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00004 ăWOS:000367853300006; International audience; This study examined the effect of a commercial mix of Bacillus sp. on survival, growth and digestive enzyme activities of Florida pompano, red drum and common snook. Larvae were fed either live feed enriched with Algamac 3050 (Control), Algamac 3050 and probiotics (PB), or the previous diet combined with a daily addition of probiotics to the tank water (PB+). Survival was not affected by the treatments for any of the species. At the end of the pompano and snook trial, standard lengths of larvae from the PB and PB+ treatments were significantly greater than for the control larvae. Microbiological analyses were performed at the end of the pompano trial, and numbers of presumptive Vibrio were not a concern in the system. For both pompano and snook, trypsin-specificactivity was higher in PB and PB+ larvae compared with the control larvae. Similarly, alkaline phosphatase activity was higher for the pompano larvae fed the PB and PB+ treatments and for the snook larvae fed the PB+ treatment compared with the control larvae. This experiment suggests that a mix of Bacillus sp. can promote growth through an early maturation of the digestive system during the early larval stages of pompano and snook.

In the past the oceanic environment has often been compared with terrestrial deserts and until today relatively little is known about the ecology of the high seas. Within the present study pelagic oceanic communities of cephalopods and fish in the subtropical North Atlantic were investigated, and it was analysed at different spatial scales how these communities varied in response to physical gradients and hydrographic processes. First, the influence of the subtropical convergence zone in the Sargasso Sea on the distribution of early life stages of cephalopods was determined. This large-scale front turned out to represent a distinct faunal boundary, with higher diversity and abundance values in the northern part of the Sargasso Sea compared to the southern area. Second, mesoscale distribution patterns of paralarval cephalopods and larval fish were described at Great Meteor Seamount in relation to the specific hydrographic features, as e.g. the Taylor cap. Processes structuring the pelagic communities were identified and their impact evaluated by different multivariate statistical techniques. Fish and cephalopods were similarly influenced, although the retention potential at the seamount was much more pronounced for larval fish. Third, the diurnal vertical migration behaviour of juvenile and adult cephalopods was investigated from samples collected at three seamounts of different topographic morphology. A logistic regression model was developed to demonstrate the probability of occurrence in relation to daytime and catch depth. Because of the species-specific vertical distribution the seamounts represented a topographic obstacle, resulting in an impoverished fauna at shallower water depth.