共查询到19条相似文献，搜索用时 250 毫秒
1.
《渔业科学进展》2016,(2)
为了研究零换水条件下团头鲂(Megalobrama amblycephala)养殖水体生物絮团形成所需的适合的碳氮比(C/N),以及不同C/N形成的生物絮团对团头鲂生长、消化酶活性和非特异性免疫力的影响,本实验设计4个不同C/N实验组,包括投喂基础饲料(C/N=8∶1)的对照组,在基础饲料上添加葡萄糖的处理组,其中将处理组的C/N分别调整为12∶1(C/N12)、16∶1(C/N16)和20∶1(C/N20)。结果显示,C/N16和C/N20处理组中团头鲂的增重率和特定生长率显著高于对照组(P0.05),而饲料系数显著低于对照组(P0.05);C/N16和C/N20处理组中团头鲂肠道的蛋白酶活性和淀粉酶活性显著高于对照组(P0.05);而各实验组中团头鲂肠道的脂肪酶活性没有显著性差异;C/N16和C/N20处理组中团头鲂肝脏超氧化物歧化酶、碱性磷酸酶和溶菌酶活性显著高于对照组(P0.05)。研究表明,生物絮团技术应用于团头鲂养殖适宜的C/N应不低于16,该条件下形成的生物絮团能有效提高团头鲂生长、消化酶和免疫相关酶活性。 相似文献
2.
不同C/N对草鱼池生物絮团的形成及水质的影响研究 总被引：1，自引：1，他引：0
为了研究草鱼池生物絮团形成所需的适合C/N,实验分析不同C/N水平对水泥池中生物絮团的形成、水质及草鱼生长的影响。对照组投喂基础饲料(C/N为10.8∶1),实验组在基础饲料上添加葡萄糖,控制C/N分别为15∶1、20∶1和25∶1。结果显示,当C/N≥15时,形成的生物絮团可以有效的调节水质,降低水体中的氨氮、亚硝酸盐氮水平;各组的生物絮团体积指数(FVI)随养殖时间逐步增加,在第14天趋于稳定;随着C/N增高,尽管实验组水体中形成的生物絮团粗蛋白含量显著高于对照组(P<0.05),但是草鱼生长却呈下降趋势。综合而言,生物絮团技术应用于草鱼养殖适宜的C/N为15,该比值能促进生物絮团的形成,并能有效降低水中的氨氮、亚硝酸盐氮水平。 相似文献
3.
为探究添加不同碳源物质所形成的生物絮团对团头鲂鱼种生长、消化酶以及抗氧化酶活性的影响,设计5个不同碳源物质的添加组[淀粉组、葡萄糖组、蔗糖组、甜蜜素组和复合碳源组(葡萄糖∶淀粉=1∶1)],其中淀粉组为对照组,每个碳源添加组设置3个重复。每个水泥池投放团头鲂鱼种20尾,初始体质量为(36.74±0.82)g,实验期为8周。结果发现:(1)形成的生物絮团可以有效地调节水质,降低水体中的氨氮和亚硝酸盐氮水平;(2)与对照组相比,葡萄糖组团头鲂鱼种的鱼体末质量显著提高23.1%,增重率显著提高39.4%,特定生长率也显著提高23.6%,饲料系数显著降低28.1%,但存活率并没有显著差异;(3)肠道组织光镜观察表明,团头鲂鱼种肠道单层柱状上皮附近存在未消化的生物絮团;(4)添加不同碳源形成的生物絮团对团头鲂鱼种体成分没有显著的影响;(5)复合碳源组的肠道总蛋白酶的活性(3.64±0.53)U/mg显著高于对照组275.3%,淀粉酶活性显著高于对照组(淀粉组)289.2%、葡萄糖组166.7%和蔗糖组860%;(6)葡萄糖组的团头鲂超氧化物歧化酶(SOD)活性为(238.67±13.63)U/mg,显著高于对照组的SOD活性72.5%,葡萄糖组团头鲂的过氧化氢酶(CAT)酶活性为(192.31±17.06)U/mg,显著高于对照组的CAT活性40.4%,与对照组的丙二醛(MDA)水平相比,葡萄糖组、蔗糖组、甜蜜素组和复合碳源组分别显著降低了69.0%、59.7%、38%.0和48.8%。研究表明,水体中添加葡萄糖为碳源能显著提高团头鲂鱼种的生长性能和抗氧化水平,并有效改善水质。 相似文献
4.
