Scientific Opinion on the efficacy of Bactocell ( Pediococcus acidilactici) when used as a feed additive for fish

Bactocell is a feed additive based on viable cells of a strain of Pediococcus acidilactici. This product is already authorised for several species including salmonids. EFSA was requested to assess the efficacy of Bactocell when used as a zootechnical additive (other zootechnical additives) in all fish. The FEEDAP Panel in an earlier opinion concluded that the additive was able to produce a beneficial effect by increasing the number of well-conformed salmonids. However, in the absence of any information on the mode of action, the Panel was unable to predict whether the additive would be effective in non-salmonid fish. In two studies performed with seabass, deformation of the spine was assessed by histological examination and image analysis, and in one study mineralisation was examined using a semi-quantitative staining method of calcification in the whole body. These showed that Bactocell has the potential to produce a beneficial effect in development, increasing the proportion of well conformed fish. The effects seen were comparable to those seen earlier in salmonids. Taking the data on seabass and salmonids together, the FEEDAP Panel concludes that Bactocell has the potential to reduce bone deformation in developing fish at the dose of 1 x 109 CFU/kg of complete feedingstuffs.