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饲料蛋白水平对匙吻鲟幼鱼肌肉营养成分及消化酶活力的影响 总被引:3,自引:0,他引:3
配制蛋白水平34.16%、36.53%、39.10%和41.08%的4种等能半精制饲料,在水温28~32℃条件下,饲喂体质量(19.91±3.73)g的匙吻鲟45d,研究饲料蛋白水平对匙吻鲟肌肉营养成分和消化酶(酸性蛋白酶、碱性蛋白酶、α-淀粉酶和脂肪酶)活性的影响。结果显示,41.08%组体质量显著高于36.53%组,其余各组体质量差异不显著;肌肉粗蛋白含量随着饲料蛋白水平的增加而增加,各组肌肉水分、粗脂肪和粗灰分含量差异不显著;酸性蛋白酶和肝胰脏碱性蛋白酶活力随饲料蛋白水平的增加而增加,而肠道碱性蛋白酶活力随饲料蛋白水平的增加而降低;消化道α-淀粉酶活力随饲料蛋白水平的增加而降低,而肝胰脏α-淀粉酶活力表现出相反的趋势;饲料蛋白水平对消化道和肝胰脏脂肪酶活力影响不显著,各组脂肪酶活力差异不显著。试验结果表明,饲料蛋白水平对匙吻鲟肌肉粗蛋白含量、酸性蛋白酶、碱性蛋白酶和α-淀粉酶都会产生显著影响;饲料蛋白水平为39.10%比较适宜。 相似文献
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Mohsen Pourasadi Bahram Falahatkar Ghobad Azari Takami 《Aquaculture International》2009,17(4):317-321
A minimally invasive surgical technique (MIST) for the removal of ovulated eggs from Persian sturgeon Acipenser persicus was tested on broodstocks caught from the wild to determine whether it affected fecundity or hatching rates compared with
the traditional stripping method of killing and removing the eggs (commonly used in hatchery). Morphological parameters of
females, germinal vesicle (GV) position, weight of obtained egg, number of eggs/gram, fertilization rate, and percentage of
hatching during incubation were not significantly different between the MIST and traditional stripping methods. Obtained ova
were 4.8 ± 0.4 kg female−1 in the MIST and 4.6 ± 0.5 kg female−1 in traditional stripped groups, respectively; the fertilization rate was 83.4 ± 11.2% and 80.0 ± 7.2% in groups, respectively.
The results of this study showed that the minimally invasive surgical technique approach is efficient, practical, and less
stressful to Persian sturgeon broodstocks during artificial propagation than other reported egg collection procedures. 相似文献
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温度对奥尼罗非鱼受精卵孵化和仔鱼活力的影响 总被引:3,自引:0,他引:3
研究了温度对奥尼罗非鱼(Oreochromis niloticus×O.aureus)受精卵孵化和仔鱼活力的影响。在盐度为5不同温度(22、24、26、28、30、32和34℃)下,比较观察奥尼罗非鱼受精卵的培育周期、孵化周期、孵化率和畸形率。同时在以上不同温度条件下对初孵的奥尼罗非鱼仔鱼进行耐饥饿试验,测定其不投饵存活系数(Survivalactivity index,SAI)。结果表明:在温度为24~32℃,受精卵孵化率较高(84.3%~91%),温度高于34℃和低于22℃时,孵化率较低。温度与培育周期呈负相关关系,函数关系为y=0.3607x2-26.836x+553.5,R2=0.973。仔鱼生存适宜温度是24~30℃,最适的温度是24~26℃。温度为22℃时,SAI值分别为19.9,但是仔鱼发育的缓慢,部分仔鱼的身体色素一直没有出现,不适合仔鱼的培育。 相似文献
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Alfredo F. Ojanguren Felipe G. Reyes-Gavilán Rolando Rodríguez Muñoz 《Aquaculture International》1999,7(2):81-87
Three embryonic stages of Atlantic salmon (Salmo salar L.) were subjected to eight constant incubation temperatures (4, 7, 10, 12, 14, 16, 19 and 22 °C) exceeding the range usually experienced in natural conditions. A change in thermal tolerance during the embryonic and larval development was registered: pre-hatching stages showed an upper thermal limit at about 16 °C, while hatched larvae survived until 22 °C. Temperature significantly affects developmental rate, resulting in a faster development and, consequently, lower yolk weight percentage at higher temperatures. We found positive relationships between incubation temperature and body size (length and weight) in the less developed stages, in which some yolk remained, but size decreased at increasing temperatures when yolk was completely exhausted. 相似文献
