• Asian-Australasian Journal of Animal Sciences
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• v.33 no.12
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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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• v.16 no.5
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• pp.748-763
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• 2003

Anaerobic rumen microorganisms mainly bacteria, protozoa and fungi degrade ligno-cellulosic feeds consumed by the ruminants. The ruminants in developing countries are predominantly maintained on low grade roughage and grazing on degraded range land resulting in their poor nutrient utilization and productivity. Hence, manipulation of rumen fermentation was tried during last two decades to optimize ruminal fermentation for improving nutrient utilization and productivity of the animals. Modification of rumen microbial composition and their activity was attempted by using chemical additives those selectively effect rumen microbes, introduction of naturally occurring or genetically modified foreign microbes into the rumen and genetically manipulation of existing microbes in the rumen ecosystem. Accordingly, rumen protozoa were eliminated by defaunation for reducing ruminal methane production and increasing protein outflow in the intestine, resulting in improve growth and feed conversion efficiency of the animals. Further, Interspecies trans-inoculation of rumen microbes was also successfully used for annulment of dietary toxic factor. Additionally, probiotics of bacterial and yeast origin have been used in animal feeding to stabilize rumen fermentation, reduced incidence of diarrhoea and thus improving growth and feed conversion efficiency of young stalk. It is envisaged that genetic manipulation of rumen microorganisms has enormous research potential in developing countries. In view of feed resource availability more emphasis has to be given for manipulating rumen fermentation to increase cellulolytic activity for efficient utilization of low grade roughage.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.9
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• pp.1337-1344
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• 2000

Differences in the physical structure and chemical composition of sorghums result in different nutritional values. Sorghums with high in vitro nutrient digestibility tend to have greater ileal and total tract nutrient digestibilies. Soft endosperm can improve growth and nutrient digestibility in nursery pigs and broiler chicks. However, finishing pigs respond less to endosperm hardness. Chicks benefit from waxy sorghums, but responses of swine to waxy sorghum remain controversial. Reduction of particle size benefits nursery pigs more than finishing pigs, while age of chicks affects the coarseness preference. Nutritional benefits of thermal processing in sorghum remain unclear in chicks and pigs. Although experiments have demonstrated increased efficiency with processed sorghum, processing provided only an immediate solution to the problem of reduced utilization. Long-term, solutions will be genetic improvement of physical and on chemical characteristic.

• Animal Systematics, Evolution and Diversity
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• v.39 no.4
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• pp.295-299
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• 2023

Two land snails, Aegista chejuensis (Pilsbry and Hirase, 1908) and Plectotropis quelpartensis (Pilsbry and Hirase, 1908), are endemic to Korea and were collected from Hataedo and Jodo Islands in the Yellow Sea of South Korea, respectively. Many terrestrial snail habitats have been confirmed in Korea; however, their genetic sequences have rarely been reported. This study describes the mitochondrial cytochrome c oxidase subunit I gene (COI) sequences of two species, followed by an analysis of the genetic distance between these two species and their congeners. As a result, there was no intra-species variation in both species A. chejuensis or P. quelpartensis. However, the inter-species variation was clear (10.3-31.5%). We provide photographs and a brief diagnosis for morphological verification.

• International Journal of Contents
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• v.2 no.1
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• pp.39-44
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• 2006

Load sharing is a critical resource in computer system. In sender-initiated load sharing algorithms, the sender continues to send unnecessary request messages for load transfer until a receiver is found while the system load is heavy. Meanwhile, in the receiver initiated load sharing algorithms, the receiver continues to send an unnecessary request message for load acquisition until a sender is found while the system load is light. These unnecessary request messages result in inefficient communications, low CPU utilization, and low system throughput in distributed systems. To solve these problems, we propose a genetic algorithm based approach for improved sender-initiated and receiver-initiated load sharing in distributed systems. And we expand this algorithm to an adaptive load sharing algorithm. Compared with the conventional sender-initiated and receiver-initiated algorithms, the proposed algorithm decreases the response time and task processing time.

