乌鳢血液指标的研究

对乌鳢的红、白细胞数、血红蛋白等血液指标进行了研究。结果如下:乌鳢的红细胞数为(369.83±51.03)万个/mm3;白细胞数为(5.88±1.27)万个/mm3;血红蛋白为(9.54±0.61)g/100ml;白细胞分类计数中淋巴细胞占(58.23±5.67)%;嗜中性细胞占(28.10±4.36)%;单核细胞占(9.10±4.02)%;嗜碱性细胞和嗜酸性细胞观测到的数目很少;血沉为(1.50±0.12)mm/h;红细胞膜最大抵抗值为(0.38±0.02)%;红细胞大小为(10.02±0.52)μm×(7.01±0.24)μm(长径×短径);红细胞核为(4.22±0.27)μm×(1.96±0.18)μm(长径×短径)。  

饲料中添加谷胱甘肽对草鱼生长、生理指标和抗病力的影响

选用初始体质量约8.50 g的草鱼(Ctenopharyngodon idella),在56 d的饲养期中分别投喂添加5种不同剂量谷胱甘肽(GSH)(添加量分别为0 mg/kg、100 mg/kg、200 mg/kg、300 mg/kg和400 mg/kg)的试验饲料,观察GSH对草鱼生长、生理指标和抗病力的影响。结果表明,饲料中添加GSH能够提高草鱼特定生长率、存活率和饲料效率。其中,300 mg/kg GSH组草鱼的特定生长率和400 mg/kg GSH组草鱼的存活率显著高于对照组;添加GSH各组草鱼的饲料效率均显著高于对照组,当添加量为200 mg/kg时草鱼饲料效率达到最高。与对照组相比,饲料中添加GSH的各组草鱼肝胰指数明显升高,其中200 mg/kg组达到显著水平。饲料中添加GSH能够提高血清IGF-1水平,其中300 mg/kg和400 mg/kg组显著高于对照组。与对照组相比,各实验组草鱼血液白细胞数目有不同程度升高,其中300 mg/kg和400 mg/kg组均达到显著水平。饲料中添加GSH可以提高草鱼对嗜水气单胞菌的抵抗能力,其中200 mg/kg GSH组草鱼攻毒后存活率达到最高。以特定生长率为判定指标,GSH在草鱼饲料中的适宜添加量为350 mg/kg。  

养殖密度对克氏原螯虾幼虾生长、消化酶活力和生理生化指标的影响

以体质量(0.015±0.004)g克氏原螯虾幼虾为研究对象,研究了50、100、300、600、900尾/m25种养殖密度对克氏原螯虾幼虾生长、消化酶活力和生理生化指标的影响,实验周期为30 d。结果显示,克氏原螯虾幼虾的终末体质量随着养殖密度的增大而减小。胃蛋白酶、类胰蛋白酶和淀粉酶活力随着养殖密度的增大表现出减小趋势,纤维素酶和脂肪酶活力在5种养殖密度下变化规律不显著(P>0.05)。克氏原螯虾幼虾体内水分含量在5种养殖密度下差异较小(P>0.05);粗蛋白含量随养殖密度的升高呈增高趋势,由54.02%增高至60.75%(P<0.05);粗脂肪含量不断减少(P<0.05),由26.19%减少至19.19%(P<0.05)。随着养殖密度的增大,克氏原螯虾幼虾肌肉葡萄糖的含量呈下降趋势(P<0.05),甘油三酯、总蛋白、尿素氮和胆固醇含量呈不断增多趋势(P<0.05)。克氏原螯虾幼虾肝胰腺葡萄糖、甘油三酯、总蛋白和尿素氮含量随着养殖密度的增大呈不断增多趋势。结果表明,高密度养殖对克氏原螯虾幼虾生长和消化酶活力具有一定负面影响,体内蛋白、脂肪、葡萄糖和尿素氮等物质的含量也随着养殖密度的增大而发生变化。  

饥饿和再投喂对哲罗鱼幼鱼血液生理生化指标的影响

将哲罗鱼(Hucho taimen)幼鱼进行7 d、14 d、21 d和28 d的饥饿处理后恢复投喂,研究饥饿和再投喂对其血液生理与生化指标的影响,各组实验期为56 d。结果显示:饥饿过程中哲罗鱼幼鱼血液红细胞数、血红蛋白和白细胞数均在饥饿14 d后显著上升(P<0.05),21 d后则开始下降;饥饿7 d后血糖浓度显著下降(P<0.05),14 d后趋于稳定;总蛋白、球蛋白和白蛋白均呈下降趋势,分别在饥饿的第21天、28天和7天后与饥饿前差异显著(P<0.05);甘油三酯和总胆固醇分别在饥饿7 d和14 d后显著下降(P<0.05);谷丙转氨酶和谷草转氨酶均在饥饿14 d后显著下降(P<0.05);碱性磷酸酶在饥饿7 d后显著下降(P<0.05);饥饿7 d后Na+和Cl-浓度显著下降(P<0.05),14 d后均显著回升(P<0.05);Ca2+浓度在饥饿14 d后显著升高(P<0.05),28 d后显著降低(P<0.05);K+浓度在饥饿后升高,但与饥饿处理前比较无显著性差异。恢复投喂结束后,哲罗鱼幼鱼血液的各项生理生化指标均有不同程度的恢复。  

