Fowl Cholera (Pasteurella multocida): Acute Septicemia & Lesions
Scientific manual covering Pasteurella multocida capsule serotypes, acute vascular collapse, dark swollen wattles, and bacterin prophylaxis.
Scientific Overview
Fowl Cholera is a contagious bacterial disease of poultry caused by Pasteurella multocida. It manifests in acute form as fatal septicemia with sudden high mortality, or in chronic form as localized fibrinous infections of wattles, hock joints, and cranial air spaces.
Etiology & Capsule Serotypes (A, D, F)
Fowl Cholera is defined as a bacterial infection caused by Pasteurella multocida, a Gram-negative facultatively anaerobic bipolar-staining coccobacillus. Capsule types A and F are most prevalent in poultry outbreaks.
Reservoirs include wild waterfowl, rodents, cats, and asymptomatic carrier birds. Transmission occurs via oral ingestions or aerosol droplets.
Acute vs Chronic Pathological Lesions
Necropsy findings vary dramatically by disease phase:
- Acute Septicemic Form: Birds found dead without prior symptoms. Widespread petechial hemorrhages on epicardial fat, proventriculus, and serosal membranes. Liver is enlarged with pinpoint greyish-white necrotic foci.
- Chronic Localized Form: Dark, swollen, hot wattles containing cheesy caseous exudate; purulent arthritis of hock joints and middle ear infections causing torticollis.
Treatment & Bacterin Immunization
Antibiotics (Penicillin, Tetracycline, Sulfamethazine) lower mortality during acute outbreaks. Preventive control relies on rodent control and inactivated oil-emulsion P. multocida bacterins administered at 8 and 12 weeks of age.