• Asian-Australasian Journal of Animal Sciences
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• v.20 no.3
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• pp.313-315
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• 2007

Seventeen haplotypes were detected from the complete mitochondrial DNA control region sequences analyzed from eighty individuals of two Tibetan domestic sheep breeds. The nucleotide composition of all the sequences was 33.0% A, 29.7%T, 22.9%C and 14.4%G; G+C was 37.3%. The length of the sequences ranged from 1,107 bp to 1,259 bp. The difference between them was primarily due to 3-5 copy numbers of a 75 bp tandem repeat sequence. The NJ phylogenetic tree (the number of replications of bootstrap test is 1,000) presented three major domestic sheep lineages, which suggested that modern Tibetan sheep breeds are derived from three maternal sources.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.4
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• pp.574-579
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• 2014

A lysozyme gene from breast of Tibetan sheep was successfully expressed by secretion using a-factor signal sequence in the methylotrophic yeast, Pichia pastoris GS115. An expression yield and specific activity greater than 500 mg/L and 4,000 U/mg was obtained. Results at optimal pH and temperature showed recombinant lysozyme has higher lytic activity at pH 6.5 and $45^{\circ}C$. This study demonstrates the successful expression of recombinant lysozyme using the eukaryotic host organism P. pastoris paving the way for protein engineering. Additionally, this study shows the feasibility of subsequent industrial manufacture of the enzyme with this expression system together with a high purity scheme for easy high-yield purification.

• Parasites, Hosts and Diseases
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• v.56 no.6
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• pp.603-607
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• 2018

This study was carried out to determine the pathogen-causing diarrhoea in sheep Ovis aries in the Qinghai Tibetan Plateau Area, China. A trophozoite was identified as species of ciliate alveolates infecting the sheep based on morphological characteristics examined by microscope. It was mostly spherical, colourless and transparent, with many vesicles. Macronucleus and contractile vacuoles could not be distinguished. Size of the trophozoite was $80-180{\times}70-150{\mu}m$ and its surface was covered with cilia. Molecular analysis based on sequences of 18S rRNA and ITS genes confirmed the ciliate species as Balantidium coli. According to the literature, there have been many epidemiological investigations of B. coli infection in pigs, monkeys and humans. To our knowledge, this was the first report of B. coli infections in sheep in the Qinghai Tibetan Plateau Area of China, or eleswhere around the world. Importantly, the sheep case was rare but raised our concern that B. coli may spread across species and expand its host range.

• Animal Bioscience
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• v.36 no.7
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• pp.991-1002
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• 2023

Objective: This study aimed to elucidate the underlying gene regions responsible for productive, phenotypic or adaptive traits in different ecological types of Tibetan sheep and the discovery of important genes encoding valuable traits. Methods: We used whole-genome resequencing to explore the genetic relationships, phylogenetic tree, and population genetic structure analysis. In addition, we identified 28 representative Tibetan sheep single-nucleotide polymorphisms (SNPs) and genomic selective sweep regions with different traits in Tibetan sheep by fixation index (Fst) and the nucleotide diversity (θπ) ratio. Results: The genetic relationships analysis showed that each breed partitioned into its own clades and had close genetic relationships. We also identified many potential breed-specific selective sweep regions, including genes associated with hypoxic adaptability (MTOR, TRHDE, PDK1, PTPN9, TMTC2, SOX9, EPAS1, PDGFD, SOCS3, TGFBR3), coat color (MITF, MC1R, ERCC2, TCF25, ITCH, TYR, RALY, KIT), wool traits (COL4A2, ERC2, NOTCH2, ROCK1, FGF5, SOX9), and horn phenotypes (RXFP2). In particular, a horn-related gene, RXFP2, showed the four most significantly associated SNP loci (g. 29481646 A>G, g. 29469024 T>C, g. 29462010 C>T, g. 29461968 C>T) and haplotypes. Conclusion: This finding demonstrates the potential for genetic markers in future molecular breeding programs to improve selection for horn phenotypes. The results will facilitate the understanding of the genetic basis of production and adaptive unique traits in Chinese indigenous Tibetan sheep taxa and offer a reference for the molecular breeding of Tibetan sheep.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.9
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• pp.1378-1386
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• 2020

