• Asian-Australasian Journal of Animal Sciences
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• 제14권4호
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• pp.587-596
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• 2001

In the last decade, rapid developments in molecular biotechnology and of genomic tools have enabled the creation of dense linkage maps across whole genomes of human, plant and animals. Successful development and implementation of interval mapping methodologies have allowed detection of the quantitative trait loci (QTL) responsible for economically important traits in experimental and commercial livestock populations. The candidate gene approach can be used in any general population with the availability of a large resource of candidate genes from the human or rodent genomes using comparative maps, and the validated candidate genes can be directly applied to commercial breeds. For the QTL detected from primary genome scans, two incipient fine mapping approaches are applied by generating new recombinants over several generations or utilizing historical recombinants with identity-by-descent (IBD) and linkage disequilibrium (LD) mapping. The high resolution definition of QTL position from fine mapping will allow the more efficient implementation of breeding programs such as marker-assisted selection (MAS) or marker-assisted introgression (MAI), and will provide a route toward cloning the QTL.

• Asian-Australasian Journal of Animal Sciences
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• 제20권3호
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• pp.453-460
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• 2007

An overview of developments important in the future of animal breeding is discussed. Examples from the application of quantitative genetic principles to selection in chickens and mice are given. Lessons to be learned from these species are that selection for production traits in livestock must also consider selection for reproduction and other fitness-related traits and inbreeding should be minimized. Short-term selection benefits of best linear unbiased predictor methodology must be weighed against long-term risks of increased rate of inbreeding. Different options have been developed to minimize inbreeding rates while maximizing selection response. Development of molecular genetic methods to search for quantitative trait loci provides the opportunity for incorporating marker-assisted selection and introgression as new tools for increasing efficiency of genetic improvement. Theoretical and computer simulation studies indicate that these methods hold great promise once genotyping costs are reduced to make the technology economically feasible. Cloning and transgenesis are not likely to contribute significantly to genetic improvement of livestock production in the near future.

• Journal of Microbiology and Biotechnology
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• 제25권4호
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• pp.431-438
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• 2015

Ever since the ban on antibiotic growth promoters (AGPs), the livestock death rate has increased owing to pathogenic bacterial infections. There is a need of developing AGP alternatives; however, the mechanisms by which AGP enhances livestock growth performance are not clearly understood. In this study, we fed 3-week-old swine for 9 weeks with and without AGPs containing chlortetracycline, sulfathiazole, and penicillin to investigate the effects of AGPs on swine gut microbiota. Microbial community analysis was done based on bacterial 16S rRNA genes using MiSeq. The use of AGP showed no growth promoting effect, but inhibited the growth of potential pathogens during the early growth stage. Our results showed the significant increase in species richness after the stabilization of gut microbiota during the post-weaning period (4-week-old). Moreover, the swine gut microbiota was divided into four clusters based on the distribution of operational taxonomic units, which was significantly correlated to the swine weight regardless of AGP treatments. Taxonomic abundance analysis indicated a negative correlation between host weight and the abundance of the family Prevotellaceae species, but showed positive correlation to the abundance of the family Spirochaetaceae, Clostridiaceae_1, and Peptostreptococcaeae species. Although no growth performance enhancement was observed, the use of AGP inhibited the potential pathogens in the early growth stage of swine. In addition, our results indicated the ecological succession of swine gut microbiota according to swine weight. Here, we present a characterization of swine gut microbiota with respect to the effects of AGPs on growth performance.

