Lipid content of Calanus finmarchicus during overwintering in the Faroe–Shetland Channel

Lipid class contents and composition of the copepodite stage CV and adult female Calanus finmarchicus were measured from the autumn to the spring along a transect crossing the Faroe–Shetland Channel. The data give a detailed vertical resolution of lipid content of C. fin-marchicus before, during and after the time of diapause. In the deep water, where C. finmarchicus was in diapause, the wax ester (WE) content did not change between the autumn and spring with the exception of that of females, which showed a significant decrease in lipid content by March. The concentrations of lipids were lower and more variable in both CV and females in surface waters over the sampling period. In March, the lipid concentration of both CV and females decreased significantly with decreasing depth. The triacylglycerol (TAG) content of both CV and females was high in October at all depths but had almost disappeared by December. The TAG was either utilized during this time period or converted to WE. TAG was most prominent in October and again in February in copepods in the upper water column. A simple diagnostic model is presented that estimates how C. finmarchicus allocates energy reserves from lipids into various metabolic functions. The cost of diapause, molting, gonad formation and ascending from depth is estimated based on the time series data. The model indicates that the major portion of the stored lipid goes into gonad formation, in physical ascent and in basic metabolism during ascent, whereas maintenance of diapause and molting is not expensive in terms of lipid utilization.     

乳山寨滩涂缢蛏半人工采苗的研究

为解决北方沿海缢蛏养殖的苗种问题，在乳山寨滩涂建立缢蛏半人工采苗场，对苗坪适时进行翻耕平整，加强培育管理，１９９３年４ｈ采苗场共采蛏苗８７７０万粒，平均２２１５粒／，平均壳长２．５ｃｍ；１９９４年４０ｈ采苗场共采蛏苗５亿粒，平均１４２８粒／，平均壳长２ｃｍ。结果发现，附苗前翻松平整的苗坪附苗数量远高于未翻松平整的苗坪。山东沿海移养缢蛏性腺于９月中旬至１０月上旬进入成熟期，１０月上、中旬开始放散     

Variations in fatty acids composition of pikeperch (Sander lucioperca) liver with respect to gonad maturation

Abstract –  We examined seasonal variations in liver condition factor, total lipid and fatty acid composition of maturing pikeperch ( Sander lucioperca) from Lake Eğirdir, Turkey. The spawning of pikeperch in Eğirdir Lake started in March, continued very fast during May and gradually ended in July as determined by measuring the gonadosomatic index. The total lipid content of male and female liver reached its highest level in September and November (the end of dense feeding period during which temperature decreased sharply), but declined to the lowest level in May (just after spawning). The highest level of liver condition factor was observed in January and March during which gonads mature rapidly. Palmitic acid was the predominant saturated fatty acid (SFA) in female and male liver. The ratio of monounsaturated fatty acids (MUFA) was higher than that of polyunsaturated fatty acids (PUFA) in both sexes. Docosahexaenoic acid (22:6 n -3), eicosopentaenoic acid (20:5 n -3) and arachidonic acid (20:4 n -6) were the predominant PUFA. Seasonal variations in PUFA were more evident than that in other fatty acids. PUFA, especially the n -3 fatty acids ratio, increased to the maximum level during the sharp decreases in temperature (in November). However, the amount of PUFA decreased to the lowest level in reproductive period. The results suggest that the ratio of pikeperch liver fatty acids is influenced by gonad maturation and temperature variations and that pikeperch requires a large amount of PUFA and the n -3 fatty acids for the development of gonads.     

罗氏沼虾脑保性腺激素的步分离及活性检测

用ＳephadexG-50对罗氏沼虾脑抽提液进行了柱层析，发现洗脱液中的第二个峰中的６３－７４组分可非常显著地促进体外的罗氏沼虾卵母细胞直径增大，进一步检测，发现其中仅６３－６５组分可显著地促进体外培养的罗氏沼虾卵巢的总蛋白合成，进行日本沼虾肌肉主射可显著地促进其卵巢发育，６３组分的分子量在７kD以下，结果表明，罗氏沼虾脑中存在蛋白质性质的促性腺激素。     

海湾扇贝性腺发育的生物学零度

性腺发育的生物学零度是生物的繁殖习性和生物积温研究中的一个重要指标。正如菊地省吾提出皱纹盘鲍性腺发育的生物学零度以后,人们已可以通过控制积温的方法有效地预报和控制鲍鱼的产卵。因此研究海湾扇贝性腺发育的生物学零度,在海湾扇贝的繁殖理论研究以及海湾扇贝的工厂化人     

猪胚胎干细胞的分离培养

收集26-27d的猪胚胎分离原始生殖细胞(Primordial germ cells，PGCs)，培养在STO细胞饲养层上生长，形成EG细胞。EG细胞具有干细胞所具有的显著特性，形态，多能性和种系的延续，AKP染色阳性，并能在体外分化；分别将PGCs用三种不同的培养基培养，在形成EG细胞集落的数量和EG细胞分化上有着明显的差距，说明血清的质量和浓度以及细胞因子对干细胞的生成和增殖有着重要的作用。     

Protein and energy digestibility and gonad development of the European sea urchin Paracentrotus lividus (Lamarck) fed algal and prepared diets during spring and fall

Protein and energy are two of the main limiting factors for sea urchin growth. However, the requirement of daily protein and energy to maximize gonadal production is still unknown. Paracentrotus lividus were fed three experimental diets: Ulva lactuca, Gracilaria conferta and a prepared diet for 2 months in the fall of 1999 and spring of 2000. Sea urchins from a laboratory‐cultured population of equal age, weight and test diameter were used. Apparent digestibility coefficients (ADC%) for protein and energy, using acid‐insoluble ash as a marker, were measured for all experimental diets. Apparent digestibility coefficients for protein was high (>75%) for all diets. Energy digestibility varied among the diets and was lowest for G. conferta (50–62%). The three diets contained varying digestible protein (DP) to digestible energy (DE) ratios of 25, 26 and 12 mg kJ^?1 for U. lactuca, G. conferta and the prepared diet respectively. Digestible protein intake was similar for all treatments, but DE intake was greater for sea urchins fed the prepared diet in both seasons. As a result, the gonad production was significantly higher for urchins fed the prepared diet, suggesting that energy was limiting in the algal diets. Paracentrotus lividus spawned during the spring experiment, resulting in protein loss in all treatments. Protein loss was lowest in the sea urchins fed the prepared diet. Enhanced gonadal growth and gamete development of P. lividus resulted from the higher dietary energy content of the prepared diet.