Results of one-year investigations of the contamination of dairy cattle feed and raw milk with moulds and mycotoxins

Abstract

The contamination of 98 dairy cattle feed samples with moulds and mycotoxins (AB1, OTA, ZEA) was investigated. The contamination of 80 raw milk samples with aflatoxin M1 was also tested. Determination of total viable counts per 1g of feed was performed using Koch's standard method. The content of AB1, OTA and ZEA in feed, as well as aflatoxin M1 in raw milk samples, was determined by VICAM fluorimetric method. Results showed that 91% of all tested samples was contaminated with moulds, and total viable mould count per gram ranged from 10 (corn silage-spring) to 4.9 x 10 6 per gram (dried alfalfa-winter). The isolated moulds belong to 20 genera and 72 species. Results of mycotoxicological investigations showed that 42 samples of total 98 tested, were contaminated with mycotoxins. The most frequent was OTA (24 samples, 20.00-210.00 µg/kg) followed with ZEA (12 samples, 250.00-980.00 µg/kg) and AB1 (3 samples, traces-18.50 µg/kg). Aflatoxin M1 in raw milk samples wasn't found.