• 한국수산과학회지
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• 제42권6호
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• pp.600-603
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• 2009

Genetic and phenotypic parameter estimates for measurement traits were obtained from pacific oyster Crassostrea gigas at nine months old. For the growth-related traits among nine months old pacific oyster, heritabilities of shell length, shell height, shell width, total weight, body weight and shell weight were estimated as 0.4855, 0.5248, 0.0884, 0.7236, 0.7726 and 0.6957, respectively. Genetic correlations among the growth-related traits of pacific oyster at nines month old, shell length, shell height, shell width, total weight, body weight, shell weight were showing highly positive correlations. Breeding value on growth-related traits of pacific oyster at nine months old were estimated as shell length -7.044-11.870, shell height -11.380-18.370, shell width -1.234-2.831, total weight -8.339-17.140, body weight -1.813-3.507 and shell weight -4.422-8.837. The results show that there is quite substantial additive genetic variance for measurement traits in pacific oyster that can be exploited through selective breeding.

• Asian-Australasian Journal of Animal Sciences
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• 제20권5호
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• pp.633-637
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• 2007

Genetic variation in Nilagiri sheep, the only apparel wool breed in South India was studied using 25 FAO recommended ovine-specific microsatellite markers. The number of observed alleles ranged from 3 to 8 with a mean of 5 across all loci. The size of alleles ranged from 72 to 228 bp. The frequency of alleles ranged from 0.0104 to 0.5781. In total, 125 alleles were observed at the 25 loci studied. The effective number of alleles ranged from 2.18 to 6.49. The mean number of effective alleles was 3.84 across all loci. All the 25 loci were found to be highly polymorphic. The PIC values ranged from 0.4587 to 0.8277 with a mean of 0.6485. Of 25 microsatellites studied, 17 were in Hardy-Weinberg Equilibrium proportions. The observed heterozygosity ranged from 0.4222 to 1.000 with a mean value of 0.7610 whereas the expected heterozygosity ranged from 0.5415 to 0.8459 with a mean value of 0.7213. Except six loci, the other loci revealed negative within-population inbreeding estimates (FIS) indicating excess of heterozygotes in the population of Nilagiri sheep.

• The Korean Journal of Ecology
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• 제28권1호
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• pp.1-6
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• 2005

This study was conducted to develop the predictive model for species richness of breeding birds by multivariate analysis of land covers (percentage value of each cover in 300 $\times$ 300m grid) including water area (WA), urbanized area (UA), green area (GA), forest area (FA) and agricultural area (AA) at Seongnam City in Korea. Fifty-nine species of birds were mapped on 155 grids in size of 300 $\times$ 300 m from 2000 to 2001. Species richness of breeding birds was significantly regressed ($R^2=0.85$, n=155) by estimates of WA ($4.59{\pm}1.13$, P<0.0001), UA ($6.50{\pm}0.86$, P<0.0001), GA ($7.11{\pm}1.25$, P<0.0001), FA ($8.51{\pm}0.62$, P<0.0001), and AA ($4.59{\pm}1.13$, P<0.0001). In validation of model, the results show no significant difference between predicted value of species richness and observed one. Developed model can be used as a predictive model of species richness of birds for selecting the proper location of corridors and parks in urban area.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 춘계학술대회
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• pp.61-61
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• 2019

In any crop breeding program Selection and use of genetically diverse genotypes to develop cultivars with a broad genetic base is important. Molecular markers play a major role in selecting diverse genotypes. Molecular breeding programs of the crop can be made more efficient by use of molecular markers. The present study was done with an aim of analyzing genetic diversity and the population structure in 24 accessions of sunflower (Helianthus annus L.) from Kenya genetic diversity using 35 EST-SSR and gSSR primers.Out of the 35 markers 3 were not polymorphic as they indicated Polymorphic Information content( PIC) of value 0.00 and so the data analysis was done using 32 markers . The 32 set of markers used produced 29 alleles ranging from 2 to 7with a mean of 3.0 alleles per locus.The average value of polymorphic information contents(PIC) were 0.3 .Genetic diversity analysis using these markers revealed 3 major clusters. This result could be useful for designing strategies to make elite hybrid and inbreeding of crossing block for breeding and future molecular breeding programs to make elite variety.

