Identity

A critical-priority enteric protozoan disease caused by host-specific Eimeria species. These obligate intracellular parasites replicate asexually and sexually within the intestinal epithelium, rupturing host cells, destroying villous architecture, and causing severe hemorrhage and poor FCR.

Overview

Coccidiosis is a paramount commercial pathogen for the broiler industry. It exhibits strict anatomical localization (e.g., E. tenella in the ceca, E. acervulina in the duodenum). The severe destruction of the mucosal epithelium releases plasma proteins that act as a direct predisposing trigger for Clostridium perfringens (Necrotic Enteritis). Management requires strict litter moisture control (<25%) through daily tilling and the use of chemical or ionophore coccidiostats. In India, live coccidiosis vaccines containing attenuated oocysts are administered early to commercial layers and breeders.

Structured Facts

Classification

Parasitic > Infectious Pathogen

Epidemiology

• Prevalence in India: Highly prevalent
• Severity: Critical
• Affected Species: Poultry
• Affected Age: Young growing chickens between 2 and 6 weeks of age
• Transmission: Extremely high horizontal transmission via fecal-oral ingestion of sporulated oocysts
• Seasonality: Promoted by damp litter conditions
• Mortality: 1% to 5% (E. acervulina); up to 50% (highly pathogenic E. tenella / E. necatrix)
• Morbidity: Approaches 100% in high-density houses
• Economic Importance: Critical (direct mortality, clinical morbidity, high FCR)

Clinical Signs

• Early/Intermediate: Severe depression, huddling, anorexia, ruffled feathers, pale combs/wattles, weight loss
• Advanced: Mucoid or frankly bloody droppings, poor FCR. Targets Intestinal Tract (Duodenum, Jejunum, Ileum, Ceca).
• Postmortem Findings: E. tenella: severely distended cecal pouches filled with clotted blood. E. necatrix: petechial hemorrhages/white foci on mid-gut serosa ("salt-and-pepper"). E. maxima: thickened mid-gut with orange mucus. E. acervulina: white ladder-like plaques in duodenum.

Diagnosis

• Field Diagnosis: Bloody droppings, pathognomonic species-specific intestinal lesions
• Laboratory Tests: Oocysts in fecal flotations; identifying schizonts/merozoites in mucosal scrapings via light microscopy
• Differential Diagnosis: Necrotic Enteritis, Helminthiasis

Treatment

• Immediate Actions: Tilling of litter
• Medicines: Monensin Sodium, Maduramicin Ammonium, Narasin, Diclazuril, Clopidol, Decoquinate, Salinomycin, Nicarbazin
• Withdrawal: Monensin (3 Days), Maduramicin (5 Days), Narasin (3 Days), Diclazuril (0 Days), Clopidol (5 Days), Decoquinate (3 Days)
• Veterinary Intervention: Statutory veterinary supervision required

Prevention

• Vaccination: Live coccidiosis vaccines (attenuated/non-attenuated oocysts) at 3 to 5 days of age (layers/breeders)
• Biosecurity: Mitigated by standard Biosecurity Protocols
• Farm Management: Litter raking/tilling to maintain moisture < 25%; Chemical/Ionophore coccidiostats in feed

Quantitative Data

• Morbidity Rate: Approaches 100%
• Mortality Rate: 1% to 50% depending on species
• Target Age: 2 to 6 weeks
• Litter Moisture Target: < 25%

Relationships

• Vaccines: Live coccidiosis vaccines
• Medicines: Monensin, Maduramicin, Narasin, Diclazuril, Clopidol, Decoquinate, Salinomycin, Nicarbazin
• Management: Litter Raking / Tilling
• Predisposing Relationships: Direct trigger for Clostridium perfringens (Necrotic Enteritis)