• 한국축산식품학회지
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• 제37권3호
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• pp.368-375
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• 2017

Clostridium difficile infection (CDI) is the main cause of hospital-acquired diarrhea that can cause colitis or even death. The medical-treatment cost and deaths caused by CDI are increasing annually worldwide. New approaches for prevention and treatment of these infections are needed, such as the use of probiotics. Probiotics, including Bifidobacterium spp. and Lactobacillus, are microorganisms that confer a health benefit to the host when administered in adequate amounts. The effect of Bifidobacterium longum ATCC 15707 on infectious disease caused by C. difficile 027 was investigated in a mouse model. The survival rates for mice given the pathogen alone, and with live cells, or dead cells of B. longum were 40, 70, and 60%, respectively. In addition, the intestinal tissues of the B. longum-treated group maintained structural integrity with some degree of damage. These findings suggested that B. longum ATCC 15707 has a function in repressing the infectious disease caused by C. difficile 027.

• 대한수의학회지
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• 제57권1호
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• pp.37-42
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• 2017

Getah virus (GETV) infection causes sporadic outbreaks of mild febrile illness in horses and reproductive failure in pigs. In this study, we established a reverse transcription polymerase chain reaction (RT-PCR) method to detect GETV from suspected virus-infected samples. The reaction conditions were optimized and validated by using RNA extracted from GETV propagated in cell culture. A GETV-specific GED4 primer set was designed and used to amplify a 177 bp DNA fragment from a highly conserved region of the E1 glycoprotein gene in the GETV genome. RT-PCR performed with this primer set revealed high sensitivity and specificity. In the sensitivity test, the GED4 primer set detected GETV RNA at the level of $10^{2.0}\;TCID_{50}/mL$. In the specificity test, the GED4 primer set amplified only a single band of PCR product on the GETV RNA template, without non-specific amplification, and exhibited no cross-reactivity with other viral RNAs. These results suggest that this newly established RT-PCR method is useful for accurate identification of GETV infection in animals.

• 한국동물위생학회지
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• 제35권2호
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• pp.105-109
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• 2012

Apoptosis is a host defense mechanism that the cell uses to limit production of infectious pathogens. Although many bacteria, viruses and parasites can induce apoptosis in infected cells, some pathogens usually exhibit the ability to suppress the induction of apoptosis in the infected cells. Sophisticated evasion strategies of obligate intracellular parasites, in particular prevention of host cell apoptosis, are necessary to ensure successful replication. To study the ability of Eimeria tenella in this regard, in vitro experiments were performed applying Madin-Darby bovine kidney (MDBK) cells as host cell. We have demonstrated that productive infection of adherent cell lines by E. tenella resulted in an anti-apototic effect. This phenomenon was confirmed using in situ terminal deoxynucleotidyl transferase-mediated (TdT) deoxyuridine triphosphates (dUTP)-fluorescein nick end labeling (TUNEL) assay to detect apoptosis. Therefore, E. tenella could complete its cycle of productive infection while inducing anti-apoptosis in the infected cells. This finding might have implications for the pathobiology of E. tenella and other Eimeria species.

• Asian-Australasian Journal of Animal Sciences
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• 제30권9호
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• pp.1332-1339
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• 2017

Objective: This study investigated the effects of Bacillus subtilis CSL2 (B. subtilis CSL2) administration before Salmonella challenge on the fecal microbiota and microbial functionality of Hy-line Brown (HLB) laying hens. Methods: Fecal samples were collected from control (CON), Salmonella-infected (SAL) and Salmonella-infected, probiotic-treated (PRO) groups before and after Salmonella challenge for microbiome analysis using 16S rRNA gene pyrosequencing. Results: Infection with Salmonella led to decreased microbial diversity in hen feces; diversity was recovered with Bacillus administration. In addition, Salmonella infection triggered significant alterations in the composition of the fecal microbiota. The abundance of the phylum Firmicutes decreased while that of Proteobacteria, which includes a wide variety of pathogens, increased significantly. Bacillus administration resulted in normal levels of abundance of Firmicutes and Proteobacteria. Analysis of bacterial genera showed that Salmonella challenge decreased the population of Lactobacillus, the most abundant genus, and increased populations of Pseudomonas and Flavobacterium genera by a factor of 3 to 5. On the other hand, Bacillus administration caused the abundance of the Lactobacillus genus to recover to control levels and decreased the population of Pseudomonas significantly. Further analysis of operational taxonomic units revealed a high abundance of genes associated with two-component systems and secretion systems in the SAL group, whereas the PRO group had more genes associated with ribosomes. Conclusion: The results of this study indicate that B. subtilis CSL2 administration can modulate the microbiota in HLB laying hens, potentially acting as a probiotic to protect against Salmonella Gallinarum infection.

