Correlation Between Mutations Of Chicken Interferon And Resistance To Marek’s Disease

Marek’s disease of chickens caused by Marek’s disease virus is highly contagiouslymphoproliferative. It’s tied with Newcastle disease and infectious bursal disease for thethree major diseases which harm the healthy development of the poultry industry. It can causeflocks with higher morbidity and mortality. The spread of the virus through the air, and it hasa strong infectivity. The prevention of MDV is very difficult. It is one important way tocontrol Marek’s disease that looking for high resistance genes, improving the gene frequencywhich is resistance to diseases and enhancing disease resistance of chickens from the genetics.Interferon (IFN) is the most important member of the multifunctional cytokine family inthe candidate gene which affects poultry disease resistance. Not only does it have antiviralanticity, but also has a variety of biological functions such as immune regulation. In IFNfamily, IFN-gamma plays a major role in immune regulation and a two-way adjustment in thebody. It can promote the expression of MHCII; ChIFN-γ can stimulate NK cells and enhancethe killing and help the body get rid of the virus infection. And it also can contribute directlyto the T and B cell differentiation and CTL mature stimulate B cells to secrete antibodies, soas to enhance immune function.In this study, we conducted the comparative test of hatchability and artificial challengewith three fine local chickens (Shouguang chicken/Jiningbairi chicken/Wenshangluhuachicken) from Shandong Province and SPF chicken. Detected the SNPs of IFN-γ withPCR-SSCP to analysis of the relationship between the IFN-γ gene mutation and chickensagainst Marek’s disease. Sampling randomly and testing blood indicators for each group ofchickens after challenge,4-week-old,6-week-old and8weeks of age. The chickens were nosignificant difference in the total number of white blood cells (p>0.05). There was a mutationof C�'T in IFN-γ354bp. Result: we compared the genotype frequencies between four flocks.The mutant gene frequency in the two flocks of Jiningbairi chicken and Wenshangluhuachicken were higher than Shouguang chicken and SPF white leghorn chicken. Statistics the mortality of the four infected flocks at60-day-old. Result was that: The mortality of SGchicken was65.4%; SPF white leghorn chicken was60.5%; JB chicken was25.4%and WLchicken was23%. SPF white leghorn chicken and Shouguang chicken were highestsusceptibility. The difference between the two was not significant. Bairi chicken and Luhuachicken were strongest resistance. The difference between the two was not significant. Butthere was significant difference between the strongest resistance chickens and the highestsusceptibility chickens. IFN-γ mutation gene frequency and mortality at60-day-old was somecorrelation(r=－0.978, p<0.05). Conclusion: The early resistance to Marek’s diaease of Bairiand Luhua chickens was higher than Shouguang chicken in the three local varieties of chicken;Marek’s virus did not affect the total number of white blood cells in the body of threechickens; there was correlation between the ability of early resistance to Marek’s and thefrequency of the mutant gene; TT genotypes resistant to Marek’s disease.