为探究零换水养殖水体中饲料蛋白水平对团头鲂(Megalobrama amblycephala)幼鱼生长、消化酶活力和血清生化指标的影响,实验设计投喂4个不同蛋白水平的生物絮团试验组(BF-20%、BF-25%、BF-30%、BF-35%)以及1个投喂35%蛋白的循环水对照组,每个处理组设置3重复,每个养殖桶放养初始体重为(6.06±0.01)g团头鲂幼鱼25尾,养殖周期为6周。结果表明:(1)形成的生物絮团可以有效地调节水质,降低水体中的氨氮、硝酸盐氮和亚硝酸盐氮水平;(2)BF-30%和BF-35%组和对照组的终末体重、增重率和饲料系数差异不显著(P0.05),但其显著高于BF-20%组(P0.05),各处理组间的存活率没有显著性差异(P0.05);(3)BF-25%组、BF-30%组和BF-35%组的肠道、肝脏超氧化物歧化酶和谷胱甘肽过氧化物酶活性显著高于对照组和BF-20%组(P0.05),而BF-20%组的肝脏丙二醛含量显著高于其他处理组(P0.05);BF-25%组、BF-30%组和BF-35%组的血清碱性磷酸酶和溶菌酶活性显著高于对照组和BF-20%组(P0.05),而其血清中总蛋白含量、白蛋白含量、谷丙转氨酶和谷草转氨酶活力差异不显著(P0.05)。研究表明,零换水条件下饲料中35%蛋白水平减少至25%并不影响团头鲂幼鱼的生长和非特异性免疫力。 相似文献
5.
通过向养殖水体中泼洒糖蜜构建生物絮团养殖模式,分析生物絮团营养组成,并探讨生物絮团对罗氏沼虾体组成和消化酶活性的影响。试验分对照组和试验组(生物絮团组),其中试验组在养殖过程中泼洒糖蜜。试验在室内水泥池内(2 m×2 m×0.6 m)进行,每个处理有3个重复,每个重复225尾虾(0.26 g±0.02 g),试验周期为90 d。养殖过程中不换水,糖蜜的泼洒量根据饲料投喂量进行计算(C/N为20)。结果显示:添加糖蜜能够显著促进生物絮团的形成,到第90天时,试验组的絮团体积达21.22 mL/L;而对照组为6.03 mL/L;试验组絮团粗蛋白含量为29.47%,粗脂肪含量为4.32%,二者均显著高于对照组,而粗灰分含量为11.36%,显著低于对照组;泼洒糖蜜对罗氏沼虾体组成的影响不显著,对照组和试验组肌肉粗蛋白含量分别为21.09%和21.20%,粗脂肪含量分别为2.91%和3.06%;另外,向水体中泼洒糖蜜对罗氏沼虾消化酶活性影响显著。试验组罗氏沼虾肠脂肪酶活性、胃脂肪酶活性和胰脂肪酶活性均显著高于对照组;试验组罗氏沼虾糜蛋白酶活性、胰蛋白酶活性也均显著高于对照组。但泼洒糖蜜对肠淀粉酶、胃蛋白酶、胃淀粉酶、胰淀粉酶和纤维素酶活性没有显著影响。试验表明,生物絮团营养组成丰富,能够有效提高消化酶活性。 相似文献
6.
碳氮比(C/N)调控是生物絮团养殖的核心技术特征,相关研究和实践中C/N中的碳和氮有不同的表征形式,本研究用溶解有机碳(dissolved organic carbon, DOC)表征碳,分别用总氮(total nitrogen, TN)、溶解无机氮(dissolved inorganic nitrogen, DIN)、总氨氮(total ammonia nitrogen, TAN)表征氮,比较了相同C/N、不同氮素形式条件下生物絮团的氨氮去除能力、基本营养组分、氮代谢相关功能基因及总异养菌数量。实验设置A组DOC/TN为20, B组DOC/DIN为20, C组DOC/TAN为20。各实验组8 h内可将10 mg/L氨氮降低到1 mg/L以下, TAN去除速率分别为(2.11±0.05)mgTAN/gTSS·h、(2.00±0.02)mgTAN/gTSS·h和(2.09±0.02)mgTAN/gTSS·h,A组显著高于B组(P<0.05),C组与A、B组无显著差异。各组絮团粗蛋白含量无显著差异,C组絮团粗脂肪含量显著高于B组和A组(P<0.05),主要氨基酸和脂肪酸组分含量... 相似文献
7.
