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Scientific Opinion on the safety and efficacy of Cylactin® (Enterococcus faecium) as a feed additive for cats and dogs


Panel members at the time of adoption

Gabriele Aquilina, Alex Bach, Vasileios Bampidis, Maria De Lourdes Bastos, Gerhard Flachowsky, Josep Gasa-Gasó, Mikolaj Antoni Gralak, Christer Hogstrand, Lubomir Leng, Secundino López-Puente, Giovanna Martelli, Baltasar Mayo, Derek Renshaw, Guido Rychen, Maria Saarela, Kristen Sejrsen, Patrick Van Beelen, Robert John Wallace and Johannes Westendorf.

Competing interests: One member of the Panel did not participate in the discussion on the subject referred to above because of potential conflicts of interest identified in accordance with the EFSA policy on declarations of interests.


Cylactin® is the trade name for a preparation of Enterococcus faecium. It is currently authorised for use in chickens for fattening, pigs for fattening, piglets, sows, calves, turkeys for fattening, cats and dogs in various formulation. The product is intended for use with dogs at a minimum dose of 4.5 x 106 and a maximum dose of 2.0 x 109 CFU/kg feed and with cats at a minimum dose of 5.0 x 106 and a maximum dose of 8.0 x 109 CFU/kg feed. The Cylactin® strain does not contain marker genes typical of hospital-associated isolates responsible for clinical infections and is susceptible to clinically relevant antibiotics, except for kanamycin, which is considered of no concern. Cylactin® is safe for dogs and cats at the recommended dose range. The additive is not a skin/mucosal irritant or a skin sensitiser. As this formulation has a large particle size and the dusting potential is low, the potential for exposure via the respiratory route is considered minimal. Three studies carried out in dogs demonstrated that the additive has the potential to produce a beneficial effect in dogs, when added to feedstuffs at a dose of 2.5 x 109 CFU kg, by increasing the intestinal or serum concentration of IgA. Cylactin® showed inconsistent effects on faecal quality in three studies in which cats were fed the additive at the dose of 7 x 109 CFU/kg of feed.

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