Safety and efficacy of AveMix® XG 10 (endo-1,4-beta-xylanase and endo- 1,3(4)-beta-glucanase) for use as feed additive for chickens for fattening

Following a request from the European Commission, the European Food Safety Authority (EFSA) was asked to deliver a scientific opinion on the safety and efficacy of AveMix® XG 10 when used as a feed additive for chickens for fattening. The additive AveMix® XG 10 is a preparation of endo-1,3(4)-β-glucanase (E.C. 3.2.1.6) and endo-1,4-β-xylanase (E.C. 3.2.1.8) produced by two strains of Trichoderma reesei. The additive is produced in solid and liquid forms, and is intended for use as feed additive for chickens for fattening at a recommended dose of 4000 XU and 660 BGU kg-1 complete feedingstuffs. The solid and the liquid forms of the product are considered to be essentially equivalent in terms of safety for the target animals, consumers and the environment, and efficacy when used in diets for chickens for fattening at the same dose. The FEEDAP Panel notes that the ratio of the two enzymes in the additive used for animal studies differed from that specified by the applicant. The following conclusions are based on the formulation as analysed and the corresponding increased enzyme concentrations in complete feedingstuffs On the basis of the results from three efficacy studies made with chickens for fattening, in which significant increases in body weight gain were observed, the FEEDAP Panel concludes that there is evidence to support the efficacy of AveMix® XG 10 at the dose of 4000 XU kg-1 and 900 BGU kg-1 complete feedingstuffs. A tolerance study performed with a 100-fold overdose of the product did not produce any adverse effects. Consequently, the FEEDAP Panel concludes that enzyme concentrations resulting from the supplementation of AveMix® XG 10 at 100 mg kg-1 feedingstuffs are safe for chickens for fattening. The results of the studies on genotoxicity and the 90-day study do not indicate any reason for concern regarding consumer safety from the use of AveMix® XG 10 as a feed additive. From the results of tests on the individual enzyme concentrates contained in the additive, AveMix® XG 10 is not considered to be a dermal or eye irritant. However, it is considered to be both a dermal and respiratory sensitiser and should be handled accordingly. The active substances of AveMix® XG 10 are proteins and as such will be degraded/inactivated during the passage through the digestive tract of animals. Therefore, no risk for the environment is expected.