Mycotoxins evaluation of total mixed ration (TMR) in bovine dairy farms: An update

Abstract

The total mixed ration (TMR) is currently a widespread method to feed dairy cows. It is a mixture of raw fodder and concentrate feed that can be contaminated by several mycotoxins. The main aim of this paper was to provide a critical review on TMR mycotoxin occurrence and its usefulness to monitor and control them on-farm. Aflatoxins, zearalenone, deoxynivalenol, T-2 toxin and fumonisins (regulated mycotoxins) are the most prevalent mycotoxins evaluated in TMR. Nonetheless, several emerging mycotoxins represent a health risk at the animal level regarding their prevalence and level in TMR. Even when measured at low levels, the co-occurrence of mycotoxins is frequent and synergistic effects on animal health are still underevaluated. Similar to the animal feed industry, on-farm plans monitoring mycotoxin feed contamination can be developed as a herd health management program. The estimated daily intake of mycotoxins should be implemented, but thresholds for each mycotoxin are not currently defined in dairy farms.

Keywords: Composite feed; Dairy cows; Emerging mycotoxins; Mycotoxin co-contamination; Silage.

Fig. 1

Fungal contamination of maize silages. Legend: White molds (A and B); vertical (C) and horizontal (D) brownish-red stripes into two horizontal trench silos. Beauvericin, enniatin, fumonisin B1 and B2, zearalenone, and deoxynivalenol were detected in these four dairy farms.