葡萄糖和维生素C对镇海林蛙蝌蚪生长及其三种酶活性的影响

营养源对动物生长发育具有重要作用。本文采用静水实验浸泡法探究葡萄糖和维生素C对镇海林蛙(Rana zhenhaiensis)蝌蚪生长及其苹果酸脱氢酶、乳酸脱氢酶及淀粉酶活性的影响。在葡萄糖实验组共分为0.5、1.0和2.0 g/L三个浓度组,维生素C实验组共分为10.0、20.0和30.0 mg/L浓度组,另设1组加曝气水作为对照组。在葡萄糖实验组中,蝌蚪存活率在不同实验组间的差异不显著(P>0.05)。变态时间在0.5 g/L和1.0 g/L实验组最短,分别为(43.0±4.0)d和(43.0±3.4)d,2.0 g/L实验组最长,为(46.2±5.4)d,且实验组间差异显著(P <0.05)。变态时,0.5 g/L实验组的体重和体全长最大,且各实验组间的体重差异显著(P <0.01),但体全长差异不显著(P> 0.05)。增重率在0.5 g/L实验组最高,为(9.67±1.71)mg/d,对照组最低,为(7.54±1.22)mg/d,且各实验组之间差异显著(P<0.05)。维生素C实验组中,存活率在各实验组间差异不显著(P> 0.05)。所有实验...

Effects of Glucose and Vitamin C on Growth and Activities of Three Enzymes of Rana zhenhaiensis Tadpoles

The nutrition source plays an important role in the growth and development of animals. In this study, the effects of glucose and vitamin C (Vc) on the growth and activity of three enzymes (malate dehydrogenase: MDH, lactate dehydrogenase: LDH, amylase: AMS) of tadpoles of Rana zhenhaiensis were studied using the static water immersion method. Healthy and uniform-size sibling tadpoles of R. zhenhaiensis with developmental stages of Gosner 29 and 30 were selected for testing. For glucose treatment, three experimental concentrations were chosen: 0.5, 1.0 and 2.0 g/L, respectively; and for Vc treatment, three experimental concentration were chosen: 10.0, 20.0 and 30.0 mg/L, respectively. Treatment with dechlorinated tap water was set up for control. Each treatment was replicated three times, with 10 objective tadpoles. The experimental period was lasted for tadpole metamorphosis until forelimb emerged (Gosner 42). The results showed that survival rates among different glucose treatments were not significantly different (P > 0.05). Metamorphic time (P > 0.05) was significantly different among treatments, with the shortest period in the 0.5 g/L (43.0 ± 4.0 d) and 1.0 g/L (43.0 ± 3.4 d) group, and the longest period in the 2.0 g/L (46.2 ± 5.4 d) treatment. Both body mass and total body length of metamorphosis were found to be the largest in the 0.5 g/L treatment group. Body mass (P < 0.01) of metamorphosis among different treatments was significantly different, but total body length (P > 0.05) was not significantly different. Rate of weight growth was found to be the highest in the 0.5 g/L treatment (9.67 ± 1.71 mg/d) and the lowest in the control group (7.54 ± 1.22 mg/d), and the differences were significant (P < 0.05) (Fig. 2). For Vc treatments, like those in the glucose experimental treatments, survival rates among different treatments were not significantly different (P > 0.05). Developmental stage of each treatment was more advanced than that of the control when examined 1 week later, as well as on day 14, 21 and 28, respectively. Metamorphic time (all treatments were similar to 43.0 d, P > 0.05) was not significantly different among all treatments. Total body length and body mass of metamorphosis in control treatment were smaller than those of 20.0 mg/L and 30.0 mg/L treatment groups, but total body length (P > 0.05) and body mass (P > 0.05) was not significantly different among the treatments during the experimental period. Rate of weight growth was found to be the highest in both 20.0 mg/L and 30.0 mg/L treatments and the lowest in the 10.0 mg/L treatment, but there was no significant difference (P > 0.05) (Fig. 3). Both glucose and Vc could impact enzyme activity of R. zhenhaiensis tadpoles. The activity of MDH increased with the increase of experimental concentrations of glucose and Vc. The activities of LDH and AMS were highest in 1.0 g/L of glucose group and 10.0 mg/L of Vc group, respectively (Table 1). These findings suggest that 10.0 mg/L of Vc or 1.0 g/L of glucose should be the optimum exogenous concentrations that could promote the growth performance and enzymatic activity of R. zhenhaiensis tadpoles. These data might provide some valuable information for R. zhenhaiensis breeding in the future.