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71.
Serotonin induces ovarian maturation in giant freshwater prawn broodstock, Macrobrachium rosenbergii de Man 总被引:1,自引:0,他引:1
Prasert Meeratana Boonsirm Withyachumnarnkul Praneet Damrongphol Kanokphan Wongprasert Anchalee Suseangtham Prasert Sobhon 《Aquaculture (Amsterdam, Netherlands)》2006,260(1-4):315-325
This study investigated the effects of serotonin (5-hydroxytryptamine or 5HT) on ovarian development in Macrobrachium rosenbergii de Man. Adult female prawns at the ovarian stage I (spent) were injected with 5HT at 1, 5, 10, 20 and 50 μg g− 1 body weight (BW) intramuscularly on days 0, 5 and 10, and sacrificed on day 15. The doses as related to the effect could be categorized into three levels: low (1 and 5 μg g− 1 BW of 5HT), medium (10 and 20 μg g− 1 BW of 5HT) and high (50 μg g− 1 BW of 5HT). The low-dose, especially at 1 μg g− 1 BW, caused prawns to exhibit a significant increase in ovarian index (ovarian weight/body weight × 100) (5.79 ± 0.09%) as compared to the control (1.49%). The ovaries of most of these prawns could develop to stage IV (mature) and contained synchronously mature oocytes while most of the control ovaries remained at stage I and II (proliferative), and contained only oogonia to previtellogenic (Oc1, Oc2) and early vitellogenic oocytes (Oc3). The medium- and high-dose treated prawns exhibited ovaries that could reach stages III and IV and contained various types of oocytes of different maturity. Pretreatment with 5HT receptor antagonist, cyproheptadine (CYP), at 10 μg g− 1 BW before 5HT injection significantly suppressed the effect of 5HT. Intramuscular injection of the 5HT-primed thoracic ganglion culture medium into CYP-pretreated prawns resulted in the increase of ovarian index about 5–6 times more than in the control, and in the groups injected with 5HT-primed media from muscle strip, eyestalk and brain. The ovaries of most prawn could develop up to stage IV and contained synchronously developed vitellogenic (Oc4) and mature oocytes (Oc5). These findings suggest that 5HT indirectly induces ovarian development and oocytes maturation in M. rosenbergii, probably via a putative ovarian stimulating factor released from the thoracic ganglia. 相似文献
72.
还原型谷胱甘肽对大菱鲆生长及抗氧化能力的影响 总被引:1,自引:0,他引:1
在基础饲料中添加不同剂量的还原型谷胱甘肽,添加量分别为0、100、200、400、600 mg/kg,投喂初始体质量为(23.08±0.09) g的大菱鲆,8周后测定还原型谷胱甘肽对大菱鲆生长及抗氧化能力的影响。试验结果表明,饲料中还原型谷胱甘肽添加量为200 mg/kg时,大菱鲆的质量增加率和特定生长率显著高于其他组(P<0.05)。饲料中添加还原型谷胱甘肽对大菱鲆肝脏中丙二醛含量、总抗氧化能力、超氧化物歧化酶活力、谷胱甘肽过氧化物酶活力均无显著影响(P>0.05)。随着还原型谷胱甘肽添加量的增加,大菱鲆肝脏中丙二醛含量呈先降后升的趋势,对照组最高,200 mg/kg试验组最低;大菱鲆肝脏中总抗氧化能力、超氧化物歧化酶活力和谷胱甘肽过氧化物酶活力均呈先升后降的趋势,200 mg/kg试验组最高。200 mg/kg试验组和400 mg/kg试验组大菱鲆肝脏中还原型谷胱甘肽含量显著高于对照组(P<0.05)。200 mg/kg试验组大菱鲆肝脏中谷胱甘肽硫转移酶活力和谷胱甘肽还原酶活力显著低于对照组(P<0.05)。根据回归分析,确定大菱鲆饲料中还原型谷胱甘肽的最适添加量为189.70 mg/kg。 相似文献
73.
