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The effects of Bacillus probiotic forms on growth performance and microbiota were examined in black tiger shrimp ( Penaeus monodon). Shrimp were fed for 120 days with one of three diets; a control diet alone or supplemented with either probiotics consisting of live-sprayed Bacillus (LS) or freeze-dried Bacillus (FD). Culturable bacteria counts in the hepatopancreas, intestine and culture water of the three treatments were relatively constant during the experiment. Bacillus numbers in the hepatopancreas and intestines of probiotic-treated groups increased significantly ( P < 0.05) after 30 treatment days and remained relatively constant afterwards while no appreciable changes occurred in the control. Shrimp supplemented with LS and FD contained significantly lower concentrations of Vibrio ( P < 0.05) in the hepatopancreas, intestine and culture water, compared to those in the control group. Shrimp treated with LS and FD probiotic bacteria showed a significant improvement ( P < 0.05) in specific growth rate (SGR) and feed efficiency (FE), compared to those of control group. Probiotic bacteria have the potential to enhance shrimp culture by reducing Vibrio and improving growth performance. [ABSTRACT FROM AUTHOR]

Abstract: The objectives of this study were to determine the effect of cryoprotectants on sperm viability and develop a freezing protocol for long-term storage of P. monodon spermatophores. Spermatophores suspended for 30min in calcium-free saline (Ca-F saline) containing the cryoprotectants dimethyl sulfoxide (DMSO), ethylene glycol (EG), 1,2-propylene glycol (PG), formamide, and methanol at concentrations of 5, 10, 15, or 20% were studied using a modified eosin–nigrosin staining technique. The smallest reductions in apparent sperm viability occurred with DMSO; therefore, a freezing protocol was developed using Ca-F saline containing 5% DMSO. Spermatophores were cryopreserved using three protocols; cooling to a final temperature of −30, −80 or −80°C and immediately stored in liquid nitrogen (cooling rates of −2, −4, −6, −8, −10, −12, −14 or −16°C/min). Frozen spermatophores were thawed (2min) at 30, 60, 70, or 90°C. Successful cryopreservation of spermatophores in liquid nitrogen was achieved by a one-step cooling rate of −2°C/min between 25 and −80°C before storing in liquid nitrogen. Optimal thawing was in a 30°C water bath for 2min; this yielded live sperm after storage in liquid nitrogen for 210 days. Average sperm viability for fresh (97.8±2.9%) and cryopreserved spermatophores held for less than 60 days (87.3±4.1%) did not differ (P >0.05); however, that for spermatophores stored in liquid nitrogen between 90 and 210 days were lower (P <0.05) and varied from 27.3±3.4 to 53.3±4.3%. Thawed spermatophores previously held in liquid nitrogen for less than 62 days fertilized eggs (fertilization and hatching rates of 71.6–72.2% and 63.6–64.1%, respectively) at rates comparable to fresh spermatophores (70.8–78.2% and 66.3–67.8%, respectively). In conclusion, sperm within cryopreserved spermatophores stored in liquid nitrogen retained their viability for up to 210 days. [Copyright &y& Elsevier]