【作者】 何金星；

【导师】 黄成；

【作者基本信息】 南京大学 ， 动物学， 2010， 硕士

【摘要】 本文以克氏原螯虾(Procambarus clarkii)为材料,分别研究了营养性饥饿限制和完全性饥饿限制下螯虾生长,生理指标的变化；长周期饥饿复投喂和不同周期性饥饿复投喂下螯虾的补偿生长变化与机理。实验共分如下三个阶段：1.分别以动物蛋白：淀粉：纤维素为1：1：0、1：0：1、0：1：1、1：1：1的四种混合饲料喂养克氏原螯虾44d,并于10个时间点测定螯虾三种肠胃消化酶、S0D、糖原,结果显示：(1)饲料营养组分对螯虾肠胃相应消化酶有良好的诱导作用：动物蛋白和纤维素均在0,33,50%三梯度上引起相应消化酶的适应性上升,而淀粉仅在0,33%两梯度上引起淀粉酶上升,说明螯虾对淀粉消化能力有限,此外各营养组分对非对应消化酶也有影响作用；(2)较高的动物蛋白和纤维素均有益于SOD提高,而高淀粉则会显著降低螯虾SOD值；(3)肝糖原在高蛋白情况下能不受饲料中碳水化合物下降的影响,肌糖原则表观上和饲料中糖含量保持一致。(4)各生化指标均在实验开始后的一定天数波动后保持稳定。表明：克氏原螯虾对饲料组分的变化具有一定的适应性。但就螯虾生理状态而言,动物蛋白和纤维素的营养意义大于淀粉。2.以持续投喂96天雄性克氏原螯虾为对照组(C),对饥饿1,2,4,8,12,16,24,32d(S1-S32)雄性克氏原螯虾复投喂至96d,于实验中不同时间点检测螯虾体重变化,特殊增长率(SGR),肝体比(HSI), SOD,肠胃蛋白酶及恢复喂食期间的食物转化率(FCE),摄食率(FR),实验结束时统计死亡个数。实验表明：(1)饥饿4d内S0D显著上升高于对照水平,饥饿时间进一步增加则显著下降至低于对照组水平,其他指标则均随饥饿时间的延长,显著下降,饥饿至16d后均逐渐保持平稳；(2)在经历不同饥饿时间后,螯虾体重与对照组的差异逐渐增大,各实验组复投喂时快速生长能力也各不相同,这直接影响各组补偿生长程度；实验结束时,螯虾饥饿1-4d(S1,S2,S4)出现了完全补偿生长,饥饿8-12d(S8,S12)出现了超额补偿生长,其中S8平均体重高于S12,饥饿16d-24d(S16,S24)出现了部分补偿生长,饥饿32d(S32)出现了不补偿生长；(3)图形拟合显示：螯虾食物转化率,摄食率均与特殊生长率呈显著正相关关系,表明：螯虾的补偿生长是通过提高摄食率和食物转化率共同作用造成；(4)恢复喂食时S1-S24的蛋白酶均显著上升,其中S1-S16组均可上升至高于对照水平,96d时均与对照无差异,S24,S32组96d时仍显著低于对照,S32仅比饥饿结束时上升31.62%；HSI和蛋白酶活力之间存在显著的正相关线性关系,恢复喂食后,螯虾的HSI开始上升,实验结束时,S1-12组均与对照无显著差异,S16和S24则略低于对照组,S32组则仅比恢复喂食开始前上升了8.62%,这表明：复投喂中蛋白酶活性的上升和复投喂初期较低的代谢水平导致了螯虾食物转化率的提高；而在快速增长后期,较高的代谢水平则促进了已积累的能量快速利用。(5)复投喂期间,S1-S16组SOD在一段时间后均能恢复至对照组水平,S24,S 32组则一直显著低于对照水平,实验结束时,S1-S4组螯虾死亡率与对照无显著差异,其余实验组随饥饿时间的增加,死亡率显著上升,最终死亡率和SOD的累计变化是一致的。3.以持续投喂(SR00)为对照组,周期性饥饿天数1、2、4、6、8、12、18d后等同时间复投喂(SR11-SR1818)为实验组,饲养克氏原螯虾72d。于不同时间点测量得螯虾单体重量(W),计算其特殊生长率,该结果表明：实验结束时,饥饿周期1d的螯虾出现完全补偿生长,2-6d螯虾出现超额补偿生长,8-18d螯虾出现部分补偿生长；且同组螯虾在不同时间点均表现出相同的补偿生长程度。于72d测量得螯虾的SOD (S),存活率,肝糖原(G1),肌糖原(Gm),肠胃淀粉(Es),肠胃蛋白酶(Ep),含肉率(R),肝体比(H)等生理指标,结果显示：螯虾SOD随饥饿周期时间增加显著性下降,存活率在SR66-SR1818组间无显著差异,饥饿周期0-4d内,螯虾SOD和存活率与对照组无显著性差异,但饥饿周期时间进一步增加后,均显著低于对照。糖原,肝体比,肠胃道消化酶的变化与螯虾体重改变有较明显的一致性,含肉率则变化较小。说明消化酶及糖原积累均对螯虾补偿生长有直接影响。建立W, S, G1, Gm, Es, Ep, H与t的拟合方程,参数分析结果表明：当t为3-4d时螯虾补偿生长状况最佳,适于在生产养殖中应用,而当t≥15d时,螯虾可能出现一系列不可逆转的损伤。综上所述：营养限制性饥饿和完全限制性饥饿均会显著影响螯虾的生长生理指标。但对克氏原螯虾不同生理指标的影响则并不一致。长周期和多重周期下补偿生长则显示了相同的机理。更多还原

