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1.
We aimed to determine whether casein variants that are currently segregating in ovine populations existed before the domestication of sheep or, to the contrary, if their emergence is much more recent. To this end, we have retrieved whole-genome sequences from Iranian and domestic sheep from Africa, Europe, South and East Asia and West Asia. Population structure analysis based on 55,352,935 SNPs revealed a clear separation between Iranian mouflons and domestic sheep. Moreover, we also observed a strong genetic differentiation between Iranian mouflons sampled in geographic areas close to Tehran and Tabriz. Based on sequence data, hundreds of SNPs mapping to the casein αS1 (CSN1S1, 248 SNPs), casein αS2 (CSN1S2, 268 SNPs), casein ß (CSN2, 146 SNPs) and casein κ (CSN3, 112 SNPs) genes were identified. Approximately 25–63.02% of the casein variation was shared between Iranian mouflons and domestic sheep, and the four domestic sheep populations also shared 44.2–57.4% of the casein polymorphic sites. These findings suggest that an important fraction of the casein variation present in domestic sheep was already segregating in the mouflon prior to its domestication. Genomic studies performed in horses and dogs are consistent with this view, suggesting that much of the diversity that we currently detect in domestic animals comes from standing variation already segregating in their wild ancestors.  相似文献   

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Little is known of Toxoplasma gondii isolates circulating in wildlife. The mouflon (Ovis ammon) is very popular game animal, hunted for its trophy horns. Here, we report the isolation and genetic characterization of T. gondii from two mouflons from Hawaii, USA. Both sheep had antibodies titers of 1:800 or higher. Viable T. gondii were isolated and nested PCR‐RFLP genotyping revealed two genotypes, a clonal Type III (designated TgMouflonUS1), and a new genotype (designated TgMouflonUS2, and ToxoDB PCR‐RFLP genotypes #249). This is the first report of T. gondii infection, isolation and genetic characterization in mouflons from the USA.  相似文献   

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We show that Alpine ibex (Capra ibex) and Corsican mouflon (Ovis musimon) faeces yield useful DNA for microsatellite analysis, however, we detected higher genotyping error rates for spring faeces than for winter faeces. We quantified the genotyping error rate by repeatedly genotyping four microsatellites. Respectively, 99 and 95% of mouflon and ibex genotyping repetitions provided a correct genotype using winter samples, whereas spring samples provided only 52 and 59% correct genotypes. Thus, before starting a noninvasive study, we recommend that researchers conduct a pilot study to quantify genotyping error rates for each season, population and species to be studied.  相似文献   

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Benzidine staining of starch gels after electrophoresis of sera to which haematin was added revealed polymorphism of haemopexin in sheep, mouflon and goat. In sheep three phenotypes were observed, Hpx A, Hpx AB and Hpx B. Pedigree data support the hypothesis of codominant inheritance from a single locus by two alleles, HpxA and HpxB. Neuraminidase treatment of haemopexin preparations showed that Hpx B covered two variants, B1 and B2, thus indicating genetic control by three alleles (HpxA, HpxB1 and HpxB2). In sheep populations the frequency of HpxB is low. In mouflon, in addition to the two variants that are like those of sheep, absence of haemopexin was observed in some animals, by using starch gel electrophoresis as well as immunoelectrophoresis. In goat, three phenotypes were detected, Hpx A, Hpx AB and Hpx B, differing in migration from those of sheep. Haemopexins of the studied species are heterogeneous. Sialic acid is responsible for electrophoretic heterogeneity of sheep haemopexin. Chemical. composition (amino acid and carbohydrate), molecular weight (56 060) and N-terminal sequence (Leu-Pro-Pro-) of sheep haemopexin were also determined.  相似文献   

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The Haute Island mouflon (Ovis aries) population is isolated on one small (6.5 km2) island of the remote Kerguelen archipelago. Given a promiscuous mating system, a cyclic demography and a strong female-biased sex ratio after population crashes, we expected a low effective population size (Ne). We estimated Ne using demographic and temporal genetic approaches based on genetic information at 25 microsatellite loci from 62 and 58 mouflons sampled in 1988 and 2003, respectively. Genetic Ne estimates were higher than expected, varying between 104 and 250 depending on the methods used. Both demographic and genetic approaches show the Haute Island Ne is buffered against population crashes. The unexpectedly high Ne likely results from the cyclic winter crashes that allow young males to reproduce, limiting the variance of male reproductive success. Based on individual-based simulations, we suggest that despite a strongly female-biased sex ratio, the effects of the mating system on the effective population size more closely resemble random mating or weak polygyny.  相似文献   

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The heterogeneity of climate and different agro-ecological conditions in Iran have resulted in development of 27 indigenous sheep breeds. Wild Asiatic mouflon (Ovis orientalis) is believed to be the ancestor of Iranian sheep. Evaluation of genetic diversity and population structure within and among domestic breeds has important implications for animal breeding programs and genetic resources management. Based on 50K SNP genotype data, we studied the genetic diversity of five indigenous Iranian sheep breeds: Afshari (n = 37), Moghani (n = 34), Qezel (n = 35), Zel (n = 46) and Lori-Bakhtiari (n = 46), and Asiatic mouflon (n = 8) sampled from Iran. Furthermore, genetic diversity and the breed admixture of Iranian sheep were assessed on a larger geographic scale using a reference panel comprising: three indigenous Afghan breeds – Arabi (n = 15), Balouchi (n = 15) and Gadik (n = 15); three indigenous breeds from Turkey and Cyprus – Cyprus Fat Tail (n = 30), Karakas (n = 18) and Norduz (n = 20); and three commercial European breeds – Suffolk (n = 19), Comisana (n = 24) and Engadine Red Sheep (n = 24). The results revealed that the investigated breeds are divided into five genetically distinct clusters according to their geographic origin. Afshari was closest to the local mouflon population and showed signs of mouflon admixture. Qezel was identified as a hybrid sheep breed. Much evidence supported the Afghan breeds being identical. Inbreeding values, which were estimated based on ROHs, were highest for Suffolk (FROH = 0.0544) and lowest for Balouchi (FROH = 0.0078). In conclusion, analysis of selected breeds from neighboring countries along with Asiatic mouflon gave a deeper insight into the evolutionary history and origin of Iranian sheep with important implications for future breed management.  相似文献   

