Causes of Rickets

Rickets in humans’ chickens and every other animal that gets rickets is caused by a deficiency of Vitamin D3, phosphorus, or imbalance between Calcium and Phosphorus. Of all these, a deficiency of Vitamin D3 is the most common, and that is often secondary to bad feed that has been depleted of fat-soluble vitamins including Vitamin D. Ultimately, rickets usually occurs due to improper nutrition which results in poor skeletal calcification.

Signs and Symptoms

In chickens, rickets typically causes soft and pliable or rubbery bones and beaks that appear deformed. You can see this and other clinical signs such as lameness as early as 14 days of age. This typically happens in growing chickens (aka younger birds).

In contrast reduced dietary Calcium in laying hens results in reduced shell quality and subsequently osteoporosis as the hens draw Calcium from bones in order to support shell formation. Osteoporosis in laying hens can cause fractures in areas such as the costochondral junctions of the ribs, the keel, and the thoracic vertebrae. Vertebral fracture may damage the spinal cord and cause paralysis.


Treatment should include proper nutrition and possibly supplementation with Vitamin D3 and/or Calcium Carbonate. When in doubt, call your vet!

In summary proper nutrition is one of the most important things you can provide to your flock. Rickets is a problem mainly in growing birds, but you can prevent rickets by making sure your growing birds get the majority of their diet from a well-balanced commercial poultry feed. To that point, don’t get fancy with your poultry diet as not only deficiencies of calcium, phosphorus, or vitamin D3, but also excess calcium (which induces a phosphorus deficiency) can cause rickets.