• Asian-Australasian Journal of Animal Sciences
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• 제28권7호
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• pp.943-950
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• 2015

Heat stress has adverse effects on fertility of dairy animals. Decline in fertility is linearly associated with an increase in combination of both temperature and humidity. The purpose of this study was to investigate the relationship between temperature humidity index (THI) and the pregnancy rate of Murrah buffaloes in a subtropical climate. The effects of genetic and non-genetic factors viz., sire, parity, period of calving and age group at first calving were found non-significant on pregnancy rate. The effect of THI was found significant (p<0.001) on pregnancy rate of Murrah buffaloes calved for first time and overall pregnancy rate. The threshold THI affecting the pregnancy rate was identified as THI 75. The months from October to March showed THI<75 and considered as non heat stress zone (NHSZ), while months from April to September were determined as heat stress zone (HSZ) with $THI{\geq}75$. The lowest overall pregnancy rate (0.25) was obtained in July with THI 80.9, while the highest overall pregnancy rate (0.59) was found in November with THI 66.1. May and June were identified as critical heat stress zone (CHSZ) within the HSZ with maximum decline (-7%) in pregnancy rate with per unit increase in THI. The highest overall pregnancy rate was estimated as 0.45 in NHSZ with THI value 56.7 to 73.2. The pregnancy rate was found to have declined to 0.28 in HSZ with THI 73.5 to 83.7. However, the lowest pregnancy rate was estimated as 0.27 in CHSZ with THI value 80.3 to 81.6.

• Asian-Australasian Journal of Animal Sciences
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• 제24권2호
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• pp.162-172
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• 2011

In this paper, simulation was used to determine accuracies of genomic breeding values for polygenic traits associated with many thousands of markers obtained from high density genome scans. The statistical approach was based upon stochastically simulating a pedigree with a specified base population and a specified set of population parameters including the effective and noneffective marker distances and generation time. For this population, marker and quantitative trait locus (QTL) genotypes were generated using either a single linkage group or multiple linkage group model. Single nucleotide polymorphism (SNP) was simulated for an entire bovine genome (except for the sex chromosome, n = 29) including linkage and recombination. Individuals drawn from the simulated population with specified marker and QTL genotypes were randomly mated to establish appropriate levels of linkage disequilibrium for ten generations. Phenotype and genomic SNP data sets were obtained from individuals starting after two generations. Genetic prediction was accomplished by statistically modeling the genomic relationship matrix and standard BLUP methods. The effect of the number of linkage groups was also investigated to determine its influence on the accuracy of breeding values for genomic selection. When using high density scan data (0.08 cM marker distance), accuracies of breeding values on juveniles were obtained of 0.60 and 0.82, for a low heritable trait (0.10) and high heritable trait (0.50), respectively, in the single linkage group model. Estimates of 0.38 and 0.60 were obtained for the same cases in the multiple linkage group models. Unexpectedly, use of BLUP regression methods across many chromosomes was found to give rise to reduced accuracy in breeding value determination. The reasons for this remain a target for further research, but the role of Mendelian sampling may play a fundamental role in producing this effect.

