Purification and characterization of two anionic trypsins from the hepatopancreas of carp

SUMMARY: Two trypsins, designated as trypsin A and trypsin B, have been purified from the hepatopancreas of carp. The purification procedures consisted of ammonium sulfate fractionation, and chromatographies on DEAE-Sephacel, Ultrogel AcA54 and Q-Sepharose. Trypsin A was purified to homogeneity with the molecular mass of approximately 28 kDa, while trypsin B gave two close bands of 28.5 kDa and 28 kDa on sodium dodecylsulfate polyacrylamide gel electrophoresis both under reducing and non-reducing conditions. On native-PAGE, both trypsin A and trypsin B showed a single band. Trypsin A and trypsin B revealed optimum temperature of 40°C and 45°C, respectively, and shared the same optimum pH 9.0 using Boc-Phe-Ser-Arg-MCA as substrate. Both enzymes were effectively inhibited by trypsin inhibitors and their susceptibilities were similar. The NH₂-terminal amino acid sequences of trypsin A and trypsin B were determined to 37th and 40th amino acid residue, respectively. Their sequences were very homologous, but not identical to that of a trypsin-type serine proteinase from carp muscle and these of other trypsins. Immunoblotting test using the antibody raised against trypsin A cross-reacted with trypsin B positively.     

Spatial variability of common carp populations in relation to lake morphology and physicochemical parameters in the upper Midwest United States

Weber MJ, Brown ML, Willis DW. Spatial variability of common carp populations in relation to lake morphology and physicochemical parameters in the upper Midwest United States.
Ecology of Freshwater Fish 2010: 19: 555–565. © 2010 John Wiley & Sons A/S Abstract – Common carp (Cyprinus carpio) is a widespread invasive species that is tolerant of a wide range of environmental conditions. Despite the circumpolar distribution of the species, limited information is available describing factors related to spatial variation in population characteristics. Eighty‐four lakes and impoundments in the upper Midwest United States were sampled to investigate the relationships of common carp relative abundance with size structure, condition and growth rates. We also investigated abiotic factors (lake morphology, physical solids and water quality) that may broadly influence common carp populations. Common carp size structure and condition were inversely related to relative abundance. Common carp relative abundance increased and size structure shifted to smaller individuals with increased lake depth, whereas lake surface area, watershed:surface area ratio and physical solids were also important in explaining common carp abundance and size structure. Common carp condition was best explained by water quality parameters and increased with metrics of lake productivity. We conclude that knowledge of factors associated with variation in common carp populations among lakes provides insights into the autecology and broad provisions for management of this generalist invasive species.     

微卫星分子标记指导镜鲤群体选育

本文用26个扩增效果好的微卫星分子标记分析了镜鲤（Cyprinus carpio L.）养殖亲本群体的遗传结构,指导其群体选育。本研究共检测到153个等位基因,片段大小为108~400 bp,平均等位基因数（A）5.8846个,平均有效等位基因数（Ne）2.8625个,平均观察杂合度（Ho）0.5063,平均期望杂合度...     

The pigmenting effect of different carotenoids on fancy carp (Cyprinus carpio)

The optimal concentration of a panel of individual and combined carotenoid sources on skin pigmentation in fancy carp was investigated by nine experimental diets that were formulated and supplemented with astaxanthin at 25 mg kg^?1, lutein at 25 and 50 mg kg^?1, β‐carotene at 25, 50 and 75 mg kg^?1, and lutein combined with β‐carotene at 25 : 25 and 50 : 50 mg kg^?1, while a diet without supplemented carotenoid served as a control. The results showed that serum TC of fish fed diets containing supplemented with lutein plus β‐carotene at 25 : 25; 50 : 50 mg kg^?1 and lutein 50 mg kg^?1 diet were higher than the other treatments (P ≤ 0.05). Serum TC of the respective treatments was 6.2 ± 2.0, 7.8 ± 3.3 and 7.3 ± 1.9 μg mL^?1 serum, respectively. Fish fed diets combined with lutein and β‐carotene at 25 : 25, 50 : 50 mg kg^?1 and lutein 50 mg kg^?1 diet had serum astaxanthin concentrations similar to fish fed the diet with astaxanthin alone at 25 mg kg^?1. Serum astaxanthin concentrations was 0.7 ± 0.01, 0.9 ± 0.01, 0.4 ± 0.02 and 1.7 ± 0.18 μg mL^?1 serum, respectively. The chromaticity of fish body skin of red and white position was assessed by colourimetry using the CIE L*a*b (CIELAB) system. Pigmentation response of skin redness of fancy carp fed with diets combined with lutein and β‐carotene at 25 : 25, 50 : 50 mg kg^?1 and lutein 50 mg kg^?1 were higher than other treatments (P ≤ 0.05) but they were similar to fish fed with 25 mg kg^?1 astaxanthin diet. The redness (a* values) of fish fed diets with diets combined with lutein and β‐carotene at 25 : 25, 50 : 50 mg kg^?1 and lutein 50 mg kg^?1 were 28.3 ± 0.53, 29.9 ± 1.38, 28.8 ± 3.95 and 28.5 ± 2.49, respectively. After 3 weeks of feeding the experimental diets, the fish fed on a diet without carotenoid supplement for one week demonstrated that the same three groups still retained their redness and had an overall tendency to improve skin colouring. Finally, concentrations 50 mg kg^?1 of lutein, or the combination of lutein and β‐carotene at 25 : 25 mg kg^?1 showed the highest efficiency for improving skin pigmentation and redness of skin.     

