• Asian-Australasian Journal of Animal Sciences
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• 제33권12호
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• pp.1905-1911
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• 2020

Objective: Tibetan pigs, an excellent species unique to China, face serious threats, which in turn affects the development and utilization of the outstanding advantages of plateau hypoxia adaptability and reduces their genetic diversity. Therefore, a discussion of measures to conserve this genetic resource is necessary. The method, based on genetic diversity, genetic divergence and total genetic contribution rate of population, reflects the priority conservation order and varies depending on the three different purposes of conservation. Methods: We analyzed mitochondrial DNA control region (D-loop) variation in 1,201 individuals from nine Tibetan pig populations across five provinces and downloaded 564 mtDNA D-loop sequences from three indigenous pig breeds in Qinghai, Sichuan, and Yunnan Provinces distributed near the Tibetan pigs. Results: We analyzed three different aspects: Changdu Tibetan pigs have the highest genetic diversity, and from the perspective of genetic diversity, the priority conservation is Changdu Tibetan pigs. Hezuo Tibetan pigs have the highest genetic contribution, so the priority conservation is Hezuo Tibetan pigs in the genetic contribution aspect. Rkaze Tibetan pigs were severely affected by indigenous pig breeds, so if considering from the perspective of introgression, the priority conservation is Rkaze Tibetan pigs. Conclusion: This study evaluated genetic diversity and comprehensively assessed conservation priority from three different aspects in nine Tibetan pig populations.

• Asian-Australasian Journal of Animal Sciences
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• 제27권6호
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• pp.898-906
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• 2014

The objective of this study was to investigate differences in the faecal microbial composition among Lantang, Bama, Erhualian, Meishan, Xiaomeishan, Duroc, Landrace, and Yorkshire sows and to explore the possible link of the pig breed with the gut microbial community. Among the sows, the Meishan, Landrace, Duroc, and Yorkshire sows were from the same breeding farm with the same feed. Fresh faeces were collected from three sows of each purebred breed for microbiota analysis and volatile fatty acid (VFA) determination. Denaturing gradient gel electrophoresis (DGGE) analysis revealed that samples from Bama, Erhualian, and Xiaomeishan sows, which from different farms, were generally grouped in one cluster, with similarity higher than 67.2%, and those from Duroc, Landrace, and Yorkshire sows were grouped in another cluster. Principal component analysis of the DGGE profile showed that samples from the foreign breeds and the samples from the Chinese indigenous breeds were scattered in two different groups, irrespective of the farm origin. Faecal VFA concentrations were significantly affected by the pig breed. The proportion of acetate was higher in the Bama sows than in the other breeds. The real-time PCR analysis showed that 16S rRNA gene copies of total bacteria, Firmicutes and Bacteroidetes were significantly higher in the Bama sows compared to Xiaomeishan and Duroc sows. Both Meishan and Erhualian sows had higher numbers of total bacteria, Firmicutes, Bacteroidetes and sulphate-reducing bacteria as compared to Duroc sows. The results suggest that the pig breed affects the composition of gut microbiota. The microbial composition is different with different breeds, especially between overseas breeds (lean type) and Chinese breeds (relatively obese type).

• 생명과학회지
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• 제21권3호
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• pp.341-348
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• 2011

제주재래돼지의 모계 혈통에 대한 보다 명확한 이해를 얻기 위해, 본 연구에서는 제주재래돼지의 미토콘드리아 DNA (mtDNA) CYTB 유전자를 분석하고 이를 타 품종들에서 얻은 결과들과 비교하였다. 제주재래돼지를 포함한 돼지 6 품종에서 PCR-RFLP 분석을 수행하였고, RFLP 양상은 돼지 품종들을 뚜렷하게 구분되는 두 가지 반수체형(mtCYTB1 and mtCYTB2)으로 분리시켰다. 제주재래돼지 CYTB 서열들은 계통수 상에서 유럽과 아시아품종 cluster에서 모두 발견되었다. 제주재래돼지 CYTB들 중에서 J2 group은 중국재래돼지품종들과 근연이면서 아시아 고유 돼지 계통들과 함께 출현하였으며, 다른 한 group인 J1에 해당하는 서열들은 유럽돼지 계통들과 함께 위치하였고, 아시아 품종들보다는 스페인의 Iberian 재래돼지들과 근연인 것으로 확인되었다. 이 결과들은 현재 제주도에서 사육되고 있는 제주재래돼지 품종의 모계 기원은 크게 아시아계 돼지와 유럽계 돼지인 것으로 추정됨을 보여준다. 따라서 본 연구결과들은 제주재래돼지 집단은 과거에 가축화된 아시아 고유 돼지품종들과 공통 선조를 공유하고, 또한 20세기에 유입된 유럽계 돼지 품종들도 현재의 집단 형성에 기여한 것임을 시사하고 있다.

