菲律宾蛤仔3种壳色群体低盐耐受能力的比较研究

摘要

The mortality rate,average body weight increment,the osmotic pressure,ATPase activity,total haemocyte count (THC),and sodium ion concentration,chloride ion concentration,and plasma protein concentration of haemolymph were monitored in Manila clam Ruditapes philippinarum with different shell colors exposed to low salinity of 15 for 0,1.5,3,6,12,24 and 48 h to evaluate the toleration of the clam with different shell colors to low salinity stress.The results showed the minimal mortality (3.92％)was observed in the zebra color clam which had significantly higher haemolymph osmotic pressure than in the control group at 24 h (P＜0.05),all the three groups showing approximate haemolymph osmotic pressure to seawater at 48 h.The increasing haemolymph sodium concentrations was found in the three shell color groups,the peak level in the zebra group and pearl-white group clam,and significantly higher than in the control group at 24 h (P＜0.05).There were increase first in chloride ion concentration in the control group clams,but the zebra group and pearl-white group clam showed a trend of initial decrease in chloride ion concentration in the zebra color group and pearl-white color group,even though significantly higher than in the control group at 24 h(P＜0.05).The ATPase activity all had an increase process in gills of the three shell color groups,pearl-white clam showing significantly higher than the clam in the control group did at 6 h and 24 h (P＜0.05).The total hemocyte count(THC) was also fluctuated in the experiment,and the zebra group and pearl-white group clams had significantly lower THC than the clams in the control group (P＜0.05),but the zebra group had significantly higher than the clam in the control did at 48 h (P＜0.05).%通过测定3种壳色群体菲律宾蛤仔Ruditapesp hilippenarum(斑马蛤、珍珠白和对照组)在低盐度(15)海水中0、1.5、3、6、12、24、48 h时的死亡率、个体平均增重、血浆渗透压、Na+浓度、Cl-浓度、血浆总蛋白浓度、鳃组织三磷酸腺苷(ATP)酶活性及血细胞总数等指标,比较了3种壳色菲律宾蛤仔的低盐耐受能力.结果表明:斑马蛤的死亡率最低(3.92％)；3种壳色蛤仔的血浆渗透压均呈现逐渐降低的趋势,第24h时,斑马蛤渗透压显著高于对照组(P＜0.05),第48 h时,3种壳色蛤仔的血浆渗透压都与海水渗透压接近；3种壳色蛤仔血淋巴中Na+浓度均呈现升高过程,第24h时,珍珠白和斑马蛤的Na+浓度达到最大值,显著高于对照组(P＜0.05)；对照组蛤仔Cl-浓度呈现先升高后恢复的过程,而斑马蛤和珍珠白Cl-浓度呈现先降低后恢复的过程,第24h时,斑马蛤和珍珠白血淋巴Cl-浓度显著高于对照组(P＜0.05)；3种壳色蛤仔的ATP酶活性呈现先升高后恢复的过程,第6h和24 h时,珍珠白鳃组织ATP酶活性显著高于对照组(P＜0.05)；3种壳色蛤仔的血细胞总数也呈现先升高后恢复的过程,第1.5h时,珍珠白和斑马蛤血细胞总数显著低于对照组(P＜0.05),第48 h时,斑马蛤血细胞总数显著高于对照组(P＜0.05).