Abstract – We have studied the population dynamics and reproductive biology of perch ( Perca fluviatilis L.) from five neighbouring lakes in Norway. The lakes vary in water quality, varying from strongly acidified (pH≤5.0) to not acidified (pH≥6.0). Estimated annual survival rates did not differ among populations. There was no strong relationship between age at maturity in female perch and acidification. However, age at maturity was lower for female perch from the most acidic lake ( c . 2 years) compared with perch in the four other lakes (2.5–3.5 years). There was no relationship between acidification level and size-adjusted egg size, fecundity or reproductive investment (Gonadosomatic index – GSI). Perch in the most acidified lake showed large variation in egg size, the lowest length-specific fecundity, the highest GSI, and the lowest age at maturity. Environmental stress, such as acidification, induces a number of changes to a lake community. It is therefore difficult to predict how acidification will influence the population dynamics and reproductive biology of a perch population. 相似文献
74.
东海北部近海棘头梅童鱼食物组成的季节变化及随发育的变化 总被引:4,自引:0,他引:4
根据2006年7月~2008年12月采集于东海北部近海的棘头梅童鱼(Collichthys lucidus)样品,共测定体长在23~157 mm范围内的棘头梅童鱼474 ind,应用卡方检验和聚类分析等方法,对棘头梅童鱼食物组成的季节变化及随个体发育的变化进行了分析。结果显示:东海北部近海棘头梅童鱼的食物种类夏季出现较多,春季出现较少;91~110 mm体长组出现较多,≤50 mm体长组和>130 mm体长组出现较少。食物多样性指数春季较高,秋季较低;≤50 mm体长组较低,>130 mm体长组较高,食物多样性指数随体长的增加而升高。卡方检验显示,棘头梅童鱼主要食物种类宽尾刺糠虾(Acanthomysis latiscauda)、中国毛虾(Aceteschinensis)、七星底灯鱼(Myctophum pterotum)和中华哲水蚤(Calanus sinicus)的出现频率有极显著的季节变化,中华假磷虾(Pseudeuphausia sinica)的出现频率有显著的季节变化;宽尾刺糠虾和七星底灯鱼的出现频率随体长的变化极显著,而中国毛虾、中华假磷虾和中华哲水蚤的出现频率随体长的变化不显著。聚类分析结果表明,棘头梅童鱼春冬季、夏季和秋季三个时期的食物组成差异显著;体长聚类分两组,即体长>70 mm和≤70mm之间食物组成有明显差异。通过分析发现:东海北部近海棘头梅童鱼食物的季节变化与该海域饵料生物的季节变化密切相关;食物组成随发育的变化符合"最佳摄食理论",其饵料生物种类和大小随棘头梅童鱼体长的增加发生了显著的变化。 相似文献
75.
76.
北部湾多齿蛇鲻摄食习性及随生长发育的变化 总被引:2,自引:1,他引:2
2008年10月至2009年9月,对北部湾多齿蛇鲻逐月采样共749尾(实胃数408个),通过胃含物分析法研究其摄食习性及随生长发育的变化。结果表明,北部湾多齿蛇鲻捕食种类包括鱼类、头足类以及虾类等饵料生物,其中可鉴定出的鱼类种类有17种。以相对重要性指数百分比为指标,鱼类为最主要饵料(98.8%),其中优势饵料种类有蓝圆鲹(34.9%)、少鳞犀鳕(26.6%)、长颌棱鳀(4.30%)和条鲾(2.5%)。多齿蛇鲻摄食强度、饱满指数和成熟系数的月份差异十分显著,而以Brillouin指数表征的各月份营养多样性则无显著差异。一年中呈现3个产卵高峰期(3-4月、6月及11月),产卵期间摄食强度没有降低,仍然强烈索饵。随着体长的增长,北部湾多齿蛇鲻饵料生物个数变化较小,但平均单个饵料生物质量却明显增加。聚类分析表明,北部湾多齿蛇鲻各体长组间食物组成相近,其中136~255mm各体长组相似性系数均大于60%。 相似文献
77.
日本沼虾饲料最适蛋白质、脂肪含量及能量蛋白比的研究 总被引:16,自引:2,他引:16
本文研究了日本沼虾(Macrobrachium nipponense)饲料的最适蛋白质含量、脂肪含量及能量蛋白比。试验用饲料由酪蛋白、糊精、混合油、复合维生素和无机盐混合物等组成。本试验用的日本沼虾体重为 1.77±0.23克,试验期间水温为 21—25℃。用增重率、饲料系数和肝胰脏α-淀粉酶活力等作为评价指标。试验结果表明:日本沼虾配合饲料适宜蛋白质含量为 36.8—42.27%,适宜脂肪含量为6—12%。当配合饲料的蛋内质含量在适宜范围内,饲料能量蛋白比(C/P)为8千卡/克蛋白左右,每公斤配合饲料的总能量为3006—3561千卡是最为适宜的。当饲料总能量在一定范围内,随着饲料碳水化合物含量的增加,肝胰脏α-淀粉酶活力增强。 相似文献
78.
