Poultry can be affected by various diseases, including viral, bacterial, fungal, parasitic, and metabolic disorders. Below is a classification of common chicken diseases and their key characteristics.
◎ Pathogen: Influenza A virus (highly pathogenic strains are deadly). ◎ Symptoms: Swollen face, purple combs/wattles, sudden death, drop in egg production. ◎ Control: Culling infected flocks, movement restrictions, vaccination (in some countries).
◎ Pathogen: Avian coronavirus. ◎ Symptoms: Sneezing, nasal discharge, drop in egg production (misshapen eggs), kidney damage in some strains. ◎ Control: Vaccination (live and killed vaccines).
◎ Pathogen: Birnavirus. ◎ Symptoms: Diarrhea, trembling, swollen bursa of Fabricius, immunosuppression. ◎ Control: Vaccination (maternal and live vaccines).