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Effects of dietary supplementation with freeze‐dried powder of Ampithoe sp. on the growth performance,energy metabolism,and ammonia‐nitrogen tolerance of the Pacific white shrimp,Litopenaeus vannamei 
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下载免费PDF全文 This study evaluated the influence of dietary supplementation with freeze‐dried powder of Ampithoe sp. (FDPA) on the growth, energy metabolism, and resistance to ammonia‐nitrogen stress in Litopenaeus vannamei. There were four treatment groups: a 0% group (no FDPA addition), a 33% group, a 66% group (33% and 66% of the shrimp diet, respectively, replaced with FDPA), and a 100% group (only FDPA). The results of this study suggested a positive effect of FDPA supplementation on shrimp survival: the supplemented groups had significantly higher survival than the 0% group (p < 0.05). The body length, body weight, and specific growth rate (SGR) of the 33% group were higher than those of the other groups and were significantly higher than that of the 100% group (p < 0.05). FDPA feeding had a negative effect on carbohydrate metabolism pathways and energy consumption due to decreases in pyruvate kinase (PK), phosphofructokinase (PFK), succinate dehydrogenase (SDH), lactic dehydrogenase (LDH), and respiratory electron transport system (ETS) activity in shrimp fed FDPA during the culture period. The shrimp in the 33% group exhibited good resistance to ammonia‐nitrogen stress. Additionally, the glycolysis pathway and energy consumption of shrimp in the 33% group were enhanced during the ammonia‐nitrogen stress period. Consequently, it was inferred that FDPA supplementation could improve the resistance of shrimp to ammonia‐nitrogen stress (in the 33% group), which might be related to the effects of the supplement on energy metabolism pathways, particularly in terms of enhancing glycolysis to provide sufficient energy for the stress response. 相似文献
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以强壮藻钩虾(以下简称钩虾)作为中国明对虾和日本囊对虾的天然饵料,以对虾人工配合饲料为对照研究钩虾对中国明对虾和日本囊对虾生长和抗病力的影响。对两种规格的中国明对虾[体质量分别为(0.33±0.0204)g和(2.07±0.184)g,分别记为SF组和MF组]和日本囊对虾[体质量为(0.25±0.018 1)g,记为SM组]分别投喂人工配合饲料和钩虾,养殖35 d。结果显示:(1)与人工配合饲料相比钩虾可以提高MF组和SM组对虾的特定生长率和SM组对虾的成活率;(2)钩虾可以显著提高SF组和SM组对虾血细胞总数(P<0.05);(3)钩虾可以显著提高3组对虾血清总蛋白含量(P<0.05)及SF组和SM组血蓝蛋白含量(P<0.05);(4)钩虾可以显著提高日本囊对虾溶菌酶活力(P<0.05);(5)钩虾可以显著提高FM组和SM组对虾酚氧化酶活力和超氧化物歧化酶活力(P<0.05);(6)钩虾可以显著性提高SF组和SM组对虾血清过氧化物酶相对活力(P<0.05);(7)对虾健康指标总得分与其感染WSSV后的100%致死时间关系密切,两者之间呈现一定的线性关系(R2=0.948 9)。研究结果表明,钩虾与对虾人工配合饲料相比可以促进中国明对虾和日本囊对虾的生长及提高对虾抗病力。 相似文献
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通过比较,研究了粗状假丝酵母诱变株产脂肪酶催化水解不同底物的相对活力,包括低级酯、脂肪酸甘油酯和天然油脂。并对粗状假丝酵母产脂肪酶催化水解猪油反应中的pH值、温度、时间、加酶量、乳化剂用量和Ca2+浓度等因素进行了研究,得出pH值为7.5、温度为45℃、水解反应时间为72h、加8ml粗酶液、2%油的乳化剂、Ca2+浓度为75mmol/l时,猪油有最佳水解率。通过对该酶反应动力学进行研究得出其水解反应的米氏常数Km为12.25×10-3mol/l和最大反应速率Vmax为11.14μmol/min。 相似文献
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为了解温度和光照对强壮硬毛藻(Chaetomorpha valida)吸收营养盐效果的影响,探索其达到最佳吸收效果的环境条件,本文研究了该藻在不同温度(5、15、25℃)和光照[90 000、180 000、270 000μmol photons/(m2·s)]条件下对海水中常见营养盐成分的吸收效果。结果显示,强壮硬毛藻在5℃以上和90 000μmol photons/(m2·s)光照强度以上对水体中的NH4+-N、NO2--N和PO43--P都有较好的吸收效果,但温度和光照对强壮硬毛藻吸收营养盐均有显著影响,在设定范围内,营养盐吸收速率与温度和光照强度均呈正相关关系。极差分析结果显示,温度的影响大于光照强度的影响。方差分析结果显示,光照强度和温度的主效应都极显著,而且具有叠加效应,吸收率最高的条件为25℃/270 000μmol photons/(m2·s)组合,该条件下,NH4... 相似文献