• 한국동물위생학회지
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• 제35권2호
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• pp.139-145
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• 2012

Prevalence of major legal communicable diseases in bovine and swine had been monitored in Jeonbuk province from year 2004 to 2008. At least 1 communicable disease had been reported in 687 heads from 68 bovine farms and 17 farms (25.0%) of the 68 positive farms had 1~2 additional outbreaks during the surveillance. By disease, enzootic bovine leukosis, Johne's disease and Akabane disease were occurred in 53 farms (582 heads), 14 farms (100 heads) and 1 farm (5 heads), respectively. Swine communicable diseases were occurred in 4,466 heads from 63 swine farms and 18 farms (28.6%) of the 63 positive farms had 1~2 additional outbreaks during the surveillance. By disease, Aujeszky's disease (AD), porcine epidemic diarrhea (PED), classical swine fever (CSF), porcine reproductive and respiratory syndrome (PRRS), porcine transmissible gastroenteritis (TGE), atrophic rhinitis (AR) and Japanese encephalitis in swine (JE) were occurred in 20 farms (70 heads), 20 farms (2,817 heads), 12 farms (258 heads), 6 farms (1,257 heads), 1 farm (50 heads), 1 farm (2 heads) and 1 farm (10 heads), respectively. In total, 10 communicable diseases (1 species of first-class, 3 species of second-class, and 6 species of third-class) were reported. The first-class diseases were CSF. Johne's disease, and Aujeszky's disease. JE was the second-class and Akabane disease, enzootic bovine leukosis (EBL), PED, PRRS, TGE and AR were third-class diseases.

• 한국초지조사료학회지
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• 제21권3호
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• pp.115-122
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• 2001

본 연구는 공익적인 기능을 가진 야생화 초지를 조성하고, 야생화 초지에서 생산된 초류의 건물수량과 사료가치를 조사하여 가축의 조사료원으로써의 가치를 평가하기 위해 실시하였다. 시험은 관행 혼파초지(Conventional pasture; COP, 6종), 하번 초 혼파초지(Bottomgrass pasture; BOP, turf grass 6초종), 국산 야생화 초지(Native wildflower pasture; NWP, turf grass 6종 + 국산야생화 11종) 빛 외국 산 야생화 초지(Introduced wildflower pasture; IWP, turf grass 6종 + 외국산야생화 9종) 등의 4처리를 두어 난괴법 4반복으로 시험하였다. 시험은 충남 대학교 농과대학 초지시험포장에서 1997년 8월부 터 2000년 12월까지 수행하였으며, 시험결과는 다음과 같다. 1. 야생화 초지의 3년평균 건물생산량(NWP 6,688 k kg/ha, IWP 7,240kg/ha)은 turf grass에 야생화를 도입하였던 관계로 관행 혼파초지(8,592kg/ha)나 하변 초 혼파초지(7,264kg/ha)에 비하여 건물수량이 낮게 나타났다(p<0.05). 2. 관행 혼파초지에 비하여 야생화 초지의 품질 이 상대적으로 약간 떨어지는 경향을 나타내었다. 한편, 국산 야생화 초지는 외국산 야생화 초지에 비하여 CP와 섬유소물질인 NDF, lignin은 낮은 편이었고, IVDMD는 높은 결과를 보였다. 3. 관행 혼파초지에 비하여 야생화 초지(NWP, IWP)는 토양의 pH와 교환성 Ca 함량은 낮은 편이었으나, 유기물 함량, 총 질소 함량, 인산 함량, 교환성 Mg, K 함량이 상대적으로 높아서 토양의 화학적 성분이 다소 개선되는 양상을 보였다. 이상의 결과를 종합할 때, 야생화 초지는 관행 혼파초지에 비해 건물수량, 사료가치 및 건물소화율 등이 다소 낮은 결과를 보였으나 관행 혼파초지에 비하여 일부 토양의 화학적 성분이 개선되었다. 그러나 야생화초지는 가축의 조사료 생산적인 측면보다는 공익적인 측변도 강조되기 때문에 생산성과 품질이 다소 낮더라도 의미가 있다고 하겠다.

