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91.
Effects of dopamine injection on the hemocyte count, phenoloxidase activity, serine proteinase activity, proteinase in-hibitor activity and α2-macroglobulin-like activity in L. vannamei were studied. Results showed that dopamine injection resulted in a significant effect on the parameters measured (P < 0.05), while no significant difference was observed in the control group (0.85% NaCl). In the experimental groups,the hemocyte count reached the minimum in 3 h;granular and semi-granular cells became stable after 12 h and hyaline cells and the total hemocyte count became stable after 18 h. Phenoloxidase activity reached the minimum in 6 h, and then became stable after 9 h. Serine protease activity and proteinase inhibitor activity reached the minimum in 3 h, and α2-macro-globulin-like activity reached the maximum in 3 h,and all the three parameters became stable after 12 h. The results suggest that the activating mechanisms of the proPO system triggered by dopamine are different from those triggered by invasive agents or sponta-neously activated under a normal physical condition. 相似文献
92.
Hemocyte counts and phenoloxidase(PO)activity were examined after hemolymph being incubated in dopamine(DA),noradrenaline(NE)and serotonin(5-HT).Results showed that all the three biogenic amines(BAs)had a significant impact on total hemocyte count(THC),differential hemocyte count(DHC),and intracelluar and extracelluar phenoloxidase(PO)activity.Among these Bas,DA had the strongest effect on the above parameters,whereas 5-HT had the least effect.Preincubation with D1 receptor antagonist SCH23390,D2 receptor a... 相似文献
93.
复合中草药对凡纳滨对虾生长和消化酶活力的影响 总被引：6，自引：0，他引：6
选用豆粕-鱼粉型饲料,分别添加0.0、0.5、1.0、2.0和4.0g·kg-1的复合中草药(CTMs),检测其促生长作用及其对消化酶活性的影响。结果显示,生长第1阶段:2组特殊生长率(SGR)、饲料系数(FCR)和蛋白质效率比(PER)均显著大于对照组(P<0.05),与余下三组差异不显著(P>0.05);2组、3组体长增长率(LGR)与对照组差异显著(P<0.05);2组、3组存活率与5组差异显著(P<0.05)、与对照组差异极显著(P<0.01);各组间相对增重率(RWG)和日生长速度(AGR)差异不显著(P>0.05)。生长第2阶段:2组AGR与对照组差异极显著(P<0.01),与其他三组差异不显著(P>0.05);2组、3组FCR分别与对照组差异显著(P<0.05)和差异极显著(P<0.01);2组、3组PER与对照组差异显著(P<0.05);和对照组相比,4组成活率提高显著(P<0.05),2组和3组提高极显著(P<0.01);RWG和LGR变化规律与第一阶段相似;各组间SGR无显著差异(P>0.05)。CTMs提高消化酶活性,对蛋白酶活性影响明显。 相似文献
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95.
对凡纳滨对虾注射浓度为1×105、1×106、1×107mL-1的溶藻弧菌悬液,在注射后4、12、24、48、72和120 h于腹血窦取血,测定其血清中一氧化氮(NO)、丙二醛(MDA)含量,以及一氧化氮合酶(NOS)、超氧化物岐化酶(SOD)活力。结果表明,注射溶藻弧菌后,凡纳滨对虾血清中NO含量及NOS活力显著高于对照组,且NOS活力最大值出现时间较NO早;而SOD活力先升高后下降,MDA含量在SOD活力开始下降后逐渐升高,说明一氧化氮系统对凡纳滨对虾感染的溶藻弧菌有清除作用,并能在一定程度上对损伤过程中生成的氧自由基产生作用。 相似文献
96.
《青岛海洋大学学报(英文版)》2014,(2):311-320
An 8 weeks feeding experiment was conducted to determine the effect of dietary potassium on the growth and physio-logical acclimation of Pacific white shrimp （Litopenaeus vannamei） reared in diluted seawater （salinity 4）. Six semi-purified practical diets containing 0.59, 0.96, 1.26, 1.48, 1.74, and 2.17 g potassium K＋ per 100 g diet were formulated, respectively. The survival and feed conversion rate did not show significant difference among groups of shrimps given these diets （P〉0.05）. The shrimps fed the diets containing 0.96-1.48 g K＋ per 100g diet gained the highest weight, specific growth rate, and protein efficiency ratio. Their ammonium-N excretion rate as well as hemolymph concentration of Na＋ and C1- were significantly lower than those of the control （P〈0.05）, but a reverse trend was observed for their gill Na＋/K＋-ATPase. Moreover, the shrimps fed with 1.48 g K＋ per 100 g diet were the highest in hemolymph urea level, and the phenoloxidase and lysozyme activities were significantly higher than those of the control （P〈0.05）. The growth and physiological response of the test shrimps suggested that diet containing 1.48 g K＋ per 100 g diet improved the growth of L. vannamei in low-salinity seawater, and enhanced the physiological acclimation of the organism. 相似文献
97.
