ABSTRACT
Traditional live Infectious Bursal Disease virus [1DDV] vaccines were thought to have some v-4 degree of adverse effect on the bursa of fabricous of chickens, which in turn may interfere with antibody production against other poultry vaccines. In this study, 15 broiler flocks vaccinated -; against avian influenza [AI] virus were sampled for serum. The flocks have received IBDV vaccination either from the conventional live vaccines or with the new recombinant subunit vaccine. Haemagglutination inhibition [HI] test was carried on sera using different AI antigens. Sera measured by the variant A/chicken/EgypWRLCU67/2011 [H5N1] isolate showed significant difference [P<0.05] between mean HI titers of bird vaccinated by traditional IBDV. vaccines and titers of those vaccinated with the subunit vaccine. Results indicate that live IBDV vaccines may affect the efficacy of AI vaccine, and the study encourages the use of the field AI isolates for reliable interpretation of HI test results
ABSTRACT
Two commercial chemical disinfectants which are commonly used currently in the Egyptian markets were tested individually for effectiveness against highly pathogenic avian influenza virus [HPAIV]A/chicken/Egypt/13VIR3729/4/2013 [H5N1]., which currently hit the Egyptian poultry farms at 2013, The tested agents were sodium hypochlorite 5% available chlorine [NaOCL] and PERACLEAN 5%[registered][Peroxyacetic Acid4.9% and hydrogen peroxide 26.5%]. The test was performed in accordance to the guidelines of American environmental protection agency [EPA], using a carrier test with surfaces [coupons] designed specially to mimic the poultry house floor and made from concrete cement, [under dirty condition resembled phase two, step two of European Committee for Standardization [CEN]. At room temperature which mimic the field condition in the Egyptian poultry farms, both sodium hypochlorite with concentration [250ppm], and PERACLEAN 5%[registered]with concentration [1%], were not able to inactivate the virus after 5 minutes contact time, while inactivation was achieved within 30 minutes contact time, which proved one of the golden rules when applying a disinfectant, that was allowing the increase of contact time between the disinfectant and influenza virus
Subject(s)
Animals , Disinfectants , Breeding , /growth & developmentABSTRACT
Necrotic enteritis and the subclinical form of Clostridium perfringens infection in poultry are caused by C. perfringens type A, producing the alpha toxin, and to a lesser extent type C, producing both alpha toxin and beta toxin C and have become serious threats to poultry health. This study was undertaken to determine the activity of 4 commonly available disinfectants against C. perfringens spores after 5,7.5,10,15,30 and 60 minutes of contact under dirty conditions, Of the 4 products tested, calcium hypochlorite 1% and Germicidan KOK 4% achieved the required reduction in microbial viability [>/=10[3]-fold] for relatively long contact times of 30 min, under dirty [3% yeast] conditions, One product [Biosentury 904, 2% conc] achieved the required reduction in microbial viability [>/=10[3]-fold] for contact times of 10 minutes, while Prophyl 75,1% concentration. achieved the required reduction in microbial viability [>/=10[3]-fold] for contact times of 5minutes.Upon addition of formic acid 2% and urea 1% the required reduction improved for [Biosentury 904, 2% conc] and Prophyl 75,1% concentration and achieved after 5 minutes and after 7.5 minutes for Germicidan KOK 4% while calcium hypochlorite was not improved by addition of formic acid 2% or urea 1%. Application of surface test using the four disinfectants was used alone and in combination with formic acid 2% or urea 1% showed nearly the same results obtained in the suspension test
Subject(s)
Animals , Disinfectants , Poultry , SporesABSTRACT
Two HPAI H5N1 viruses were isolated from vaccinated layer and broiler commercial poultry farms in Egypt at years 2011 and 2013; respectively. By phylogenetic analysis, the viruses fall into two genetically diverse clades: [i] A/chicken/Egypt/VRLCU67/2011 classified as a variant virus, clade 2.2.1.1; and [ii] A/chicken/Egypt/13VIR3729-4/2013 classified as a classic virus, clade 2.2.1. Cross HI-test confirmed that the reaction between the two viruses is weak; furthermore, it showed the antigenic diversity between viruses belong to different clades and antigenic groups. Antigenic relatedness was calculated between six AI antigens and their antisera representing the different clades and antigenic groups circulated in Egyptian field; including the A/chicken/Egypt/VRLCU67/2011 strain which showed very low R-values with the other viruses' groups; ranging from 17 % to zero. Results demonstrated the genetic and antigenic diversity of the variant viruses and how can the vaccine seed be a weak point in the vaccination program that could be broken by the drifted viruses antigenically distant from the vaccine strain