美國食品藥品監督局(FDA)正在修改25-羥基維生素D3作為動物飼料和飲水添加劑方面的法規，允許25-羥基維生素D3在蛋雞，種雞和火雞中作為活性維生素D3來源。這是應DSM提出的申請而做出的修訂。

25-羥基維生素D3在飼料和飲水中使用需遵循以下：

(1)在蛋雞、種雞飼料中使用不能超過69ppb，飲水中不能超過34.5ppb。

(2)在火雞飼料中使用不能超過92ppb，在飲水中使用，對于0~3周齡火雞不能超過25ppb，4~11周齡火雞不能超過36ppb，11周齡以上火雞不能超過45ppb。

主要內容如下：

The Food and Drug Administration (FDA, we, or the Agency) is amending the regulations for food additives permitted in feed and drinking water of animals to provide for the safe use of 25-hydroxyvitamin D3 as a source of vitamin D3 activity for layer and breeder chickens and turkeys. This action is in response to two food additive petitions filed by DSM Nutritional Products.

The food additive, 25-hydroxyvitamin D3, may be safely used in accordance with the following prescribed conditions:

(a) The additive is used or intended for use as a source of vitamin D3 activity in animal feed or drinking water in accordance with good manufacturing and feeding practices as follows:

(1) In feed or drinking water of layer and breeder chickens not to exceed 69 parts per billion (ppb) in feed or 34.5 ppb in drinking water.

(2) In feed or drinking water of turkeys not to exceed:

(i) 92 ppb in feed; or

(ii) In drinking water, 25 ppb for turkeys up to 3 weeks of age, 36 ppb for turkeys from 4 to 11 weeks of age, or 45 ppb for turkeys over 11 weeks of age.

(b) The additive consists of not less than 94 percent 25-hydroxyvitamin D3 (9,10-secocholesta-5,7,10(19)-triene-3b, 25-diol).

(c) The additive meets the following specifications:

(1) Not more than 1 percent of any individual sterol.

(2) Not more than 5 percent water.

(3) Not more than 20 parts per million (ppm) lead.

(4) Not more than 20 ppm aluminum.

(5) Not more than 1.0 percent solvents and non-detectable levels of 2′, 4′, 5′, 7′ tetraiodofluorescin.

(6) Not more than 1 ppb 1, 25-dihydroxycholecalciferol.

(d) To assure safe use of the additive, in addition to the other information required by the Federal Food, Drug, and Cosmetic Act, the label and labeling shall contain:

(1) The name of the additive.

(2) A statement to indicate the maximum use level of 25-hydroxyvitamin D3 must not exceed 69 ppb in feed or 34.5 ppb in drinking water for layer and breeder chickens.

(3) A statement to indicate for turkeys the maximum use level of 25-hydroxyvitamin D3 must not exceed 92 ppb in feed; or in drinking water, 25 ppb for turkeys up to 3 weeks of age, 36 ppb for turkeys from 4 to 11 weeks of age, or 45 ppb for turkeys over 11 weeks of age.

(4) Adequate use directions to ensure that 25-hydroxyvitamin D3 (and all premixes) is uniformly blended throughout the feed or drinking water.

(5) An expiration date on all premix labeling.

(6) A statement on all premix labeling (feed and drinking water forms) that 25-hydroxyvitamin D3 cannot be used simultaneously in both feed and water.