Pangasius bocourti is an important species in the Mekong Delta basin, especially in Vietnam and Thailand. Pangasius production is approximately 800 000 tons per year with an export value of 1.5 billion USD in 2013. However, farming intensiﬁcation and commercialization have resulted in water pollution causing outbreaks of disease with signiﬁcant economic losses. Antibiotics and chemo-therapeutics have been intensively used in controlling and preventing Pangasius disease. Nonetheless, abuse of antibiotics can lead to the development of antibiotic-resistant bacterial strains, environmental hazards, food safety problems and decline in human resistance to pathogens. The problems outlined above and recent restrictions on the use of antibiotics have resulted in natural immunostimulants, probiotics and prebiotics being considered as an alternative strategy to prevent or control pathogens. The use of these additives can minimize risks associated with chemical drugs and constitutes one of the most promising means in controlling disease in aquaculture.
Probiotics are microbial cells provided via the diet or in the rearing water that beneﬁt the host ﬁsh, ﬁsh farmer or ﬁsh consumer, at least in part, by improving the microbial balance of the ﬁsh. Dietary probiotic supplementation in aquaculture has been reported to improve intestinal balance, growth performance and disease resistance and enhance immune responses. Lactobacillus plantarum is known to produce antimicrobial substances (e.g. plantaricin) active against certain pathogens and is used as a probiotic. Dietary administration of L. plantarum has been demonstrated to improve the growth performance, immune response and resistance to disease in numerous aquatic animals.