为了解硝化型和光合自养型生物絮团对于泥鳅(Misgurnus anguillicaudatus)的养殖效果, 设置清水组(CW 组)、硝化组(BFT 组)和光合自养组(ABFT 组)生物絮团养殖泥鳅 45 d, 比较泥鳅的生长和消化酶活性、两类絮团的营养组成情况, 以及养殖水体和泥鳅肠道微生物的群落结构。结果显示, BFT 组和 ABFT 组的饲料转化率、特定生长率和末均重没有显著性差异(P＞0.05)。与 CW 组相比, 两实验组的饲料转化率显著降低; BFT 组的终末密度与 CW 组相比没有显著性差异(P＞0.05)。与 CW 组相比, BFT 组和 ABFT 组生物絮团可以提供(36.69±1.17)%和 (40.20±1.05)%的粗蛋白; 与 BFT 组相比, ABFT 组的生物絮团粗脂肪含量显著提高(P＜0.05), 并且促进脂肪酸由饱和向不饱和转化。ABFT 的泥鳅胰蛋白酶和脂肪酶的活性显著高于另外两组(P＜0.05)。微生物群落分析表明, 添加藻类对成熟生物絮团 Alpha 多样性指数、群落门水平和属水平没有显著影响。泥鳅摄食生物絮团会导致肠道菌群 sobs 指数显著降低。BFT 组肠道的优势菌群为变形菌门(Proteobacteria)、放线菌门(Actinobacteriota)和绿弯菌门 (Chloroflexi); ABFT 组为变形菌门和蓝藻门(Cyanobacteria)。属水平上, ABFT 组检测到高水平的气单胞菌属 (Aeromonas)。本研究表明, 硝化型和光合自养型生物絮团养殖均适合作为泥鳅绿色健康养殖的新模式。 相似文献
8.
生物絮团对锦鲤生长及养殖水体水质的影响 总被引：1，自引：0，他引：1
为了研究生物絮团对观赏鱼类生长影响及对养殖水质净化效果,通过设置对照组和生物絮团组(碳氮比为20:1)进行了锦鲤养殖效果对比试验。30d的试验结果显示,生物絮团组锦鲤的特定生长率相比对照组显著提高(P0.05),饲料系数相比对照组显著降低(P0.05),成活率两者之间无显著差异(P0.05)。在池塘水质净化方面,生物絮团组的亚硝酸盐氮浓度和氨氮含量变化趋势一致,呈现先升高后逐渐下降的趋势,生物絮团系统达到稳定后,生物絮团组的二态氮含量显著低于对照组(P0.05)。研究表明,生物絮团技术应用在锦鲤养殖中能有效净化池塘水质,同时可促进锦鲤生长。生物絮团通过实现饲料中蛋白质的二次有效利用,提高了饲料利用效率,降低了养殖成本、减少了水体污染。 相似文献
9.
为了探讨人工悬浮生物絮团在凡纳滨对虾养殖中的应用效果,优化生物絮团技术的使用方法,分别以甘蔗渣和稻壳粉为载体,配合芽孢杆菌BZ5制成甘蔗渣人工悬浮生物絮团和稻壳粉人工悬浮生物絮团,然后将其应用于凡纳滨对虾养殖系统,通过定期检测养殖环境中的水质指标、絮团含量、细菌数量以及对虾生长指标,评估添加人工悬浮生物絮团对凡纳滨对虾生长和养殖环境的影响。试验结果,甘蔗渣组和稻壳粉组养殖水体中的总氨氮(TAN)和总溶解态氮(TDN)水平低于对照组(P 0. 05);试验组单位水体的弧菌数量均维持在0～1×10~3CFU/m L;稻壳粉组对虾的成活率(50. 8%)显著高于对照组和甘蔗渣组(P0. 05),比对照组高27. 0%;稻壳粉组和甘蔗渣组的饲料系数(分别为1. 62和1. 87)显著低于对照组(P0. 05),分别比对照组低16. 5%和27. 7%;稻壳粉组和甘蔗渣组的单位面积对虾产量分别为2. 53 kg/m~2和2. 2 kg/m~2,分别比对照组(1. 82 kg/m~2)高39. 0%和20. 9%,且稻壳粉组显著高于对照组(P 0. 05);甘蔗渣组对虾的体长、体质量显著高于稻壳粉组(P 0. 05),与对照组无显著差异。结果表明,在凡纳滨对虾养殖系统中添加甘蔗渣人工悬浮生物絮团和稻壳粉人工悬浮生物絮团,能够为细菌提供缓释碳源和附着表面,促进益生菌的生长和繁殖,维持良好的水质,还能在一定程度上促进对虾生长,提高对虾的成活率,降低饲料系数。 相似文献
10.
