• Asian-Australasian Journal of Animal Sciences
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• 제33권10호
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• pp.1566-1572
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• 2020

Objective: The extensive breeding of commercial chickens has led to a sharp decrease in the resources of many indigenous chickens, especially the indigenous chickens in the southeastern coastal region, which are on the verge of extinction, and the indigenous chickens in the northwestern region of China, which are also at risk. However, there are few reports on the evaluation of genetic diversity and conservation of genetic resources of indigenous chickens in remote areas in the Northwest of China. Methods: In the present study, the genetic diversity and phylogenetic relationship of six indigenous chickens from different regions were studied based on variation in mitochondrial DNA control region (D-loop), and the degree of introgression from commercial breeds into these chickens was determined by the amount of haplotype sharing between indigenous and commercial breeds. Results: Twenty-five polymorphic sites and 25 haplotypes were detected in 206 individuals. Principal component analysis showed that the Jingning chicken had the highest genetic diversity among the six indigenous chickens. According to the degree of introgression, the six indigenous breeds may be involved in haplotype sharing with commercial breeds, and the introgression from commercial chickens into the Haidong chicken is the most serious. Conclusion: The genetic uniqueness of indigenous chickens has been eroded, so it is necessary to consider the protection of their genetic resources. Phylogenetic analysis suggests that the six indigenous chickens have two major matrilineal origins: one from Yunnan or its surrounding areas in China and the other from the Indian subcontinent.

• Asian-Australasian Journal of Animal Sciences
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• 제30권7호
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• pp.930-937
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• 2017

Objective: The I pig is a long nurtured longstanding breed in Vietnam, and contains excellent indigenous genetic resources. However, after 1970s, I pig breeds have become a small population because of decreasing farming areas and increasing pressure from foreign breeds with a high growth rate. Thus, there is now the risk of the disappearance of the I pigs breed. The aim of this study was to focus on classifying and identifying the I pig genetic origin and supplying molecular makers for conservation activities. Methods: This study sequenced the complete mitochondrial genome and used the sequencing result to analyze the phylogenetic relationship of I pig with Asian and European domestic pigs and wild boars. The full sequence was annotated and predicted the secondary tRNA. Results: The total length of I pig mitochondrial genome (accession number KX094894) was 16,731 base pairs, comprised two rRNA (12S and 16S), 22 tRNA and 13 mRNA genes. The annotation structures were not different from other pig breeds. Some component indexes as AT content, GC, and AT skew were counted, in which AT content (60.09%) was smaller than other pigs. We built the phylogenetic trees from full sequence and D loop sequence using Bayesian method. The result showed that I pig, Banna mini, wild boar (WB) Vietnam and WB Hainan or WB Korea, WB Japan were a cluster. They were a group within the Asian clade distinct from Chinese pigs and other Asian breeds in both phylogenetic trees (0.0004 and 0.0057, respectively). Conclusion: These results were similar to previous phylogenic study in Vietnamese pig and showed the genetic distinctness of I pig with other Asian domestic pigs.

• 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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• 제21권12호
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• pp.1696-1702
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• 2008

In order to learn the origin of the Chinese Mongolian horse, we analyzed polymorphisms within the mtDNA D-loop variable region in 305 horses of 6 types of 3 different breeds, including one imported breed, one cultivated breed and 4 types of one local breed. We detected 13 different haplotypes, and subsequent sequence analysis showed that all 6 horse types were genetically diverse. By constructing a cladogram of mtDNA D-loop sequences from the 6 horse types along with homologous sequences from several other horse types obtained from GenBank, we showed that Chinese Mongolian horses have a close genetic relationship with other horse types from Mongolia. We also speculate that several Chinese Mongolian horses descended from Przewalskii horse. Additionally, the 13 haplotypes were dispersed throughout the cladogram, suggesting that Chinese Mongolian horses likely originated from multiple female ancestors. A phylogenetic map of the 6 horse types showed that the genetic relationship between the local Wuzhumuqin and Wushen types were the closest. The Xinihe and Baerhu were also closely related to each other, and slightly more distantly related to the cultivated Sanhe breed. All five of the local Chinese horse types had a much more distant relationship with the imported Thoroughbred breed.

