Møller, B. Horne2; Bisgaard, Magne4; Pors, Susanne Elisabeth4
1 Veterinary Clinical Microbiology, Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, Københavns Universitet2 Department of Veterinary Disease Biology, University of Copenhagen3 Section of Microbiology, Department of Veterinary Disease Biology, Faculty of Life Sciences, Københavns Universitet4 Section of Microbiology, Department of Veterinary Disease Biology, Faculty of Life Sciences, Københavns Universitet
The aim of this study was to investigate the pathogenic potential of Avibacterium endocarditidis. Forty broiler breeders were inoculated with one of three doses of the organism and killed at different time points. Bacteriology, pathology and fluorescence in-situ hybridization (FISH) were performed to evaluate bacterial growth and the development of lesions. Abundant growth in pure culture of A. endocarditidis was always obtained from valvular lesions, while only poor growth or no growth was obtained from liver and spleen lesions, confirming previous observations from naturally occurring cases. Gross lesions and histopathological findings confirmed previous observations. Valvular lesions were acute, ranging from slight thickening of the valves to severe inflammation. In most cases, bacteria colonized the valves. Lesions observed in the spleen included different degrees of necrosis and liver lesions ranged from very small infarcts to large areas of coagulative necrosis. Arthritis occurred in 19 birds, 15 of which tested positive for A. endocarditidis. Most birds developed bacteraemia, but the inability to isolate bacteria from the liver and spleen and the lack of bacteria demonstrated by FISH and histopathology, suggested lack of fulminant septicaemia. A significant correlation between the size of dose inoculated and development of valvular endocarditis was not observed; however, regressive changes in the ovary, liver necrosis and hepato-, spleno- and renomegaly were significantly dose dependent. A. endocarditidis represents a potential pathogen for chickens, the reservoir of which remains to be determined.
Journal of Comparative Pathology, 2014, Vol 150, Issue 2-3, p. 266-275
The Faculty of Health and Medical Sciences; Avibacterium endocarditidis; poultry; valvular endocarditis