The spatial distribution of cod (<i>Gadus morhua</i> L.) spawning grounds in the Kattegat, eastern North Sea

Similar to many other commercial marine fish species, Atlantic cod (Gadus morhua L.) migrate towards specific sites at spawning. These temporal aggregations are generally the most targeted by the commercial fishery. The Kattegat cod has undergone a substantial reduction over the past 25 years and both stock size and spawning stock biomass have remained at very low levels since the end of the 1990s. There is, therefore, an urgent need to map and document spawning grounds still in use. In the present study, spawning sites of Atlantic cod were identified in the Kattegat using a combination of commercial and fishery independent data from 1996 to 2004. Moreover, putative spawning and non-spawning areas were also sampled before and during the reproductive season between 2002 and 2006, and the proportion of mature females together with the individual physiological status were used to validate and strengthen the spatial analyses.

The spatial analyses identified several spawning areas in the region and two areas in the southeastern part of the Kattegat which appeared to be the most important. The results showed the presence of cod spawning aggregations, although reduced in size, in areas that have been utilized for more than 25 years according to historical information. Some local spawning grounds may have also disappeared. The proportion of mature females was higher in putative spawning than in non-spawning areas (p < 0.001) and females from spawning areas had higher gonadosomatic (p < 0.05) and hepatosomatic (p < 0.001) indices than those from non-spawning areas.

Knowledge of stock spatial and temporal distribution is essential in designing recovery strategies for depleted fish populations. The unambiguous stability of the locations of spawning aggregations over time, as shown in this study, represents a useful aid in order to efficiently implement a recovery plan for the collapsing cod stock in this area.  

两种养殖条件下牙鲆的血液生理生化指标比较分析

对池塘和室内水泥池养殖牙鲆的血液生理生化指标进行了比较研究,每种养殖条件下分别选取两种不同体重规格的牙鲆,即池塘小规格牙鲆（PSJF）、池塘大规格牙鲆（PBJF）、室内小规格牙鲆（ISJF）和室内大规格牙鲆（IBJF）作为研究对象.对全部试验鱼5项血液生理指标和13项血清生化成分进行了测定分析,结果显示,PSJF和PBJF的红细胞数量（RBC）均显著低于ISJF和IBJF（P＜0.05）,且前者红细胞沉降率（ESR）、红细胞脆性（EOF）、白细胞数量（WBC）及白细胞中淋巴细胞所占比例均显著高于后者（P＜0.05）.PSJF和PBJF的血清葡萄糖（GLU）、总蛋白（TP）、白蛋白（ALB）、球蛋白（GLO）、肌酐（CREA）、总胆固醇（CHOL）、甘油三酯（TG）浓度及碱性磷酸酶（AKP）活性均显著高于ISJF和IBJF（P＜0.05）,仅PSJF的乳酸脱氢酶（LDH）活性低于ISJF和IBJF（P＜0.05）.血清氯离子（Cl-）、钙离子（Ca2＋）浓度及谷草转氨酶（AST）、谷丙转氨酶（ALT）活性在各个试验组间均无显著差异（P＞0.05）.血液生理和生化指标的差异表明,池塘养殖牙鲆可能在呼吸代谢要求上低于室内水泥池养殖牙鲆,而在免疫水平和营养物质代谢水平上高于室内水泥池养殖牙鲆.  

Influence of hatchery diets on early grow-out of the Cortez oyster Crassostrea corteziensis in Sinaloa, Mexico

We measured the growth and physiological condition of juveniles of the Cortez oyster Crassostrea corteziensis during the early grow-out phase in Sinaloa (Mexico) after using three experimental diets during the hatchery period: (1) 1:1 blend of the microalgae Isochrysis galbana and Chaetoceros muelleri as the control group; (2) mix of the same microalgae replaced by 50% of its wet weight with cornstarch; and (3) mix of the two microalgae replaced by 50% its wet weight with wheat flour. Specimens were cultivated under suspension conditions for 60 days and monitored weekly for growth (shell height and wet and dry weight) and the first 15 days for physiological response (condition index, digestive gland index and muscle index). Juveniles fed exclusively on microalgae attained larger sizes and had higher digestive gland and muscle indices, while those fed microalgae with cornstarch gained more biomass (wet and dry weight) and reached a better condition. The lowest values of these indicators occurred in oysters fed microalgae with wheat flour. Statistical data revealed that differences in the growth and condition of specimens between treatments were slight, confirming that mixed diets (particularly microalgae/cornstarch) have potential application for reducing hatchery-operating costs without affecting the performance of planted juveniles in the field.  