• 대한수의학회지
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• 제52권1호
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• pp.19-24
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• 2012

This paper describes the epidemiological characteristics of bovine brucellosis in Korea during January 2000~September 2004, which encompasses the period when the incidence of bovine brucellosis increased abruptly. Data from the National Animal Infectious Disease Data Management System were used for this study. A range of epidemiological measures was calculated including annual herd and animal incidence. During the study period, there were 1,183 outbreaks on 638 farms. In beef cattle, annual herd incidence increased from 0.2 (2000) to 11.5 (2004, to September) outbreaks per 10,000 and annual animal incidence varied between 3.4 (2000) and 105.8 (2004, to September) per 100,000, respectively. On 401 (62.9%) infected farms during this period, infection was eradicated without recurrence. Recurrence of infection was significantly higher on farms where abortion was reported (53.3%), compared to farms where it was not (30.0%). On beef cattle farms, infection was introduced most frequently through purchased cattle (46.2%). Based on the results of this study, the establishment and spread of brucellosis in the Korean beef cattle population were mainly due to incomplete or inappropriate treatment of aborted materials and the movement of infected cattle.

• Asian-Australasian Journal of Animal Sciences
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• 제14권2호
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• pp.276-279
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• 2001

The effect of helminthiasis on zinc metabolism was monitored using endogenous $^{65}Zn$ after intraperitoneal injection of 1 g of $^{65}Zn$ as zinc chloride. In the first experiment zinc turnover was investigated in 18 male weanling rats, which were randomly divided into 3 groups. One group was infected with 73 third stage larvae of Nippostrongylus brasiliensis per gram body weight ; the other groups were the pair-fed and ad lib-fed controls. The route of loss of zinc was investigated in the second experiment with the same design using 18 animals with a lower dose of infection (33 larvae per gram body weight). The biological half life of endogenous $^{65}Zn$ was lower (p<0.05) in the infected group as compared to the controls. In the later phase of infection (9th to 16th day) there was reduced retention of $^{65}Zn$ and increased loss (p<0.05) of $^{65}Zn$ from the body though urine and faeces. It was concluded that infection of N. brasiliensis was accompanied by increased loss of endogenous Zn through faeces and urine.

• 한국초지조사료학회지
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• 제37권1호
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• pp.44-49
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• 2017

본 시험은 중부지역에서 사료용 옥수수의 검은줄오갈병 발생이 조사료 생산성 에 미치는 영향을 조사하기 위하여 2006년부터 2008년까지 충청남도 천안에서 수행되었다. 사료용 옥수수의 공시품종은 국내에서 재배되고 있는 10품종으로 하였고, 재배방법은 4월 하순에 파종하는 1모작 재배와 5월 중하순에 파종하는 2모작 재배로 나누어 재배하였으며, 품종별 검은줄오갈병의 발생률과 수량성을 조사하였다. 우리나라 중부지역에서 사료용 옥수수의 품종별 검은줄오갈병의 발생률은 차이가 있었다(p<0.05). 검은줄오갈병에 강한 품종은 광안옥, P3156, 광평옥 및 P3394 품종이었고 약한 품종은 'NC+7117', '수원19호' 'DK697' 및 'GW6959' 품종이었다. 검은줄오갈병 발생에 따른 사료용 옥수수의 조사료 건물수량은 품종 간에 차이가 있었으며(p<0.05), 검은줄오갈병 발생이 많았던 수원 19호와 GW6959 품종의 건물수량이 검은줄오갈병 발생이 적었던 광평옥과 P3156 품종보다 20% 정도 적었다. 옥수수의 품종별 암이삭 비율은 검은줄오갈병 발생이 많았던 NC+7117 및 GW6959 품종이 약 29%로 가장 낮았고 검은줄오갈병의 발생이 적었던 광평옥, P3394 및 P3156 품종에서는 각각 34.0, 38.7 및 36.4%으로 높은 경향이었다. 따라서 우리나라 중부지역에서 사료용 옥수수를 재배할 때는 검은줄오갈병에 강한 품종을 선택하고 파종시기의 조절이 매우 중요하다 할 것이다.

