• Animal Bioscience
• /
• v.37 no.4
• /
• pp.576-590
• /
• 2024

Objective: The objective of this study was to identify genes associated with 305-day milk yield (MY) and fat yield (FY) that also influence the adaptability of the Thai multibreed dairy cattle population to tropical conditions. Methods: A total of 75,776 imputed and actual single nucleotide polymorphisms (SNPs) from 2,661 animals were used to identify genomic regions associated with MY and FY using the single-step genomic best linear unbiased predictions. Fixed effects included herd-year-season, breed regression, heterosis regression and calving age regression effects. Random effects were animal additive genetic and residual. Individual SNPs with a p-value smaller than 0.05 were selected for gene mapping, function analysis, and quantitative trait loci (QTL) annotation analysis. Results: A substantial number of QTLs associated with MY (9,334) and FY (8,977) were identified by integrating SNP genotypes and QTL annotations. Notably, we discovered 17 annotated QTLs within the health and exterior QTL classes, corresponding to nine unique genes. Among these genes, Rho GTPase activating protein 15 (ARHGAP15) and catenin alpha 2 (CTNNA2) have previously been linked to physiological traits associated with tropical adaptation in various cattle breeds. Interestingly, these two genes also showed signs of positive selection, indicating their potential role in conferring tolerance to trypanosomiasis, a prevalent tropical disease. Conclusion: Our findings provide valuable insights into the genetic basis of MY and FY in the Thai multibreed dairy cattle population, shedding light on the underlying mechanisms of tropical adaptation. The identified genes represent promising targets for future breeding strategies aimed at improving milk and fat production while ensuring resilience to tropical challenges. This study significantly contributes to our understanding of the genetic factors influencing milk production and adaptability in dairy cattle, facilitating the development of sustainable genetic selection strategies and breeding programs in tropical environments.

• Proceedings of the Zoological Society Korea Conference
• /
• 1998.10b
• /
• pp.342.2-342
• /
• 1998

No Abstract, See Full Text

• Transactions of the Korean Society of Automotive Engineers
• /
• v.12 no.3
• /
• pp.51-58
• /
• 2004

Optimization of engine desist and operation parameters using a genetic algorithm was demonstrated for direct injection diesel engine combustion. A micro genetic algorithm and a modified KIVA-3V code were used for the analysis and optimization of the engine combustion. At each generation of the optimization step the micro genetic algorithm generated five groups of parameter sets, and the five cases of KIVA-3V analysis were to be performed either in series or in parallel. The micro genetic algorithm code was also parallelized by using MPI programming, and a multi-CPU parallel supercomputer was used to speed up the optimization process by four times. An example case for a fixed engine speed was performed with six parameters of intake swirl ratio, compression ratio, fuel injection included angle, injector hole number, SOI, and injection duration. A simultaneous optimization technique for the whole range of engine speeds would be suggested for further studies.

• Proceedings of the KSME Conference
• /
• 2003.04a
• /
• pp.1639-1644
• /
• 2003

A hybrid genetic algorithm is developed for estimating the wall emissivities for an absorbing, emitting, and scattering media in a two-dimensional irregular geometry with diffusely emitting and reflecting opaque boundaries by minimizing an objective function, which is expressed by the sum of square errors between estimated and measured temperatures at only four data positions. The finite-volume method was employed to solve the radiative transfer equation for a two-dimensional irregular geometry. The results show that a developed hybrid genetic algorithms reduce the effect of genetic parameters on the performance of genetic algorithm and that the wall emissivities are estimated accurately without measurement errors.

• Journal of Microbiology
• /
• v.34 no.2
• /
• pp.166-171
• /
• 1996

Genetic analysis was conducted on newly isolated coliphages form soil by using a RAPD assay. From the initial result, the coliphages were turned out to be different form one another but were closely related to .psi..lambda. due to the fact that they shared the samed RAPD maker in which other T phage testings failed to show. By using the primers EC01 or EC02, a fast genetic mutation of .psi.C1 was found by producing specific RAPD markers on the phages from the first filial progeny to the second filial progeny. When we made a RAPD assay with combined primers (EC01, EC05 and EC08), the genetic mutation was again confirmed in .psi.C1. The assay detection showed mutations in other coliphages such as .psi.C2 and .psi.C3 by revealing specific RAPD bands among different progeny phages, where genetic instability of the coliphages in implied.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.18 no.1
• /
• pp.35-42
• /
• 1998

Eleven Italian ryegrass cultivars were examined for their genetic polymorphisms and phylogenetic relationships using randomly amplified polymorphic DNA (RAPD) markers. In RAPD analysis of 34 random primers, 96 of total 162 bands obtained from 16 primers were polymorphic and sizes of polymorphic band ranged between 0.5 and 1.5kb. Number of bands amplified per primer was varied from 3 to 16 and average number was 14.8. Phylogenetic relationship among cultivars based on the RAPD analysis was examined using UPGMA computer program. In pairwise genetic similarity test of 11 Italian ryegrass cultivars, Grazer and Orlando showed highest coefficient of genetic similarity as 0.740, whereas Marshall and Orlando was lowest as 0.438. Eleven Italian ryegrass cultivars were grouped into 3 major clusters and genetic distance of clusters ranged between 0.567 and 0.646, indicating low level of genetic variation.

• Proceedings of the Korean Society of Plant Biotechnology Conference
• /
• 2003.04a
• /
• pp.144-144
• /
• 2003

• Proceedings of the Korean Society of Plant Biotechnology Conference
• /
• 2003.04a
• /
• pp.146-146
• /
• 2003

• Proceedings of the Korean Society of Potoscience Conference
• /
• 2002.06a
• /
• pp.64-64
• /
• 2002

• Proceedings of the Zoological Society Korea Conference
• /
• 2003.08a
• /
• pp.204.3-204
• /
• 2003

No Abstract, See Full Text