池塘循环水槽养殖模式下吉富罗非鱼的生长及生理响应变化

以吉富罗非鱼(GIFT Tilapia)为研究对象,设计以传统池塘养殖模式为对照组A(5尾/m2),池塘循环水槽养殖模式为试验组B(180尾/m2)和C(270尾/m2),探讨在池塘循环水槽养殖模式下,吉富罗非鱼不同养殖密度的生长特性和生理指标的变化,评估吉富罗非鱼在池塘循环水槽养殖模式下的适宜养殖密度。经过120d的养殖,B组吉富罗非鱼终末体重、特定生长率和绝对生长率显著高于A组和C组(P<0.05)；A组存活率最高,C组最低；试验组体重差异系数和饵料系数小于对照组。试验组吉富罗非鱼血清谷丙转氨酶、谷草转氨酶、溶菌酶水平和肝脏HSP70 mRNA的相对表达量在养殖周期内均呈现先上升后下降的趋势。试验组B血清皮质醇、甘油三酯水平在前期与对照组A有差异(P<0.05),葡萄糖水平在整个养殖周期内与对照组无差异；试验组C组皮质醇和葡萄糖水平在整个养殖周期内持续上升(P<0.05),甘油三酯水平在整个养殖周期内无差异。研究结果表明,试验组B吉富罗非鱼在养殖前期受到环境胁迫,中后期逐渐适应环境；试验组C在整个养殖周期内处于应激状态。综合考虑罗非鱼生长和血清指标得出,池塘循环水槽养殖罗非鱼的适宜养殖密度为180/m2,在该密度下罗非鱼能适应养殖环境,养殖效果优于传统养殖模式。  

低盐急性胁迫对仿刺参相关生理指标的影响

通过模拟仿刺参养殖池塘雨季的盐度变化, 选用2 龄仿刺参(Apostichopus japonicus)为研究对象, 刺参体重(16.93±3.08) g, 研究盐度骤降及胁迫恢复对仿刺参体腔液相关生理指标的影响。盐度先由30 以每6 h 变化3 个盐度的速度下降至18, 然后在盐度18 保持96 h, 随后盐度以相同速度上升恢复至30, 并保持24 h。结果显示, 各盐度取样点间仿刺参体腔液渗透压、体腔液总蛋白浓度、Na+、K+、Cl–浓度与盐度的变化趋势一致, Na+、K+、Cl–浓度均在盐度下降到18 时达到最低值, 分别为(131.15±14.42) mmol/L, (6.08±0.24) mmol/L 和(141.76±2.13) mmol/L;而Ca2+浓度一直呈上升趋势。体腔液中Na+-K+-ATP 酶活力在盐度18 并保持4 d 后显著高于其他组(P<0.05), 盐度对其体腔液中Na+-K+-ATP 酶活力的影响与体腔液渗透压变化趋势不一致。盐度胁迫对谷丙转氨酶活力无显著影响。结果表明, 盐度胁迫对仿刺参渗透调节能力有显著影响, 实验中体腔液渗透压与体腔液Na+、K+、Cl–浓度有一定的相关性。盐度胁迫对仿刺参的呼吸代谢产生的影响不显著。研究结果为丰富仿刺参适应环境盐度的机制提供基础资料, 为进一步了解盐度胁迫下刺参的生理生态学特征以及今后的刺参增养殖生产提供参考。

  

RNA/DNA ratio is an early responding,accurate performance parameter in growth experiments of noble crayfish Astacus astacus (L.)

Recent intensification efforts of astacid culture considerably depend on the appropriate assessment of the animal's physiological condition both for research and application. We conducted a 4 weeks feeding experiment to assess temporal resolution and accuracy of different response parameters (RNA/DNA ratio, RNA per wet weight, carapace length, wet weight, specific growth rate). Juvenile noble crayfish were exposed to five feeding regimes that differed in feeding frequency and food availability. Continuous growth was detected in all feeding regimes with individual increase up to 90% (wet weight) and 17% (carapace length), respectively. Morphometric parameters allowed separation of three weight‐groups or two length‐groups. During the experimental period RNA/DNA ratios showed both decrease (?17%) and increase (+35%), with superior accuracy than morphometric parameters, separating four groups. Based on RNA/DNA ratios, different feeding regimes were detected earlier, with two groups separated already after 3 weeks. RNA/DNA ratio was clearly superior to RNA per unit wet weight, as the latter failed to detect any differences between groups. In conclusion, RNA/DNA ratio is a valuable tool in nutritional studies with freshwater crayfish if overall growth is the key variable of interest.