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Fa-Wen Yin Yan-Fei Liu Qi Zhao Xin Zhou Liang Song 《Journal Of Aquatic Food Product Technology》2017,26(7):835-842
Krill oils (KOs) were prepared using different extraction methods (hexane and supercritical carbon dioxide), different materials (heat-dried krill powder, freeze-dried krill powder, and freeze-dried krill tail meat powder), and different standing times during hexane extraction. The fluoride concentrations in the KOs were positively correlated with the protein concentrations. Absorbents were employed to remove fluoride from KO. Activated clay achieved the highest fluoride removal rate (70.66%), followed by calcium oxide (14.49%), activated carbon (11.97%), calcium chloride (9.32%), activated alumina (0.94%), and chitosan (0.52%). Meanwhile, the protein removal rates of the above absorbents were positively correlated with the fluoride removal rates. 相似文献
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研究辣木籽(Moringaseed)去除水中余氯效果,为水净化处理实际应用提供科技支撑。用超纯水溶解含氯消毒片(有效氯含量为800~900 mg/片)制备含氯水,总余氯起始浓度分别为1、2、4 mg/L,其中游离余氯为0.94、1.94、3.91mg/L,化合余氯为0.06、0.06、0.09mg/L。每一总余氯浓度设3试验组和1对照组。其中试验组分别加入0.16、0.80、4.00g/L的辣木籽水提液50mL,对照组加入纯水50mL。计算反应时间0.5、2、4、24h各水样中游离余氯、总余氯和化合余氯的浓度。结果表明:辣木籽水提液对游离余氯去除效果明显,0.80g/L辣木籽水提液对总余氯浓度4mg/L的水有良好的净化效果,且游离余氯去除率达90%;在处理过程中,化合余氯浓度先升高后降低,升高程度与余氯浓度呈正相关性;4.00g/L水提液对较低余氯浓度水体的化合余氯去除率达99%,但处理余氯浓度高的水体时会使化合余氯含量升高。需要进一步研究的问题是在去除过程中化合余氯浓度在一段时间内增高、辣木籽净水活性成分的提取工艺和与其他净水方法协同处理废水技术等。 相似文献
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单级生物接触氧化法去除海水养殖废水中的无机氮 总被引:1,自引:0,他引:1
利用在填料上人工接种微生物组成的浸没式生物接触氧化单级处理系统对养殖废水进行净化,效果良好。在试验水体体积与处理系统体积之比约为100∶1的情况下,对氨氮、亚硝酸盐氮、硝酸盐氮起始质量浓度分别为4.0 mg/L、1.76 mg/L、800 mg/L,COD质量浓度为16.33 mg/L的养殖废水进行处理,发现处理系统中进行着强烈的硝化和反硝化作用:处理30 h,氨氮质量浓度下降并一直保持在0.1 mg/L;亚硝酸盐氮浓度48 h内,前6 h从1.76 mg/L短暂上升到2.24 mg/L,然后持续下降,最低到0.22 mg/L;对硝酸盐氮的反硝化作用能力也很强,经48 h处理,硝酸盐氮质量浓度从800 mg/L下降到180 mg/L。根据对处理过程中的水质测定,浸没式生物接触氧化单级处理试验系统具有较强的生物脱氮能力。 相似文献
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海马齿对海水养殖系统中氮、磷的移除效果研究 总被引:3,自引:0,他引:3
大量的外源性饵料和排泄物使海水养殖水体N、P以及有机物大量增加,导致水质恶化,是制约海水养殖业发展的主要因素。通过构建海马齿面积比为3∶2盐度为15的A、B 2组浮床海水养殖系统,以检验海马齿的N、P移除能力。结果显示,当海马齿处于生长启动期,A组和B组的水质指标与对照组之间无显著性差异(P>0.05);但当海马齿生长进入稳定期后,A组和B组的氨氮去除率为74%~91%和60%~91%,亚硝态氮去除率为93%~98%和71%~97%,总氮去除率为11%~25%和14%~33%,COD去除率为67%~85%和61%~81%,总磷去除率为41%~68%和35%~71%,试验组氨氮、亚硝态氮、COD和总磷浓度与对照组之间都存在显著性差异(P<0.05)。2组不同密度的海马齿浮床系统都显示了较高的N、P去除能力,表明海马齿在盐度5时能有效地吸收N、P,降低COD,减少有机物污染,改善养殖环境。 相似文献
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生态浮岛植物在富营养化养殖水体中去磷途径的初步分析 总被引:4,自引:0,他引:4