• Animal Bioscience
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• 제34권11호
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• pp.1757-1765
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• 2021

Objective: The swine leukocyte antigen (SLA) gene group, which is closely linked and highly polymorphic, has important biomedical significance in the protection and utilization of germplasm resources. However, genetic polymorphism analyses of SLA microsatellite markers in Chinese miniature pigs are limited. Methods: Eighteen pairs of microsatellite primers were used to amplify the SLA regions of seven miniature pig breeds and three wild boar breeds (n = 346) from different regions of China. The indexes of genetic polymorphism, including expected heterozygosity (He), polymorphic information content (PIC), and haplotype, were analyzed. The genetic differentiation coefficient (Fst) and neighbor-joining methods were used for cluster analysis of the breeds. Results: In miniature pigs, the SLA I region had the highest numbers of polymorphisms, followed by the SLA II and SLA III regions; the region near the centromere had the lowest number of polymorphisms. Among the seven miniature pig breeds, Diannan small-ear pigs had the highest genetic diversity (PIC value = 0.6396), whereas the genetic diversity of the Hebao pig was the lowest (PIC value = 0.4330). The Fst values in the Mingguang small-ear, Diannan small-ear, and Yunnan wild boars were less than 0.05. According to phylogenetic cluster analysis, the South-China-type miniature pigs clustered into one group, among which Mingguang small-ear pigs clustered with Diannan small-ear pigs. Haplotype analysis revealed that the SLA I, II, and III regions could be constructed into 13, 7, and 11 common haplotypes, respectively. Conclusion: This study validates the high genetic diversity of the Chinese miniature pig. Mingguang small-ear pigs have close kinship with Diannan small-ear pigs, implying that they may have similar genetic backgrounds and originate from the same population. This study also provides a foundation for genetic breeding, genetic resource protection, and classification of Chinese miniature pigs.

• Animal Bioscience
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• 제34권1호
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• pp.12-19
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• 2021

Objective: The objectives of the current study were to study the main environmental factors affecting birth weight (BW) and weaning weight (WW), estimate variance components, genetic parameters and genetic trend and to evaluate the variability and relationships among breeding value of BW and WW using principal components analysis (PCA). Methods: A total of 16,370 records were collected from 8,271 buffalo calves. Genetic parameters and breeding values were estimated using a bivariate animal model which includes direct, maternal and permanent maternal effects. These estimates were standardized and used in PCA. Results: The direct heritability estimates were 0.06 and 0.41 for BW and WW, respectively whereas direct maternal heritability values were 0.03 and 0.14, respectively. Proportions of variance due to permanent environmental effects of dam were 0.455 and 0.280 for BW and WW respectively. The genetic correlation between BW and WWs was weak approaching zero, but the maternal correlation was 0.26. The first two principal components (PC1 and PC2) were estimated utilizing the standardized breeding values according to Kaiser method. The total variance explained by the first two PCs was 71.17% in which 45.91% and 25.25% were explained by PC1 and PC2, respectively. The direct breeding values of BW were related to PC2 but those of WW and maternal breeding values of BW and WWs were associated with PC1. Conclusion: The results of genetic parameters and PCA indicate that BW and WWs were not genetically correlated and improving growth traits of Egyptian buffaloes could be achieved using WW without any adverse effect by BW.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.73-73
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• 2017

