Probiotics for shrimp larviculture: review of field data from Asia and Latin America Olivier Decamp 1 , David J W Moriarty 2,3 & Patrick Lavens 2 1 INVE Technologies NV, Dendermonde, Belgium 2 INVE Aquaculture Health, Dendermonde, Belgium 3 Centre for Marine Studies,The University of Queensland, Queensland,4072 Australia Correspondence: O Decamp, INVE Technologies NV, Hoogveld 93,9200 Dendermonde, Belgium. E-mail: o.decamp@inve.be Abstract Disease problems have emerged as major constraints in aquaculture production. The prophylactic applica- tion of antibiotics is expensive and detrimental, i.e. se- lection of bacteria that are drug-resistant or more virulent and the prevalence of drug residues in reared animals. Probiotics, which compete with bacterial pathogens for nutrients and/or inhibit the growth of pathogens, could be a valid alternative to the prophy- lactic application of chemicals. A mixture of speci¢c Bacillus strains was designed following a research programme on the ability of numerous Bacillus strains to inhibit a range of pathogenic Vibrio strains, to grow under conditions prevailing in shrimp hatcheries and to degrade waste products.These strains were then in- cluded in bioassays and challenge tests in order to con¢rm the lack of toxin production and pathogeni- city to humans, target organisms and the environ- ment. Here, we report on the performance of a commercially available mixture of Bacillus strains (SANOLIFE s MIC), using data from Asian and Latin- American hatcheries, with Penaeus monodon (Fabri- cius 1798) and Litopenaeus vannamei (Boone 1931). These results show that probiotics may be a suitable alternative to the prophylactic use of antibiotics. Ob- viously, minimizing the risk of vibriosis demands a multi-disciplinary approach, including good hygiene and sanitation measures to reduce the input of poten- tial pathogens, as well as a suitable farm management. Keywords: probiotic, Bacillus, Vibrio , larviculture, disease Introduction Major losses in penaeid hatcheries are due to general problems with water quality control and Vibrio spp., which are opportunistic bacteria. Vibrio spp. are nor- mally present in the culture facilities, as well as in the larval gut £ora and in the live feed and they usually cause disease under sub-optimal culture conditions. The application of antibiotics is expensive and detri- mental, i.e. selection of bacteria that are drug-resis- tant or more virulent, prevalence of drug residues in reared animals (Moriarty 1999; Gilbert & McBain 2003; Holmstr˛m, GrÌslund, Wahlstr˛m, Poung- shompoo, Bengtsson & Kautsky 2003). Probiotics, which compete with bacterial pathogens for nutri- ents and/or inhibit the growth of pathogens, could be a valid alternative to the prophylactic application of chemicals, antibiotics and biocides (Moriarty 1999). In addition, the role of microorganisms in water quality improvement is well documented. Much doubt on the e⁄cacy and safety of probiotics on the market comes from the use of ine¡ective bacterial species, unrealistic claims, lack of scienti¢c evidence and poor quality control during production of the ¢nished product, or inappropriate delivery methods leading to contamination or reduced perfor- mance (Temmerman, Huys, Pot & Swings 2003). The development of suitable probiotics is not a simple task and requires empirical and fundamental re- search, full-scale trials, as well as the development of appropriate monitoring tools and controlled production. As Priest (1993) states: ‘species such as Bacillus li- cheniformis (Weigmann 1898) and B. subtilis (Ehren- berg 1835) are universally distributed and dominate the marine £ora to such an extent that they could be considered primary inhabitants of the oceans ’ . . .. Bacillus (Cohn1872) generally occur more frequently in sediments than in the water column; at lower le- vels, Bacillus spores may account for up to 80% of the total heterotrophic £ora’. There are many reports Aquaculture Research, 2008, 39, 334^338 doi: 10.1111/j.1365-2109.2007.01664.x r 2008 The Authors 334 Journal Compilation r 2008 Blackwell Publishing Ltd