Status of Salmonella gallinarum-pullorum infections in poultry in Zambia.

Ten outbreaks of Salmonella gallinarum-pullorum infections on poultry farms in Zambia were investigated. Three cases were seen in day-old broiler chickens and were diagnosed by culture as S. gallinarum-pullorum and characterized as pullorum disease because the mortality was only in the first few weeks. Another case was diagnosed by culture from broiler parent stock. Day-old chicks from two of the three cases were supplied by a hatchery. Five cases in 5-to-18-month-old layer chickens were diagnosed by culture as S. gallinarum-pullorum and characterized as fowl typhoid because of the clinical disease appearing after 5 months of age and the typical lesions of fowl typhoid. The last case was in 5-month-old village-bred fowls and was diagnosed by culture and clinical manifestation as fowl typhoid. Outbreaks of S. gallinarum-pullorum are still manifest in Zambia. Clinically, both pullorum disease and fowl typhoid were observed, and it was indicated that hatchery infection plays an important role in the transmission of S. gallinarum-pullorum.