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Haemoglobin (Hb) phenotypes have been studied in 100 wild European mouflons living on the island of Sardinia by means of isoelectric focusing (pH 6.7-7.7 range) of the native tetramers, acid-urea-Triton gel-electrophoresis, and reversed-phase HPLC of globin chains. The result indicates the presence of two beta-globin alleles one of which, corresponding to the beta B, being the most common (f = 0.94). None were carriers of the earlier described Hb A. The new Hb was provisionally named Hb M. Severely anaemic mouflons were able to synthesize Hb C at expense of the Hb B alone, thus suggesting structural and physiological homologies between mouflon beta B and sheep beta A globin genes, and between the newly observed beta M allele and the beta B of the domestic Sardinian sheep.  相似文献   

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One-dimensional polyacrylamide gel electrophoresis (1D PAGE) followed by immunoblotting revealed genetic polymorphism of GC protein in sheep (variants F, S, V) and mouflon (variants F and S, apparently identical to F and S of sheep). The frequency of Gcs allele ranged from 0.84 to 1.0 in the 12 breeds of sheep studied. GcV allele was observed only in Tsigai breed with a frequency of 0.017.  相似文献   

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Biochemical variation at 14 blood loci was reviewed, and specific features compared experimentally in sheep Ovis aries, mouflon Ovis musimon, goat Capra hircus, aoudad Ammotragus lervia and in 2 stillborn aoudad × goat hybrids. Variation at 3 loci was also studied in dall sheep Ovis dalli, bighorn sheep Ovis canadensis and rocky mountain goat Oreamnos americanus. Haemoglobin C production in an anaemic Hb AB mouflon and in mouflon × sheep hybrids was examined. Mouflon differ from domestic sheep in that synthesis of both Hb βAHb βBchains is switched off during Hb C production. The mouflon × sheep hybrids switched off one or both chains depending on whether they had inherited sheep or mouflon Hb β chain genes. In general aoudad showed a closer affinity to goats than to sheep.  相似文献   

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Although the potential use of reproductive biotechnology for safeguarding of endangered wildlife species is undoubted, initial evaluation of the genetic and reproductive relationship between the endangered mammals and those closely related species is indispensable. Isfahan mouflon Ovis orientalis isphahanica is now considered as a threatened species by International Union for the Conservation of Nature. Therefore, little is known about the biology of this species. This study was carried out to investigate the possible reproductive potential of domestic sheep for ex situ conservation of the Isfahan mouflon. Somatic cell cultures were taken from ear biopsies of the wild and domestic sheep and were used for karyotype analysis. Semen samples were collected by electroejaculator from the wild and domestic rams. The spermatological characteristics of the collected semen samples were determined and used for both cryopreservation and cross-insemination of the synchronized wild and domestic female sheep. To establish a cryobank for the threatened species biomaterials, freezed samples of the somatic cells and semen were transferred to a cryotank. The result suggested that Isfahan mouflon has conserved its chromosomal integrity as previously observed and contains the same chromosomal number as the domestic sheep (2n = 54). The semen samples of both species revealed similar cryoviability (>35% gross motility postthawing). Cross-insemination of both species resulted in successful pregnancy. It was suggested that domestic sheep possesses the required biological characteristics to be considered for safeguarding of the Isfahan mouflon.  相似文献   

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The history and species status of free-ranging goats inhabiting the Eastern Mediterranean islands is discussed with reference to morphometric, archaeological and genetic findings. A case study on the free-ranging goats on Crete (Capra aegagrus cretica) is presented. The phenotype of the Cretan goat resembles that of the wild bezoar goat (C. aegagrus). However, the mitochondrial DNA of cytochrome b and d-loop sequences shows affinity with domestic goats. It has been suggested that the Cretan goat represents a feral animal that was introduced onto the island during the 6th millennium b.c. as a primitive domestic, and has retained the wild morphotype but has undergone significant genetic change. An alternative explanation, and the one that is proposed here, is that the goat was introduced onto the island in wild form and released as a food source. Subsequent introgressions with domestic animals, especially ewes, have influenced its genotype. These conclusions are applicable to other free-living goats and sheep which inhabit islands in the Eastern Mediterranean.  相似文献   

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We assessed the effects of prescribed burning and cutting on mouflon (Ovis gmelini musimon × Ovis sp.) spring habitat using an experimental design (17.28 ha) of 2 burned, 2 cut, and 2 untreated plots within a homogeneous stand dominated by heather (Erica cinerea and Calluna vulgaris). Overall, we found a shift in treated plots from ligneous species to herbaceous species with high digestive and energetic values for mouflon. We also found a consistently higher number of mouflon feeding on these treated habitats compared to untreated plots. Such effects were still apparent 4 years after habitat modifications. Our approaches could be used by managers to improve and maintain the range of mouflon populations experiencing habitat loss (e.g., woody plant encroachment) and for which the condition of an animal has often a high economical value through trophy hunting. © 2011 The Wildlife Society.  相似文献   

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