• Asian-Australasian Journal of Animal Sciences
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• 제20권12호
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• pp.1805-1811
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• 2007

A simulation study was conducted to evaluate the effect of reciprocal cross on the detection and characterization of parent-of-origin (POE) QTL in $F_2$ QTL populations. Data were simulated under two different mating designs. In the one-way cross design, six $F_0$ grand sires of one breed and 30 $F_0$ grand dams of another breed generated 10 $F_1$ offspring per dam. Sixteen $F_1$ sires and 64 $F_1$ dams were randomly chosen to produce a total of 640 $F_2$ offspring. In the reciprocal design, three $F_0$ grand sires of A breed and 15 $F_0$ grand dams of B breed were mated to generate 10 $F_1$ offspring per dam. Eight $F_1$ sires and 32 $F_1$ dams were randomly chosen to produce 10 $F_2$ offspring per $F_1$ dam, totaling 320 $F_2$ offspring. Another mating set comprised three $F_0$ grand sires of B breed and 15 $F_0$ grand dams of A breed to produce the same number of $F_1$ and $F_2$ offspring. A chromosome of 100 cM was simulated with large, medium or small QTL with fixed or different allele frequencies in parental breeds. A series of tests between Mendelian and POE models were applied to characterize QTL as Mendelian, paternal, maternal or partial expression QTL. The overall detection powers were similar between the two mating designs. However, the proportions of paternally expressed QTL that were declared as paternal QTL type were greater in the reciprocal cross design than in the one-way cross, and vice versa for Mendelian QTL. When QTL alleles were segregating in parental breeds, a significant proportion of Mendelian QTL were spuriously declared POE QTL, suggesting that care must be taken to characterize imprinting QTL in a QTL mapping population with a small number of $F_1$ parents.

• Asian-Australasian Journal of Animal Sciences
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• 제33권6호
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• pp.902-912
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• 2020

Objective: Mongolia is one of a few countries that supports over 25 million goats, but genetic diversity, demographic history, and the origin of goat populations in Mongolia have not been well studied. This study was conducted to assess the genetic diversity, phylogenetic status and population structure of Mongolian native goats, as well as to discuss their origin together with other foreign breeds from different countries using hypervariable region 1 (HV1) in mtDNA. Methods: In this study, we examined the genetic diversity and phylogenetic status of Mongolian native goat populations using a 452 base-pair long fragment of HVI of mitochondrial DNA from 174 individuals representing 12 populations. In addition, 329 previously published reference sequences from different regions were included in our phylogenetic analyses. Results: Investigated native Mongolian goats displayed relatively high genetic diversities. After sequencing, we found a total of 109 polymorphic sites that defined 137 haplotypes among investigated populations. Of these, haplotype and nucleotide diversities of Mongolian goats were calculated as 0.997±0.001 and 0.0283±0.002, respectively. These haplotypes clearly clustered into four haplogroups (A, B, C, and D), with the predominance of haplogroup A (90.8%). Estimates of pairwise differences (Fst) and the analysis of molecular variance values among goat populations in Mongolia showed low genetic differentiation and weak geographical structure. In addition, Kazakh, Chinese (from Huanghuai and Leizhou), and Arabian (Turkish and Baladi breeds) goats had smaller genetic differentiation compared to Mongolian goats. Conclusion: In summary, we report novel information regarding genetic diversity, population structure, and origin of Mongolian goats. The findings obtained from this study reveal that abundant haplogroups (A to D) occur in goat populations in Mongolia, with high levels of haplotype and nucleotide diversity.

• International Journal of Industrial Entomology and Biomaterials
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• 제9권1호
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• pp.41-46
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• 2004

A breeding programme was initiated by utilizing a robust bivoltine breed CSR$_{18}$ and a polyvoltine breed Cambodge with the main objective of developing robust polyvoltine silkworm breeds/hybrids. At F$_1$ and F$_2$, parthenogenetic development was induced following warm water treatment of eggs at 46$^{\circ}C$ for 18 min followed by two backcrosses with Bl$_{67}$, an evolved polyvoltine breed. The newly developed breed was subjected for hybrid study using eight hybrid combinations in the laboratory at F$_{8}$ generation. F$_1$ hybrids between newly developed breed Bl$_{67}$ (Pg) and promising bivoltine breeds exhibited their superiority by expressing significant hybrid vigour for several economic characters like cocoon yield/10,000 larvae, cocoon weight, cocoon shell weight, cocoon shell ratio and denier. Study on cocoon shape variability revealed that cocoons of all the F$_1$ hybrids except BL$_{67}$ (Pg)${\times}$NB$_4$D$_2$ were found comparatively uniform in shape.pe.