草鱼不同混养模式下围隔底泥反硝化、硝化和氨化速率

应用乙炔抑制法测定了草鱼(Ctenopharyngodon idellus)不同混养模式围隔底泥的硝化、反硝化和氨化速率,以探究草鱼不同混养模式对池塘底泥－水界面N元素动态变化的影响,并为草鱼养殖模式的优化提供必要的参考依据.混养组合分别为一元组（草鱼）、二元组（草鱼+鲢、草鱼+凡纳滨对虾）、三元组（草鱼+鲢+凡纳滨对虾,设2种放养比例）.结果显示:1）草鱼不同混养模式中底泥的反硝化速率范围为0～734.15 μmol/(m2·d),硝化速范围为0～1 209.20 mmol/(m2·d),化速率范围为0～41.25 mmol/(m2·d).2)草鱼不同混养模式底泥的反硝化速率较高,与很多河口和湖泊数值接近；在养殖中期,底泥的硝化速率很小甚至检测不到；底泥的氨化速率呈逐月递增趋势,以三元混养组最高.3）混养组中凡纳滨对虾(Litopenaeus vannamei)的放养密度越大,草鱼的放养密度越小,反硝化作用出现得越早,但反硝化速率很难保持开始的水平；反之,反硝化作用出现得较晚,并会随着养殖周期的推移迅速升高；放养种类越单一,底泥的硝化速率越低,且鲢(Hypophthalmichthys molitrix)放养密度越高,硝化速率越高.从养殖模式优化的角度来看,草鱼三元混养组要优于单养和二元混养组,但三元混养组中两种放养密度各有优劣,有待进一步优化以确定最佳放养比例.     

The anaesthetic‐like effect of tea tree oil in common carp Cyprinus carpio L.

This study investigated the efficacy of tea tree oil (TTO) as an anaesthetic for common carp, Cyprinus carpio L., by estimation of behaviour changes and responsiveness to being taken out of the water. All applied concentrations (from 0.2 to 0.6 mL L⁻¹) resulted in sedation and immobilization. The lowest effective concentration (induction time ≤3 min, recovery time ≤10 min after 15 min of exposure) was 0.5 mL L⁻¹. Exposure in excess of 30 min at a concentration of 0.5 mL L⁻¹ caused mortality. TTO displayed distinct general anaesthetic‐like properties, fulfilling the basic requirements for a potent fish anaesthetic.     

Effects of dietary thiamin supplement on growth,body composition and intestinal enzyme activities of juvenile Jian carp (Cyprinus carpio var. Jian)

A total of 1050 juvenile Jian carp (Cyprinus carpio var. Jian) (8.20 ± 0.02 g) were fed diets containing seven graded levels of thiamin (0.25, 0.48, 0.79, 1.06, 1.37, 1.63 and 2.65 mg kg^?1) for 60 days to investigate the effects of thiamin on growth, body composition and digestive enzyme activities. Percent weight gain (PWG), feed intake and feed efficiency (FE) were the lowest in fish fed the basal diet (P < 0.05). Protein productive value and lipid productive value increased with increasing dietary thiamin levels up to 1.06 and 0.79 mg kg^?1 diet, respectively (P < 0.05). Body protein and lipid increased with increasing dietary thiamin levels (P < 0.05), while moisture and ash of fish carcasses decreased with the increase in dietary thiamin supplementation (P < 0.05). Intestinal folds height had a similar trend to PWG (P < 0.05). Activities of α‐amylase, lipase, trypsin, Na⁺, K⁺‐ATPase, alkaline phosphatase and gamma‐glutamyl transpeptidase in intestine were all affected by the dietary thiamin (P < 0.05). In conclusion, thiamin could improve growth and intestinal enzyme activities of juvenile Jian carp. The dietary thiamin requirement of juvenile Jian carp (8.0–60.2 g) based on PWG was 1.02 mg kg^?1 diet.     

