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从褶皱臂尾轮虫(Brachionus plicatilis)的基础环境因子和控制因子等各方面阐述如何提高轮虫增殖率。褶皱臂尾轮虫的适宜繁殖条件:最适pH值7~8,最适温度35℃,最适盐度18‰,比重1.016,光照4 400~10 000lx,溶氧1.5mg/L以上。轮虫接种密度以1个/mL为宜,池中轮虫繁殖密度以100个/mL为宜。提倡用光合细菌+扁藻投喂轮虫,慎用酵母培养褶皱臂尾轮虫。在适宜条件下,经10d的培养,褶皱臂尾轮虫可由原来的1个/mL增殖到1 500~2 000个/mL。 相似文献
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光合细菌配合面包酵母与藻粉培养轮虫的实验 总被引：2，自引：0，他引：2
以面包酵母与一定量螺旋藻粉培养褶皱臂尾轮虫的过程中，添加光合细菌液进行实验。结果表明：光合细菌作为辅助性饵料，对轮虫的生长具有明显特殊的促进作用。4组实验显示：投喂适宜量光合细菌轮虫增殖明显加快，但与光合细菌添加量的增加不完全呈正比关系；投喂光合细菌新鲜培养液与老培养液轮虫增殖效果相近；投喂光合细菌只能作为辅助性饵料。当配合酵母、藻粉培育轮虫时，3者在饵料上起到了良好的互补作用，培养效果最佳。 相似文献
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用干酵母作为褶皱臂尾轮虫的饵料,进行工厂化培养试验。结果表明:(1)在水温25~28℃,盐度23-25。连续充气的条件下,轮虫生长繁殖稳定;(2)经过7-10 d的培养,A、B、C三个水泥池内轮虫的密度分别从接种时的16、23、38个／ml增加到269、312、266个／ml.平均日增殖率为0.346、0.404、0.443;(3)A、B、C三个水泥池,连续培养59~70 d,经52-63次采收,分别收获褶皱臂尾轮虫1494×108、1748×108、2149.2×108个,合计收获轮虫5391.2×108个,饵料生产力为7.17、8.54、10.55;(4)采用合适的干酵母投喂方法和投喂量,定期带水采收,使轮虫密度保持在200~300个／ml,并补充等量培养用水,可以获得长期稳产的效果。 相似文献
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对虾幼体进入溞状幼体三期以后,饵料成了育苗的关键,因此,培养一种小型的动物性饵料,就显得很重要。几年来,我们在工作实践中,用褶皱臂尾轮虫培养对虾幼体取得了很好的效果,现将培养褶皱臂尾轮虫(以下简称轮虫)的方法介绍如下:首先要培养好褶皱臂尾轮虫的饵料。单胞藻的扁藻、盐藻、小球藻等绿藻是轮虫的主要饵料,以扁藻为最好。当水温上升到15℃左右时,我们在有上列几种藻种的土池里进行肥水繁殖,施氮肥10ppm(未施磷肥)、在4日30日到5月18日间共施肥4次,同时也施少量人粪。 相似文献
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在人工海水条件下，利用面包酵母培养褶皱臂尾轮虫（Brachionus plicatilis）的研究 总被引：1，自引：0，他引：1
在充气、以面包酵母为饵料、盐度为20的条件下,进行人工海水培养褶皱臂尾轮虫的实验。结果表明,不同人工海水中,用速溶海水晶配制成的海水和自然海水稀释的海水培养褶皱臂轮虫的效果明显地优于粗盐配制的;用速溶海水晶配制成的海水培养褶皱臂尾轮虫时,最大密度能达1710个／ml。不同营养强化剂中,绿色巴夫藻、扁藻以及胶囊肝油 蛋黄的效果较好。添加剂4ppm氯霉素时,培养褶皱臂尾轮虫的效果较好。 相似文献
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利用越冬后闲置的温室大棚,在水泥池内用天然海水和含有藻种的养殖废水培育褶皱臂尾轮虫。培育用水的比重为1.009~1.011,水温16~25℃,轮虫种由培育池内上一年的冬卵萌发而成,以小球藻、微绿球藻等混合型藻类作为轮虫的饵料。试验结果表明,温度是培育轮虫的一个关键因素,水温在18~25℃时,培育15d即可达到密度峰值。如全部采用养殖废水,培育不出轮虫;若培育过程中不用敌百虫杀灭敌害,则轮虫产量低。饵料是培育轮虫的另一个关键因素,以藻类作饵料,操作简便,易管理,轮虫在投喂前也无须事先强化培育。此种培育方法具有操作简便,产量高而稳定,可以提前培育等优点。 相似文献
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IntroductionInherent to the practice of intensive aquaculture is the generation of wastes having immediate and verybroad effects on the aquatic environment.There is a growing consensus about the need to reduce waste pro-duction in aquaculture to minimize the negative impacts on the environment.Nitrogen(N) and phosphorus(P) wastes are major concerns for many aquaculture operations.In the past,formulation of diets in intensive aquaculture was often aimed at meeting requirements formaximum growt… 相似文献
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V. C. Rubio F. J. Snchez-Vzquez J. A. Madrid 《Aquaculture (Amsterdam, Netherlands)》2003,220(1-4):697-705
European sea bass exhibits a feeding rhythm with seasonal phase inversions: nocturnal feeding is predominant in winter, and diurnal feeding during the rest of the year. This explains the increased growth of sea bass fed at night during the winter months, but to fully assess such feeding practices, it is important to monitor food-catching efficiency in the dark. To evaluate the influence of nocturnal feeding on pellet-capture efficiency under laboratory conditions, we developed an infrared pellet detector linked to on-line recording with