Types of Chicken Diseases

Many different diseases can affect chickens. The diseases can be hard to diagnose because many of them cause the same symptoms. Call your veterinarian immediately if you think your chicken is ill, especially if you own many chickens that live in close proximity. Some diseases are contagious. Chicken diseases are either genetic, dietary, bacterial or viral.

  1. Aspergillosis

    • Aspergillosis is a respiratory illness that affects chickens when they inhale a fungus called aspergillus. Acute aspergillosis can cause difficulty breathing, decrease in appetite or even death. More common than acute aspergillosis is chronic aspergillosis, which is more deadly because symptoms might not be apparent until too late. The disease can progress and infect organs other than the respiratory system. Chickens infected with aspergillosis can recover through surgery to remove lesions or through medications prescribed by a veterinarian.

    Fowl Pox

    • Two forms of fowl pox may infect chickens. The dry form causes raised lesions that look like warts on parts of the chicken that don't have feathers, such as the head and legs. The wet form causes lesions in the mouth and respiratory passages. Fowl pox is contagious between chickens. It has no treatment, but normally goes away in a few weeks.

    Newcastle Disease

    • Newcastle disease is highly contagious among chickens and is a lethal disease that attacks the internal organs. No documented cases of Newcastle disease have occurred in the United States. Symptoms include respiratory distress or paralysis in the legs. No specific treatment exists for Newcastle disease, but antibiotics can be given to prevent further infections. Depending on the strain of the disease, it can be deadly or the chicken can recover.

    Pullorum

    • Pullorum is a disease that mother hens transmit to their chicks, killing the chicks. The mother hen may have diarrhea, weakness, white feces or green bile. Local, state or federal government usually handles pullorum outbreaks. No treatment exists for sick chickens. United States law requires that chickens infected with pullorum be put down so that the rest of the flock isn't infected.

    Egg Drop Syndrome

    • Egg drop syndrome causes reduced eggs in chicken populations all over the world, including within the United States. The only symptom of this disease is a reduction in egg production and the laying of thin-skinned eggs or eggs with no skins. Infected mother hens transmit the disease to their chicks. Inducing the hens to molt seems to bring egg production back to normal.