• The Korea Swine Journal
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• v.11 no.2 s.114
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• pp.133-135
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• 1989

• Journal of Ecology and Environment
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• v.30 no.4
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• pp.315-318
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• 2007

Cooperative or non-territorial permanently social spiders are believed to have evolved from species showing subsocial maternal care. The transition from subsocial to cooperative social groups probably involved a transition from an outbreeding breeding system to one with inbreeding. Nepotistic recognition among siblings should facilitate the evolution of social cooperation through avoidance of inbreeding and maintenance of mutual tolerance between siblings. We conducted experiments to determine whether a mechanism for sibling recognition is present in the subsocial spider, Coelotes terrestris which displays extended maternal care in the form of food provisioning. The numbers of surviving individuals within unfed groups were observed and compared between non-sibling groups of ten spiderlings and groups of ten siblings. The number of survivors differed significantly between groups, with consistently fewer spiderlings surviving in the non-sibling groups than the sibling groups over the study period. This result suggests that sibling recognition and nepotism do occur in this subsocial species. The nepotism involved in the maternal social organization of the Coelotes might be an example of a preadaptation facilitating the evolution of permanent social life.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.938-942
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• 2006

Genetic diversity of Magra - a lustrous carpet wool breed of India, was investigated by means of 25 ovine microsatellite markers proposed by the Food and Agriculture Organization and the International Society for Animal Genetics (FAO-ISAG). All used microsatellites amplified well and exhibited polymorphisms. A wide range of genetic variability was observed as allele number from 3 (BM6506, OarCP20) to 10 (CSSM31), observed heterozygosity from 0.200 (BM6506) to 0.947 (OarHH35), expected heterozygosity from 0.368 (CSSM47) to 0.864 (BM1314) and Polymorphism Information Content (PIC) from 0.347 (CSSM47) to 0.849 (BM1314). This supported the utility of these microsatellite loci in the measurement of genetic diversity indices in Indian sheep too. Various average genetic variability measures viz., allele diversity (5.7), observed heterozygosity (0.597), expected heterozygosity (0.694) and mean PIC (0.648) values showed high genetic variability despite accumulated inbreeding as reflected by the high average inbreeding coefficient ($F_{IS}=0.159$) due to the unequal sex ratio of the breeding animals.

• Animal cells and systems
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• v.9 no.1
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• pp.27-35
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• 2005

Bupleurum euphorbioides is isolated and restricted to high mountains in Korea northeastern China. Its conservation depends on whether it is threatened by inbreeding or a loss of genetic diversity. We compared the genetic variability in B. euphorbioides with B. longiradiatum, a widespread congener, to understand how they differ in their population genetic structure. Although B. euphorbioides showed a little lower genetic variability than B. longiradiatum, $F_{IS}$ statistics for most loci were strongly positive in both B. euphorbioides (0.445) and B. longiradiatum (0.553). In addition, B. euphorbioides showed higher mean $F_{ST}$ value than B. longiradiatum (0.297 vs 0.194). It might be due to the polycarpic nature of B. longiradiatum, which holds higher genetic potentials effectively in homogeneous environment than the monocarpic B. euphorbioides. The results suggested that B. euphorbioides is a genetically viable species, and that they are threatened primarily by environmental factor.

• Journal of Ecology and Environment
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• v.30 no.3
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• pp.225-229
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• 2007

The mating systems of natural populations of Potentilla freyniana in Korea were determined using allozyme analysis. The result suggests that P. freyniana is outcrossing as well as employing vegetative reproduction by stolon (self-fertilization rate, s < 0.5). The values of the inbreeding coefficient of eight populations in Korea varied from 0.244 to 0.331, with an average value of 0.274. For eight natural populations, multi-locus estimates of outcrossing (tm) was 0.603 across 13 polymorphic loci, with individual population values ranging from 0.530 to 0.652. The relatively low outcrossing rates of some populations could be attributed to extensive vegetative reproduction by stolon and the isolation of flowering mature plants. Although P. freyniana usually propagated by asexually-produced ramets, I could not rule out the possibility that sexual reproduction occurred at a low rate because each ramet may produce terminal flowers. Although heterozygote excess was observed in some natural populations, most populations exhibited varying degrees of inbreeding and a heterozygote deficit.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.4
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• pp.463-467
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• 2006

Genetic profiles of Iranian Holstein young bulls at the national artificial insemination station were determined on the basis of individual genotypes at 13 ISAG's recommended microsatellites, the most useful markers of choice for parentage identification. In the present study a total of 119 individuals were genotyped at 13 microsatellite loci and for possible parent-offspring combinations. A high level of genetic variation was evident within the investigated individuals as assessed from various genetic diversity measures. The mean number of observed alleles per microsatellite marker was 9.15 and the number of effective alleles as usual was less than the observed values (4.03). The average observed and expected heterozygosity values were 0.612 and 0.898, respectively. The mean polymorphic information content (PIC) value (0.694) further reflected a high level of genetic variability. The average exclusion of probability (PE) of the 13 markers was 0.520, ranging from 0.389 to 0.788. The combined exclusion of probability was 0.999, when 13 microsatellite loci were used for analysis in the individual identification system. Inbreeding was calculated as the difference between observed and expected heterozygosity. Observed homozygosity was less than expected which reflects inbreeding of -3.7% indicating that there are genetic differences between bull-sires and bull-dams used to produce young bulls. The results obtained from this study demonstrate that the microsatellite DNA markers used in the present DNA typing are useful and sufficient for individual identification and parentage verification without accurate pedigree information.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.2
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• pp.212-218
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• 2020

