[Code of Federal Regulations]
[Title 21, Volume 6]
[Revised as of January 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 21CFR573.640]

[Page 506-508]
 
                        TITLE 21--FOOD AND DRUGS
 
CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN 
                          SERVICES (CONTINUED)
 
PART 573--FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS--Table of Contents
 
                    Subpart B--Food Additive Listing
 
Sec.  573.640  Methyl esters of higher fatty acids.

    The food additive methyl esters of higher fatty acids may be safely 
used in animal feeds in accordance with the following prescribed 
conditions:
    (a) The food additive is manufactured by reaction of methyl alcohol 
with feed-grade fats or oils and consists of

[[Page 507]]

not less than 70 percent methyl esters of the following straight-chain 
monocarboxylic acids: Docosahexanoic acid, eicosapentanoic acid, 
linoleic acid, myristic acid, oleic acid, palmitic acid, palmitoleic 
acid, and stearic acid, and lesser amounts of the associated acid 
esters.
    (b) The food additive meets the following specifications:
    (1) Free methyl alcohol not to exceed 150 parts per million.
    (2) Unsaponifiable matter not to exceed 2 percent.
    (3) It is free of chick-edema factor or other factors toxic to 
chicks, as evidenced during the bioassay method for determining the 
chick-edema factor as prescribed in paragraph (b)(4)(ii) of this 
section.
    (4) For the purposes of this section:
    (i) Unsaponifiable matter shall be determined by the method 
described in Section 28.081, ``Unsaponifiable Residue (20)--Official 
Final Action'' of the ``Official Methods of Analysis of the Association 
of Official Analytical Chemists,'' 13th Ed., 1980, p. 451, which is 
incorporated by reference. Copies are available from the Association of 
Official Analytical Chemists, 2200 Wilson Blvd., Suite 400, Arlington, 
VA 22201-3301, or available for inspection at the Office of the Federal 
Register, 800 North Capitol Street, NW., suite 700, Washington, DC 
20001.
    (ii) The chick-edema factor bioassay method described under ``26. 
Oils, Fats, and Waxes'' in the Journal of the Association of Official 
Agricultural Chemists, Vol. 44, Page 146 (1961), or the method described 
under ``Chick-Edema Factor--Bioassay Method (34)--Official Final 
Action'' in Sec. Sec.  28.113-28.117, ``Official Methods of Analysis of 
the Association of Official Analytical Chemists,'' 12th Ed., 1975, pp. 
509-511, which is incorporated by reference, shall be employed. (Copies 
of the methods are available from the Association of Official Analytical 
Chemists, 2200 Wilson Blvd., Suite 400, Arlington, VA 22201-3301, or 
available for inspection at the Office of the Federal Register, 800 
North Capitol Street, NW., suite 700, Washington, DC 20001.) The 
presence of chick-edema factor shall be determined by a comparison 
between the mean log of the pericardial fluid volumes of a test group 
and of a concurrent negative control group. The significance of the 
difference in pericardial fluid volumes between the test group and the 
negative control group is determined by calculating a ``t'' value 
according to the formula:
[GRAPHIC] [TIFF OMITTED] TR01JA93.412

where:
xt and xc are the means of the logs of the 
pericardial fluid volumes of the test and control groups, respectively;
nt and nc are the number of chicks in the 
respective groups;
st 2 and sc 2 are the 
variances of the test and control groups, respectively.
The variances are calculated as follows:
[GRAPHIC] [TIFF OMITTED] TR01JA93.413

where:
[Sigma]x is the sum of the logs of the pericardial fluid volumes;
[Sigma]x \2\ is the sum of the squares of the logs of the pericardial 
fluid volumes for either the test t or control c group data.


The test sample is judged to contain chick-edema factor if the 
calculated ``t'' exceeds +1.3 and the mean log of the pericardial fluid 
volume obtained from the negative control group multiplied by 100 is 
less than 1.1461.
    (iii) ``Other factors toxic to chicks'' referred to in paragraph 
(b)(3) of this section shall be determined during the course of the 
bioassay test described in paragraph (b)(4)(ii) of this section, on the 
basis of chick deaths or other abnormalities not attributable to chick-
edema factor or to the experimental conditions of the test.
    (c) It is used or intended for use as a supplementary source of fat 
for animal feed.
    (d) To assure safe use of the additive, in addition to the other 
information required by the act:
    (1) The label and labeling of the additive, and any feed additive 
supplement, feed additive concentrate, feed additive premix, or complete 
feed prepared therefrom shall bear:
    (i) The name of the additive.

[[Page 508]]

    (ii) The designation ``feed grade'' in juxtaposition with the name 
and equally as prominent.
    (2) The label or labeling of the additive and any feed additive 
supplement, feed additive concentrate, feed additive premix, or complete 
feed prepared therefrom shall bear adequate directions for use.

[41 FR 38652, Sept. 10, 1976, as amended at 47 FR 9397, Mar. 5, 1982; 54 
FR 18281, Apr. 28, 1989]