2015年4月6日—10月26日,在桑沟湾海区现场研究了牡蛎壳粉缓释剂(Careshell)对魁蚶(Scapharca broughtonii)生长和存活的影响。按照缓释剂的重量比设置4个处理组,其中,魁蚶的初始体重均为160 g/组,缓释剂的重量分别为0(对照组C0)、80 g(C1组)、160 g(C2组)和320 g(C3组)。实验共进行200 d,每40 d测量各实验组魁蚶的生长参数(壳长、壳宽、壳高、湿重),计录死亡个体数,计算不同阶段(40 d间隔)魁蚶的特定生长率(SGR)及死亡率。结果显示,C3组魁蚶各生长参数显著高于C0组(P〈0.05),但与C1、C2组差异不显著(P〉0.05)。经过200 d的养殖实验,C3组壳长、壳宽、壳高和湿重的特定生长率分别为(0.34±0.01)%/d、(0.46±0.02)%/d、(0.39±0.01)%/d、(1.11±0.002)%/d,均极显著高于C0组(P〈0.01),平均增加了17.9%、20.3%、18.1%、16.7%。C3组死亡率为(19.6±5.6)%,低于C0组的(26.1±2.5)%,但差异不显著(P〉0.05)。
The effect of careshell on growth and survival of Scapharca broughtonii was investigated in Sanggou Bay from April 6 to October 26,2015. S. broughtonii with initial mean weight of 160 g were exposed to the environment with four doses of Careshell: 0 (control, C0), 80 g(C1), 160 g(C2) and 320 g(C3) respectively. The growth indices (shell length, shell width, shell height, wet weight) of S. broughtonii were measured and the number of deaths recorded in every 40-day period. The experiment lasted 200 days. Growth and mortality rates were calculated in each period. The results showed that the growth indices of S. broughtonii for C3 group were significantly higher than those of the control group C0 (P〈0.05), but the difference with C2 and C1 was not significant (P〉0.05). The growth rates of shell length, shell width, shell height and wet weight for C3 during the experimental period were, (0.34±0.01)%/d, (0.46±0.02)%/d, (0.39±0.01)%/d and (1.11±0.002)%/d, respectively, which were significantly higher than those of C0 (P〈0.01). On the average, the indices during the experimental period were increased by 17.9%, 20.3%, 18.1% and 16.7% respectively, which were significantly higher than those of C0 (P〈0.01). The mortality rate of C3 group (19.6±5.6)% was lower than that of the control group C0 (26.1±2.5)%, but the difference was not significant (P〉0.05)