• Korean Journal of Poultry Science
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• v.42 no.1
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• pp.27-32
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• 2015

In this study, we used two breeds of chicken to identify genomic regions corresponding to necrotic enteritis (NE) resistance. We scanned the genomes of a resistant and susceptible line of Fayoumi and White Leghorn chickens (20 birds/line) using a chicken 60 K Illumina SNP panel. A total of 235 loci with divergently fixed alleles were identified across the genome in both breeds; particularly, several clusters of multiple loci with fixed alleles were found in five narrow regions. Moreover, consensus 15-SNP haplotypes that were shared by the resistant lines of both breeds were identified on chromosomes 3, 7 and 9. Genes responsible for NE resistance were identified in chicken lines selected for resistance and susceptibility. Annotation of the regions spanning clustered divergently fixed regions revealed a set of interesting candidate genes such as phosphoinositide-3-kinase, regulatory subunit 5, p101 (PIK3R5) and inositol 1,4,5-trisphosphate receptor 1 (ITPR1), which participate in immune response. Consensus haplotypes were found in regions containing possibly relevant genes, such as myostatin and myosin, which play important roles in muscle development. Thus, genome scans of divergent selection in multiple chicken lines and breeds can be used to identify genomic regions associated with NE resistance.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.7
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• pp.1037-1047
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• 2017

Objective: Despite an increasing number of investigations into the pathophysiology of necrotic enteritis (NE) disease, etiology of NE-associated diseases, and gene expression profiling of NE-affected tissues, the microRNA (miRNA) profiles of NE-affected poultry have been poorly studied. The aim of this study was to induce NE disease in the genetically disparate Fayoumi chicken lines, and to perform non-coding RNA sequencing in the intestinal mucosal layer. Methods: NE disease was induced in the Fayoumi chicken lines (M5.1 and M15.2), and non-coding RNA sequencing was performed in the intestinal mucosal layer of both NE-affected and uninfected chickens to examine the differential expression of miRNAs. Next, quantitative real-time polymerase chain reaction (real-time qPCR) was performed to further examine four miRNAs that showed the highest fold differences. Finally, bioinformatics analyses were performed to examine the four miRNAs target genes involvement in the signaling pathways, and to examine their interaction. Results: According to non-coding RNA sequencing, total 50 upregulated miRNAs and 26 downregulated miRNAs were detected in the NE-induced M5.1 chickens. While 32 upregulated miRNAs and 11 downregulated miRNAs were detected in the NE-induced M15.2 chickens. Results of real-time qPCR analysis on the four miRNAs (gga-miR-9-5p, gga-miR-20b-5p, ggamiR-196-5p, and gga-let-7d) were mostly correlated with the results of RNAseq. Overall, ggamiR-20b-5p was significantly downregulated in the NE-induced M5.1 chickens and this was associated with the upregulation of its top-ranking target gene, mitogen-activated protein kinase, kinase 2. Further bioinformatics analyses revealed that 45 of the gene targets of gga-miR-20b-5p were involved in signal transduction and immune system-related pathways, and 35 of these targets were predicted to interact with each other. Conclusion: Our study is a novel report of miRNA expression in Fayoumi chickens, and could be very useful in understanding the role of differentially expressed miRNAs in a NE disease model.

• Korean Journal of Poultry Science
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• v.35 no.4
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• pp.335-339
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• 2009

The very low density apolipoprotein-II (apoVLDL-II) gene is closely related with the constitution of the lipoprotein in various tissues. The apoVLDL-II gene have main functions for reducing fat elements from tissues and muscles. Previous results indicated that the polymorphisms in apoVLDL-II gene were positively related with growth and body composition traits in chicken. In this study, we analyzed previously identified apoVLDL-II gene polymorphisms using the PCR-RFLP method and investigated allele and genotype frequencies in three chicken breeds. Data indicated that Korean native chicken and Korean Oge chicken have similar B and F gene frequencies, indicating that this marker can be used for the improvement of growth and body composition traits in those breeds and can be used as marker assisted selection with further verifications.

• Korean Journal of Veterinary Service
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• v.30 no.4
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• pp.497-503
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• 2007

The humoral immune response of chicken vaccinated with fowl and pigeon pox virus vaccines was determined with the protective potentiality of the two vaccines in field condition of Bangladesh. Different aged Fayoumi chicks were subjected for the study. To assess the relationship with better immune response among experimental groups, the average percentage of 'take reaction' was examined and recorded to 97.77% in group A, 93.33% in group B and 100.0% in group C. The level of immune status induced by different vaccinated group was measured by passive hemagglutination (PHA) microplate test method. The mean PHA titer levels after primary vaccination were $33.06{\pm}14.13$ in group A, $32.0{\pm}14.81$ in group B, and $33.0{\pm}13.66$ in group C. Following booster vaccination, the mean PHA titer levels in prior of challenge were increased to $55.46{\pm}14.64$ in groups A and C, and $46.93{\pm}16.52$ in group B. The recorded PHA titer levels of each group at two weeks after challenge were significantly increased to $106.66{\pm}31.22$, $93.86{\pm}33.04$ and $110.93{\pm}29.29$, respectively. The PHA titer levels after vaccination and challenge were significantly increased compared to pre-vaccination titer levels (P<0.01). Although the PHA titer levels among three groups administrated different vaccine combinations in prior of challenge were significantly varied (P<0.01), it was observed that all of the vaccinated chicks were highly protected against challenge infection.