a microcomputer. Feed waste was recorded for eight groups of four sea bass (54.6±15.8 g body weight) fed either diurnal or nocturnal meals with long (>60 s) or short (<20 s) feed availability times. With short feed availability times, food-catching efficiency in complete darkness (0 lx) was reduced to 78.6%, compared to 93.5% in diurnally fed fish. This was confirmed in a second experiment, performed during winter, involving 4000 sea bass in four sea cages (1000 per cage) provided with self-feeders and pellets detectors. Feed waste amounted to less than 13% of the food distributed, but nocturnal demands (29% of total feed demands) were accompanied by higher levels of uneaten pellets (68% of the total feed waste) than diurnal demand. This suggests that if the aim is to reduce feed waste, nocturnal feeding should be restricted in sea cages. 相似文献
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对虾配饵中动、植物蛋白比接近1:1为宜,如果动物蛋白不足,对虾生长发育不良,易感染各种疾病。配饵中添加鱼油试验经生物统计表明,鱼油是对虾增重的第一限制因子。配饵中缺乏鱼油,对虾食欲不振,会引起消化生理代谢障碍。对虾配饵原料质量如油脂氧化酸败与原料霉变及霉变产生的毒素,对对虾生长极其不利。不仅使虾体瘦弱,抗病力减弱,而且死亡率比对照组明显增高。因此,对虾配饵精选原料是保证配饵质量、减少发病率、提高成活率的关键因素。 相似文献
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The effects of protein restriction in the diet with subsequent realimentation on growth responses of juvenile Chinese shrimp, Fenneropenaeus chinensis (initial mean wet weight 1.347 g), were investigated. The control group (Group C) was fed an adequate diet containing 44.6% crude protein and 18.5 kJ gross energy/g dry matter throughout the experiment. For treatment Groups T15 and T30, in the restriction phase (weeks 1–2) dietary crude protein contents were reduced to 15.0% and 29.3%, respectively, with constant energy supply, while in the realimentation phase (weeks 3–6) they were supplied with the same diet as the control group. Protein restriction led to significant decrease in specific growth rates and body weight of shrimp. However, when the shrimp were transferred from protein restriction to realimentation, they had significantly increased specific growth rates in terms of dry matter, protein and energy (SGRd, SGRp and SGRe) compared with the control shrimp. At the end of the experiment, the shrimp in Group T30 achieved complete growth compensation, while those in Group T15 were still significantly smaller than the controls. As dietary protein levels reduced, feed conversion efficiencies and apparent protein digestibility decreased, but feed intake and protein efficiency ratio increased. The shrimp responded to a change from protein restriction to realimentation by displaying improved feed conversion efficiencies (FCEd, FCEp and FCEe) compared with the controls, although those in Group T15 delayed in showing the enhanced FCE values. In the initial 2-week realimentation, the shrimp in Group T15 showed significantly higher feed intake, and lower apparent digestibility of dry matter and protein than those of the controls. There was no significant difference in protein efficiency ratio among all groups in the realimentation phase. The above results suggest that compensatory growth in Group T30 is mainly dependent on improved feed conversion efficiencies, while that in Group T15 is attributable to