Micotoxins in animal feed detected from May/1997 to March/2001 at the Veterinary Toxicology Laboratory of State University of Londrina - Londrina - Paraná State

Abstract

Micotoxins are toxic secondary metabolites that have no biochemical significance in fugal growth and development. Recommendations for micotoxin control include constant monitoring by a program of harvest samples and micotoxin analysis. A total of 436 samples were analyzed from May 1997 to March 2001 to detect the following micotoxins: aflatoxins B1, B2, G1 and G2, zearalenona and ocratoxina A. The thin layer chromatography technique was used (CCD). Most of the analyses performed were of maize grains and silage, 273 samples, representing 62.6% of the total (436) and this number may be linked to the type of animal production, Holstein cows, that most use this type of food, as most of the samples came from dairy farms in the north of Paraná state. Zearalenona was the most detected micotoxin with 57.5% positive samples representing 28% of all the substrates. The aflatoxin represented 36.3% of the total of positive samples and 17.7% in the substrates. When the number of samples received for analysis and positiveness are correlated, it was observed that there was a greater occurrence of positive analyses in the summer and autumn, 64.3% and 73.5%, respectively. The results obtained reflect the type of animal production in this region and the climatic phenomena that occurred 1997-2001 such as heavy rainfall and abrupt temperature variations that eased fungus development and consequently the appearance of micotoxins.