PATHOGENESIS OF REDUCED EGG-PRODUCTION AND SOFT-SHELLED EGGS IN LAYING HENS ASSOCIATED WITH LEUCOCYTOZOON CAULLERYI INFECTION

The pathogenesis of reduced egg production with soft-shelled eggs in l aying hens naturally infected with Leucocytozoon caulleryi was investi gated. Many large schizonts of L. caulleryi schizonts were seen in the ovary and oviducts of chickens. Granulomatous and lymphocytic inflamm ation, edema, and pressure atrophy were associated with these schizont s. The uterine region that secretes the egg shell exhibited the most s evere damage. These lesions in the reproductive organs may explain the mechanism for causing the reduced egg production and soft-shelled egg s in laying hens infected with L. caulleryi.