To set an optimal harvest time of main 7 whole crop silage rice cultivars, Nokyang(Ny), Mogwoo(Mw), Mogyang(My), Jungmo1029(Jm1029), Jungmo1038(Jm1038), Nokwoo(Nw) and Yeongwoo(Yw), based on feed value, we analyzed their feed values such as percent crude protein(CP), crude fat(CF), crude ash(CA), neutral detergent fiber(NDF), acid detergent fiber(ADF) and lignin. It was evaluated every 10 days from heading to 40 days after heading(DAH). Total digestible nutrient(TDN) and relative feed value(RFV) was also calculated from ADF and NDF. As results, CP was generally in decline as increasing DAH in Ny, My, Jm1029, Jm1038 and Yw and decreased to 20 DAH in Mw, decreased after increasing to 30 days in Nw. The CP content of Ny was relatively the highest ranged from 5.3% to 10.1% and Mw the lowest 4.5% to 5.2%, compared to others. CF content tend to decrease as DAH increase in Ny, My and Nw and decreased after increasing to 30 days Jm1029, increased after decreasing to 20 days Jm1038 but was not shown distinct trend of increase or decrease in Mw. Especially, that of Yw's CF gradually increased as harvest time late but relative content the lowest from 1.46% to 2.29% among 7 cultivars. The CA content of Ny, My, Jm1029 and Jm1038 approximately decreased as DAH increased and that of Mw was similar to others after heading, Nw decreased after 10 days and Yw increased after flowering. In all 7 cultivars, NDF and ADF had a tendency to decrease as days accumulated, in particular, Yw was the lowest on 30 DAH and so the content of Yw's TDN the highest(71.5%), while the lowest(67.2%) in Nw. For lignin, particularly, Mw tend to be in decline as DAH increase and was the lowest ranged from 1.34% to 1.87%. ADF analyses allows for the evaluation of in vivo digestible dry matter(DDM) and energy availability and NDF analyses provides the best indication of dry matter intake(DMI). Ultimately, the two factors can be combined to derive RFV for forage. RFV in general increased as DAH increased in all cultivars and was in order, Yw>My>Ny> Jm1038>Mw>Jm1029>Nw on 30 DAH. Taken together when these results, despite a slight increase of TDN after 30 DAH except Yw, considering forage yield potential, digestibility of grains and gradual decrease of CP and CF, the yellow ripe stage, about 30 DAH, was appropriate to harvest whole crop rice for silage use.

• 한국전통조경학회지
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• 제41권4호
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• pp.40-48
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• 2023

본 연구는 국내 서·남해안 도서(島嶼) 및 연안 지역을 번식의 근거지로 활동하는 조류와 관련한 번식지 적합성 지수 개발을 위한 기초연구의 일환으로, FGI(Focus Group Interview)와 AHP(Analytic Hierarchy Process) 분석을 실시하였으며, 그 결과는 다음과 같다. 첫째, 연안성 조류 번식지 적합성 가치 판단 결과 자연적 가치(0.763)가 인위적 가치(0.237)에 비해 높은 중요도를 나타냈다. 번식공간의 지속적 완전성 담보를 위한 '보호구역 지정여부'를 제외한 다른 인위적 가치는 하위순위로 파악되었다. 둘째, 2차례 진행된 FGI에서 분류된 25개의 평가항목을 상위개념으로 재정립한 결과, 자연적 가치가 9개, 인위적 가치가 5가지, 총 14개로 최종 선정되었다. 셋째, 연안성 조류 번식지 적합성 중요도의 중분류 평가 결과는 '생태적 가치(0.392)', '지형적 가치(0.251)', '소극적 간섭(0.124)', '지질적 가치(0.120)', '적극적 간섭(0.113)'의 순서로 파악되었다. 이는 번식공간 자체의 수용적 환경보다는 번식을 위한 생존환경에 우선한 것으로 판단된다. 넷째, 연안성 조류 번식지의 평가항목 우선순위 결과는 '식생분포(0.187)', '갯벌의 면적(0.118)', '갯벌의 유무(0.092)', '천적의 출현(0.087)', '보호구역 지정여부(0.08)', '섬 면적(0.069)', '과번식에 의한 황폐화(0.064)', '토양 구성비(0.056)', '육지와의 거리(0.054)', '해양 양식장 면적(0.045)', '경작지 면적(0.041)', '경작 행위(0.038)', '표면의 각도(0.036)', '토지이용(0.033)'의 순으로 나타났다. 본 연구에서 도출된 평가항목의 가중치 결과값은 연안성 조류 번식지 공간에 집중한 우선순위 평가에 활용이 가능할 것으로 판단된다. 그러나 조류 개체가 갖는 고유의 서식지 적합성과의 상관성 여부는 보완이 필요한 것으로 보이며, 추후 종별특성을 접목한 공간분석연구는 추후 과제로 남기고자 한다.