Diet contaminated with ochratoxin A at the highest level allowed by EU recommendation disturbs liver metabolism in weaned piglets

Abstract

Ochratoxins, are toxic fungal metabolites produced by certain moulds of the generaAspergillus andPenicillium that grow on a wide range of raw food commodities. The most relevant toxin is ochratoxin A (OTA) and the European Commission has established guidance values for OTA concerning complementary and complete feeding stuff recommending that for pigs a maximum concentration of 0.05 mg/kg. These guidance values represent only a recommendation of the Commission and the establishment of a legal regulation needs additional toxicological data generated from farm animal experiments. The aim of this paper was to investigate the effect of OTA – at the recommended EU guidance value of 0.05 mg/kg – on liver health. For this purpose, twelve crossbred, weaned piglets were fed for 33 days a maize-soybean-meal-based diet contaminated or not with 0.05 mg/kg OTA. Blood plasma samples were collected at the end of this period and subjected to biochemical analyses, whereas liver samples were analysed for cytokine concentration (ELISA), enzyme activity and expression of selected genes (qRT-PCR) involved in liver metabolism. Exposure to OTA resulted in a significant decrease in the concentrations of total protein, albumin and nitric oxide in plasma, and interleukin-6 in the liver. OTA exposure also resulted in a significant increase of alanine aminotransferase and triglycerides in plasma and of superoxide dismutase in the liver. In conclusion, the administration of 0.05 mg/kg of OTA, to weaned piglets for a period of 33 days caused measurable hepatocellular injury in the toxin-exposed. Additionalin vivo studies should be performed with larger numbers of animals in order to confirm our results and to provide robust data for the establishment of safe concentrations of OTA in swine feeds.