摘要
将体质量(10±2)g的中华绒螯蟹(Eriocheir sinensis)幼蟹饲养在φ=15 cm、h=24 cm盒中,内添加(510±1)g池塘底泥。按清塘的常规剂量,盒中分别添加清塘威(30%茶皂素+0.5%烟碱+增效剂,A组)、清塘净(氰戊菊酯20 g/mL,B组)和甲氰菊酯(20%甲氰菊酯,C组)各组分别1.5 mL,再加水稀释至1 500 mL。浸泡1周倒去残液,再在每个饲养盒中加入1 500 m L曝气自来水(模拟清塘消毒)。22℃~25℃时每个饲养盒中投放1只蟹种,每组12个饲养盒。每天根据河蟹实际残饵情况投喂饵料,每周换水一次,观察河蟹的生长,50 d后统计存活数(N)及增重(WT)。在野外用三种清塘剂清塘后,定期补水以使水位保持在1.0~1.5 m下饲养河蟹50 d后,在500 mL广口瓶中加水封闭,记录个体死亡所经历时间和河蟹的窒息临界点。将A、B、C组的三种清塘剂100 g底泥放置于水迷宫(长100 cm、宽10 cm)的两端选择区的一端,另一端为D组100 g底泥,清塘剂处理的底泥分为早期(试验初期新配)和后期(50 d饲养后)的底泥,每组取自无清塘剂的池塘河蟹30只,以A组为例,让河蟹在水迷宫中作出前期A-D、后期A-D的选择,B、C组同理。观察时长为15 min,记录试验蟹的首次选择结果及犹豫期时长(t),探究不同清塘剂对河蟹生长、增重、耐缺氧能力和趋避行为的影响。结果表明,各组间河蟹的成活率无显著差异(P>0.05),但含清塘剂组河蟹的绝对增重显著低于对照组(P<0.05),而试验组之间的差异不显著(P>0.05);A、B、C组的河蟹绝对增重量变异系数分别为94.91%、43.64%和34.55%,表明后两者清塘剂对河蟹生长的抑制具普遍性。试验组的窒息临界点溶氧值和所经历时间与空白组显著不同(P<0.05),表明清塘剂显著抑制了河蟹耐缺氧能力。趋避结果表明,河蟹对早期的三组清塘剂底泥均具显著回避性,对饲养河蟹50 d后的清塘威底泥回避性不显著(P>0.05)。各组后期表现出犹豫行为(ambivalent behavior)的个数均显著大于前期,表明各清塘剂毒性随时间下降,其中清塘威毒性下降最明显。本试验结果表明:清塘威对河蟹各项指标影响最小,但出于环保与健康化养殖的角度建议慎用农药类清塘剂。
Juvenile Chinese mitten handed crab(Eriocheir sinensis)with body weight of(10±2)g was reared in a box with φ=15 cm and h=24 cm, and addition of(510±1)g pond bottom mud. Three types of disinfectants Qingtangwei(30% tea saponin + 0.5% nicotine + synergist, group A), Qingtangjing(fenvalerate 20 g/mL, group B)and Qingtangwei(30% tea saponin + 0.5% nicotine + synergist, group A), and Qingtangjing(fenvalerate 20 g/mL, group B)and fenpropathrin(20% fenpropathrin, group C)of each 1.5 mL were added to the box, respectively, then added into the water to dilute to 1 500 mL in the boxes and immersed for 1 week to pour out the remaining liquid, and then added 1 500 mL aerated tap water to each breeding box(simulating clear pond disinfection). The juvenile Chinese mitten handed crab were stocked into the boxes containing 1 500 mL aerated tapwater and fed at stocking rate of one crab per box at water temperature of 22℃ ~ 25℃, and 12 breeding boxes in each group for 50 days to observe the survival(N)and weight gain. The juvenile Chinese mitten handed crab reared in the ponds administrated with the three kinds of disinfectants and kept at a water level of 1.0~1.5 m via water filling for 50 days in the field was placed in 500 mL jars, filled with water and covered with 2 cm of liquid paraffin oil until the mouth of the crab was closed. The time elapsed for the confirmed death of the individual(hypoxia tolerance time)was recorded, and the dissolved oxygen value of the water sample was the critical point of suffocation of the crab. The 100 g pond bottom mud of the three disinfectants in groups A, B and C, divided into early stage(newly prepared at the beginning of the experiment)and late stage(after 50 days of rearing), was placed at one end of the selection zone at both ends of the water labyrinth(length 100 cm, width 10 cm), and the other end was the 100 g bottom mud in group D, the bottom treated by the disinfectants. Thirty samples of Chinese mitten handed crab collected from ponds without the disinfectants were observed early AD in the water labyrinth to the selection of AD in the later stage for 15 min. The observation time and the first selection results of the test crab and the hesitation period(t)were recorded to explore the effects of different disinfectants on growth, weight gain, hypoxia tolerance and avoidance behavior of Chinese mitten handed crab. The results showed that there was significantly lower absolute weight gain in the crab in the experimental groups containing disinfectants than that in the blank control group(P < 0.05), without significant difference in the survival rate and absolute weight gain of the crab among the groups, and with the coefficient of variation of absolute weight gain of 94.91% in group A, 43.64% in group B, and 34.55% in group C, indicating that the latter two disinfectants had universal inhibition of the growth of the crab populations. The dissolved oxygen value and the elapsed time at the critical point of asphyxiation in the test group were significantly different from that in the blank group(P < 0.05), indicating that the disinfectants had a significant inhibitory effect on the hypoxic tolerance of the crab. The avoidance tests showed that crab were significantly repellent to early in the three groups of disinfectants sediments, but not significantly repellent to the pond sediments without any disinfectants after 50 days of crabraising, from the later stages in each group, they showed ambivalent behavior. The numbers were significantly more than those in the previous period, indicating that the toxicity of the disinfectants was decreased over time, and the disinfectants Qingtangwei had the most decrease in toxicity. The findings indicated that Qingtangwei has the least impact on various indicators of crab, but from the perspective of environmental protection and healthy farming, it is recommended to use pesticide-based disinfectants with caution.
作者
郭晏汝
丁丽花
葛家春
张曹旸
刘茂松
GUO Yanru;DING Lihua;GE Jiachun;ZHANG Caoyang;LIU Maosong(College of Life Sciences,Nanjing University,Nanjing 210023,China;China Urban Planning and Design Institute,Qingdao 266071,China;Jiangsu Institute of Freshwater Fisheries,Nanjing 210017,China;Changzhou Senior High School of Jiangsu Province,Changzhou 213003,China)
出处
《水产学杂志》
CAS
北大核心
2023年第1期65-71,共7页
Chinese Journal of Fisheries
基金
国家自然科学基金委项目(NSFCJ1103512)
江苏省现代农业重点项目(BE2019393)。
关键词
河蟹
清塘剂
生长
窒息
趋避行为
Eriocheir sinensis
pesticide disinfectant
growth
suffocation
avoidance behavior
作者简介
郭晏汝(1997-),女,硕士研究生,研究方向为植物学.E-mail:MG1930005@smail.nju.edu.cn;通信作者:刘茂松(1965-),男,副教授,从事生态学研究.E-mail:msliu@nju.edu.cn。
