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The aim of this study was to screen Bacillus strains from the guts of Scophthalmus maximus, Paralichthys olivacues, Epinephelus coioides and Clupanodon punctatus, for use as probiotics in aquaculture. Eight Bacillus strains were screened, and strain M001 was selected for probiotic study based on its antagonistic activity against multiple aquatic bacterial pathogens including Vibrio anguillarum, V. campbellii, V. vulnificus, V. parahamolyticus, Streptococcus sp. and Edwardsiella tarda. M001 was identified as B. amyloliquefaciens based on the biochemical tests and 16S rRNA gene analysis. In vitro experiments revealed that M001 was able to grow at a wider range of temperature, pH and salinity and was capable to use turbot mucus as nutrient for growth. Additionally, M001 isolate greatly inhibited the growth of V. anguillarum by producing antibacterial substances and was acid tolerance, non-antibiotic resistance and non-harmful. Thereafter, the potential probiotic effect of M001 was tested in turbot by dietary administration of M001 at a dose of 108 CFU g−1 diet for 42 days. No significant differences of weight gain, specific growth rate and feed ratio were found in the M001-diet group of fish compared with control fish, but which increased, respectively, by 5.5%, 4.7% and 7.0% after 42 days of feeding. Several digestive enzyme activities were found to increase significantly in the M001-diet group, including protease and amylase activities in hepatopancreas, protease activity in intestine and lipase activity in stomach ( P < 0.05). Sera superoxide dismutase activity and total protein content ( P < 0.05) were also increased significantly ( P < 0.05) in the M001-diet group. The challenge experiment showed that the M001-diet group of fish showed a relative per cent of survival of 62.7% against V. anguillarim infection. The Bacillus M001 identified from this study has good potential to provide vibriosis control as probiotic feed additive for turbot aquaculture. [ABSTRACT FROM AUTHOR]

• Substituting sorghum for corn in diets reduced feed efficiency of pigs. • Digestibility of gross energy and crude protein was decreased in pigs fed sorghum. • Pigs fed sorghum had greater fecal energy and nitrogen output than those fed corn. • Pigs fed sorghum had lower digestive enzyme activities than those fed corn. • Pigs fed sorghum had lower antioxidant enzyme activities associated with greater malondialdehyde content. This study was conducted to determine whether sorghum as a potential substitute for corn in diets affects the activities of digestive enzymes and antioxidant enzymes in pigs. Sixty pigs (7.3 ± 1.3 kg initial weight) were allotted to 2 diets with 5 replicate pens per treatment according to sex and weight in a randomized complete block design. A corn-based diet (CBD) included 600 g/kg of corn grain during the overall experimental period, and a sorghum-based diet (SBD) consisted of 300 g/kg (day 1–14) or 566 g/kg (day 15–28) of sorghum grain at the partial or complete expense of corn in CBD. Both diets were formulated to contain the same amount of digestible energy and essential amino acids. No differences were observed in average daily gain or feed intake between treatments. However, substituting sorghum for corn in diets tended to reduce (P = 0.087) or reduced (P < 0.05) feed efficiency. Apparent digestibility of gross energy and crude protein was decreased (P < 0.05) in pigs fed the diets comprising sorghum, regardless of the substitute level, associated with the increased faecal excretion of energy and nitrogen. Serum urea nitrogen concentration in SBD was greater than that in CBD (P < 0.05). Pigs fed SBD had or tended to have lower superoxide dismutase and catalase activities and greater malondialdehyde content in serum (P < 0.05) or liver (P = 0.085) than those fed CBD. Amylase and lipase activities were decreased in duodenal mucosa (P < 0.05), and lipase (P < 0.05) and trypsin activities (P = 0.092) in jejunal mucosa were reduced and tended to be reduced in pigs fed SBD. Compared with CBD, SBD increased or tended to increase crypt depth in duodenum (P < 0.05) or jejunum (P = 0.094) coupled with the decrease in villus height/crypt depth in duodenum (P = 0.086) and ileum (P < 0.05). Collectively, sorghum as a dietary substitute for corn changed intestine morphology and reduced activities of digestive enzymes and antioxidant enzymes which may have been responsible for the reduced energy and nitrogen utilization and feed efficiency in pigs. [ABSTRACT FROM AUTHOR]