本研究旨在研究饲料中添加果寡糖和德式乳酸菌(Lactobacillus delbrueckii)对锦鲤(Cyprinus carpio)生长、血液指标和抗氧化指标的影响。选取锦鲤 360 尾随机分为 4 个处理组, 每组 3 个重复, 第 1 组投喂基础日粮(D1), 第 2 组投喂基础日粮+0.3%果寡糖(D2), 第 3 组投喂基础日粮+1×107 德式乳酸菌(D3), 第 4 组投喂基础日粮+0.3%果寡糖和 1×107 德式乳酸菌(D4)。结果表明: 投喂 D4 组饲料的锦鲤增重率、特定生长率和蛋白质效率最高, 显著高于对照组(P＜0.05), 且该组的饵料系数最低; 肠道蛋白酶活性在 D4 组最高, 显著高于对照组和 D2 组(P＜0.05), 各实验组的脂肪酶活性都显著高于对照组(P＜0.05), D2 组的淀粉酶显著高于对照组(P＜0.05), 但各实验组并无显著差异 (P＞0.05)。各实验组谷草转氨酶(AST)、谷丙转氨酶(ALT)酶活性以及甘油三酯(TG)、总胆固醇(TC)含量与对照组相比均有降低, 其中 D4 组 AST、ALT 活性和 TC 含量显著低于对照组(P＜0.05); 各组血清总蛋白和白蛋白均无显著差异(P＞0.05)。血液免疫指标和肝脏抗氧化指标在实验组都有不同程度的升高, 其中溶菌酶(LYS)、酸性磷酸酶 (ACP)、超氧化物歧化酶(SOD)、总抗氧化酶(T-AOC)、过氧化氢酶(CAT)活性以及补体 C3 含量在 D3 组和 D4 组均显著高于对照组(P＜0.05), 但是和 D2 组差异并不显著(P＞0.05), 补体 C4 的含量在实验组含量都显著高于对照组 (P＜0.05); AKP 和 GPX 活性各组之间差异均不显著(P＞0.05); MDA 含量在 D3 组和 D4 组显著低于对照组(P＜0.05), 各实验组之间差异不显著(P＞0.05)。结论认为, 锦鲤饲料中添加 0.3%果寡糖和 1×107 德式乳酸菌可提高锦鲤的生长性能、肠道消化酶活性, 改善其免疫和抗氧化功能, 且果寡糖和德式乳酸菌配伍使用效果更佳。 相似文献
11.
Effects of different carbon sources addition on nutrition composition and extracellular enzymes activity of bioflocs,and digestive enzymes activity and growth performance of Litopenaeus vannamei in zero‐exchange culture tanks 
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下载免费PDF全文 Chao Wang Luqing Pan Kaiquan Zhang Wujie Xu Dahu Zhao Lin Mei 《Aquaculture Research》2016,47(10):3307-3318
A 35‐day feeding experiment was conducted to investigate the effects of different carbon sources addition on nutritional composition and extracellular enzymes activity of bioflocs, and digestive enzymes activity and growth performance of Litopenaeus vannamei juveniles (average 5.52 ± 0.21 g) in zero‐water exchange culture tanks. Molasses, corn flour and wheat bran were used as carbon sources and added into the tanks to promote the development of bioflocs during the experiment. During the entire experiment, good water quality and biofloc development were achieved under the addition of different carbon sources. At the end of the experiment, the proximate composition and extracellular enzymes activities of the collected bioflocs from seven biofloc groups were influenced by the addition of the different carbon sources. Meanwhile, the specific activities of protease, amylase, lipase and cellulase in the hepatopancreas, stomach and intestine of the shrimp showed differences among the seven biofloc groups, and most of them were significantly higher than those obtained in the control group (P < 0.05). There were differences in the performance (growth and FCR) of the shrimp among the seven biofloc groups, and all of them were significantly better than those obtained in the control group (P < 0.05). Based on the results of this study, 60% molasses + 20% corn flour + 20% wheat bran could be an appropriate formula of the addition of carbon sources for intensive culture of L. vannamei (mainly in terms of growth and FCR) in zero‐water exchange culture tanks. 相似文献
12.
