不同饵料和水温对口虾蛄成活、生长及育肥性能的影响

Effects of Different Diets and Water Temperatures on Survival, Growth, Fattening Performance of Oratosquilla oratoria

为比较不同饵料、水温对口虾蛄(Oratosquilla oratoria)在越冬期间生长育肥及性腺发育的影响,选用当年池塘养殖口虾蛄[初始体重(21.99±4.86)g,n=600]为研究对象,在养殖设施相同条件下,研究了在自然水温(7.7～13.6℃)和加温(17.1～20.9℃)条件下投喂去壳蛤蜊(Ruditapes philippinarum)和冰鲜杂鱼对口虾蛄的成活率、体长、体宽、体重、性腺指数、肌肉指数及可食率等7项指标的影响。实验共分常温蛤蜊、常温冰鲜杂鱼、加温蛤蜊和加温冰鲜杂鱼4个实验组,实验周期为90 d。结果显示:(1)加温可使口虾蛄成活率显著降低,温度是影响口虾蛄越冬成活的重要因素之一;(2)在整个实验过程中口虾蛄的体长、体宽和体重3项生物学指标均随实验天数的增加呈增长趋势,但各指标不同时间均不存在显著性差异(P> 0.05);(3)常温条件比加温条件更有益于口虾蛄性腺指数的增加,其中以常温投喂去壳蛤蜊的效果最好,其性腺指数平均可达14.53%(♀)和7.69%(♂);(4)在整个实验过程中,口虾蛄的肌肉指数随实验进行总体呈上升趋势,除常温蛤蜊与加温蛤蜊实验组间的口虾蛄可食率存在显著性差异(P <0.05)外,其他各实验组两两之间均不存在显著性差异(P>0.05);(5)不同饵料和水温的交互影响结果表明,温度是影响口虾蛄性腺指数的重要因素(P <0.01),饵料仅对雌性口虾蛄性腺指数产生显著性影响(P <0.01)。实验结果表明,相对于加温环境,常温环境基本能满足口虾蛄越冬期间的生长和育肥的需求,特别是在10～13℃的水温条件;与冰鲜杂鱼相比,摄食去壳蛤蜊更有利于口虾蛄的性腺发育积累。

Oratosquilla oratoria is a common economic marine crustacean in China, which is known for its umami taste and high nutritional value. Due to offshore environment destruction and overfishing, the capture production of O. oratoria no longer meet the market demand, making it urgently important to pay closer attention to artificial culture. However, the pond culture of O. oratoria always showed defects in growth rate and gonadal development, and thus promoting its gonadal development had become a key technical problem in artificial culture. To solve this problem, this study investigated effects of different diet and water temperature on the survival and growth of O. oratoria during the overwintering period. In total 600 individuals(initial body weight: 21.99 ± 4.86 g) were used for this study, and sixteen samples(8 males and 8 females) were randomly selected and anatomized for each group on the day 0 th, 45 th, 90 th to explore the influences of two kind foods(content of clam and frozen fresh fish) under two different temperature named natural(7.7 ℃ to 13.6 ℃) and heated(17.1 ℃ to 20.9 ℃) on the survival rate, body length, body width,body weight, gonad index, muscle index, and total edible rate. Results showed that:(1) The survival rate of the water heated group significantly decreased compared to that of natural temperature group(P < 0.05),which implied water temperature was one of the most important factors that influenced the survival rate during the overwintering period;(2) The body length, body width, body weight and other biological indices of O. oratoria kept an increasing trend throughout the whole process, without any significant difference found between any each groups(P > 0.05), and the best feeding pattern on growth effects was group of frozen fresh fish at natural temperature, while the worst was group of clam at natural temperature;(3) the gonad development condition under natural water temperature was better than that under heating water temperature in winter, and the optimal gonad development condition was achieved in group of clams at natural water temperature, with the gonad index 14.53% for females and 7.69% for males;(4) The muscle index showed an increasing tendency during the whole process with the highest muscle index(31.75%) detected in group of frozen fresh fish at natural temperature. For the edible rate, the only finding of significant difference was between the groups of clams at natural temperature and at heating temperature, respectively(P < 0.05). The highest edible rate(39.96%) was achieved in group of clams at natural temperature, while the lowest(36.08%)was found in group of clams at heating temperature.(5) The interaction results of different diets and water temperatures showed that diets had significant effects on ovary index(P < 0.01). In general, natural water temperature, especially ranging from 10℃ to 13 ℃, could meet the basic requirements for the growth and fattening performance of O. oratoria in winter. Compared to frozen fresh fish, clam was more beneficial for the substance accumulation in gonad of O. oratoria.