• 현장농수산연구지
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• 제24권1호
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• pp.36-40
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• 2022

The purpose of this study was to evaluate hippological differences between Jeju ponies and Jeju Pony crossbreds population. This is the first repot of the differences use an anhidrosis in Korean native horses. The precise prevalence of anhidrosis is unknown; however, it has been estimated that 6-20% of horses may be affected. However, there is no report about the incidence of the disease in pony breeds. We performed diagnosis by clinical signs (sweating) to investigate the incidence of anhidrosis in Jeju Ponies(n=340) and Jeju Pony crossbreds (n=536) at Jeju Race Park from July to September in 2012 as a way of find of hippological difference. Results of this study showed that 74 (21.8%) of the 340 examined Jeju Ponies and 61 (11.4%) of the 536 examined Jeju Pony crossbreds had anhidrosis. So, the former had almost two times higher than the later. Among 74 Jeju Ponies those had the disease, 50 were male (23.1%) and 24 were female (19.4%). Among 61 Jeju Pony crossbreds those had the disease, 22 were male (9.5%) and 39 were female (12.8). In Jeju Ponies, anhidrosis were most common in above the age of 5, followed by 4, 2, 3-years-old. For Jeju Pony crossbreds, the disease were most common in 2-years-old, followed by above the age of 5, 4, 3-years-old. In two breeds, 3-year-old animals were most rare respectively. There was no predilection of age and sex which is correlated with another study. In conclusion, the incidence of anhidrosis in the ponies were considerably similar foreign countries. However, the authors thought that causes of the difference of the breeds were origin and genetic differences.

• Asian-Australasian Journal of Animal Sciences
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• 제28권8호
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• pp.1066-1074
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• 2015

In contrast to high genetic diversity of mitochondrial DNA (mtDNA), equine Y chromosome shows extremely low variability, implying limited patrilines in the domesticated horse. In this study, we applied direct sequencing and restriction fragment length polymorphism (RFLP) methods to investigate the polymorphisms of 33 Y chromosome specific loci in 304 Chinese indigenous horses from 13 breeds. Consequently, two Y-single nucleotide polymorphisms (SNPs) (Y-45701/997 and Y-50869) and one Y-indel (Y-45288) were identified. Of those, the Y-50869 (T>A) revealed the highest variation frequency (24.67%), whereas it was only 3.29% and 1.97% in Y-45288 (T/-) and Y-45701/997 (G>T) locus, respectively. These three mutations accounted for 27.96% of the total samples and identified five Y-SNP haplotypes, demonstrating genetic diversity of Y chromosome in Chinese horses. In addition, all the five YSNP haplotypes were shared by different breeds. Among 13 horse breeds analyzed, Balikun horse displayed the highest nucleotide diversity (${\pi}=5.6{\times}10^{-4}$) and haplotype diversity (h = 0.527), while Ningqiang horse showed the lowest nucleotide diversity (${\pi}=0.00000$) and haplotype diversity (h = 0.000). The results also revealed that Chinese horses had a different polymorphic pattern of Y chromosome from European and American horses. In conclusion, Chinese horses revealed genetic diversity of Y chromosome, however more efforts should be made to better understand the domestication and paternal origin of Chinese indigenous horses.

• 현장농수산연구지
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• 제25권4호
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• pp.39-43
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• 2024

Little research has been done on investigating the specific characteristics of Jeju Ponies (Korean native horse) and Jeju Pony crossbreds. The authors performed evaluation of skin thickness of the skin of these breeds (n=205) at Jeju Race Park as a way of find of hippological difference. Results of this study showed that the Jeju Pony's skin were thicker than the Jeju Pony crossbred. The male's skin were thicker than the female's skin in two breeds respectively. Especially, in the Jeju Pony show significant differences (P < 0.05). In Jeju Pony crossbreds, as the skin thickness were thinner with age increase. 2-year-old group's skin significantly thinner than 3 and over 4-year-old groups. However, the Jeju Pony's skin were not significantly different by age. In conclusion, the authors thought that causes of the difference of the breeds were origin and genetic differences among the horse and the pony. Furthermore, the modified umbilical herniorrhaphy with rubber rings must be used cautiously in the Jeju Pony. It should be taken into account the animals' skin thickness when the leather goods created by using their skin.