Verdaulichkeit,wachstum und körperzusammensetzung von karpfen (Cyprinus carpio L.) nach verfütterung verschiedener stärkearten

Maisstärke, Maisquellstärke, Weizenstärke, Weizenquellstärke, Kartoffelstärke oder Maniokmehl werden in Anteilen von 41% bzw. 46,7% (Maniokmehl) einer Basalration zugemischt. Jede Versuchsration wurde an insgesamt 33 Karpfen (Cyprinus carpio L.) (drei Becken mit je 11 Karpfen) in einer Menge von 1,8‐ 2,0 % der Lebendmasse über eine einheitliche Versuchsdauer von 118 Tagen ab einer mittleren Lebendmasse von 146 g verfüttert. Die 4 Rationen auf Basis von Mais‐ bzw. Weizenstärke weisen insgesamt die gleiche, hohe Energieverdaulichkeit von etwa 90% auf. Die Zumischung von Kartoffelstärke bzw. von Maniokmehl verringert die Energieverdaulichkeit um 5 % bzw. 3% signifikant. Das Wachstum und der Futteraufwand werden durch die unterschiedlichen Stärkearten nicht beeinflußt. Zu Versuchsende weisen die Karpfen eine mittlere Masse von 520 g auf. Die Ganzkörper haben insgesamt mittlere Gehalte an Rohasche, Rohprotein und Gesamtfett bzw. Energie von 2,8, 15,7,9,4% bzw. 7,4 kJ pro g Frischmasse. Allerdings führt die Zumischung von Kartoffelstärke bzw. Maniokmehl zu einer deutlich geringeren Energieretention gegenüber Mais‐ und Weizenstärke, da die Trockensübstanz‐, Fett‐ und Energiegehalte dieser Karpfen signifikant niedriger sind.     

大头鲤原种种群的遗传现状

大头鲤(Cyprinus pellegrini)是一种云南高原湖泊特有的国家Ⅱ级重点保护鱼类。土著种大头鲤与外来种鲤(C.carpio)的渐渗杂交在星云湖野生种群中已经广泛发生。本研究结合形态和微卫星及线粒体DNA分析检测了螺蛳铺大头鲤原种种群的遗传现状。结果显示,螺蛳铺大头鲤样本所有个体在形态上位于大头鲤与鲤的参照样本之间;在微卫星因子对应分析中也显示,其位于大头鲤与鲤的参照样本之间,但与大头鲤参照样本较为相似;在线粒体DNA分析中显示,都具有鲤的单倍型。中间性形态特征以及核基因组成与线粒体基因组成的不一致现象,表明螺蛳铺大头鲤样本均为杂种个体。因此,螺蛳铺大头鲤原种种群可能是一个杂种种群,有必要重新建立大头鲤人工繁殖计划。     

Changes of carp myosin subfragment-1 induced by temperature acclimation

Summary Heavy meromyosin subfragment-1 (S1) was prepared by -chymotrypsin from myosin of carp acclimated to either 10°C or 30°C for a minimum of 5 weeks. The objective of these studies was to document thermally-induced changes in the myosin molecule and to extend previous observations. Ca²⁺- and K⁺ (EDTA)-ATPase activities of cold-acclimated carp S1 were 1.1 and 0.8 mol P_i·min^-1·mg^-1, respectively, and these values did not differ significantly from those of warm-acclimated carp. The inactivation rate constant (K_D) of S1 from cold-acclimated carp was 32.1x10^-4· s^-1, compared to 13.2x10^-4·s^-1 for warm-acclimated carp. The maximum initial velocity of acto-S1 Mg²⁺-ATPase activity at pH 7.0 in 0.05 M KCl was 9.3 s^-1 with cold-acclimated carp, about 3.7 times higher than that for warm-acclimated carp. However, no significant difference was observed in the apparent affinity of S1 to actin. Peptides maps of the heavy chain of S1 were different and suggested distinct isoforms for the myosins from warm- and cold-acclimated muscle.Abbreviations ATPase adenosine 5-triphosphatase - DTNB 5,5-dithiobis (2-nitrobenzoic acid) - DTT dithiothreitol - EDTA ethylenediaminetetraacetic acid - EGTA ethyleneglycol bis (-aminoethylether)-N,N,N,N-tetraacetic acid - K _D inactivation rate constant - K _m apparent dissociation constant - P _i inorganic -phosphate - PMSF phenylmethane-sulfonyl fluoride - S ₁ heavy meromyosin subfragment-1 - SDS sodium dodecyl sulfate - SDS-PAGE SDS-polyacrylamide gel electrophoresis - TPCK N-tosyl-l-phenylalanyl chloromethyl ketone - V _max maximum initial velocity     

