【作者】 李海军；

【导师】 朱松明； 叶章颖；

【作者基本信息】 浙江大学 ， 农业生物环境与能源工程， 2021， 博士

【摘要】 龟鳖作为特种水产经济动物,具有丰富的营养及药用价值。由于龟鳖在外塘养殖过程中存活率低及生长缓慢等原因,通常其在幼苗时期就被养殖在温室内,而室内一般都是无光或微光环境。如何在温室养殖模式下保证龟鳖的光照福利不仅是生产管理上的难题,亦是实现龟鳖福利化养殖需要解决的关键科学问题。论文基于温室养殖环境特点及龟鳖的生活习性设计了一套有晒台区、水域区以及饲料台的养殖系统,同时以模拟太阳光的自镇流汞灯为光源,探究了光周期对中华鳖生长性能、消化酶活性、应激反应以及肝脏抗氧化状态的影响,不同布光模式对中华鳖生长性能、应激反应、肝脏抗氧化状态以及晒背行为的影响,不同布光模式对中华草龟生长性能、血清皮质醇水平以及肝脏抗氧化状态的影响和不同光照强度对中华鳖生长、应激、免疫性能及肝脏抗氧化状态的影响。论文旨在探索光照对温室龟鳖生长及生理的影响效应,以期为温室龟鳖养殖的光照调控提供科学依据。其主要内容和结果如下:1.探究了光周期与中华鳖生长及生理的关系,实验设置了3个光周期,分别为0L:24 D、6L:18D以及12L:12D(L:Light,光照;D:Dark,黑暗),根据中华鳖的生活习性,实验系统设置了晒台区和水域区,实验过程中采用全池布光模式(晒台区及水域区均有光照),晒台区光照强度为3.25±0.02 W/m~2(320-960 nm,下同),UVB光强度为0.21-0.27 W/m~2,水域区光照强度为4.58±0.22 W/m~2,UVB光强度为0.48-0.52 W/m~2,水体温度控制在30±2℃。在进行了为期123天的养殖实验后,对其生长性能及生理状态数据进行分析。结果发现,光周期对中华鳖的生长性能无显著影响。对于存活率,光周期为0L:24D时,中华鳖的存活率为99.44%,显著高于12L:12D组。对于消化酶活性,光周期为0L:24D时,中华鳖的胰蛋白酶活性显著高于6L:18D组,脂肪酶活性显著高于12L:12D组,各组的淀粉酶活性没有显著性差异。对于应激反应,在光周期为0L:24D时,鳖血清皮质醇含量显著低于其他各组,光周期对血清乳酸含量无显著影响。对于中华鳖肝脏抗氧化酶活性,在0L:24D光周期下总抗氧化能力(T-AOC)显著低于其他各组,超氧化物歧化酶(SOD)活性显著高于其他各组,谷胱甘肽过氧化物酶(GSH-PX)活性显著低于12L:12D组。在6L:18D光周期下丙二醛(MDA)含量显著高于其他各组,随着光周期的延长,MDA呈现先上升后下降趋势。虽然光周期对中华鳖的生长性能无显著影响,但不同光周期下中华鳖的生理状态却表现出显著差异。因此,在本研究中,基于全池布光模式养殖的背景而言,较长光周期会对中华鳖的生理状态造成不利影响。2.鉴于在全池布光模式(即晒台水域布光)下,较长光周期对中华鳖的生理状态造成了不利影响。在此背景下,实验以黑暗环境(NL)为对照,探究了3种不同布光模式(晒台水域布光:LBW,仅水域布光:LW,仅晒台布光:LB)对中华鳖生长性能、生理状态及晒背行为的影响,实验中晒台区光照强度为3.25±0.02 W/m~2,UVB光强度为0.21-0.27 W/m~2,水域区光照强度为4.58±0.22 W/m~2,UVB光强度为0.48-0.52 W/m~2,实验光周期设置为12L:12D,水体温度控制在30±2℃。在进行了为期123天的养殖实验后,对其生长性能及生理状态数据进行分析。实验结果表明,布光模式对中华鳖的生长性能无显著影响。布光模式对中华鳖的存活率有显著性影响,其中LBW组中华鳖的存活率最低,显著低于NL组,但LB组、LW组及NL组之间中华鳖的存活率无显著差异。对于应激反应的影响,LB组和NL组血清皮质醇含量显著低于其他组,LB组葡萄糖水平最低,显著低于NL组和LW组,布光模式对血清乳酸水平无显著影响。对于中华鳖肝脏抗氧化状态及免疫相关指标的影响,LB组T-AOC显著低于LBW组,LB组GSH-PX活性显著低于其他各组,LB组补体3(C3)含量显著高于NL组。通过分析连续5天内不同布光模式下中华鳖的晒背行为发现,在无光环境下,温室中华鳖在摄食后4小时有进行晒背的需求。在有光环境下,光照处理组的中华鳖晒背数量均在中午12点达到峰值,但LBW组和LB组晒台上中华鳖的数量明显高于LW组。在0:00-6:00以及18:00-23:00之间的灯光关闭时段,LB组晒台上中华鳖的数量一直处于较低水平,而LBW组中华鳖的数量在此时段内处于波动起伏状态。综合中华鳖的生长性能、生理状态及晒背行为,建议中华鳖在温室养殖过程中的布光模式采取仅晒台布光(LB)。因此,对于温室中华鳖而言,仅晒台布光(LB)是适宜中华鳖生长的最佳布光模式。3.为了探究布光模式对水产动物的生长性能和生理状态影响是否具有种属特异性以及龟的最佳布光模式,实验以中华草龟为研究对象,在3种不同布光模式(晒台水域布光,LBW;仅水域布光,LW;仅晒台布光,LB)以及黑暗环境(NL)下进行了为期203天的养殖实验,实验中晒台区和水域区光照强度参数同布光模式对中华鳖的研究,实验光周期设置为12L:12D,水体温度控制在30±2℃。中华草龟在饲养203天后,对其生长性能及生理状态数据进行分析。结果表明,布光模式对中华草龟的生长性能有显著影响,在实验的第126天至实验结束,LW组草龟生长性能显著高于LBW组,但整个实验期间LW组草龟生长性能与NL组、LB组没有显著性差异。布光模式对中华草龟的存活率无显著影响。布光模式对中华草龟血清皮质醇水平有显著影响,其中LW组中华草龟血清皮质醇水平显著低于其他各组。对于草龟肝脏抗氧化酶活性的影响,LW组和LB组中华草龟肝脏过氧化氢酶(CAT)活性显著低于LBW组和NL组,LW组中华草龟肝脏MDA含量显著低于其他各组,布光模式对中华草龟肝脏T-AOC和SOD活性均无显著影响。综合布光模式对草龟生长及生理的影响,发现布光模式对龟鳖的影响具有种属特异性,对于温室养殖中华草龟而言,最佳的布光模式为仅水域布光(LW)。4.在优选的仅晒台布光模式下,探究了不同光照强度对中华鳖生长、存活、应激反应、免疫性能以及肝脏抗氧化状态的影响。实验以黑暗环境为对照组,同时设置了3组光照强度,分别是低光照强度组(光照强度为6.56±0.14 W/m~2,UVB光强度为0.58-0.62 W/m~2)、中光照强度组(光照强度为18.11±0.54 W/m~2,UVB光强度为1.15-1.23 W/m~2)和高光照强度组(光照强度为37.81±2.85 W/m~2,UVB光强度为2.27-2.55 W/m~2),实验光周期为12L:12D,水体温度控制在30±2℃。在进行了为期152天的养殖实验后,对其生长性能及生理状态数据进行分析。结果表明,低光照强度组中华鳖的生长性能显著大于高光照强度组,随着光照强度的增加,生长性能呈先上升后下降趋势。对于应激反应的影响,低光照强度组中华鳖的血清皮质醇含量显著低于高光照强度组,血清葡萄糖含量显著低于黑暗组和高光照强度组。对于中华鳖免疫性能的影响,低光照强度组溶菌酶活性显著高于其他各组,酸性磷酸酶活性显著高于黑暗组和高光照强度组,一氧化氮含量以及免疫球蛋白M含量显著高于高光照强度组。对于中华鳖肝脏抗氧化状态的影响,在低光照强度条件下,中华鳖肝脏SOD活性以及GSH-PX活性显著低于黑暗组和高光照强度组,CAT活性显著低于其他各组,GSH含量显著低于高光照强度组,MDA含量显著低于黑暗组和高光照强度组。因此,综合中华鳖的生长性能、应激反应、肝脏抗氧化应激和免疫性能,建议在仅晒台布光模式下提供低强度的光照。更多还原