植物修复富营养化养殖水体过程中磷(P)的去除途径主要包括植物吸收、植物根系吸附、底泥吸附和还原状态下的磷挥发。为了深入探讨植物修复去磷机理,阐明植物修复富营养化养殖水体过程中磷的去向问题,分别以夏秋季(高温)和冬春季(低温)的高效除磷植物大漂和冬牧70组成的生态浮岛为研究对象,通过研究模拟条件下的富营养养殖水体生态修复系统,研究不同温度季节下生态浮岛植物在富营养养殖水体中各去磷途径对水体总磷(TP)去除量的贡献率大小。结果表明:经过20 d处理后,生态浮岛植物大漂和冬牧70对富营养化养殖水体中总磷的去除效率都较高 ,均达50%以上;在生态浮岛植物修复富营养养殖水体过程中最主要的磷去除途径都为植物吸收作用和底泥吸附作用,分别占水体中总磷去除量的23%~58%和27%~51%;其次是植物根系吸附作用,占水体中总磷去除量的13%~28%;贡献率最低的是还原状态下的磷挥发,一般低于1.5%,几乎可忽略不计。 相似文献
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邻苯二甲酸二丁酯和邻苯二甲酸二辛酯对大黄鱼受精卵及仔鱼的急性毒性效应 总被引:1,自引:0,他引:1
邻苯二甲酸二丁酯(dibutyl phthalate,DBP)和邻苯二甲酸二辛酯(dinoctyl phthalate,DOP)是一类重要的工业用有机化合物,在水环境中广泛分布,对水生生物具有一定的毒性效应。为了研究DBP和DOP对大黄鱼(Larimichthys crocea)受精卵及初孵仔鱼的急性毒性效应,开展大黄鱼幼鱼在DBP和DOP中的暴露实验。结果显示,随着DBP和DOP浓度的升高,大黄鱼受精卵孵化率呈现逐步降低的趋势,死亡率、畸形率则呈现逐步升高的趋势。DBP和DOP暴露对大黄鱼初孵仔鱼均产生一定的致死效应,DBP和DOP对大黄鱼仔鱼的96 h半致死浓度分别为5.23 mg·L^-1 和6.57 mg·L^-1 。结果表明,DBP和DOP对大黄鱼鱼卵及初孵仔鱼均具有高毒毒性。DBP和DOP对水生生物的慢性毒性需要进一步关注。 相似文献
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诱导鲤雌核发育时精子入卵的扫描电镜观察 总被引:3,自引:0,他引:3
以雌核发育性成熟鲤(Cyprinuscarpio)卵子和经紫外线照射处理遗传失活的鲫鱼(Carassiusauratus)精子为材料,在再次诱导其雌核发育时,通过扫描电镜和光学显微镜对比观察诱导组和正常受精组精子入卵的情况及鲤鱼成熟卵受精过程中精孔区的外部形态变化。结果表明,无论试验组或对照组在受精后2s精子就能迅速到达精孔区。精子入孔后,受精孔便被絮状物质堵塞;受精后35~40s壳膜表面开始模糊;60s后,精孔区絮状物及精子均消失。 相似文献
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Two kinds of specific chicken egg yolk immunoglobulins (IgYs), IgY‐WSSV and IgY‐VP28, were, respectively, raised against the 2 mM binary ethylenimine (BEI)‐inactivated white spot syndrome virus (WSSV) and a principal envelope protein VP28. The activity of purified specific IgYs was stable under the conditions of 20–70 °C, pH 3.0–10.0 and 0–700 g L?1 sucrose solution. In the neutralization assay, these high‐affinity IgY antibodies can specifically bind with the virus particles to protect shrimp (Fenneropenaeus chinensis) against WSSV infection. After oral delivery for 20 days, the IgY‐WSSV exerted a higher protection effect (RPS: 71.5%) than IgY‐VP28 (RPS: 63.7%). Moreover, an increase in RPS (79.2%) was found on addition of IgY‐WSSV:VP28 (0.1% IgY‐VP28 plus 0.2% IgY‐WSSV). This may indicate that neutralization of WSSV refers to the multiple‐hit model. By time‐course study of the levels of the specific IgYs in vivo, the data showed that the titre was enhanced to a relatively high level (P/N=8.35±0.45) at 3 days post administration, declined slightly (P/N=7.13±1.01) at 7 days post administration and then remained stable for further investigation. The stable antibody level potentially contributes towards blocking a large number of WSSV particles from entering and infecting on the major tissues at the early and late stages after challenge in shrimp. 相似文献
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采用上流式和下流式曝气生物滤池处理凡纳滨对虾(Litopenaeus vannamei)养殖污水,连续进行30 d,分析出水水质,并观察系统运行情况和装置污染状况。研究了养殖污水中化学需氧量、氨氮、硝酸盐氮、亚硝酸盐氮、无机氮及活性磷酸盐6项指标的去除效果。实验结果表明:从养殖污水主要污染物指标的去除效果和稳定性上看,上流式优于下流式曝气生物滤池。在系统进水化学需氧量质量浓度为7.62~8.20 mg/L、氨氮质量浓度为0.62~0.65 mg/L、硝酸盐氮质量浓度为0.54~0.59 mg/L、亚硝酸盐氮质量浓度为0.23~0.27 mg/L、无机氮质量浓度为1.40~1.47 mg/L、活性磷酸盐质量浓度为0.24~0.29 mg/L,水温为25℃~30℃时,上流式曝气生物滤池对养殖污水中6项指标的去除率分别为:45.2%、88.9%、58.5%、78.8%、75.3%和25.1%。可见,对氨氮的去除效果最佳,亚硝酸盐氮和无机氮次之,化学需氧量和硝酸盐氮的去除效果较差,活性磷酸盐去除率最低。 相似文献