Signs & Symptoms of Coccidiosis in Chickens

Coccidiosis is a chicken disease caused by a microscopic protozoa with signs and symptoms that can be confused with other diseases. The name of these particular protozoa is coccidia and they can infect fowl, domestic animals and humans. Coccidiosis is the most costly disease in the poultry industry. Chickens can become infected with nine different species of coccidia, although two are the most common. They can develop resistance to one species but still remain susceptible to the other eight.

  1. General Symptoms

    • Coccidiosis symptoms include droopiness, listlessness, loss of appetite, fading of yellow color on the legs, pale combs and wattles and ruffled, unthrifty feathers. Infected birds huddle, act chilled and have blood or mucus in their feces. They have diarrhea, become dehydrated and may die. Other symptoms include poor feed digestion, weight gain and feed efficiency.

    Necropsies

    • Since coccidiosis symptoms can be confused with those of other diseases, conduct a necropsy for a more accurate diagnosis. Put on gloves and open up the chicken. Look at the intestines and then cut them open. If the necropsy is done soon after death, it may be possible to identify characteristic lesions or sores in the gut. Coccidiosis causes thickening of the intestine walls, making them feel like sausages. There may be yellow spots, hemorrhages and streaks on the outside and inside of the gut. Scrapings of the gut lining can be sent to your state diagnostic laboratory for diagnosis confirmation.

    Cecal Coccidiosis

    • Cecal coccidiosis may produce bloody droppings and anemia that is often followed by death. Definite diagnosis is possible only from microscopic examination of scrapings from the digestive tract and identification of the coccidia species. Necropsy may show a ballooning of the cecal pouches resulting from being full of blood. Cecal pouches are part of a bird's digestive system. In advanced stages of cecal coccidiosis, the cecae are filled with a cheesy material tinged with variable amounts of blood.

    Intestinal Coccidiosis

    • Intestinal coccidiosis, also prevalent in chickens, is often not as acute and is more chronic than the cecal type. This species of coccidia is less likely to kill, although it causes lesions in the intestines. The lesions vary from a mild inflammation to severe decay or heavy bleeding. Death usually results from the more serious intestine effects.