【Abstract】 Turtles are special aquatic economic animals,which are deeply loved by people because of rich nutrition and medicinal value.Due to the low survival rate and slow growth of the turtles when cultured outdoors,they are usually reared in the greenhouse during the seedling period.However,the indoor environment is generally dark or low light.How to ensure the welfare of turtles when cultured in the greenhouse is not only a difficult problem in production management,but also a key scientific problem that needs to be solved to realize the welfare of turtles.In this study,a breeding system is designed based on the characteristics of the greenhouse environment and the living habits of turtles.At the same time,the simulated solar lamp(self-ballasted mercury vapor lamp)is used as the light source to explore the influence of photoperiod on the growth performance,digestive enzyme activity,stress response and liver antioxidant status of the Chinese soft-shelled turtle,the influence of different lighting modes on the growth performance,stress response,liver antioxidant status and basking behavior of the Chinese soft-shelled turtle,the influence of lighting modes on the growth performance,serum cortisol level and liver antioxidant status of juvenile Chinese three-keeled pond turtle cultured in greenhouse and the influence of light intensity on the growth,stress,immune performance and liver antioxidant status of the Chinese soft-shelled turtle.The purpose of this thesis is to explore the effects of light on the growth,behavior and physiology of turtles cultured in greenhouse,in order to provide a scientific basis for the regulation of light in the greenhouse.The main content and conclusions of this study are listed as follows:1.In order to explore the relationship between the photoperiod and the growth and physiology of the Chinese soft-shelled turtle,turtles were reared under three photoperiods,0L:24 D,6L:18D and 12L:12D(L:Light,D:Dark).According to the living habits of the Chinese soft-shelled turtle,the experimental system has set up a basking area and a water area.During the experiment,the mode of lighting the full tank is adopted.Therefore,both the basking area and the water area have light.The light intensity of the basking area is 3.25±0.02 W/m~2(320-960 nm,the same below)and UVB light intensity is0.21-0.27 W/m~2.The light intensity of the water area is 4.58±0.22 W/m~2and UVB light intensity is 0.48-0.52 W/m~2.Water temperature is controlled at 30±2℃.After the Chinese soft-shelled turtle was reared in the system for 123 days,its growth performance and physiological state data were analyzed.Results showed that differences in growth were insignificant during the experiment.When the photoperiod is 0L:24D,the survival rate of Chinese soft-shelled turtle is 99.44%,which is significantly higher than that of the 12L:12D group.When the photoperiod was 0L:24D,the trypsin activity of soft-shelled turtle was significantly higher than that of the 6L:18D group,and the lipase activity was significantly higher than that of the 12L:12D group,but there was no significant difference in amylase activity between the groups.In the 0L:24D photoperiod,the serum cortisol content was significantly lower than the other groups,but the photoperiod had no significant effect on the serum lactic acid content.For the antioxidant enzyme activity of the Chinese soft-shelled turtle liver,under the 0L:24D photoperiod,the T-AOC was significantly lower than the other groups,the SOD activity was significantly higher than the other groups,and the GSH-PX activity was significantly lower than the 12L:12D group.The content of MDA under 6L:18D photoperiod was significantly higher than that of other groups.With the extension of photoperiod,MDA showed a trend of first rising and then falling.Although the photoperiod had no significant effect on the growth performance of Chinese soft-shelled turtle,the physiological state of Chinese soft-shelled turtle under different photoperiods showed significant differences.Therefore,in this study,based on the background of lighting the full tank,a longer photoperiod will adversely affect the physiological status of the Chinese soft-shelled turtle.2.In view of the mode of lighting the full tank,a longer photoperiod has an adverse effect on the physiological state of