Marine finfish aquaculture often suffers from mortality, diseases, malformation and low yield in larviculture stage s, often due to the negative interactions between fish and opportunistic bacteria in the environment and live feed . It has been demonstrated that stable microbial environments, depends on the ratio of slow-growing k-selected microbiota to rapid-growing r-selected bacteria, which at higher ratio, the stable environment can improve the growth and survival of marine larvae. Production systems with unstable r-selected microbiota are more susceptible to pathogenic bacterial growth, while, in stable microbiota environments, the health of animals is promoted. In rearing conditions , microbes are introduced by feed, water and the larvae themselves. The bacterial population also depends on available organic materials in the system. Due to slow microbial maturation under normal rearing conditions, more pathogenic bacteria such as Vibrio spp. can generally be observed. Hence, u nderstanding the host-microbe interactions can help decrease disease outbreaks , need for chemotherapeutants, and increase overall productivity.
C opepods are an increasingly important live feed in marine fish larviculture , adding to the list of potential bacterial vectors . Copepods play an important role in microbial loops due to their feeding habits , releasing of organic materials, and their chitin-based exoskeleton, providing an ideal substrate for bacterial accumulation and growth. Copepods can be colonized by bacteria, especially around oral, anal , intersegmental parts, and the intestine. Some research has been conducted on copepod microbial loading. However, as an emerging live feed in larviculture applications, there remains an unmet need to further understanding the microbial community dynamics during copepod mass production , which can affect copepod p roduction, and fish larvae performance.
This study aimed to investigate and understand the impact of probiotics on copepod (Apocyclops panamensis) productio n, water quality, microbial community and Vibrio sp. reduction in mass production systems. The impact of probiotics , on copepod and water microbial changes w ere also studied .