Open access publications in the SLU publication database

Abstract

The objectives of the study were to evaluate the mycotoxin contamination in feedstuffs and complete feeds for pigs, the capacity of local adsorbents to reduce the adverse effects of aflatoxin B1 in piglets and methods for screening mycotoxins and their metabolites in pig urine as biomarkers for mycotoxin exposure. High incidences of aflatoxins (AF) and zearalenone (ZEA) in feedstuffs and pig feeds (83.3% - 100%) were detected. Aflatoxin B1 was found in 100, 92, 92, 83, 100 and 96%, respectively, of samples of cassava chip, maize, rice bran, broken rice, and complete feeds for growing pigs and sows, with mean concentrations of 0.86, 77.5, 1.3, 1.6, 4.7 and 7.5 µg/kg, respectively. Of these, ZEA was detected in 8%, 33%, 36%, 21%, 67% and 67%, with average concentrations of 10.0, 163.5, 83.1, 31.4, 86.0 and 101.4 µg/kg, respectively. In vitro trial showed that the locally produced bentonite showed an ability to adsorb AFB1 at 1.54 mg/g with the adsorption capacity of 12.7 mg/g. Feeding piglets an aflatoxin contaminated diet gave lower overall average daily weight gain, feed conversion efficiency, albumin and total protein compared to those given an aflatoxin free diet, while mean serum leukocyte and enzyme activities showed significant increases. The inclusion of bentonite at 0.4% or 0.5% in the aflatoxin contaminated diet restored the performance, feed efficiency and abnormal blood profiles of the piglets given AF. The urine analytical methods developed showed high sensitivity for screening ZEA, deoxynivalenol (DON), AF and their metabolites in pig urine with detection limits that ranged from 0.28 to 9.9 ng/ml. The recoveries of ZEA and DON and their metabolites ranged from 86% to 106% and those of AF and its metabolites ranged from 83 to 130%. Urinary excretion of AFB1 in the feeding trial was 30% of the fed dose and the fraction of AFB1 converted to AFM1 in pig urine was 22%. The results from the survey of ZEA, DON and AF and their metabolites in pig urine samples collected from pig farms revealed that the pigs were exposed to ZEA, DON and AF contaminated diets. The toxins and metabolites for ZEA, DON and AF were found in 47, 73, and 80%, respectively, of the 15 urine samples analyzed.