the Chinese soft-shelled turtle.In this context,a dark environment(NL)and three different lighting modes(lighting the basking area and water area simultaneously,LBW;light the water area only,LW;light the basking area only,LB)were set to explore the effects on the growth performance,physiological status and basking behavior of the Chinese soft-shelled turtle.In the experiment,the light intensity of the basking area is 3.25±0.02 W/m~2and UVB light intensity is 0.21-0.27 W/m~2.The light intensity of the water area is 4.58±0.22 W/m~2and UVB light intensity is 0.48-0.52W/m~2.Water temperature is controlled at 30±2℃.After 123 days of rearing,the growth performance and physiological status of the Chinese soft-shelled turtle were analyzed.Results showed that there were no significant effects on the growth performance of the Chinese soft-shelled turtles.The lighting mode has a significant impact on the survival rate of Chinese soft-shelled turtle.Among them,the survival rate of Chinese soft-shelled turtle is the lowest in LBW group,which is significantly lower than that of NL group.There were no significant differences in survival rate of Chinese soft-shelled turtle between LB group,LW group and NL group.Regarding the stress response,the serum cortisol content of LB group and NL group was significantly lower than other groups,and the glucose level of LB group was the lowest,which was significantly lower than that of NL group and LW group.The lighting mode had no significant effects on serum lactic acid level.Regarding the liver antioxidant status and immune-related indicators of the Chinese soft-shelled turtle,the T-AOC in LB was significantly lower than that in LBW,the GSH-PX activity in LB was significantly lower than that in the other groups,and the C3 content of the LB group was significantly higher than that of the NL group.Therefore,for Chinese soft-shelled turtles in the greenhouse,lighting the basking area only(LB)is the best lighting modes for the growth and health of Chinese soft-shelled turtles.By analyzing the basking behavior of the Chinese soft-shelled turtle under different lighting modes for 5 consecutive days,it was found that in the dark environment,the Chinese soft-shelled turtle in greenhouse needed to have the basking 4 hours after eating.In the light environment,the number of Chinese soft-shelled turtles in the group with light reached their peak at 12:00,but the number of Chinese soft-shelled turtles on the basking area in LBW and LB was significantly higher than that in LW.During the light off time period between 0:00-6:00 and 18:00-23:00,the number of Chinese soft-shelled turtles in LB was at a low level,while the number of Chinese soft-shelled turtles in LBW is fluctuating during this period.Based on the basking behavior of the Chinese soft-shelled turtle,it is recommended that lighting the basking area only(LB)is the optical lighting mode for the Chinese soft-shelled turtle in a greenhouse.3.In order to explore whether the influences of different lighting modes on growth performance and physiological status of aquatic animals were species-specific and the best lighting modes for juvenile Chinese three-keeled pond turtle cultured in greenhouse,the turtles were reared in a dark environment(control group,NL)and three different lighting modes(lighting the basking area and water area simultaneously,LBW;lighting the water area only,LW;lighting the basking area only,LB)for 203 days.In the experiment,the light intensity of the basking area and the water area is as same as the parameter of the study on lighting mode of Chinese soft-shelled turtle.Water temperature is controlled at 30±2℃.After the Chinese three-keeled pond turtle was raised for 203days,its growth performance and physiological status data were