Pathomorphological changes in spontaneous cases of hydrosalpinx in commercial layer chicken

The present study was undertaken to investigate the prevalence and pathology of oviduct in spontaneous cases of hydrosalpinx in commercial layer chicken for a period of three years (2005 to 2008). Hydrosalpinx was observed in birds of 41–80 week age group and was accounted to 18.72 per cent of the birds investigated for oviduct abnormalities. In the affected flocks morbidity, egg production drop and mortality were 1 to 10, 2 to 4 and 0 to 0.5 per cent, respectively. Grossly, infundibular region of the oviduct revealed dilatation with creamy white mucus mixed fluid of about 120 to 750 ml and the remaining parts of the oviduct were patent and either atrophied or apparently normal depending up on the quantity of fluid. Ovarian follicles were either regressed or normal with follicular hierarchy. Histopathologically, reduction in the size of mucosal folds, severe atrophy, degeneration and desquamation of surface epithelium, atrophy of tubular glands and the formation of submucosal germinal centers were noticed in the different regions of oviduct. The HI titre for NDV, IBV and EDS -76 virus was 32 to 128, 32 to 512 and 2 to 8, respectively and in ELISA 100 and 97 per cent of serum samples were positive for MG and MS in the affected flocks. Immunoperoxidase staining of affected oviduct revealed golden brown fine granular material in the surface epithelium of infundibulum, magnum and uterus regions of the oviduct against IBV and mycoplasma. It was concluded that the affected birds might have had individual or combined infection of IB and MG which would have damaged the delicate infundibular fimbriae leading to adhesion and impairment of the normal fluid movement within the blocked oviduct resulting in development of characteristic cyst like lesion. However, further molecular studies are required to confirm the etiological agents in hydrosalpinx cases.