This week saw the European Food Safety Authority (EFSA) publish its findings on the Dutch company’s ensiling product that contains single strains of Saccharomyces cerevisiae, Lactobacillus plantarum and Lactobacillus casei - the EU risk assessor said it remains impossible to establish a minimum specification for the aditive or a minimum effective dose.
Jan Feersma Hoekstra, managing director of Agriton, told us “EFSA acknowledged that in independent studies, with a dose of 80 ml per ton, the product has showed its claimed positive effect.”
However, he said, the sticking point preventing EFSA from establishing a minimum effective dose for the silage product is its refusal to accept the methodology applied by the company: “An accurate count number per ml cannot be given by FISH methods according to EFSA," said Hoekstra.
Agriton used the Fluorescence in situ hybridization (FISH) approach to characterize the silage additive – a tool that comes highly recommended by its advisors – Wageningen and Groningen universities, he explained.
“The international literature published on the FISH method shows it gives a more accurate count of microbes than the EFSA recommended one,” added Hoekstra.
Nevertheless, EFSA determined “As indicated previously, the FISH methods used are not specific for viable cells and so the results obtained are of questionable value.”
The Authority said the FISH values obtained by Agriton could not be equated to colony-forming units (CFU), the basis of any authorization.
The safety of the silage additive for consumers, users, the environment and target animals was established in a previous EFSA FEEDAP panel opinion in 2013.
However, EFSA said the efficacy studies provided at that time showed no evidence that the additive had the potential to conserve nutrients and so improve the production of silage.
It did see some evidence for an effect on aerobic stability, but because of the inherent variability in the additive mix, it said it was unable to establish a minimum effective dose for the additive.
The Commission allowed the company to submit complementary information to complete the assessment on the characterization and the efficacy and to allow a possible revision of the Authority's opinion on the product, and Agriton sent EFSA a number of additional ensiling studies.
The latest EFSA opinion on the additive can be read here.