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The supply of macroalgal feed materials for abalone aquaculture is threatened by increasing costs, limited availability. and the allocation of seaweed resources for other purposes. The use of biofouling Sargassum horneri (SH) as additional macroalgal biomass for abalone has been studied, albeit full inclusion is discouraged due to low utilization. This study applied heat treatment and fermentation to increase the nutritive value of SH meals for the aquaculture feed industry. Untreated (UN) as control, heat treated (HT, 121[degrees]C for 20 min), and fermented (FE, 10' CFU/mL each of Bacillus sp. SJ-10 and Bacillus sp. KRF-7) SH meal was fed to the abalone (11.60 [+ or -] 0.02 g body weight and 42.98 [+ or -] 0.53 mm shell length) for 8-wk growth trial. The results showed that there is no apparent difference in the growth performance (body weight and shell length morphometries) and survival of abalone given experimental diets (P > 0.05). The crude protein, lipid, and ash composition of edible abalone flesh were similarly unaffected (P > 0.05). The gut microbiota profile of abalone was analyzed through next-generation sequencing. The [alpha]-diversity indicators (microbial richness and abundance) were statistically similar (P > 0.05). and the [beta]-diversity of operational laxonomic units revealed short distances within samples and clustering among diet groups. The core phyla (Fusobacteria, Proteobaeteria. Tenericutes) and genera (Psychrilyohacter, Vibrio, Mycoplasma) known to inhabit the gut of abalone predominantly were likewise identilied irrespective of diets; however, there is a difference in their relative abundance. Genus Psychrilyohacter was relatively abundant in UN and FE compared with HT, whereas Vibrio and Mycoplasma had higher abundance in FE and HT-fed abalone, respectively. Taste sensory attributes were discriminated in the abalone meat using an electronic tongue. Principal component analysis of sensor scores revealed several overlapping points, resulting in a negative discrimination index (-184). which means no apparent difference in the general taste profile was detected. Furthermore, the taste screening matrix through radar mapping revealed slight intensity differences in the umami. saltiness, and sourness flavor. Overall, the methods used for heat treatment and fermentation procedures herein were ineffective in improving the nutritive value of seaweed meal for abalone. KEY WORDS: abalone, gulfweed. heat treatment, fermentation. Haliotis discus harmed, Sargassum horneri, INTRODUCTION The abalone (Haliotis spp.) is an ecologically and economically important marine gastropod mollusc worldwide. They are found in tropical and temperate regions, particularly in the low intertidaj zone of [...]

The experiment was conducted to evaluate the supplementary effects of gamma aminobutyric acid (GABA) and sodium butyrate (SB) when a graded level of fish meal (FM) was replaced with soy protein concentrate (SPC) in diets for juvenile red seabream ( Pagrus major ). A control diet was designed to contain 60% FM (F60). Two other diets were formulated by reducing FM levels to 40% and 20% with SPC (F40 and F20). Six more diets were formulated by adding 0.02% GABA or 0.2% SB to each F60, F40 and F20 diets (F60G, F60S, F40G, F40S, F20G and F20S). Each diet was randomly assigned to a triplicate group of fish (5.52 g/fish) and provided for eight weeks. Final body weight, weight gain and specific growth rate of fish fed F60G, F60S, F40G and F40S diets were comparable and significantly higher ( p < 0.05) than other groups. The growth of fish fed SB-containing diets was significantly increased ( p < 0.05) compared to fish fed the respective control diets. The feed efficiency and protein efficiency ratios were significantly higher ( p < 0.05) in the fish fed all diets containing 60% and 40% FM compared to F20 and F20G groups. The F40S diet resulted in the highest feed utilization values. The F20S group exhibited significantly higher ( p < 0.05) feed utilization than the F20 and F20G groups. Serum lysozyme activity was significantly higher ( p < 0.05) in fish fed the GABA- and SB-containing diets compared to the F20 group. The F60S group exhibited the highest lysozyme activity which was significantly higher ( p < 0.05) than in the F20 and F40 groups. Therefore, the growth performance, feed utilization and innate immunity of red seabream can be enhanced by dietary supplementation with GABA or SB in low-FM diets containing SPC. The FM level in the juvenile red seabream diet can be reduced to 40% with SPC and GABA or SB while maintaining performance better than a diet containing 60% FM.