Systematic Veterinary Virology

Symptoms - Chicken (Layers)

SYMPTOMS - CHICKENS (LAYERS)

• Marked depression with ruffled feathers, inappetence, excessive thirst, cessation of egg production, and watery diarrhea.
• Mature chickens show swollen combs, wattle, and edema surrounding the eyes. The combs are cyanotic at the tips and may have plasma or blood vesicles on the surface with dark areas of ecchymotic hemorrhage and necrotic foci.
• The last eggs laid, after the onset of illness may not have shells.
• The diarrhea begins as watery bright green and progresses to almost totally white.
• Edema of the head, if present, is often accompanied by edema of the neck.
• The conjunctivae are congested and swollen with occasional hemorrhage.
• The legs, between the hocks and feet, may have areas of diffuse hemorrhage.
• Respiratory signs can be a significant feature of the disease, depending on the extent of tracheal involvement and mucus accumulation.
• Death may occur within 24 hours of first signs of disease, frequently within 48 hours, or be delayed for as long as a week. Some severely affected hens may occasionally recover.