Effects of dietary n-3 polyunsaturated fatty acids and ... - FINS

1 st WorkshopXIII International Feed Technology SymposiumDYNAMICS OF MICROBIOLOGICAL ANDMYCOTOXICOLOGICAL CONTAMINATION OF POWDEREDAND PELLETED CALF FEED MIXTURE IN WINTERCONDITION STORAGE110Aleksandra Bočarov-Stančić 1 , Milan Adamović 2 , Vladimir Pantić 1 , Bisera Dolić 1 ,Marina Vukić-Vranješ 31 "Center for Bio-Ecology"d.o.o.,Petra Drapšina 15, 23000 Zrenjanin, Serbia2 Institute for Technology of Nuclear and Other Raw Materials, Franše d' Eperea 86,11000 Belgrade, Serbia3 Institute for Applied Science in Agriculture, Bul. despota Stefana 86b, 11000 Belgrade,SerbiaABSTRACTChanges in microbiological and mycotoxicological quality of powdered and pelleted calffeed mixture were investigated during 150 days storage period. The analysis wereperformed at the production day (day 0), after 45 days, 90 days and 150 days of thestorage in calf farm conditions. Total count of bacteria was significantly higher inpowdered mixture than in the pelleted one during the entire storage period. Regardingthe yeast and mold count in powdered and pelleted samples the results were alsosignificantly higher in the powdered one. After prolonged storage period (90 and 150days) mold and yeast number decreased in powdered mixture on less then 10/g. Besidesthat, the number of identified fungal species was much lower in the pelleted calf fodder(6) than in the powdery one (17). The only common species found in the both types oftested samples were: Absidia corymbifera, Aspergillus ochraceus, Cladosporiumherbarum, Fusarium subglutinans, F. verticillioides and one unidentified Aspergillusspecies.The dominant fungal genera in powdered calf feed mixture were: Fusarium (3species), Aspergillus (5 species) and Acremonium (2 species).Although potential producer of aflatoxin B1 – A. flavus was determined in powderedsample mycotoxicological investigations demonstrated the absence of this mycotoxin.Fusariotoxin zearalenone was found after prolonged storage period (90 and 150 days) inconcentrations ranging from 0.368 to 0.736 mg/kg in powdered sample, and from 0.221to 0.442 mg/kg in the pelleted one. The contamination of calf feed mixtures with thismycotoxin was expected because potential producers of zearalenone F. oxysporum andF. subglutinans were observed in powdered and pelleted samples. Type A trichothecene– T-2 toxin was detected in the analyzed fodder mixtures only at the production day(0.337 mg/kg).Key words: storage, calf feed, pelleting, microbiological and mycotoxicological qualityINTRODUCTIONThe main preoccupation of feed industry nowadays is the production of safe andhygienic correct fodder mixtures. It is conditioned by the quality of raw materials,