The monitoring of fungal toxins has become indispensable in the feed industry and animal production. Until recently, most of the available analytical methods only covered single classes of mycotoxins such as aflatoxins, type B trichothecenes or fumonisins. Over the past decade, the sensitivity of liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) has increased by 200 fold and it is quickly becoming the reference for multiple mycotoxin detection. The tool’s power and accuracy allow for more refined detection of a greater number of mycotoxins and metabolites than ever before. Available commercially for the first time in 2014, next-generation mass spectrometry provides a more detailed picture of the contamination of different feed materials using Spectrum 380® to measure more than 380 mycotoxins and other secondary metabolites in one go.
Better detection in the field
By offering more powerful and accurate mycotoxin detection, Spectrum 380® can help farmers to understand situations that they encounter in the field that are not readily revealed by traditional techniques. Two case studies illustrate the benefits of better detection.
Co-exposure is the norm
A South African cattle farmer noticed that the animals were experiencing tremor problems in their hind legs. Black spots on the barley in the feed raised suspicion of an Aspergillus contamination. The farmer conducted regular routine analysis that revealed only low levels of fumonisins, which did not explain the tremor problem. Multiple mycotoxin analysis using Spectrum 380® showed quite a different picture: the presence of other mycotoxins at high concentrations including 7 parts per million of cytochalasin E and 500 parts per billion of patulin, a mycotoxin with neurotoxic effects.
While this is just one example, we know from decades of research on mycotoxins that they tend to occur in groups. This phenomenon, known as co-exposure, is quite common as demonstrated by recent data.
For the first time the results of Spectrum 380® analysis of 814 raw materials and finished feed samples collected worldwide are included in the 2014 BIOMIN Mycotoxin Survey. On average, 30 different metabolites per sample were detected (Figure 1) based on data for all regions except Asia. The number of mycotoxins per sample ranged from 4 to 75. In 98% of samples more than 10 metabolites were found. (Using older mycotoxin detection methods, quantifying 380 metabolites in 814 samples would have required 309,320 separate analyses, versus 814 analyses with Spectrum 380®).
Figure 1. Distribution of 814 samples according to number of mycotoxins per sample.
Source: 2014 BIOMIN Mycotoxin Survey
Compound (synergistic) effects
A Brazilian pig farmer observed ear necrosis, a well-known symptom of deoxynivalenol contamination, in his pigs. Mycotoxin analysis using enzymelinked immunosorbent assay (ELISA) showed only very low levels deoxynivalenol in the three feed samples analyzed— too low to account for the ear necrosis. Multiple mycotoxin analysis using Spectrum 380® showed that in reality his animals faced a total concentration of mycotoxins ten times higher than ELISA indicated. In addition to deoxynivalenol, the feed samples contained other type B trichothecenes such as nivalenol and the glucosylated form of deoxynivalenol (DON-3-glucoside), and members of the culmorin family, known to intensify the effects caused by deoxynivalenol.
This case reflects the knowledge that some mycotoxins display synergistic effects: the adverse consequences of each mycotoxin (separately, often in a lab) are aggravated by multiple mycotoxin occurrence in the field and thus result in greater overall harm to the animal.
Informing the research agenda
Spectrum 380® analysis reveals that the major mycotoxins, present in over 40% of cases, account for just 6 of the 32 most common mycotoxins in the 814 samples tested (Figure 2). The others, sometimes referred to as emerging mycotoxins or exotic metabolites, are less well-understood in part because not enough data is available for toxicological studies to be conducted.
Figure 2. The 32 most common metabolites found in 814 worldwide feed and raw material samples tested (present in more than 40% of samples). Red-colored bars indicate well known mycotoxins. For the purpose of data analysis, limit of quantification (LOQ) level for each mycotoxin was adopted to determine positive samples.
Source: 2014 BIOMIN Mycotoxin Survey
Figure 2 also shows that 95% of the 814 feed samples tested positive for the structurally-related group of beauvericin and enniatins. In December 2014, the European Food Safety Authority (EFSA) published a new scientific opinion on the health risks of these toxins in food and feed highlighted the need for more data, especially in relation to their co-occurrence and possible combined effects with other Fusarium toxins.
The availability of LC–MS/MS and multiple mycotoxin detection will shed considerable light on mycotoxin analysis and the mycotoxin situation on the field. Using multiple mycotoxin detection technologies makes sense because of several things we know about mycotoxins.
First, co-exposure is quite common. Second, there are negative synergistic effects among certain mycotoxins. Further toxicity studies are required to gain sufficient data on the impact of exotic and emerging mycotoxins in animal health and performance. Given the diversity of mycotoxins coming to light, effective mycotoxin risk management must rely upon the most up-to-date scientific knowledge and multiple modes of action to protect against agriculturally relevant mycotoxins.