A 30‐day experiment was conducted to evaluate inorganic nitrogen control, biofloc composition and shrimp performance in zero‐exchange culture tanks for juvenile L. vannamei offered a 35% (P35) or 25% (P25) crude protein feed, each feed supplemented with additional carbohydrate to increase the C/N ratio to 20:1 (CN20) or 15:1 (CN15). Sucrose was used as a carbohydrate to manipulate the two C/N ratios based on the carbon and nitrogen content of both the feeds and sucrose. The four treatments were referred to as: P35 + CN20, P35 + CN15, P25 + CN20 and P25 + CN15. Each treatment consisted of four replicate tanks (125 L), each stocked with 28 shrimp (equivalent to 224 shrimp m?3). Bioflocs formed and developed based on initial inoculation in all four treatments; and monitored water quality parameters were maintained within acceptable ranges for shrimp culture throughout the experiment. No significant effects (P > 0.05) of dietary protein level, C/N ratio or their interaction were observed on biofloc development (BFV, TSS and BFVI) and inorganic nitrogen (TAN, NO2?‐N and NO3?‐N) concentrations. At the end of the experiment, proximate analysis of the bioflocs collected from the four treatments showed crude protein levels of 21.3% ~ 32.1%, crude lipid levels of 1.6% ~ 2.8% and ash levels of 43.4% ~ 61.4%. Extracellular protease and amylase activities of the bioflocs were 9.9 ~ 14.4 U g?1 TSS and 293.5 ~ 403.8 U g?1 TSS respectively. Biofloc composition and enzyme activity were both affected by dietary protein level (P < 0.01) and C/N ratio (P < 0.05). Survival, per cent weight gain and protein efficiency ratio of shrimp were not affected (P > 0.05) by dietary protein level, C/N ratio or their interaction; however, the feed conversion ratios were significantly lower (P < 0.05) in treatments with high dietary protein (P35) compared with those in treatments with low dietary protein (P25). The results from this study demonstrate that dietary protein level and C/N ratio manipulation can have important implications for water quality, biofloc composition and shrimp performance in intensive, zero‐exchange biofloc‐based culture systems. 相似文献
13.
Julie Ekasari Rovi Setiawati Fitria Rahmadani Ritonga Mia Setiawati Muhammad Agus Suprayudi 《Aquaculture Research》2019,50(7):1802-1811
The objective of the study was to evaluate the utilization of biofloc meal as a feed ingredient in enhancing the growth and health status of African catfish (Clarias gariepinus) juvenile. The study consisted of two experiments, that is digestibility and growth experiments. The digestibility of two biofloc meals produced with two different carbon sources, that is tapioca and molasses, were assessed in the digestibility experiment. Whereas the effect of four dietary treatments with different levels of biofloc meal, that is 0%, 5%, 10% and 20%, on the fish growth performance, feed utilization, immuno‐haematological response, antioxidant status and robustness against environmental stress were evaluated in the growth experiment. The results showed that the digestibility of dry matter, protein, lipid and phosphorus of biofloc grown using molasses as the carbon source were remarkably higher than that grown using tapioca (p < 0.05). The inclusion of biofloc meal in the diets at 10% and 20% resulted in higher feed intake, fish growth and final biomass and protein efficiency ratio, and lower feed conversion ratio (p < 0.05). Furthermore, the red blood cells counts, phagocytic, lysozyme activities and antioxidative capacity were significantly enhanced in the fish provided with diet containing 20% biofloc meal (p < 0.05).The fish survival following salinity stress test was higher in the treatments with biofloc meal at 10% and 20% inclusion levels. In conclusion, dietary inclusion of biofloc meal could improve the growth performance and health status of African catfish juvenile and an inclusion level of 20% could be recommended. 相似文献
14.
