Photobacteriosis ( Photobacterium damselae subsp. Piscicida ) and cl assical vibriosis (Vibrio anguillarum O1) are two bacterial diseases that have the potential to cause problems for farming of sea bream. Safe and efficacious vaccines, including A lpha J ect micro 2000, for prevention of photobacteriosis and vibriosis in sea bass (Dicentrarchus labrax) have been commercially available many years but no vaccine for sea bream (Sparus aurata ) has been licensed. The aim of this study was to investigate under controlled laboratory conditions, the safety of A lpha J ect micro 2000 after intraperitoneal (IP) administration to sea bream of the minimum recommended weight at vaccination. Fish groups of 10 - 12 g and >12 - 15 g were IP vaccinated with the recommended dose of the vaccine. The study groups were observed daily for a bnormal behaviour and mortality throughout the study period of 12 weeks post vaccination (wpv). Local reactions (adhesions and melanisation) and amount of vaccine residues were evaluated according to Pharmaq scale for local reactions in sea bass and sea bream after IP vaccination, 3 -6- and 12-weeks post vaccination. I ndividual weights in the study groups were measured at vaccination and at 3, 6 and 12 wpv for assessment of growth.
No mortality post vaccination was observed in any vaccinated group. The severity of adhesions was quite similar between vaccine groups at the different evaluation time points, with 1. 4 mean adhesions score for both groups at 12 wpv. The observed severity of adhesions was mild. No melanin was observed on the abdominal organs or the abdominal wall for any group at termination. Moderate amounts of vaccine residues were detected at termination (score of 1-2 ).
The growth of both vaccinated groups was considered normal and as expected under laboratories conditions , showing that vaccination with oil-adjuvanted vaccines containing inactivated antigens of P . damselae and V. anguillarum O1 did not result in any growth reduction in sea bream in the 12 weeks observation period of this study.
Safety was satisfactorily demonstrated until 12 wpv for the two investigated fish sizes of sea bream IP vaccinated with Alpha Ject micro 2000.