LIU Hongyu ZHANG Xinjie TAN Beiping LIN Yingbo CHI Shuyan DONG Xiaohui and YANG Qihui 《中国海洋大学学报(英文版)》2014,13(2):311-320
An 8 weeks feeding experiment was conducted to determine the effect of dietary potassium on the growth and physiological acclimation of Pacific white shrimp(Litopenaeus vannamei) reared in diluted seawater(salinity 4). Six semi-purified practical diets containing 0.59, 0.96, 1.26, 1.48, 1.74, and 2.17+ g potassium K per 100 g diet were formulated, respectively. The survival and feed conversion rate did not show significant difference among groups of shrimps given these diets(P0.05). The shrimps fed the diets containing 0.96-1.48 g K+ per 100 g diet gained the highest weight, specific growth rate, and protein efficiency ratio. Their ammonium-N excretion rate as well as hemolymph concentration of Na+ and Cl- were significantly lower than those of the control(P0.05), but a reverse trend was observed for their gill Na+/K+-ATPase. Moreover, the shrimps fed with 1.48 g K+ per 100 g diet were the highest in hemolymph urea level, and the phenoloxidase and lysozyme activities were significantly higher than those of the control(P0.05). The growth and physiological response of the test shrimps suggested that diet containing 1.48 g K+ per 100 g diet improved the growth of L. vannamei in low-salinity seawater, and enhanced the physiological acclimation of the organism. 相似文献
98.
Litopenaeus vannamei, a euryhaline species, can be cultured at a wide range of salinities. The emergence of freshwater pond-culture of L. vannamei is an important prelude to the continued development of shrimp culture in China. In this study, we compared the respiratory metabolism of juvenile L. vannamei cultured in freshwater and saltwater by measuring their oxygen consumption rate (OCR), ammonium-type nitrogen excretion rate (AER) and pyruvate kinase (PK) and lactate dehydrogenase (LDH) activities at different molting stages in order to physiecologically characterize juvenile L. vannamei under freshwater conditions. The results showed that OCR was significantly higher in saltwater than in freshwater at all stages of molting cycle. However, variation of OCR among molting stages in saltwater was similar with that in freshwater, and the highest OCR was observed at post-molting stage. At all stages of molting cycle, AER was significantly higher in freshwater than in saltwater, and the highest was observed at post-molting stage. The activity of PK was significantly higher in saltwater than in freshwater. Conversely, the activity of LDH was higher in freshwater than in saltwater in general. Significant variation of PK and LDH activities in molting cycle was observed in saltwater and freshwater. The results indicated that aerobic metabolism of juvenile L. vannamei was more active in saltwater than in freshwater; while its protein metabolism was more active in freshwater than in saltwater. 相似文献
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100.
In this study, we investigated the effects of low salinity(26 and 21)on the prophenoloxidase(proPO)system and related defence parameters in the shrimp Litopenaeus vannamei. The results showed that low salinity induced a significant increase of dopamine(DA)concentration in haemolymph at 6h of the experiment; on the other hand, total haemocyte count(THC), differential haemocyte count(DHC)and PO activity decreased over time to the lowest level at 24 h and remained low thereafter. Serine Protease(SP)and Proteinase Inhibitor(PI)activity in the two lower salinity treatments decreased to the lowest level at 12 and 24h, respectively, and both recovered to the control level at 72 h. In contrast, α2-macroglobulin(α2M)activity in the two lower salinity treatments peaked at 24h and then decreased to the control level at 72h. Therefore, it may be concluded that stress-induced DA plays an important temporary role in neurotransmission and causes immune response in L. Vannamei in adapting to salinity changes. 相似文献