两种鲤鲫杂交回交子代染色体核型分析及比较

采用PHA和秋水仙素体内注射制备两种鲤鲫杂交回交子代鱼（鲤鲫杂交♀×德国镜鲤♂；鲤鲫杂交♀×鲤♂）的染色体。结果表明：两种鲤鲫杂交回交子代染色体组由150条染色体组成，按着丝粒位置染色体组型可分为四组，每个染色体小组均由三条同源染色体组成。其中鲤鲫杂交♀×鲤♂回交的染色体数目为3n=150，染色体臂数NF=234，其核型公式为：3n=60m＋24sin＋36st＋30t；鲤鲫杂交♀×德国镜鲤♂回交染色体数目为3n=150，染色体臂数NF=258，其核型公式为：3n=63m＋45sin＋12st＋30t。     

鲢、鳙对三角帆蚌池塘藻类影响的围隔实验

以浙江金华汤溪威旺养殖基地的三角帆蚌养殖水体为研究对象,通过围隔实验比较研究了单养鲢、鳙和三角帆蚌的池塘浮游植物密度、生物量和优势种(属)组成等的差异,以及养蚌池混养鲢鳙对水体浮游植物密度、生物量以及优势种变化的影响。结果表明,养蚌(10#)围隔的浮游植物平均密度和生物量均显著高于高密度鲢(12#)围隔(P<0.05),其蓝藻数量及生物量显著高于高密度鲢(12#)和低密度鳙(13#)围隔(P<0.05),绿藻数量则显著低于低密度鲢单养(11#)围隔(P<0.05)。在鱼蚌混养的情况下,单养蚌(10#)围隔浮游植物平均数量显著高于鲢-蚌混养(15#,16#)和鳙-蚌混养(17#,18#)围隔(P<0.05),其蓝藻数量及生物量极显著高于鲢-蚌混养(15#,16#)或鳙-蚌(17#,18#)围隔(P<0.01),其绿藻数量显著低于混养高密度鲢(16#)或低密度鳙(17#)的混养围隔(P<0.05)。研究结果充分说明,鲢、鳙和三角帆蚌三者对水体藻类组成的影响有别,三角帆蚌养殖池中适当混养鲢或鳙可以有效控制蓝藻(铜绿微囊藻)的生长,促进绿藻(四尾栅藻)的生长,并最终有利于三角帆蚌的养殖,混养鲢密度的增加有利于控制藻类生长,而鳙密度的增加促进了裸藻等中大型藻类的生长。     

草鱼巨噬细胞的集结及相关的组织变化

给草鱼腹腔注射细微炭粒（墨汁）后不同时间取样，比较观察了草鱼胸腺、肝、脾、头肾和肾组织中巨噬细胞集结（ｍ ａｃｒｏｐｈａｇｅ ａｇｇｒｅｇａｔｉｏｎ ， Ｍ Ａ）状况及相应组织的变化。结果表明，在头肾和脾组织中， Ｍ Ａ 的数量和体积均较肝和肾中的多而大，胸腺中所产生的 Ｍ Ａ 数量较肝和肾中的少，体积也小；注射墨汁后 １～３ 周内，在胸腺、头肾、肝和脾组织中， Ｍ Ａ 的数量和体积均有不同程度的增加，但在注射墨汁后第 ４ 周的肾组织中， Ｍ Ａ 的体积缩小而且密度降低，同时肾组织结构有逐渐恢复的趋势，可能是由于 Ｍ Ａ 分解后通过肾小球和肾小管排泄到膀胱或体外的缘故。对草鱼 Ｍ Ａ 的组织分布、排除等分析认为， Ｍ Ａ 可作为草鱼非特异细胞防御作用的解剖学和细胞学的一种生物标记。