A 30‐day experiment was performed to investigate the effects of bioflocs on water quality, and survival, growth and digestive enzyme activities of the white shrimp Litopenaeus vannamei. Altogether 28 shrimp (7.4 ± 0.1 g) were stocked in each 150 L tank. Two bioflocs treatments and one control were managed: ‘bioflocs 1’ and ‘bioflocs 2’ based on two different densities of the bioflocs, and clean water control without the bioflocs. Brown sugar was added to the bioflocs 1 and bioflocs 2 treatment tanks accounting for 28% and 80% of the shrimp feed respectively (corresponding to proximate C/N ratios of 10 and 14 in daily additions of organic matter respectively), so as to promote bioflocs production and approximately 14 mL L?1 in treatment bioflocs 1 and 20 mL L?1 in treatment bioflocs 2 were maintained from day 15. Monitoring of selected water quality parameters throughout the whole experiment period showed that all parameters remained within recommended levels for shrimp culture in the bioflocs treatments at zero‐water exchange, especially low total ammonia nitrogen and nitrite nitrogen levels. By the end of the experiment, shrimp survival rates were above 86%, with no significant differences (P > 0.05) among the three groups. Both weight gain rate and special growth rate tended to increase in the bioflocs treatments compared to those in the control. Meanwhile, the overall specific activities of protease, amylase, cellulase and lipase of the shrimp in the bioflocs treatments were all higher than those in the control; and for the specific activity of the same digestive enzyme, the differences between the bioflocs treatments and the control performed inconsistently among different organs: hepatopancreas, stomach and intestine. Present results suggest that the bioflocs can not only maintain favourable water quality conditions for shrimp culture and help shrimp grow well in zero‐water exchange culture systems, but may also have a positive effect on digestive enzyme activities of the shrimp. 相似文献
15.
We evaluated the technical feasibility of reducing water dependency of rohu, Labeo rohita, culture with biofloc under light-limited indoor culture. Biofloc and control treatments were conducted in 700-L indoor tanks at three different stocking densities (STD): 1.3, 2.6, and 3.9 Nos. fish m?2 of surface area of tank for a period of 90 days. In biofloc treatment, fish were fed 20% crude protein feed and extra organic carbon in the form of wheat flour, whereas in case of control treatment they were fed 30% crude protein feed only. Fish survival was 100% in both the treatments. Lower stocking density produced larger fish, but growth was similar within stocking densities among control and biofloc treatments. The nutritional quality of biofloc was found to be quite suitable for rohu. Frequency of water exchange was significantly less in biofloc treatments as compared to the control ones. 相似文献
16.
生物絮团养殖模式下益生菌添加对异育银鲫生长、消化酶活性及肠道组织结构的影响 总被引：2，自引：0，他引：2
前期研究表明,生物絮团技术(biofloc technology,BFT)适于异育银鲫(Carassius auratus gibelio)养殖。为进一步优化BFT养殖模式,本研究设置3个实验组:BFT模式下EM菌添加组(BB组)、枯草芽孢杆菌(Bacillus subtilis)添加组(BI组)和BFT对照组(B组),以均体重(1.60±0.50)g的异育银鲫为研究对象,探讨BFT模式下外源添加益生菌对养殖动物生长、消化酶活性及肠道组织结构的影响。结果表明:(1)益生菌添加组异育银鲫增重率和特定生长率显著高于对照组(P0.05),BB和BI组的增重率分别提高了216.70%和184.04%,特定生长率分别提高了141.18%和125.49%,BB和BI组间差异不显著(P0.05);(2)益生菌添加组(BB组和BI组)的消化酶(淀粉酶、脂肪酶和胃蛋白酶)活性均显著高于对照组(B组)(P0.05)。益生菌添加组间,BB组淀粉酶活性显著高于BI组(P0.05),脂肪酶和胃蛋白酶活性亦高于BI组,但差异不显著(P0.05);(3)益生菌添加组肠道肌层厚度和黏膜下层厚度显著高于对照组(B组)(P0.05),BB组异育银鲫肠道黏膜皱襞高度和皱襞间质宽度与BI和对照组相比,均无显著差异(P0.05)。研究表明,BFT养殖模式下外源添加益生菌可以更好地促进异育银鲫生长。 相似文献
17.