• Asian-Australasian Journal of Animal Sciences
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• 제15권2호
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• pp.179-183
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• 2002

The fragment in intron I of FSH-${\beta}$ gene was amplified by PCR. According to the polymorphism, we analyzed the distribution of FSH-${\beta}$ retroposon in different pig breeds; its inheritance pattern in Large White${\times}$Meishan reference family; and the association of FSH-${\beta}$ retroposon with litter size, female reproductive organs measurement, ultrasonic backfat and other traits. The results showed that almost each Chinese indigenous pig had the retroposon, while foreign pig breeds rarely had; the frequencies of porcine FSH-${\beta}$ retroposon were strongly associated with breeds (p<0.01); the pattern of inheritance was consistent with Mendelian fashion; total number born (TNB) and number born alive (NBA) were increased per FSH-${\beta}$ retroposon (p<0.01) with additive effects of 1.2-1.8 and 1.4-1.8 pigs/litter, respectively; between the FSH-${\beta}$ retroposon carriers and non-carriers, there was an insignificant difference in the measurement of female reproductive organs, body weight at birth, backfat thickness, loin meat height, lean meat percentage, teat number, days to 100 kg, and average daily gain.

• Asian-Australasian Journal of Animal Sciences
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• 제17권5호
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• pp.598-602
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• 2004

The Tongcheng pig breed is a famous Chinese indigenous breed. The Ministry of Agriculture of China has filed it as 1 of 19 national key conservation breeds selected from more than 100 Chinese indigenous pig breeds in 2000. In order to improve the reproductive performance, it has been intensively selected to increase the litter size for about 10 years. The population randomly sampled from conservation nucleus of eight families in the Tongcheng pigs was genotyped for identification of their estrogen receptor locus polymorphisms with the PCR-RFLPs method. Only AB heterozygotes and BB homozygotes were detected, and $X^2$ test demonstrated that the locus was in disequilibrium at a significant level (p<0.05). In the present paper, the litter sizes in different parities were regarded as different traits. Holistic status of other unspecific and unidentified genes was estimated by using the statistical methods. Coefficients of kurtosis and skewness showed that the litter size still presented segregating characteristic in the 2nd, 5th, 7th, 8th and 9th parities. Analysis of homogeneity of variance between families confirmed the results for the 5th, 7th and 8th parities. The heritability of litter size for the 1st to 10th parities was estimated with paternal half-sib model and individual estimated breeding values (EBVs) were evaluated by a single trait animal model as well. We found that the averages of EBVs for litter size in each parity did not differ significantly between genotypes, despite the significant difference for original phenotype records in the 3rd, 4th and 5th parities (p<0.05 or p<0.01). The results may be explained by the deduction that the polymorphisms of ESR locus are no longer the important genetic base of litter size variation when the frequency of allele B accumulated in the experience of selection procedure, and further conferring that there exist special genes associated with litter size in the recent Tongcheng pigs population can be made.

• Asian-Australasian Journal of Animal Sciences
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• 제19권7호
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• pp.931-937
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• 2006

The full-length cDNA of the porcine SMPX gene was obtained by the rapid amplification of cDNA ends (RACE). The nucleotide sequences and the predicted protein sequences share high sequence identity with both human and mouse. The promoter of SMPX was sequenced and then analyzed to find the promoter binding sites. The reverse transcriptase-polymerase chain reaction (RT-PCR) revealed that SMPX has a high level of expression in heart and skeletal muscle, a very low expression in lung and spleen and no expression in liver, kidney, fat and brain. Moreover, SMPX has a differential expression level in skeletal muscle, the expression in 65-day embryos being higher than other stages. The porcine SMPX was mapped to SSCXp24 by using a somatic cell hybrid panel (SCHP) and was found closely linked to SW1903 using the radiation hybrid panel IMpRH. An A/G single nucleotide polymorphism (PCR-RFLP) in the 3'-untranslated region (3'-UTR) was detected in eight breeds. The analysis of allele frequency distribution showed that introduced pig breeds (Duroc and Large White) have a higher frequency of allele A while in the Chinese indigenous pig breeds (Qingping pig, Lantang pig, YushanBlack pig, Large Black-White pig, Small Meishan) have a higher frequencies of allele G. The association analysis using an experimental population (188 pigs), which included two cross-bred groups and three pure-blood groups, suggested that the SNP genotype was associated with intramuscular fat content.