• Journal of Animal Science and Technology
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• 제57권12호
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• pp.41.1-41.4
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• 2015

Background: The present study was intended to determine the prevalence and identification of species involved causing coccidiosis in broilers rearing under traditional farming system in Mirpur, Azad Kashmir, Pakistan. For the current study, a convenient sampling technique was carried out. A total of 7814 broilers (aged 1 to 6 weeks) were submitted to the Disease Diagnostic Laboratory of Livestock and Animal husbandry Department Mirpur, Azad Kashmir. Results: From the total screened, 750 were found positive for coccidiosis representing an overall prevalence of 9.59 %. Age-wise highest prevalence (10.88 %) recorded in the middle age birds (0 to 3 week old) were found more susceptible to infection than those aged above 3 weeks. Higher prevalence (12.49 %) of coccidiosis in broilers was observed in spring as compared with 6.60 % in summer season. In this study two main coccidiosis causing species, Emeria tenella and Emeria maxima were identified on the basis of their morphological feature and habitat (caeca and intestine), However, E. tenella was dominant compared to E. maxima. Conclusion: The study provides an insight to the occurrence of Emeria species which must be taken into consideration when rearing the broilers.

• Mycobiology
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• 제36권4호
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• pp.266-269
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• 2008

Twenty isolates of Bacillus species obtained from livestock manure composts and cotton-waste composts were tested for their antagonistic effects in vitro against three green mold pathogens of mushrooms (Trichoderma harzianum, T. koningii, and T. viridescens). However, there exists a possibility Bacillus species may have antagonistic effects against mushrooms themselves, and thus the same 20 isolates were tested in vitro against three species of mushrooms (Flammulina velutipes, Lentinus edodes, and Pleurotus ostreatus). Of the 20 Bacillus species isolates tested, two inhibited mycelial growth of T. harzianum, seven that of T. koningii, and eight that of T. viridescens. Importantly, the bacterial isolates M27 and RM29 strongly inhibited mycelial growth of all the Trichoderma spp. isolates tested. The isolate M27 was subsequently identified as the most effective in inhibiting mycelial growth of all the Trichoderma species. Interesting results of the effect Bacillus isolates had upon the mushroom species followed. It was found that most Bacillus isolates except 5T33 at least somewhat inhibited mycelial growth of the three mushroom species or some of the mushrooms. Furhermore, the antagonistic effects of the bacterial isolates against the three species of mushrooms varied depending on the mushroom species, suggesting a role for mushroom type in the mechanism of inhibition. The bacterial isolates M27 and RM29 were identified as having the most antagonistic activity, inhibiting mycelial growth of all the Trichoderma spp. as well as mycelial growth of the three species of mushrooms. These results suggest that the bacterial isolates and their antagonistic effects on green mold pathogens should be further studied for their practical use for biological control of green mold in the growing room of the mushrooms.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2016년도 춘계학술대회 및 임시총회
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• pp.33-33
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• 2016

Mycotoxins are toxic secondary metabolites produced by fungi. They can be present in where agricultural-based commodities are contaminated with toxigenic fungi. These mycotoxins cause various toxicoses in human and livestock when consumed. Small grains including corn, barley, rice or wheat are frequently contaminated with mycotoxins due to infection mainly by toxigenic Fusarium species and/or under environment favorable to fungal growth. One of the most well-known Fusarium toxin groups in cereals is trichothecenes consisting of many toxic compounds. Deoxynivalenol (DON), nivalenol (NIV), T-2 toxin, and various derivatives belong to this group. Zearalenone and fumonisin (FB) are also frequently produced by many species of the same genus. In order to monitor Korean cereals for contamination with Fusarium and other mycotoxigenic fungal species as well, barley, corn, maize, rice grains, and soybean were collected from fields at harvest or during storage for several years. The fungal colonies outgrown from the grain samples were identified based on morphological and molecular characteristics. Trichothecene chemotypes of Fusarium species or presence of FB biosynthetic gene were determined using respective diagnostic PCR to predict possible toxin production. Heavy grain contamination with fungi was detected in barley, rice and wheat. Predominant fungal genus of barley and wheat was Alternaria (up to 90%) while that of rice was Fusarium (~40%). Epicoccum also appeared frequently in barley, rice and wheat. While frequency of Fusarium species in barley and wheat was less than 20%, the genus mainly consisted of Fusarium graminearum species complex (FGSC) which known to be head blight pathogen and mycotoxin producer. Fusarium composition of rice was more diverse as FGSC, Fusarium incarnatum-equiseti species complex (FIESC), and Fusarium fujikuroi species complex (FFSC) appeared all at considerable frequencies. Prevalent fungal species of corn was FFSC (~50%), followed by FGSC (<30%). Most of FFSC isolates of corn tested appeared to be FB producer. In corn, Fusarium graminearum and DON chemotype dominate within FGSC, which was different from other cereals. Soybeans were contaminated with fungi less than other crops and Cercospora, Cladosporium, Alternaria, Fusarium etc. were detected at low frequencies (up to 14%). Other toxigenic species such as Aspergillus and Penicillium were irregularly detected at very low frequencies. Multi-year survey of small grains revealed dominant fungal species of Korea (barley, rice and wheat) is Fusarium asiaticum having NIV chemotype.

