Deformed toes, feet and wings especially in young birds.
This is a deficiency in Vitamin D and should not occur in well-fed birds that have some natural sunlight. If rickets occur, review your feeding regime and add Vitamin D, which can be obtained from your pet & produce store.
The function of Vitamin D is to metabolise minerals, calcium and phosphates. Young chicks are hatched with enough Vitamin D in their system to last around 12 days. The simplest way of supplying birds with Vitamin D is to add a little Cod liver Oil to the seed and mix well. In cases where it is not possible to have natural light you can supply the birds with ultraviolet light so they can make their own Vitamin D, or you can give this vitamin in their food.
As mentioned above, Cod Liver Oil is a good source of vitamin D and is still the favourite source with many bird keepers.
CALCIVET (Vetafarm) Liquid Calcium and Vitamin D3 supplement for birds. It is a palatable syrup that can be diluted in drinking water or administered directly to the bird. When used as directed, Calcivet will not only supply Calcium but will supplement the birds Vitamin D levels and will boost magnesium intake. These three elements are necessary for the production of eggshells and strong bones. Calcivet can be used in egg bound birds to aid in the expulsion of the egg. Calcivet should be administered to breeding birds for approximately one month prior to egg laying and through the chick rearing period. Calcivet can be used with Aviclens, Soluvet, Coccivet but not Psittavet.