Neural Regulation of Dark-Induced Abundance of Arylalkylamine N-Acetyltransferase (AANAT) and Melatonin in the Carp (Catla catla) Pineal: An In Vitro Study

In all the vertebrates, synthesis of melatonin and its rhythm-generating enzyme arylalkylamine N-acetyltransferase (AANAT) reaches its peak in the pineal during the night in a daily light-dark cycle, but the role of different neuronal signals in their regulation were unknown for any fish. Hence, the authors used specific agonist and antagonists of receptors for different neuronal signals and regulators of intracellular calcium (Ca²⁺) and adenosine 3',5'-cyclic monophosphate (cAMP) in vitro to study their effects on the abundance of AANAT and titer of melatonin in the carp (Catla catla) pineal. Western blot analysis followed by quantitative analysis of respective immunoblot data for AANAT protein, radioimmunoassay of melatonin, and spectrophotometric analysis of Ca²⁺ in the pineal revealed stimulatory effects of both adrenergic (α₁ and β₁) and dopaminergic (D₁) agonists and cholinergic (both nicotinic and muscarinic) antagonists, inhibition by both adrenergic and dopaminergic antagonists and cholinergic agonists, but independent of the influence of any agonists or antagonists of α₂-adrenergic receptors. Band intensity of AANAT and concentration of melatonin in the pineal were also enhanced by the intracellular calcium-releasing agent, activators of both calcium channel and adenylate cyclase, and phophodiesterase inhibitor, but suppressed by inhibitor of calcium channel and adenylate cyclase as well as activator of phophodiesterase. Moreover, an inhibitory effect of light on the pineal AANAT and melatonin was blocked by both cAMP and proteasomal proteolysis inhibitor MG132. Collectively, these data suggest that dark-induced abundance of AANAT and melatonin synthesis in the carp pineal are a multineuronal function, in which both adrenergic (α₁ and β₁, but not α₂) and dopaminergic signals are stimulatory, whereas cholinergic signals are inhibitory. This study also provides indications, though arguably not conclusive evidence, that in either case the neuronal mechanisms follow a signal-transduction pathway in which Ca²⁺ and cAMP may act as the intracellular messengers. It also appears that proteasomal proteolysis is a conserved event in the regulation of AANAT activity in vertebrates. (Author correspondence: dgp_skmaitra@yahoo.co.in)     

复合酶制剂EA－2对鲤生长的影响

利用复合酶制剂ＥＡ－２在池溏中饲养鲤５０ｄ,实验组鲤尾增重率高于对照组１２．３—２７．５％,而饲料系数低于对照组１８．７６—１０．８９％。实验组鲤肝胰脏淀粉酶活力显著增加,而肝、胰脏蛋白酶活力显著降低,实验组鲤肠内蛋白酶活力和淀粉酶活力均显著增加。酶制剂对鲤肥满度、肝胰比、内脏比、肝胰脏和背部肌肉的生化成份均无显著影响。     

Temperature acclimation of gross cardiovascular morphology in common carp (Cyprinus carpio)

Temperature is of fundamental importance in the functioning of the cardiovascular system of ectothermic fish, with cold-induced ventricular hypertrophy and increased red muscle mass being reported in a number of fish species upon cold acclimation. This study demonstrates a non-linear cold-induced ventricular hypertrophy in common carp (relative ventricular mass (RVM)=0.086±0.003%, 0.074±0.005% and 0.074±0.004% at 5, 15 and 25 °C, respectively), but a cold-induced atrophy of the lateral red muscle mass (RMM) with respect to total muscle mass (2.504±0.554%, 3.982±0.818% and 4.490±0.256% at 5, 15 and 25 °C, respectively). The ventricular hypertrophy in carp acclimated to 5 °C reflects a compensation against the increased workload of pumping viscous blood at low temperatures and the negative inotropic effects of the cold, whereas atrophy of the red muscle is likely due to disuse resulting from reduced locomotory activity in the cold.