Cooling, cryoprotectant and hypersaline sensitivity of penaeid shrimp embryos and nauplius larvae

The sensitivity of embryos of the penaeid shrimp, Trachypenaeus byrdi, to c ooling, cryoprotectant exposure (dimethyl sulfoxide : DMSO, sucrose, methan ol and glycerol), and hypersaline treatment was assessed in order to gain b asic knowledge for cryopreservation procedures. In addition, cooling and DM SO exposure was evaluated in Penaeus stylirostris and T. byrdi nauplii. Mor ulae and advanced embryos (setae development stage) showed tolerance to coo ling at 10 degreesC, but were very sensitive to 0 degreesC exposure. Methan ol exposure at 12 degreesC up to 2 M, was non-toxic for advanced embryos. D MSO toxicity was intermediate; no statistical decrease in survival(P > 0.05 ) was measured at 0.5 M, Sucrose and glycerol were toxic to both embryo sta ges over 0.25 and 0.5 M, respectively. Morulae were more resistant to hyper saline treatment at 55 ppt than advanced embryos. Nauplii showed a better t olerance to cooling and DMSO exposure than embryos. These findings are bein g applied to develop a cryogenic protocol for penaeid embryos. (C) 2001 Els evier Science B.V. All rights reserved.