Effect of some bacterial diseases on egg production in laying chickens

This research was dens to study the effect of some bacterialdiseases on egg production and control of some diseases by vaccination.j, Twenty five laying farms suffering from 3-10% DROP in the eggproduction, increased mortality and pathological lesion in thereproductive organs was examined for bacteriological agent.eleven types of bacteria were isolated, Staph aureus,Streptococcus, A ctinomycis blogens, Enterococci, Eicoll,Klebsiella, Proteus, Pseudomonas, Salmonella and yersinla enterocolttica.2- Salmonella isolates were serotyped as Salmonella enteritidis,Salmonella typhimurium, Salmonella paratyphi A andSalmonella Kentucky. Salmonella paratyphi A was the mostpathogenic strain for young chicks among the isolatedSalmonella strains. E. coli isolates were serotyped as E. coli078,01, 0166, 0146, 018, 086 and 020. E. coli 0166 was themost pathogenic serotype for young chicks among the isolatedstrains.3- ~ffleacy of laboratory prepared bivalent bacterin prepared f)’omisolated Salmonella enteritidis and Salmonella typhimuriumwas studied in 19 weeks old bovans laying hen. Birds werevaccinated twice at 19 and 21 week old and infected with eitherSalmonella enteritidis, Salmonella typhimurium or Salmonellaparatyphi A at 24weeks of age. The killed bacterin protectschickens against salmonella infection, vaccinated group