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在实验室培养条件下,以采自辽宁大连的强壮硬毛藻为试验对象,对其在不同盐度和透明度条件下的生长发育情况进行研究。设置10、20、30、40、50 5个盐度组,设置40、60、80、120、140 cm 5个透明度组,试验采用单因素方差分析,只改变其中一个环境因子,其余环境因子不变,对强壮硬毛藻进行分组培养,然后对其日特定生长率进行测定与分析。试验结果显示,盐度和透明度对强壮硬毛藻的生长发育均有一定影响。藻体生长的适宜盐度为30~40,其中在盐度为30时,藻体的日特定生长速率最高,达65%,随盐度的继续升高,强壮硬毛藻的日特定生长率呈下降趋势,在盐度达到50时,藻体出现死亡现象;在透明度高于120 cm时,藻体生长状况良好,透明度低于120 cm时,藻体的生长由于水下光照条件的限制而受到了明显的抑制。本试验表明,强壮硬毛藻为广盐性种,且高盐、低透明度条件对强壮硬毛藻的生长发育有一定抑制作用,为强壮硬毛藻的防治提供了一定理论依据。 相似文献
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Effects of Dietary Ampitheoe sp. Powder on Growth and Lipid Contents of Litopenaeus vannamei北大核心CSCD
This experiment was conducted to investigate the effects of dietary Ampitheoe sp. powder on the growth and the contents of astaxanthin, triglyceride (TG), total cholesterol (TCHO) and fatty acids of Litopenaeus vannamei. A total of approximately 6 777 L. vannamei with an initial body weight of (1. 80 ± 0.72) g were randomly divided into 3 groups, and there were 3 replicates (753 shrimp per replicate) in each group. Those shrimp fed diets containing 0 (D0 group), 8. 25% (D8. 25 group) and 33% (D33. 00 group) Ampitheoe sp. powder, respectively. The feeding trial lasted for 40 days. The results showed as follows: 1) the final body weight, weight gain rate, specific growth rate, yield and survival rate in D33.00 group were significantly higher than those in D0 group (P <0.05), whereas the feed conversion ratio was significantly lower than that in D0 group (P <0.05) . However, there was no significant difference between D33.00 group and the D8. 25 group in those indexes (P >0.05) . 2) The astaxanthin content in carapace, hepatopancreas and muscle of L. vannamei in D8.25 and D33. 00 groups was significantly higher than that in D0 group (P < 0. 05); that in D33.00 group was significantly higher than that in D8. 25 group (P < 0. 05) . 3) TG content in haemolymph, hepatopancreas and muscle in D8. 25 and D33. 00 groups was significantly lower than that in D0 group (P < 0.05); the TCHO content in hepatopancreas in D8. 25 group was significantly higher than that in D0 and D33.00 groups (P <0.05); TCHO content in muscle in D33.00 group was significantly higher than that in D0 group (P <0.05) . 4) The contents of eicosapentaenoic acid (EPA) and arachidonic acid (AA) in hepatopancreas in D33.00 group were significantly higher than those in D0 group (P <0.05) . The EPA content in muscle in D33.00 group was significantly higher than that in D0 group (P < 0. 05) . In conclusion, adding Ampitheoe sp. powder into the diet can improve the growth performance, the contents of astaxanthin, EPA and AA in L. vannamei, and affect the accumulation of TG and TCHO, which can be used as a functional diet in aquaculture. Considering the cost, the supplementation level of 8. 25% Ampitheoe sp. powder is more appropriate. © 2023 Chinese Journal of Pediatric Surgery. All rights reserved. 相似文献
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