analyzed.The results showed that no significant differences were observed in weight gain rate in the first 92days of the experiment,while on the 126th days of the experiment,the weight gain rate of the turtle exposed to LW was significantly higher than that exposed to LBW.At the end of the experiment(203 days),the turtle in the LW group exhibited higher weight gain and specific growth rate compared to other treatments.For survival rate,there were no significant differences among the treatments.With regard to cortisol level,there were significant differences among the treatments,and the cortisol level in turtle exposed to LW was significantly lower than that in other treatments.Regarding the oxidative stress,the level of catalase(CAT)in turtle exposed to LW and LB was significantly lower than that exposed to LBW and NL.The malonaldehyde(MDA)activity in turtle exposed to LW was significantly lower compared to other treatments.Synthesizing the effects of lighting modes on the growth and physiology of turtle,it was found that the effects of lighting modes on turtles were species-specific.For Chinese three-keeled pond turtle cultured in a greenhouse,the optimal lighting mode was lighting the water area only.4.In this study,the effects of different light intensities on the growth performance and physiological status of the Chinese soft-shelled turtle were explored with the preferred mode of lighting the basking area only.In the experiment,a dark environment was used as the control group,and three kinds of light intensities were set at the same time,namely the low light intensity group(light intensity:6.56±0.14 W/m~2;UVB light intensity:0.58-0.62 W/m~2),medium light intensity group(light intensity:18.11±0.54W/m2;UVB light intensity:1.15-1.23 W/m~2)and high light intensity group(light intensity:37.81±2.85 W/m~2;UVB light intensity:2.27-2.55 W/m~2).The experimental photoperiod was 12L:12D,and the water temperature was controlled at 30±2°C.After cultivating in the greenhouse for 152 days,it was found that the growth performance of the Chinese soft-shelled turtle in the low light intensity group was significantly higher than that in the high light intensity group.With the increase of the light intensity,the growth performance presented earlier increase and later decrease trend.Regarding the stress response,the serum cortisol level of turtles in the low light intensity group was significantly lower than that in the high light intensity group,and the serum glucose level was significantly lower than that in the dark group and high light intensity group.Regarding the immune performance,in the low light intensity group,the activity of LZM was significantly higher than that in the other groups,the activity of ACP was significantly higher than that in the dark group and high light intensity group,the contents of NO and Ig M were significantly higher than that in the high light intensity group.Regarding the anti-oxidative stress in the liver of soft-shelled turtle,under the condition of low light intensity,SOD activity and GSH-PX activity in the liver of soft-shelled turtle were significantly lower than that in the dark group and high light intensity group.And the CAT activity of turtles in the low light intensity group was the lowest among the treatments.The GSH content was significantly lower in the low light intensity group than that in the high light intensity group.The MDA content was significantly lower in the low light intensity group than that in the dark group and high light intensity group.Therefore,considering the growth performance,stress response,liver anti-oxidative stress and immune performance of the Chinese soft-shelled turtle,it was recommended to provide a lower intensity of light when lighting the basking area only.更多还原