【Abstract】 Three experiments were carried out as follow to determine compensatory growth of red swamp crayfish Procambarus clarkii with single long-term and cycling feeding regimes. The effect of nutrition-restricted starvation and feed deprivation are also covered. 1. Crayfish were fed with four mixed diets containing different levels of protein, starch, cellulose:A(50/50/0), B(50/0/50), C(0/50/50), D(33/33/33), respectively, to investigate their digestive enzyme, SOD, glycogen at different period of time (0/2/4/6/8/12/16/24/32/44d). The result showed that nutrient components could induce corresponding gastrointestinal digestive enzymes of crayfish at dietary protein or cellulose level of 0,33,50%, comparing to starch 0,33%; they had influences on other digestive enzymes as well. Animal protein and cellulose at high level were beneficial for the SOD, while starch was opposite. Liver glycogen of crayfish fed with high-protein diets were even higher than these with high- Carbohydrate diets, meanwhile, the muscle glycogen apparent consistent with the content of Carbohydrate. Overall, Crayfish was well adaptable to changes in the dietary composition. All biochemical indicators reach stables after days of Fluctuations. However, animal protein and cellulose are much more important than starch for crayfish.2 Groups of male crayfish were exposed for 96 days to nine different regimes:control (fed every day); 1,2,4,8,12,16,24,32 days of fasting followed by refeeding (designated S1-S12, respectively). Mean weight, Special Growth Rate(SGR), Hepatosomatic Index(HIS), SOD, pepsin, Feed Conversion Efficiency(FCE) and Feeding rate(FR) were measured at different time points, and the number of deaths was counted after the experiment. Results:(1) The activities of SOD increased significantly, even higher than C, at the first 4d of fasting period, however which is then reduced continuously to below the control level. Other indicators cannot remain stable (show visible drop actually) as the extension of starvation, until in hunger to 16 days. (2)The degree of compensatory growth(CG) vary depend on the duration of starvation, as the increased of the gap of the mean weight between the experiment groups with different fasting time and the control group, as well as different value of SGR and length of fast growth phase in each groups. In this experiment, S1, S2 and S4 showed complete CG, S8 and S12 showed over CG, S16, S24 showed partial CG, and S32 showed non CG. (3) A significant positive linear relationship between special growth rate and feeding rate and food conversion efficiency are observed, This means the higher SGRs during the refeeding phase are introduced by both higher FCE and FR. (4) The changes of pepsin and HSI in experiment groups during refeeding phase showed:The higher FCEs are caused by the increased of the activity of pepsin mainly, while a low level of HSI only increased the FCEs at a very earlier time. A higher level of HSI promoted the accumulation and use of the energy in some groups. (5) There are no differences of mortality between control group and S1,S2,S4. However it increased significantly from S8 to S32. The changes of SOD during all period are in concordance with the mortality in experiment groups.3. A 72-day feeding trail was conducted to investigate compensatory growth of crayfish, Crayfish were divided into one control group(SROO), which were continuous feeding, and six experimental groups as follow:starvation 1d+re-feeding 1d(SR11); starvation 2d+ re-feeding 2d(SR22); starvation 4d+re-feeding 4d(SR44); starvation 6d+re-feeding 6d(SR66); starvation 8d+re-feeding 8d(SR88); starvation 12d+re-feeding 12d(SR1212); starvation 18d+re-feeding 18d(SR1818). The crayfish under starvation for 1d showed full compensatory growth while 2-6d showed over compensatory and 8-18d showed partial compensatory during the whole 72d experiment. The survive rate and SOD were significantly indifferent from control group within 4d starvation, but were remarkably lower than control group while the cycling starvation time was more than 6 days. No apparently different value of the survive rate was found from group SR66 to SR1818, while SOD was deceased with the increase of starvation time. The glycogen, HSI and digestive enzyme activities shows the same trend with the gross weight, while the flesh rate did not change so much. It indicated that the value of glycogen and digestive enzyme had a direct impact on compensatory growth of crayfish. Fitting the equations of single weight, SOD, liver glycogen, muscle glycogen, digestive enzyme and HSI along with cycling starvation time, according to which, the crayfish had the most rapid weight gain, SOD, digestive enzyme activities and glycogen after 3 to 4 days cycling starvation, and occurred the point of no return (PNR) by 15-day starvation.These results indicate that the nutrition-restricted starvation and feed deprivation affected the growth and physiological indicators of crayfish with different outcomes, while the similar mechanism of compensatory growth is also found by the crayfish with long-term and cycling feeding regimes.更多还原