• Asian-Australasian Journal of Animal Sciences
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• 제33권5호
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• pp.712-721
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• 2020

Objective: The Wannan Black pig is a typical Chinese indigenous, disease-resistant pig breed with high fertility, and a crude-feed tolerance that has been bred by artificial selection in the south of Anhui province for a long time. However, genome variation, genetic relationships with other pig breeds, and domestication, remain poorly understood. Here, we focus on elucidating the genetic characteristics of the Wannan Black pig and identifying selection signatures during domestication and breeding. Methods: We identified the whole-genome variation in the Wannan Black pig and performed population admixture analyses to determine genetic relationships with other domesticated pig breeds and wild boars. Then, we identified the selection signatures between the Wannan Black pig and Asian wild boars in 100-kb windows sliding in 10 kb steps by using two approaches: the fixation index (F_ST) and π ratios. Results: Resequencing the Wannan Black pig genome yielded 501.52 G of raw data. After calling single-nucleotide variants (SNVs) and insertions/deletions (InDels), we identified 21,316,754 SNVs and 5,067,206 InDels (2,898,582 inserts and 2,168,624 deletions). Additionally, we found genes associated with growth, immunity, and digestive functions. Conclusion: Our findings help in explaining the unique genetic and phenotypic characteristics of Wannan Black pigs, which in turn can be informative for future breeding programs of Wannan Black pigs.

• Journal of Animal Science and Technology
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• 제46권6호
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• pp.903-908
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• 2004

다양한 포유동물의 미토콘드리아 유전자들에서 선택적 개시코돈(AIC)들이 보고되었다. 본 연구는 돼지 5 품종에서 mtDNA ND2 유전자의 AIC 양상을 분석하였다. 두 종류의 AIC 서열들이 발견되었고, 품종 집단간에서 각기 다른 출현빈도를 보였다. ND2의 methionine codon으로 Large White와 Landrace는 각각 전 개체에서 ATA와 ATT 서열로 확인되었다. 다른 3 품종(Berkshire, Duroc, Hampshire)의 경우는 두 서열이 모두 발생하였으며, 91.9, 21.3, 60.0%의 빈도로 ATA를 보였다. 기존의 연구들에 의하면 중국재래돼지들이 모두 개시코돈 ATA를 갖는다고 보고되어 있다. 미토콘드리아 ND2 단백질의 합성과정에서 AIC가 어떤 영향을 미치는지는 설명할 수 없으나, 본 연구에서 나타난 AIC 다형성과 품종특이적인 분포양상은 돼지의 육종에 있어 모계추적을 위한 분자적 표지인자로서 이용될 수 있을 것을 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권9호
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• pp.1237-1241
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• 2005

Mannose-P-dolichol utilization defect 1 (MPDU1) gene is required for utilization of the mannose donor MPD in synthesis of both lipid-linked oligosaccharides (LLOs) and glycosylphosphatidylinositols (GPI) which are important for functions such as protein folding and membrane anchoring. The full length cDNA of the porcine MPDU1 was determined by in silico cloning and rapid amplification of cDNA ends (RACE). The deduced amino acid showed 91% identity to the corresponding human sequence with five predicted transmembrane regions. RT-PCR was performed to detect its expression pattern in five tissues and results showed that it is expressed ubiquitously among the tissues checked. A single nucleotide substitution resulting in the amino acid change (137 Tyr-137 His) was detected within exon 5. Allele frequencies in six pig breeds showed distinctive differences between those Chinese indigenous pigs breeds and European pigs. Using the pig/rodent somatic cell hybrid panel (SCHP), we mapped the porcine MPDU1 gene to SSC12, which is consistent with the comparative mapping result as conservative syntenic groups presented between human chromosome 17 and pig chromosome 12.

• Asian-Australasian Journal of Animal Sciences
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• 제14권7호
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• pp.910-914
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• 2001

The teat number of a sow plays an important role for weaning pigs and has been utilized in selection of swine breeding stock. Various linear models have been employed for genetic analyses of teat number although the teat number can be considered as a count trait. Theoretically, Poisson error mixed models are more appropriate for count traits than Normal error mixed models. In this study, the two models were compared by analyzing data simulated with Poisson error. Considering the mean square errors and correlation coefficients between observed and fitted values, the Poisson generalized linear mixed model (PGLMM) fit the data better than the Normal error mixed model. Also these two models were applied to analyzing teat numbers in four breeds of swine (Landrace, Yorkshire, crossbred of Landrace and Yorkshire, crossbred of Landrace, Yorkshire, and Chinese indigenous Min pig) collected in China. However, when analyzed with the field data, the Normal error mixed model, on the contrary, fit better for all the breeds than the PGLMM. The results from both simulated and field data indicate that teat numbers of swine might not have variance equal to mean and thus not have a Poisson distribution.