Régis Moreau Sadasivam J. Kaushik Konrad Dabrowski 《Fish physiology and biochemistry》1996,15(5):431-438
A study was conducted to evaluate tissue storage and mobilisation of L-ascorbic acid (AA) in the Siberian sturgeon (Acipenser baeri) fed three different experimental diets. The three treatments consisted of a diet devoid of vitamin C (diet A0) and two diets supplemented with equivalent of 300 mg AA kg–1 in the form of either silicone-coated ascorbic acid (diet SC) or of ascorbyl-2-polyphosphate (diet AP). During the first phase (4 months) of the trial, six batches of 130 Siberian sturgeon (initial body weight: 25.5±0.5 g) each were fed one of the three diets in duplicate. During the second phase (3 months), fish from groups SC and AP were switched to diet A0 and those fed diet A0 during the first phase were switched to diet SC. Irrespective of the dietary treatment, growth rates were not significantly different from each other. At the end of phase I, in all tissues studied, total ascorbic acid (TAA) concentrations were higher in Siberian sturgeon fed diet AP than in the other two groups. During phase II, tissue ascorbate depletion was also higher in the AP group than in the other two groups. Transfer of the AA-free diet fed group onto a diet supplemented with 300 mg AA kg–1 (diet SC) led to a slight increase in the TAA concentrations in all tissues. Blood plasma tyrosine concentrations were not significantly different between the three groups. Whole-body collagen levels were affected by dietary AA levels or forms at the end of phase I; the differences were not significant at the end of phase II. Muscle collagen levels were slightly affected. L-Gulonolactone oxidase activity was found in the kidney of Siberian sturgeon, but not in the liver. The ascorbyl-2-polyphosphate appears to be either better utilised by Siberian sturgeon, like in many other teleosts, or more stable than the silicone-coated AA during food processing and storage. Presence of L-gulonolactone oxidase activity in Siberian sturgeon kidney combined with the absence of gross scorbutic signs in AA-free diet fed groups expressing very good growth rates suggested no need of dietary AA byA. baeri. 相似文献
79.
黄颡鱼(Pelteobagrus fulvidraco)的营养学研究主要体现在食性分析、肌肉营养成份的测定等基础研究上,而营养需求上的研究主要体现在配合饲料配方上的饲养试验,对于确定某种营养素需要量的研究报道较少。本文综述了黄颡鱼对蛋白质、脂类、碳水化合物、维生素及无机盐的需要量。黄颡鱼配合饲料中蛋白质的适宜含量(稚幼鱼)为39%~45%、(成鱼)为34%~38%,脂肪的适宜含量为7%~9%,碳水化合物的适宜含量为20%~23%、粗纤维的适宜含量为5%~6%,无机盐的适宜含量为1%~2.5%。 相似文献
80.
G F Arcos A M Ibarra C Vazquez-Boucard E Palacios & I S Racotta 《Aquaculture Research》2003,34(9):749-755
The present study analyses some biochemical variables in haemolymph proposed as predictive indicators of the maturation capability following eyestalk ablation. Haemolymph of captive females was obtained before and 8 days after eyestalk ablation, and levels of haemocyanin, total proteins, glucose, lactate, cholesterol, triacylglycerides and vitellogenin were determined. Biochemical variables were also analysed in the hepatopancreas at the end of the experiment. Females were grouped as immature (previtellogenic stage) and mature (vitellogenic and cortical stages) based on histological analysis done 8 days after eyestalk ablation. To analyse haemolymph variables before eyestalk ablation in relation to maturation capability, immature females were classified as those with a low maturation capability and mature females as those with a high maturation capability. Females of high maturation capability had significantly higher vitellogenin levels before eyestalk ablation than females of low maturation capability. No significant differences were found for the other biochemical variables. Vitellogenin was also higher in mature than in immature females at the end of the experiment. These results indicate that vitellogenin levels in haemolymph could be used as possible predictive criteria of maturation capability, possibly because they reflect the degree of ovarian development at the time of eyestalk ablation. 相似文献