Effects Of P H On Embryonic Development And Larval Growth And Related Enzyme Activity Of Cylina Sinensis

pH is one of the important indicators of aquaculture water environment, too high or too low pH value will directly affect the feeding, growth and Physiological metabolism of cultured organisms. Cyclina sinensis is our country coastal common farming mudflat shellfish. As is known to all, in shellfish large-scale factory breeding algae feeding, and shellfish large number of death and even seawater all can make the pH value increased. On the other hand, ocean acidification will lead to lower pH. Changes in pH resulted in the growth of shellfish, and the embryos and larvae of shellfish were relatively weak in development. Therefore to carry out p H on the embryonic development of larvae of Cyclina sinensis growth test of major significance.This test determined five pH gradient under the condition of Cyclina sinensis embryonic development and larval growth phase of the survival rate, deformity rate and long shell; compared the different p H of clam embryonic and larval growth and morpHological changes of the stress and activities; Determination of the changes in different pH of Cyclina sinensis calcification rate of the influence of different pH conditions of Cyclina sinensis superoxide dismutase(Superoxide dismutase, SOD) and carbonic anhydrase(Anhydrase as a crosslinker CA activity, and then from different aspects of the influence of pH of clam. The p H gradient was 7.4, 7.8, 8.2, 8.6, 9.0, in which the pH8.2 group was normal. Low pH group with mixed air to water and filled with CO2 to reduce the pH of the water, the high pH group by adding appropriate amount of Na2CO3 to raise the pH of the water and the pH value with Rex PHS-2F and Rex PHB-4 type pH detection of. Test water for seawater to add aeration tap water configuration, the test salinity was 15.0±0.2, the test temperature control at 25.0±0.1. 1.Effect of pH on the embryonic development of Cyclina sinensisDetermination of Cyclina sinensis during embryonic development in survival rate, deformity rate and activity. Results: low pH and high pH test group compared with the control group, the survival rate in Cyclina sinensis embryos had no significant difference(p>0.05). D-shaped larvae that had been group and group pH9.0 distortion of rate increased significantly(P < 0.05), although embryonic development is not obvious lag, but found pH 9.0 pH 7.4 group and the group of the gastrula embryo rotational speed is slow than the control group. 2.Effect of pH on the growth of Cyclina sinensis larvaeDetermination of Cyclina sinensis Tam round larvae, D-shaped larvae, shell early, shell on the top post top, single pipe spat stage survival rate, deformity rate, shell length, activity. Test results show that D-shaped larvae stage of each experimental group survival rate had no significant difference(P > 0.05), the shell top early group pH 7.4 group and pH 9.0 survival decreased significantly, creeping period, pH 7.4 and pH 9.0 malformation group individual further deaths. The deformity rate of pH7.4 group and pH 9.0 group was significantly higher than that of control group(p<0.05) after the stage of D-shaped larva stage to the late stage of shell roof of Cyclina sinensis. There was no significant difference between the creep stage and the single water pipe period(p>0.05). No significant difference(p>0.05) between the D-shaped larval stage and the pH. The shell length of pH 7.4 group and pH 9.0 group was significantly lower than that of control group(p<0.05) at the initial stage of the shell roof to the single water pipe stage. All of the pH9.0 group died during the crawling period. 3. Effect of pH on the calcification rate of Cyclina sinensisDifferent pH environment in the calcification rate was measured during cyclina sinensis. The results showed that the calcification rate of pH7.4 group, pH8.6 group and pH9.0 group was significantly lower than that of control group(p<0.05). There was no significant difference between the pH7.8 group and the control group(p>0.05). 4. Effects of pH on Cyclina sinensis’ s SOD and CA enzyme activity.In 0h, 3h, 12 h, 1d, 2d, 3d,, 5d,7d in the visceral mass, gill, mantle of the three tissues of the SOD enzyme and CA enzyme activity change. Test results show that: 7.4 group, pH 9.0 group Cyclina sinensis whether visceral mass, mantle, gill SOD activity are within 12 h, 1d) have significant difference(P < 0.05).In the pH7.4 group, 3h, 12 h, 1d, 2d, 3d, visceral mass and gill CA activity was significantly increased(p<0.05), and the CA enzyme activity in the coat membrane was significantly increased in 12 h and 1d(p<0.05).In the pH9.0 group, the CA activity of 12 h and 1d were significantly increased(p<0.05), gill CA activity was significantly elevated(p<0.05) in 12 h, 1d and 2d. pH7.4 group and group pH 9.0 SOD enzyme and CA enzyme activity with the passage of time has a fast rise and fast process, low pH and high pH will have a greater impact on the clam SOD and CA activity.In summary, effects of different pH on Cyclina sinensis mainly in D-shaped larvae to single pipe stage and adult mollusk shell calcification, the main performance is the high rate of deformity, the survival rate decreased, slow motion and calcification rate decreases. SOD and CA activity 7 days of dynamic change, pH7.4 group and group pH9.0 SOD enzyme and CA enzyme activity with the passage of time has a fast rise and fast process, low pH and high pH will have a greater impact on Cyclina sinensis’ s SOD and CA activity. This internal body conditioning mechanism needs further research.