Providing nutritional supplements to captive birds is very important, they rarely have access to a truly natural diet and need a 'top up'.
For the retired ex-bats which are lucky enough to be rescued this is incredibly important, these have been birds bred for high production. They operate metabolically at a high level, draining their reserves and they should receive nutritional supplements as routine as they have done in production.
The 'fresh' rescues are often very drained of vitamin D3, through lack of daylight and through controlling the calcium levels through production. Many rescues also rely on our Zolcal D or Nutrobal. The latter is a very effective calcium and D3 source for addition to mashes.