both improved feed conversion efficiencies and increasing feed intake. After 2-week restriction, the shrimp showed lower body crude protein, lipid and energy content, and higher moisture and ash content than the controls. However, during the course of realimentation, the differences between the previously protein restricted shrimp and the controls diminished. This indicates that compensatory growth after a period of protein restriction in juvenile Chinese shrimp was accompanied by a complete recovery in body composition and energy content. 相似文献
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应用SPC技术监控饲料生产质量 总被引：1，自引：0，他引：1
本文介绍了应用SPC技术（统计过程控制）监控饲料生产质量的方法。文章在分析SPC技术改进质量的过程之后，介绍了SPC监控原理和休哈特控制图，然后通过一个例子说明如何绘制控制图并进行饲料粗蛋白含量变异的监控。 相似文献
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稚、幼鳖饲料配方的研究 总被引：1，自引：0，他引：1
设计了９种稚、幼鳖饲料,共进行４次饲养试验。软颗粒饲料（自然干燥,含水率约１０％）可以取得极高的饲料利用率,获得１０００ｇ鳖肉仅需耗费饲料蛋白５７０ｇ,远优于市售商品饲料１２００ｇ的值。唯稚鳖对其嗜好性差,摄食量少,致生长速度缓慢。以国产鱼粉和秘鲁鱼粉（均为褐色鱼粉）作为主要蛋白源加工成的软颗粒饲料和粉状饲料（制成面团）均未取得好的饲养效果。饲料中含有３８．７％的植物蛋白（豆粕、生物蛋白粉）,同时减少鱼粉用量,稚鳖的生长和饲料效率这两个主要指标均有下降,但成本可大幅度降低,表明植物蛋白在饲料中应占有适当份额,比例过高并不适宜。生物蛋白粉的适口性优于豆粕。通过调整粘结剂的种类与数量等方法,可以较大幅度地改变现行鳖饲料的配方模式,达到提高水稳定性、降低成本并获取良好饲养效果的目的。本文报导的Ｄ和Ｂ１饲料即属这一类型,其试养实绩明显优于某品牌市售商品饲料。 相似文献
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L.E. CRUZ-SUÁREZ M. TAPIA-SALAZAR M.G. NIETO-LÓPEZ C. GUAJARDO-BARBOSA & D. RICQUE-MARIE 《Aquaculture Nutrition》2009,15(4):421-430
Three experimental diets were formulated to contain 33 g kg−1 seaweed meals, made of wild brown algae (kelps) Macrocystis pyrifera (MAC) and Ascophyllum nodosum (ASC) or of a cultivated green alga Ulva clathrata (ULVA). The diets were fed to juvenile white shrimp Litopenaeus vannamei (1.6 g) for 28 days. Loss of dry matter (LDM) and loss of protein (LP) after 1 hour immersion in seawater, and distilled water absorption (WA) were analyzed in the pelleted diets, as well as shrimp weight gain, feed intake, feed conversion ratio (FCR), survival, protein efficiency ratio (PER) and body pigmentation. Feed intake, FCR and PER were corrected for nutrients preprandial losses in seawater. ULVA diet resulted in lower LDM, but a higher LP and also higher WA, indicating a modification of the pellet physical quality (better hydro stability). No significant differences in feed consumption and survival were found, but ULVA diet resulted in a slightly higher final weight (4.8 for ULVA versus 4.6 and 4.3 g for ASC and MAC), and better FCR (1.7 versus 1.9 and 2.1) and PER (2.0 versus 1.7 and 1.5), the differences with MAC diet being significant (Duncan, α = 0.05). Red color after cooking was markedly darker in the ULVA fed shrimp. 相似文献
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试验以Cr2O3为指示物,以70%基础饲料和30%的待测饲料原料组成试验饲料,在室内流水养殖系统中,采用虹吸法收集粪便,测定了初始体重为30±2.3 g的鲈鱼Lateolabrax japonicus对白鱼粉、血粉、虾糠、羽毛粉、双低菜粕、高筋粉和米糠中干物质、粗蛋白和能量的表观消化率.试验结果表明,鲈鱼对不同饲料原料的干物质表观消化率为98.71%～41.84%.其中白鱼粉为98.71%,显著高于其他各组(P<0.05).鲈鱼对白鱼粉和米糠的蛋白表观消化率很高,均在98%以上,双低菜粕也较高,为86.86%,血粉、羽毛粉和高筋粉在62.94%～71.08 9,6之间,虾糠仅为45.01%,显著低于其他各组(P<0.05).鲈鱼对不同饲料原料的能量表现消化率为95.24%～65.54%,对白鱼粉和高筋粉在90%以上,对血粉、羽毛粉、双低菜粕和米糠的能量表观消化率在74%以上.进行70 d的饲养实验后,取鲈鱼肝脏和肠道组织制作切片.观察到血粉、羽毛粉、双低菜粕、高筋粉和米糠对鲈鱼肝脏表现出肝损害所致的组织炎症反应、肝细胞水样变性和脂肪变性等病理特征.血粉、羽毛粉、双低菜粕组鲈鱼肠道皱襞出现顶端上皮细胞脱落、炎症细胞浸润等病理症状. 相似文献