Suhaimi D., Wan Syahidah H., Lily Suhaida M.S. and Terjuddin G.
The mycotoxin test data base (2005-2009) of the Veterinary Public Health Laboratory (VPHL), Department or Veterinary Services, Malaysia (DVS) showed that there was a significant increase (51 %) of overall aflatoxin occurrences in various types or animal feed samples, especially those formulated from agricultural by-product, for the year 2008. A study was thus conducted to investigate if there could be some sources of mycotoxin contamination during the period of sample handling. Three different laboratory storage conditions were chosen for the study within a period of fourteen days i.e 4 ?C, room temperature (in light) with mean relative humidity of 62.5%, and room temperature (in dark) with mean relative humidity of 55.7%. The observations showed that there were no significant differences in total aflatoxin, zearalenone, and fumonisin detections in all storage conditions as screened by the ELISA technique. However 11- 50% inconsistencies of the mycotoxin concentrations detected were observed within the samples. The sampling, sample preparation, and analytical steps of the mycotoxin test procedure contribute to the variability of mycotoxin test results. To achieve a more precise estimate of the true lot concentration, the total variability of the test procedure should be reduced i.e. by decreasing the variability associated with each step involved.