Perosis Disease in Chickens

Cause: Perosis is a nutritional deficiency of choline, manganese, and/or B vitamins (such as niacin, biotin, and folic acid).

Thankfully, nutritional deficiencies can be avoided by making sure your flock has free-choice access to complete, nutritionally-balanced feed. Chicken scratch or kitchen scraps alone are not considered a balanced diet.

Perosis disease, also known as slipped tendon or chondrodystrophy, is a condition that affects the skeletal development of chickens, specifically their legs. It is a metabolic disorder caused by a deficiency in manganese, which is an essential trace mineral required for normal bone and cartilage development.
In chickens, Perosis disease typically affects young, rapidly growing birds between the ages of 2 to 8 weeks, which are in the critical stage of skeletal development. It is commonly seen in broiler chickens, which are raised for meat production, but can also occur in other types of chickens such as layers or breeders.
The main symptom of Perosis disease is the deformation and weakening of the leg joints, especially the hock joint (the equivalent of the ankle joint in humans). The tendons that hold the joint in place become stretched or slip out of their normal position, causing the affected bird to have difficulty standing or walking. The legs may appear twisted or bent, and the affected chickens often have an abnormal gait or may be unable to walk at all.
Perosis disease is believed to be caused by a combination of genetic and environmental factors. Diets deficient in manganese, or imbalanced ratios of other nutrients such as calcium, phosphorus, and vitamin D, can contribute to the development of Perosis disease.
Prevention and treatment of Perosis disease involve addressing the underlying nutritional deficiencies. This may include providing a balanced diet that meets the specific nutrient requirements of chickens, including adequate levels of manganese, calcium, phosphorus, and vitamin D. Nutritional supplements or additives may be added to the feed to correct any deficiencies.
If Perosis disease is diagnosed in a chicken, early intervention is crucial. Treatment may involve providing supportive care, such as splinting or bracing the affected legs, to help the bird maintain mobility. In severe cases, affected chickens may need to be euthanized to prevent unnecessary suffering.
Good nutrition, proper management practices, and early intervention can help reduce the incidence and severity of Perosis disease in poultry flocks.