Treatment of the early life
stages of scallop (Pecten maximus) with antimicrobial agents;
searching for an alternative to chloramphenicol
L. Torkildsen, R. Coyne, O.B. Samuelsen, T. Magnesen, Ø. Bergh-2002
Aquaculture
International, 10(5):
399-409
Abstract:
High mortality rates are often observed in rearing
the early stages of the great scallop, Pecten maximus. The addition
of antibacterial agents has been necessary to improve larval survival.
However, as one antibacterial agent, chloramphenicol, is banned in Norway
and Europe the aim of this study is to investigate alternative antibacterial
agents. The therapeutic agents investigated in this study were florfenicol,
oxytetracycline, oxolinic acid, neomycin and Pyceze. The mean minimum
inhibitory concentration (MIC) values were determined for oxytetracycline,
oxolinic acid and Pyceze against bacteria isolated from scallop larvae. Two
types of treatment regime were investigated on an intermediate scale (20 L).
One regime involved continuous exposure of scallop larvae to the therapeutic
agent while the other involved a short exposure lasting two hours. All
intermediate scale treatments were performed in parallel to large-scale
production (800 L) treatment with chloramphenicol. Of the therapeutants
investigated, oxolinic acid was the most effective, although only at high
concentrations. The short exposure of two hours was ineffective for all
therapeutics.
(Institute of
Marine Research, Division of Aquaculture, Nordnes, N-5817, Norway, e-mail: lise.torkildsen@imr.no)