Objective: Chinese indigenous sheep breeds can be classified into the following three categories by their tail morphology: fat-tailed, fat-rumped and thin-tailed sheep. The typical sheep breeds corresponding to fat-tailed, fat-rumped, and thin-tailed sheep are large-tailed Han, Altay, and Tibetan sheep, respectively. Detection of copy number variation (CNV) and selection signatures provides information on the genetic mechanisms underlying the phenotypic differences of the different sheep types. Methods: In this study, PennCNV software and F-statistics (F_ST) were implemented to detect CNV and selection signatures, respectively, on the X chromosome in three Chinese indigenous sheep breeds using ovine high-density 600K single nucleotide polymorphism arrays. Results: In large-tailed Han, Altay, and Tibetan sheep, respectively, a total of six, four and 22 CNV regions (CNVRs) with lengths of 1.23, 0.93, and 7.02 Mb were identified on the X chromosome. In addition, 49, 34, and 55 candidate selection regions with respective lengths of 27.49, 16.47, and 25.42 Mb were identified in large-tailed Han, Altay, and Tibetan sheep, respectively. The bioinformatics analysis results indicated several genes in these regions were associated with fat, including dehydrogenase/reductase X-linked, calcium voltage-gated channel subunit alpha1 F, and patatin like phospholipase domain containing 4. In addition, three other genes were identified from this analysis: the family with sequence similarity 58 member A gene was associated with energy metabolism, the serine/arginine-rich protein specific kinase 3 gene was associated with skeletal muscle development, and the interleukin 2 receptor subunit gamma gene was associated with the immune system. Conclusion: The results of this study indicated CNVRs and selection regions on the X chromosome of Chinese indigenous sheep contained several genes associated with various heritable traits.

• Animal Bioscience
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• v.34 no.12
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• pp.1921-1929
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• 2021

Objective: The intestinal microbiota enhances nutrient absorption in the host and thus promotes heath. Qinghai semi-fine wool sheep is an important livestock raised in the Qinghai-Tibetan Plateau; however, little is known about the bacterial microbiota of its intestinal tract. The aim of this study was to detect the microbial characterization in the intestinal tract of the Qinghai semi-fine wool sheep. Methods: The bacterial profiles of the six different intestinal segments (duodenum, jejunum, ileum, cecum, colon and rectum) of Qinghai semi-fine wool sheep were studied using 16S rRNA V3-V4 hypervariable amplicon sequencing. Results: A total of 2,623,323 effective sequences were obtained, and 441 OTUs shared all six intestinal segments. The bacterial diversity was significantly different among the different intestinal segments, and the large intestine exhibited higher bacterial diversity than the small intestine. Firmicutes, Bacteroidetes, and Patescibacteria were the dominant phyla in these bacterial communities. Additionally, at the genus level, Prevotella_1, Candidatus_Saccharimonas, and Ruminococcaceae_UCG-005 were the most predominant genus in duodenal segment, jejunal and ileal segments, and cecal, colonic, and rectal segments, respectively. We predicted that the microbial functions and the relative abundance of the genes involved in carbohydrate metabolism were overrepresented in the intestinal segments of Qinghai semi-fine wool sheep. Conclusion: The bacterial communities and functions differed among different intestinal segments. Our study is the first to provide insights into the composition and biological functions of the intestinal microbiota of Qinghai semi-fine wool sheep. Our results also provide useful information for the nutritional regulation and production development in Qinghai semi-fine wool sheep.

• BMB Reports
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• v.40 no.3
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• pp.426-431
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• 2007

To investigate the possible mechanisms of high-altitude native animals in adapting to high altitude, we cloned hemoglobin alpha-chain (alpha-chain Hb) gene from Pantholops hodgsonii, an animal species that indigenously lives at elevations of 3700-5500 m on the Qinghai-Tibetan plateau. Using reverse transcription polymerase chain reaction (RT-PCR) technique, the alpha-chain Hb gene was amplified from total RNA in the liver of the Pantholops hodgsonii. TA cloning technique was used and the PCR product was cloned into pGEM-T vector. The DNA sequence of the gene was highly homologous with sheep (99.1%), goat (98.6%), cattle (95.6%) and human (86.5%). The alpha-chain Hb gene encoded a 142-amino acid protein that could be identified with the homology of alpha-chain Hb protein in sheep (98%), goat (96%), cattle (91%) and human (87%). However, 18 alternations were detected when compared with the alpha-chain Hb gene in human, and 2 in sheep. Moreover, the alterations of a117 GluAsp and $\alpha$132 AsnSer in important regions were noted in human and sheep, respectively. Phylogenetic analysis suggested that the structure of alpha-chain Hb was highly similar to that in sheep. This study provided essential information for elucidating the possible roles of hemoglobin in adapting to extremely high altitude in Pantholops hodgsonii.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.10
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• pp.1630-1639
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• 2019

