eleven microsatellites were included in the analysis of 13 US and 9 Brazilian sheep breeds (N = 706). A Bayesian approach was selected and evaluated with and without a shared set of samples analyzed by each country. All markers had a posterior probability of greater than 0.5, which was higher than predicted as reasonable by the software used. Sensitivity analysis indicated no difference between results with or without shared samples. Cluster analysis showed breeds to be partitioned by functional groups of hair, meat, or wool types (K = 7 and 12 of STRUCTURE). Cross-country comparison of hair breeds indicated substantial genetic distances and within breed variability. The selected approach can facilitate the merger and analysis of microsatellite data for cross-country comparison and extend the utility of previously collected molecular markers. In addition, the result of this type of analysis can be used in new and existing conservation programs.
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Affiliation(s)
- Samuel Rezende Paiva
- EMBRAPA Recursos Genéticos e Biotecnologia, Laboratório de Genética Animal, Parque Estação Biológica, Brasília, DF 70770-917, Brazil.
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Genetic diversity of Ovis aries populations near domestication centers and in the New World. Genetica 2011; 139:1169-78. [DOI: 10.1007/s10709-011-9619-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Accepted: 11/12/2011] [Indexed: 11/25/2022]
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