Studies on bacterial causes of early embryonic death in chicken embryos

The present study aimed to identify different bacterial species causing embryonic death in chicken eggs in Giza and Ismailia Governorates The isolates were identified with the ordinary bacteriological methods as well as with serological methods and PCR A total of 540 samples including sixty non fertile eggs 80 dead in shell embryos at more than 14 days of ages 100 contained dead embryos at different stages of development 7 and 14 days And sixty environmental swab samples were collected from different parts of incubators hatcheries refrigerators receiving room and hands of workers These randomly collected samples were subjected to aerobic bacteriological examination in a trial to detect the actual bacterial causes of this problem Forty percentages of the examined egg samples and 53.33% of the swab samples were positive bacterial isolation The results of bacterial isolation revealed that Proteus species were the most prevalent organisms isolated from dead in shell embryos and eggs contain dead embryos with an incidence of 15.63 % and 11.5 % respectively and from infertile eggs with an incidence of 6.67 % Also the rate of isolation the collected swabs reached to 6.67 % The Bacillus species were isolated from dead in shell embryos with an incidence of 11.25 % The most prevalent organism isolated from infertile eggs was E coli with an incidence of 7.5 % The incidence of isolation of E coli from environmental swabs of different parts of egg hatcheries was 10 % The recovered E coli isolates were serogrouped into O55 O78 O86 O119 O125 and O128 from the examined environmental swab samples O78 was isolated at high incidence rate 5% followed by O55 3.33% Staphylococcus aureus was isolated from the infertile eggs with an incidence of 5.83 % Pseudomonas aeruginosa was the most prevalent organism isolated from environmental swabs with an incidence of 13.3 % Its rates of isolation from infertile eggs eggs contained dead embryos and dead in shell embryos reached to 4.17% 2 % and 1.88 % respectively Salmonella species was recovered from environmental swabs of different parts of egg incubators with an incidence of 6.67% and from infertile eggs eggs contained dead embryos and dead in shell embryos with an incidence of 3.33 % 3 % and 3.13 % respectively The isolated Salmonella species were serogrouped into Salmonella enteritidis Salmonella Pullorum Salmonella Typhimurium and Salmonella Gallinarum Klebsiella species isolated from both infertile eggs and eggs contained dead embryos in a percentage of 1.67% and 1.5% respectively The lowest incidence of the isolated bacterial species from both infertile eggs and dead in shell embryos was Streptococcus species with an incidence of 0.83 % and 0.63 % respectively Using Polymerase chain reaction PCR the confirmation of the isolation of the abovementioned bacterial species was confirmed