Objective: Sixty Pengbo semi-wool sheep ewes (approximately 1.5-years-old; $31.33{\pm}0.43kg$) were randomly assigned to two groups, either grazing (G) or dry lot feeding (D), to examine the effects of traditional daily grazing and dry lot feeding on performance and blood metabolites during the cold season in Tibetan Plateau. Methods: The ewes in the G group were grazed continuously each day and housed in one shed each evening, while the ewes in the D group were housed in another shed all day. All animals were fed 400 g/d of commercial concentrate, and grass hay was available freely throughout the experimental period. Results: Compared with the G group, the ewes in the D group had higher (p<0.05) live weight and weight gain. The D group ewes had greater (p<0.05) numbers of white blood cells and platelets, while they had lower (p<0.05) platelet-large cell ratios, cholesterol, high-density lipoprotein cholesterol and glutathione peroxidase, as compared with the G group ewes. Additionally, three serum metabolites, abscisic acid, xanthoxin and 3,4-dihydroxy-5-polypren, were upregulated (p<0.05) in the G group in comparison with the D group. Conclusion: In conclusion, a dry lot feeding regime during the winter and spring period will increase the productivity of sheep and improve blood physiological and biochemical profiles.

• Parasites, Hosts and Diseases
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• v.57 no.4
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• pp.423-427
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• 2019

Coenurosis is an important zoonotic helminthic disease caused by the larval stage of the tapeworm Taenia multiceps. This parasite typically infects the brain of the intermediate hosts, including sheep, goat, cattle and even humans. We report a case of T. multiceps infection in a yak confirmed by clinical symptoms, morphological characteristics, and molecular and phylogenetic analyses. The coenurus was thin-walled, whitish, and spherical in shape with a diameter of 10 cm. The parasite species was identified as T. multiceps by PCR amplification and sequencing of the 18S rRNA, cox1 and nad1 genes. Three gene sequences all showed high homology (all above 97%) with the reference sequences from different hosts. Moreover, phylogenetic reconstructions with the 3 published Taenia gene sequences confirmed that the Qinghai yak isolate was closely related to T. multiceps. Although there are advanced diagnosis and treatment methods for coenurosis, early infection is difficult to diagnose. Importantly, the findings of yak infection case should not be ignored due to its zoonotic potential.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.9
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• pp.1183-1187
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• 2004

The natural resistance-associated macrophage protein 1 (NRAMP1) gene was identified as a candidate gene controlling the resistance and susceptibility to a number of intracellular parasites in pigs. The genetic variations in a 1.6 kb region spanning exon 1 and exon 3 of the porcine NRAMP1 gene were investigated by PCR-HinfI-RFLP in samples of 1347 individuals from 21 Chinese indigenous pig populations and 3 western pig breeds. Three alleles (A, B, C) and four genotypes (AA, BB, AB, BC) were detected. Significant differences in genotype and allele frequencies were observed between Chinese indigenous pig populations and exotic pig breeds, while in general the differences in genotype and allele frequencies among Chinese indigenous pig populations were not significant. The allele C was detected only in Duroc, Leping Spotted and Dongxiang Spotted pig, and the two Chinese pig populations showed similar genotype and allele frequencies. Four Chinese Tibetan pig populations displayed genetic differentiation at the NRAMP1 gene locus. In addition, intron 5 of the NRAMP1 gene was isolated and characterized by directly sequencing the PCR products encompassing intron 5. The alignment of intron 5 of the porcine, human, equine and ovine NRAMP1 gene showed a similarity of 45.38% between pig and human, 52.55% between pig and horse, 63.47% between pig and sheep, respectively.