Micromorphological changes on the embryonic membranes of turkey eggs infected with Aspergillus fumigatus and their importance for embryonic survival

• Main Authors: Jezdimirović Nemanja V., Kureljušić Branislav I., Kureljušić Jasna M., Jakić-Dimić Dobrila P., Ilić Živka Đ., Miljković Biljana, Radanović Oliver Č., Cvetojević Đorđe N., Ivetić Vojin L., Jezdimirović Milanka B.
• Format: Article
• Language: English
• Published: Matica srpska 2013-01-01
• Series: Zbornik Matice Srpske za Prirodne Nauke
• Subjects: Aspergillus fumigatus; embrionirana ćureća jaja; jajčane opne; morfološke promene
• Online Access: http://www.doiserbia.nb.rs/img/doi/0352-4906/2013/0352-49061324263J.pdf

Aspergillosis is a frequent fungal disease of young and adult poultry in our commercial flocks. Infection can occur after hatching by inhalation of Aspergillus conidia which can be present in contaminated hatcheries, or later, by spores from moldy litter, dust, faeces or feed. Spores from the surface of egg shell can penetrate inside of an egg. The main characteristic of aspergillosis is granulomatous inflammation of respiratory system, although generalized form is possible as well. Multiple yellow nodules can be seen as major patomorphological changes and they are usually localized in lungs, air sacs, and can also be found in spleen, brain, subcutis and eyes. Egg embryos are quite susceptible to infection by Aspergillus fumigatus during incubation. In this study, the history of a case on one local farm with mortality rate of 7.2% in the turkey flock is presented. At the same time, 28 day old 30 incubated hatching turkey eggs were sampled, that were unable to hatch. The aim of the present work was to determine the cause and to identify the agent of embryonic mortality. Total of the 30 eggs were opened, and 16 of them had thickened egg membranes in the area of air sac. Membrane thickening was visible and circumscript or diffuse presence of black-grey or grey-green fungal growth was observed. Only 3 samples air sacs were filled with developed stages of fungi. To evaluate histopathological lesions, changed egg membranes were processed by standard histological technique. Dominant microscopic finding was thickening of egg membranes as a consequence of fungal growth and many of them penetrated deep towards embryo. Most of the hyphae were growing vertically through membranes. On the outside surface of the membranes, the elements of fungi (conidial heads with phialids and spores on them), could be clearly observed. These changes were responsible for embryonic death, which on the basis of the size of dead embryos occurred between 7th and 10th day of incubation. Aspergillus fumigatus was isolated and identified from the content of air sacs. [Projekat Ministarstva nauke Republike Srbije, br. III 46009 i br. TR 37015]