Effects of Different Carbon Sources on Bioactive Compound Production of Biofloc,Immune Response,Antioxidant Level,and Growth Performance of Litopenaeus vannamei in Zero‐water Exchange Culture Tanks 下载免费PDF全文
下载免费PDF全文 Dahu Zhao Luqing Pan Fei Huang Chao Wang Wujie Xu 《Journal of the World Aquaculture Society》2016,47(4):566-576
This study aimed to investigate the development and bioactive compounds of biofloc promoted by adding molasses and wheat bran to zero‐water exchange culture tanks and their effects on physiological parameters and growth performance of juvenile Litopenaeus vannamei (initial weight: 6.8 ± 0.4 g). Different combinations of molasses and wheat bran were added as carbon sources: T1, 100% molasses; T2, 50% molasses + 50% wheat bran; T3, 25% molasses + 75% wheat bran. Clear water tanks with water exchange served as the control group (control). After the 30‐d experiment, the development of biofloc in terms of total suspended solids (TSS) and biofloc volume (BFV) showed significant differences in the three biofloc treatments, especially the highest levels of TSS and BFV observed in T3. The levels of poly‐beta‐hydroxybutyrate or polysaccharide in the biofloc of T1 and T2 were significantly higher than those in T3. Meanwhile, compared with the control group, most of the immune and antioxidant parameters and growth performance of shrimp were significantly enhanced in biofloc treatments, especially in T1 or T2. In conclusion, different carbon sources could effectively affect the development and bioactive compounds of biofloc, which could improve physiological health status and growth performance of shrimp in zero‐water exchange systems. 相似文献
18.
Mohammad Hossein Khanjani Morteza Alizadeh Moslem Sharifinia 《Aquaculture Nutrition》2020,26(2):328-337
The present study assessed the effects of different types of feeds and salinity levels on water quality, growth performance, survival rate and body composition of the Pacific white shrimp, Litopenaeus vannamei, juveniles in a biofloc system. Shrimp juveniles (2.56 ± 0.33 g) were cultured for 35 days in 300 L fibreglass tanks (water volume of 180 L) with a density of 1 g/L in six treatments. Three sources of feed (100% formulated feed, mixture of 66.6% formulated diet and 33.3% wet biofloc, and 100% wet biofloc) and two levels of salinity (10 and 32 ppt) were considered in two control groups and four biofloc treatments. Water quality parameters in the biofloc treatments were significantly better than control groups (p < .05). The highest increase in growth performance and survival rate were obtained in salinity of 32 ppt and mixed feed sources. Analysing the proximate composition of body shrimp indicates an increase in lipid and ash levels in biofloc treatments, which was more evident in the salinity of 32 ppt. In addition, the proximate analysis of shrimp body showed significant differences between biofloc treatments and control groups (p < .05). The highest FCR was found in the treatment with salinity level of 10 ppt and fed only with floc. Overall, it was found that the artificial diet supplemented with biofloc at the salinity of 32 showed better performance in the juvenile stage of Pacific white shrimp. 相似文献
19.
Mohammad T. Ridha Md Arshad Hossain Ismail S. Azad Maria Saburova 《Aquaculture Research》2020,51(10):4225-4237
This study compared the effect of three sources of carbohydrates: sugar, wheat and malt flours, on water quality, water consumption, bacterial load, growth and flesh quality of Nile tilapia. Adults (120.6 ± 0.64 g) were stocked in 1.2‐m3 fibreglass tanks at a rate of 25 fish/m3. Carbohydrates were added to the biofloc tanks at a C:N ratio of 20:1. Water flow in the non‐biofloc control tanks was adjusted to 0.6 L/day. The 105‐day experiment was conducted in triplicates. Results showed that biofloc treatments (BFT) with zero water exchange had significantly higher mean total ammonia, nitrites, nitrates, alkalinity, total suspended solids and lower pH than the control treatment. The sugar BFT had the highest floc volume. Growth parameters and feed conversion ratio did not differ significantly among treatments. However, tilapia in the malt flour and control treatments had close values. Gross fish yield was higher (p < .05) in the control than the BFT treatments. Water consumption/kg tilapia produced in the control was 42 times higher than the BFT groups. Protozoa dominated the biofloc biota, and wheat flour was the best in harbouring higher bacterial populations in the gut. Protein content and ∑n‐3 fatty acids were highest in the wheat flour biofloc, while malt flour biofloc had the highest lipids. The sugar biofloc had the highest n‐3/n‐6 ratio. Tilapia muscles in the malt flour and control treatments had the highest protein and lipid contents respectively. Tilapia muscles in the wheat flour BFT had the highest ∑n‐3 fatty acids and n‐3/n‐6 ratio. It can be concluded that farming tilapia in BFT using malt or wheat flours as carbon sources is more economical in saving great amount of water with minimal discharge of pollutants without affecting tilapia growth or flesh quality. 相似文献