• Journal of Veterinary Science
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• 제23권1호
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• pp.2.1-2.18
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• 2022

Background: Co-infections of the porcine reproductive and respiratory syndrome virus (PRRSV) and the Haemophilus parasuis (HPS) are severe in Chinese pigs, but the immune response genes against co-infected with 2 pathogens in the lungs have not been reported. Objectives: To understand the effect of PRRSV and/or HPS infection on the genes expression associated with lung immune function. Methods: The expression of the immune-related genes was analyzed using RNA-sequencing and bioinformatics. Differentially expressed genes (DEGs) were detected and identified by quantitative real-time polymerase chain reaction (qRT-PCR), immunohistochemistry (IHC) and western blotting assays. Results: All experimental pigs showed clinical symptoms and lung lesions. RNA-seq analysis showed that 922 DEGs in co-challenged pigs were more than in the HPS group (709 DEGs) and the PRRSV group (676 DEGs). Eleven DEGs validated by qRT-PCR were consistent with the RNA sequencing results. Eleven common Kyoto Encyclopedia of Genes and Genomes pathways related to infection and immune were found in single-infected and co-challenged pigs, including autophagy, cytokine-cytokine receptor interaction, and antigen processing and presentation, involving different DEGs. A model of immune response to infection with PRRSV and HPS was predicted among the DEGs in the co-challenged pigs. Dual oxidase 1 (DUOX1) and interleukin-21 (IL21) were detected by IHC and western blot and showed significant differences between the co-challenged pigs and the controls. Conclusions: These findings elucidated the transcriptome changes in the lungs after PRRSV and/or HPS infections, providing ideas for further study to inhibit ROS production and promote pulmonary fibrosis caused by co-challenging with PRRSV and HPS.

• Journal of Animal Science and Technology
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• 제65권4호
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• pp.838-855
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• 2023

The highly pathogenic avian influenza (HPAI) virus triggers infectious diseases, resulting in pulmonary damage and high mortality in domestic poultry worldwide. This study aimed to analyze miRNA expression profiles after infection with the HPAI H5N1 virus in resistant and susceptible lines of Ri chickens.For this purpose, resistant and susceptible lines of Vietnamese Ri chicken were used based on the A/G allele of Mx and BF2 genes. These genes are responsible for innate antiviral activity and were selected to determine differentially expressed (DE) miRNAs in HPAI-infected chicken lines using small RNA sequencing. A total of 44 miRNAs were DE after 3 days of infection with the H5N1 virus. Computational program analysis indicated the candidate target genes for DE miRNAs to possess significant functions related to cytokines, chemokines, MAPK signaling pathway, ErBb signaling pathway, and Wnt signaling pathway. Several DE miRNA-mRNA matches were suggested to play crucial roles in mediating immune functions against viral evasion. These results revealed the potential regulatory roles of miRNAs in the immune response of the two Ri chicken lines against HPAI H5N1 virus infection in the lungs.

• Animal Bioscience
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• 제37권6호
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• pp.993-1000
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• 2024

Objective: This study was conducted to investigate the differential expression of the major histocompatibility complex (MHC) gene region in Eimeria-infected broiler. Methods: We profiled gene expression of Eimeria-infected and uninfected ceca of broilers sampled at 4, 7, and 21 days post-infection (dpi) using RNA sequencing. Differentially expressed genes (DEGs) between two sample groups were identified at each time point. DEGs located on chicken chromosome 16 were used for further analysis. Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis was conducted for the functional annotation of DEGs. Results: Fourteen significant (false discovery rate <0.1) DEGs were identified at 4 and 7 dpi and categorized into three groups: MHC-Y class I genes, MHC-B region genes, and non-MHC genes. In Eimeria-infected broilers, MHC-Y class I genes were upregulated at 4 dpi but downregulated at 7 dpi. This result implies that MHC-Y class I genes initially activated an immune response, which was then suppressed by Eimeria. Of the MHC-B region genes, the DMB1 gene was upregulated, and TAP-related genes significantly implemented antigen processing for MHC class I at 4 dpi, which was supported by KEGG pathway analysis. Conclusion: This study is the first to investigate MHC gene responses to coccidia infection in chickens using RNA sequencing. MHC-B and MHC-Y genes showed their immune responses in reaction to Eimeria infection. These findings are valuable for understanding chicken MHC gene function.