INTESTINAL COCCIDIOSIS IN 32-WEEK-OLD ISA BROWN LAYERS – A CASE REPORT

Abstract

A clinical outbreak of coccidiosis was investigated in a flock of 32-week-old Isa Brown layers on a commercial poultry farm in Jos, Plateau State, Nigeria. The birds exhibited a sudden increase in mortality, bloody droppings, lethargy, ruffled feathers, reduced feed consumption, and a significant decline in egg production, falling from an average of 12–13 crates per day to as low as three crates. Five carcasses were submitted for post-mortem examination. Gross pathological findings included pallor of the combs, wattles, shanks, and musculature; ballooning of the intestines with haemorrhagic and necrotic mucosa; and severe haemorrhages in the caecal tonsils. Differential diagnoses considered were coccidiosis, mycoplasmosis, and aflatoxicosis. Based on the clinical history, gross lesions, and therapeutic response, a presumptive diagnosis of clinical coccidiosis was made. A sulphonamide-based anticoccidial agent was administered orally for five days, followed by supportive therapy containing vitamins and electrolytes. Following initiation of treatment, mortality declined sharply from over 80 deaths on day 0 to none by day 4. Egg production also improved progressively, with partial recovery observed by day 7. Histopathological evaluation of intestinal tissues confirmed the presence of schizonts, degenerated crypts, and mucosal destruction which are characteristic of Eimeria spp. infection. This case highlights the critical importance of timely diagnosis, targeted chemotherapeutic intervention, and appropriate supportive care in mitigating production losses during severe coccidiosis outbreaks in layer flocks. It also reinforces the need for improved farm-level biosecurity, routine monitoring, and strategic anticoccidial use as part of sustainable poultry health management