• Animal Bioscience
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• v.34 no.11
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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.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.43-43
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• 2019

The collection, evaluation and conservation of crop germplasm have been treated as one of the basics to breeding program. An understanding of genetic relationships among germplasm resources is vital for future breeding process like yield, quality, and resistance. In the present study, EST-SSR markers were employed to assess the polymorphism and genetic diversity of 192 accessions of Proso millet preserved in the National Agrobiodiversity Center of RDA. We evaluated the efficiency of EST-SSR markers developed for proso millet species. A total of 98 alleles were detected with an average allele number of 4.5 per locus among 192 proso millet millet accessions using 22 EST-SSR markers. The averaged values of gene diversity ($H_E$) and polymorphism information content (PIC) for each EST-SSR marker were 0.362 and 0.404 within populations, respectively. Our results showed the moderate level of the molecular diversity among the proso millet accessions from diverse countries. A phylogenetic tree revealed three major groups of accessions that did not correspond with geographical distribution patterns with a few exceptions. The less correlation between the clusters and their geographic location might be considered due to their type difference. Our study provided a better understanding of genetic relationships among various germplasm collections, and it could contribute to more efficient utilization of valuable genetic resources. The EST-SSR markers developed here will serve as a valuable resource for genetic studies, like linkage mapping, diversity analysis, quantitative trait locus/association mapping, and molecular breeding.

• Korean Journal of Plant Resources
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• v.26 no.2
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• pp.328-335
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• 2013

The National Agrobiodiversity Center is the nodal agency assigned as the National Agricultural Genebank of the Rural Development Administration. Its main role is to collect, conserve, evaluate and distribute plant genetic resources. As of 2010, NAC has distributed a total of 380,981 accessions in the last 20 years (1991-2010) or an average of about 19,000 accessions per year. To meet customers' demands for germplasm and derive quality improvements, a mail survey in 2011 was conducted among the genetic resource users in 2010. Most of the clients obtained information on the germplasm conserved in the national genebank from the NAC website or NAC staff, and they sought specific traits in the samples. Most users received the materials within 15 days, and wanted useful data together with genetic resource. Korean landrace was the most frequently requested accessions. According to the survey results, it is supposed that useful genetic resources should be preferentially collected and their characterization/evaluation should be strengthened to enhance the utilization of genetic resources.

• Proceedings of the Korean Society of Crop Science Conference
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• 1999.11a
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• pp.145-167
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• 1999

Our self-sufficiency of food has become less than $30{\%}$ and our nation is highly dependant on world's grain market for food. which is unstable in long term due to the world population growth faster than food production. Therefore, it is a great possibility that food might become a political weapon by way of its global shortage. its purchasing difficulty in international free trade market. and the resultant price rising. Our maximal capability of food production has become the most outstanding problem in the dimension of future food security. It would be the utmost scheme for maximal production of food to realize the maximal utilization of arable land through the enlargement of sufficient farming land and the conversion of rotation system for the more grain production. Extensional enlargement of arable land can be positively executed through the development of farming land in domestic and abroad countries. The readjustment of arable land and the installation or irrigation and drainage system can enforce the farming basement for maximal utilization of arable land through the improved rotation between paddy and upland. The prevention policy against farming land encroachment should be strictly executed through grain production encouragement on resting or marginal lands and regulation of utilization conversion for the other than food production on high grade farming lands. It is also required urgently to develope high yielding and high quality varieties through advanced genetic technology for the improvement of unit area yield, especially of wheat, corn. and soybean we import in large quantity The maximal utilization of arable land for the highest production of food can be realized through rational rotation system, the most adaptable crop cultivation on the suitable land, and the most optimal fertilization through the GIS analysis of agricultural environment information on the basis of the computerized soil resource data on super detailed soil maps(1:5000) surveyed plot by plot of whole nation.

• Journal of Animal Science and Technology
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• v.58 no.2
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• pp.7.1-7.13
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• 2016

Canola meal is derived from the crushing of canola seed for oil extraction. Although it has been used in swine diets for a long time, its inclusion levels have been limited due to concerns regarding its nutritive value primarily arising from results of early studies showing negative effects of dietary canola meal inclusion in swine diets. Such effects were attributable to the presence of anti-nutritional factors (ANF; notably glucosinolates) in canola meal. However, due to advances in genetic improvements of canola that have led to production of cultivars with significantly lower ANF content and improved processing procedures, canola meal with a superior nutritive value for non-ruminant animals is now available. Therefore, the aim of this paper is to review the recent studies in the use of canola meal as feedstuff for swine, the factors influencing its use and the strategies to overcome them. First a historical overview of the development of canola is provided.