Mycotoxins

Mycotoxin Sampling, Testing, and Test Kits

Since mycotoxins are not evenly distributed in grain or in mixed feeds, taking a feed or grain sample which will give a meaningful result in mycotoxin analyses is difficult. Grab samples generally give very low estimates of mycotoxin content. In fact, nearly 90 percent of the error associated with mycotoxin assays can be attributed to how the original sample was collected. This is due to only 1 to 3 percent of the kernels in a contaminated lot containing mycotoxin, and these contaminated kernels are usually not evenly distributed within the lot of grains.

For whole kernel grains, a properly taken composite sample of at least ten pounds is required for a reasonably accurate, mycotoxin analysis. Trucks can usually be sampled with a grain probe, but bins must often be sampled as grain is being withdrawn.

Analytical techniques for the detection of mycotoxins continue to improve. Several commercial laboratories now test for a variety of mycotoxins. Although analytical costs can be a constraint, these costs may be insignificant compared with the economic consequences of production and health losses associated with mycotoxin contamination.

Commercial antibody test kits for screening or quantitation are currently available for aflatoxins, zearalenone, deoxynivalenol (DON), T-2 toxin, ochratoxin A, and fumonisins. These antibody methods, while they are still being improved, are good if used properly. The mycotoxin test kits in Table 7 have been tested and found to perform in a wide variety of laboratories.

Screening of corn for possible aflatoxin contamination using a "black light" was a popular technique 15 to 20 years ago. In spite of the widespread use of black lighting to screen for aflatoxin and other mycotoxins, research has shown that the technique detects materials which are not mycotoxins, and is, therefore, inappropriate. The black light test should never be used for any kind of mycotoxin screening.

The minicolumn is a small column containing silica gel and Florisil (or other adsorbents) to which sample extracts are applied for detection of aflatoxin. Minicolumns were also very popular for aflatoxin screening until antibody-based test kits became widely available over the last few years. If properly used, the minicolumn test is capable of giving good results for aflatoxin under certain conditions. However, like the black light, it has often been mishandled and misused. The minicolumn is no longer recommended.

Better yet, because little is known about the above mycotoxins, and because many unidentified mycotoxins exist, cattle producers should avoid feeding moldy feeds if at all possible.


Table  7. Some of the Commercially Available Mycotoxin Test
Kits
                                                         
 MANUFACTURER           MYCOTOXINS DETECTED   TEST KIT NAME

 Editek                     Aflatoxin            EZ-Screen
 P. O. Box 908              Ochratoxin
 1238 Anthony Rd.           T-2 Toxin
 Burlington, NC 27215       Zearalenone
 Phone:  (910) 226-6311
 Fax:    (910) 229-4471

 International Diagnostic   Aflatoxin(4 Kits)    1. Afla 20 Cup
 System Corp.                                    2. Afla 10 Cup
 2620 S. Cleveland Ave.                          3. Afla  5 Cup
 Suite 100                                       4. Afla B1, 
 St. Joseph, MI 49085                               ELISA Test
 Phone: (616) 428-8400                              
 Fax:   (616) 428-0093      Zearalenone (2 Kits) 1. One Step     
                                                    ELISA,       
                                                    Quantitative 
                                                    Test
                                                               
                                                 2. I. D. Block,
                                                    ELISA        
                                                    Antibody

Neogen Corporation          Aflatoxin            AgriScreen
620 Lesher Place            T-2 Toxin            Veratox
Lansing, MI 48912           Vomitoxin (DON)
Phone:  (517) 372-9200      Zearalenone
         800) 234-5333      Fumonisin
Fax:    (517) 372-2006      Aflatoxin M1
                            Ochratoxin
  
VICAM                       Aflatoxin            Aflatest-P
313 Pleasant St             Fumonisin            Fumonitest
Watertown, MA 02172         Ochratoxin           Ochratest
Phone:  (800) 338-4381      Zearalenone          Zearalatest
        (617) 926-7045
Fax:    (617) 923-8055
  

NOTE: Absolute detection limits of mycotoxin test kits will vary 
and should be examined in relation to the needs of the user.

The use of brand names in this publication does not imply endorsement of the products or services named or criticism of similar ones not mentioned.

Prepared by

Mary Beth Genter, Extension Toxicology Specialist
Winston M. Hagler, Director of NCSU Mycotoxin Laboratory
Jeff A. Hansen, Extension Animal Science Specialist
Bob A. Mowrey, Extension Animal Science Specialist
Frank T. Jones, Editor, Extension Poultry Science Specialist
Matt H. Poore, Extension Animal Science Specialist
Lon W. Whitlow, Extension Animal Science Specialist

http://www.ces.ncsu.edu/gaston/