Molecular detection and phylogenetic analysis of Avibacterium paragallinarum in an Infectious Coryza outbreak at a poultry farm in Meghalaya, Northeastern India.

Infectious coryza is a bacterial disease of poultry that results in severe economic losses to the poultry industry. This study investigated an outbreak on an organized farm in Meghalaya, affecting pullets of the BV380 variety specifically bred to lay brown eggs. The pullets exhibited clinical signs of edematous eyes with purulent discharge from the eyes and nostrils, swelling of infraorbital sinuses, and caseous cheesy exudates. Swabs taken from the infra-orbital sinus and caseous exudate underwent PCR-based molecular confirmation to diagnose Avibacterium paragallinarum. Phylogenetic analysis revealed close clustering with Chinese counterparts. The outbreak was controlled by oral medication with sulphamethoxazole and trimethoprim, following which the morbid birds recovered uneventfully.