Objective: Agu pigs are indigenous to the Okinawa prefecture, which is the southernmost region of Japan. Agu pigs were exposed to a genetic bottleneck during the 20th century, due to the introduction of European pig breeds. The objective of this study was to elucidate the genetic structure of Agu pigs and to determine their relationships with those of five European breeds, two Chinese breeds and Ryukyu wild boar using microsatellite markers. Methods: A total of 203 DNA samples from 8 pig breeds were used in this study. Genotyping was performed using 21 microsatellite markers distributed across 17 chromosomes. Results: Numbers of effective alleles in Agu pigs were fewer than in European breeds and Ryukyu wild boar. Among domestic pigs, Agu pigs had the lowest heterozygosity (0.423) and highest inbreeding coefficient (F_IS = 0.202), indicating a severe loss of heterozygosity in Agu pigs possibly due to inbreeding. Neighbor-joining tree analysis was performed based on Reynolds' genetic distances, which clustered Agu pigs with Duroc pigs. However, principal component analysis revealed a unique genetic position of the Agu pig, and the second principal component separated Agu pigs from all other breeds. Structure analysis with the optimal assumption of seven groups (K = 7) indicated that Agu pigs form an independent cluster from the other breeds. In addition, high and significant F_ST values (0.235 to 0.413) were identified between Agu pigs and the other breeds. Conclusion: This study revealed a substantial loss of genetic diversity among Agu pigs due to inbreeding. Our data also suggest that Agu pigs have a distinctive genetic structure, although gene flows from European breeds were observed.

• Journal of Mushroom
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• v.1 no.1
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• pp.9-14
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• 2003

To breed new superior strains, collected strains were characterized and then several white strains were selected as parents. Monokaryons from the parents were isolated and studied. All tested white strains showed same mating genotype. Growth rate of monokaryons were lower than collected dikaryons. New dikaryotic strains were derived from inbreeding method, which means mating between monokaryotic isolates from different white strains having same mating genotype. Some of them showed higher yields of fruitbody than their parents. Specially Fv 4-1 strain showed the best productivity. Furthermore some mating combination showed cytoplasmic effect, when they mated reciprocally.

• Korean Journal of Poultry Science
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• v.44 no.2
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• pp.75-81
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• 2017

A total of 340 individuals from seven duck populations were studied using 24 polymorphic microsatellite (MS) markers to identify plumage colors with genetic diversity. The estimated average number of alleles (Na), polymorphic information content (PIC) value, and expected heterozygosity (He) per locus of all populations were 11.5, 0.602, and 0.635, respectively. The calculated population genetic distance (Fst), inbreeding coefficient of individuals within duck populations (Fis), and total inbreeding among populations (Fit) were 0.135, 0.105, and 0.229, respectively. Statistical analyses for each population using 24 marker combinations, revealed that the estimated average number of effective alleles (Ne), observed heterozygosity (Ho), and fixation index of inbreeding within populations (F) were 3.129, 0.505, and 0.104, respectively. The results of genetic distance and phylogenetic analysis revealed that Korean native duck populations were clearly separated from all Bangladeshi duck populations. Moreover, all populations clustered well according to their genetic distance, but could not be clearly separated according to black and white plumage colors or plumage color pattern. The combination of these 24 MS markers can be used for discrimination and determination of the genetic diversity of native duck breeds in further investigations for conservation and special development purposes.

• Animal Bioscience
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• v.36 no.10
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• pp.1508-1516
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• 2023

Objective: To carry out a comprehensive production planning of the existing Rongchang pig population from both environmental and genetic aspects, and to establish a closed population with stable genetic diversity and strict pathogen control, it is necessary to fully understand the genetic background of the population. Methods: We genotyped 54 specific pathogen free (SPF) Rongchang pigs using the Zhongxin-1 Porcine Breeding Array PLUS, calculated their genetic diversity parameters and constructed their families. In addition, we also counted the runs of homozygosity (ROH) of each individual and calculated the value of inbreeding coefficient based on ROH for each individual. Results: Firstly, the results of genetic diversity analysis showed that the effective population size (N_e) of this population was 3.2, proportion of polymorphic markers (P_N) was 0.515, desired heterozygosity (H_e) and observed heterozygosity (H_o) were 0.315 and 0.335. H_o was higher than H_e, indicating that the heterozygosity of all the selected loci was high. Secondly, combining the results of genomic relatedness analysis and cluster analysis, it was found that the existing Rongchang pig population could be divided into four families. Finally, we also counted the ROH of each individual and calculated the inbreeding coefficient value accordingly, whose mean value was 0.09. Conclusion: Due to the limitation of population size and other factors, the genetic diversity of this Rongchang pig population is low. The results of this study can provide basic data to support the development of Rongchang pig breeding program, the establishment of SPF Rongchang pig closed herd and its experimental utilization.