| Marek's disease (MD) is a lymphoproliferative disease of chicken and has been causing big losses in the poultry industry. Research on the screening of MD resistance-related genes, with the purpose provide some genetic molecular markers, will enhance the resistance breeding of Three-Yellow chicken, and be a complementary measure to the conventional vaccination strategy for the effective control of MD. An elementary research was done and the results were documented in the following:46 7-Day-old birds of general line, which were divided into 2 groups: Group A, 24 unvaccinated birds and Group B, 22 birds vaccinated with HVT on one-day-old and 53 7-Day-old birds of MD-resistant line, which were divided into anther 2 groups: Group C, 27 unvaccinated birds and Group D, 26 birds vaccinated with HVT on one-day-old, of Xiayan chicken were challenged with a virulent Guangxi isolate YL040920/C6 of serotype 1 Marek's disease virus (MDV-1). Each group of birds was raised separately in routine and the death of birds was recorded daily until the whole trial was finished at 12 weeks post-challenge (PC). The results showed that the death and the tumor occurrence of MD for Group A, B, C, and D were 66.67% and 75.00%, 63.63% and 72.72%, 44.44% and 48.14%, 42.31% and 46.15% respectively. The death and the tumor occurrence of MD of resistance line were significant less than those of general line by the t-test analysis (P<0.05 and P<0.01), respectively, but there were not significant different between the vaccinated and unvaccinated birds (P> 0.05). With the statistics of tumor occurrence in different viscera organs, heart tumor was the most common tumors (43.5%), and then was liver (29%) and skin (10.6%). Sera were collected from the challenged birds after the vaccinations of commercial vaccines of Newcastle disease (ND) and Avian Influenza (AI) for the detection of antibody responses by using hemagglutination inhibition (HI) test, and lower HI titers than normal were observed and that provided an... |
PDF Full Text Request