Efficacy of fowl pox vaccines against Egyptian isolated strain during 2012

Abstract

Aim: This study was designed to evaluate the protection induced by different commercial fowl pox (FP) vaccines against local FP virus isolated from Giza governorate in Egypt during 2012. Materials and Methods: Efficacy of FP vaccines against local field isolates was determined in seven groups of (20 birds/ group) 6 weeks old specific-pathogen free chicks. Each group was vaccinated via wing web with one of different FP living vaccines and (20) chicks in group (8) did not receive any FP vaccine and served as controls. At the 3rd, 5th, 7th and 10th-day post-vaccination (DPV), all birds were examined for the presence of takes at the site of vaccination. Three weeks post vaccination, serum samples were collected, and the levels of induced antibodies were detected by passive hemagglutination (PH) test. All birds in Groups (1-8A) were challenged individually via the wing web with EID50 103.0 of the Egyptian isolated strain during 2012. Results: Takes detected at the site of vaccination at the 3rd day were ranging from 45 to 70%. This percent increased to 80-95% at the 5th DPV with a maximum elevation of takes at the 7th DPV (90-100%). Geometric mean titer of PH assay antibody titer, 3 weeks post vaccination, was ranging between 5.60 and 9.60 according to the type of vaccine used and with protection 90-100%. Conclusion: Efficacy of some commercial FP vaccines used in the poultry field against the Egyptian isolated strain during 2012 ranged between 90% and 100% according to the type of used vaccine.