• 한국콘텐츠학회논문지
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• 제20권8호
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• pp.674-684
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• 2020

하수의 종류(생활하수, 축산폐수) 및 다양한 처리 공정에 따른 미생물군집구조를 비교하기 위해 A2O공법으로 운영되는 생활하수처리시설(안심·서부·신천)의 10개 생물학적 반응조와 축산폐수처리시설의 활성슬러지를 채취해 DNA 유전체를 추출한 후 세균은 프라이머 27F/518R, 고세균의 경우, 프라이머 Arch519F/A958R를 이용해 유전체를 증폭시켰고 그 염기서열을 Roche 454 GS-FLX Titanium을 이용한 pyrosequencing 법으로 분석하였다. 그 결과, 생활하수와 축산폐수에 따른 미생물 군집구조의 차이는 컸지만 A2O공법에 따른 산소 유무 등의 환경 변화와 관련된 군집구조의 변화는 크지 않았다. 혐기조 및 무산소조 반응조들에서만 분석한 고세균 군집 결과에서는 동일 하수처리시설의 반응조들의 고세군군집들끼리만 모이는 하수처리시설별 집괴현상을 나타냈다. 세균다양성 및 종 풍부도가 높은 서부처리시설이 다른 시설보다 더 높은 질소 및 인 제거율을 나타냈다.

• Asian-Australasian Journal of Animal Sciences
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• 제17권6호
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• pp.777-783
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• 2004

Samples of 13 species of forest tree leaves fed to livestock in the semi-hilly arid zone of Punjab State in India were collected at 30 d interval for 12 months, in order to assess their nutritional worth for livestock. The ground samples were pooled for 4 different seasons viz. dry hot, hot humid, fall and winter. The chemical composition irrespective of the season revealed that CP content varied between 8.9 (Carrisa) to 22.0% (Leucaena). Globulin was the major protein fraction in most of the leaves. The lowest concentration of cell wall constituents was observed in Morus alba and Grewea. The leaves in general became fiberous and lignified during winter and fall as compared to summer season. The leaves of Grewea, Morus alba, Leucaena, Carrisa and Acacia were rich in Ca, P and most of the trace elements. The total phenolics ranged between 1.88% (Azardirachta) to 15.82% (Acacia). The leaves of Acacia had the highest concentration of hydrolysable tannins (14.6%) whereas that of Carrisa had that of condensed tannins (5.9%). The condensed tannins (more than 3%) were negatively correlated to the digestibility of dry matter (DM), neutral detergent fiber (NDF) and crude protein (CP). The digestion kinetic parameters for DM, NDF and CP revealed that leaves of Morus alba, Zizyphus and Ehretia had highest insoluble but potentially degradable fraction. The minimum rumen fill values also revealed that leaves of Grewea, Azardirachta, Morus, Ehretia and Leucaena had great potential for voluntary DM intake. The leaves of Ougeinia, Malha, Dodenia and Carrisa had significantly higher rumen fill value indicating poor potential for voluntary DM intake. Season did not have any significant impact on digestion kinetic parameters except that most of the leaves had low potentially degradable fraction, which was degraded at slow rate during winter. It was concluded that the leaves of Morus, Ehretia, Grewea and Leucaena had great potential as livestock feed, while feeding of Ougeinia, Malha and Dodonea leaves should be avoided.