维生素E对克氏原螯虾生殖的影响

实验用不同的维生素E(VE)含量的饲料投喂克氏原螯虾亲虾,研究对其繁殖性能的影响,目的是为研制亲虾的人工饲料提供指导.结果显示,在添加VE量分别为基础饲料干重的0%、0.004%、0.02%、0.1%和0.5%的5个饲料组中,0.02%VE组不仅可以增加产卵雌虾的数量比例,而且也能提高克氏原螯虾雌虾的产卵量.随着VE含量的升高,产卵雌虾的比例呈下降趋势,单个雌虾的产卵量与0.02%VE组差不多,这表明饲料中适当添加VE可促进克氏原螯虾产卵,但饲料中VE含量过高对克氏原螯虾的繁殖产生负面影响.在饲料中添加适量的VE能够提高亲虾繁殖能力,方法简单,效果明显,适合规模化生产的需要,可以推广.     

水草和螺蛳对克氏原螯虾性腺发育的影响

本文对水草、螺蛳、水草+螺蛳三种投喂方式对克氏原螯虾性腺发育的影响进行了研究。结果显示,水草+螺蛳组的克氏原螯虾(雌虾体长9.5cm)的抱卵量826粒/尾,显著高于水草组、螺蛳组(P<0.05),成熟度5.95%、抱卵指数19.20粒/g、亲虾成活率89.66%、抱卵率79.31%,结果均高于投喂水草组或螺蛳组。显然,植物性和动物性饵料混合喂养更有利于促进克氏原螯虾雌虾性腺发育及提高亲虾的成活率。     

克氏原螯虾人工诱导工厂化繁育关键技术研究

为了优化克氏原螯虾人工诱导工厂化繁育的关键技术,利用玻璃缸和塑料温棚水泥池开展了克氏原螯虾人工诱导繁殖、抱卵虾孵化及幼苗对冬季低温条件耐受能力的研究。采用提前放养亲虾、强化培育、搭建三角形四隔层垒起隐蔽物、孵化网袋、培育丰年虫开口饵料及适时出苗等技术措施,进行了195 d的试验。试验结果,克氏原螯虾亲虾的培育成活率达73.59 %,抱卵率达76.11 %,平均每平方米育成体长1~2 cm的幼苗2 300尾,孵化后亲虾的成活率达93.7 %;克氏原螯虾雌雄亲本选自不同水域,对亲虾培育成活率的影响不显著(P＞0.05),但长江水系和淮河水系杂交组亲虾的抱卵率显著高于自交组(P＜0.05);体长1~2 cm和2~3 cm的克氏原螯虾幼苗拥有较强的耐低温能力,可以在室外水泥池、池塘等生境中安全越冬。     

克氏原螯虾人工诱导繁殖研究初报

分别以福尔马林、高锰酸钾、食盐、聚维酮碘和溴氯海因等5种常用的水产药物对克氏原螯虾亲虾进行消毒试验,测定亲虾的成活率.试验结果表明.用这5种药物对克氏原螫虾亲虾浸泡消毒后,亲虾的成活率分别为55%、70%、35%、40%和45%.由此可以看出,采用高锰酸钾消毒可较好地提高克氏原螯虾亲虾的成活率.再采用盐水诱导、雌虾去单侧眼柄诱导和盐水刺激+雌虾去眼柄双重诱导等三种方式对克氏原螯虾亲虾进行人工诱导,促进其性腺发育,以探讨不同人工诱导方式对克氏原螯虾亲虾抱卵率的影响.试验结果显示,采用这三种诱导方式,亲虾的抱卵率分别比对照组提高了20%、31%和39%.采用双重诱导方式的平均产卵率要高于单因子诱导方式,其诱导效果明显.     

饲料中添加维生素A、C和E对克氏原螯虾生长和免疫力的影响

维生素在甲壳动物的存活、生长、繁殖过程中起重要作用。本研究采用正交设计实验,研究了维生素A、维生素C和维生素E的添加量对克氏原螯虾(Procambarus clarkii)幼虾生存、生长和免疫的影响。研究设立三个因子A、B、C,分别为维生素A、维生素C、维生素E的添加量。每个因子设3个水平,维生素A添加量的3个水平为:0.0048、0.0054、0.006%;维生素C添加量的3个水平为:0.02、0.05、0.08%;维生素E添加量的3个水平为:0.02、0.04、0.06%。极差分析结果表明,克氏原螯虾幼虾成活率最高时的因子水平组合为:A3B1/B3C2;增重率最大时的因子水平组合为:A3B2C2;丙二醛(MDA)含量、超氧化物气化酶(SOD)活性和SOD基因表达水平最低时的因子组合水平都为:A2B1C1;酚氧化酶(PO)活性最高时的因子水平组合为:A3B2C1;谷胱甘肽过氧化物酶基因GPx表达水平最低时的因子水平组合为:A3B1C1。将克氏原螯虾幼虾的成活率和增重率作为主要考虑因素,综合考虑免疫指标及成本因素,我们建议在本次实验设计的条件中,选择A3B1C2作为最佳组合方案,即维生素A添加量为0.006%、维生素C添加量为0.02%、维生素E添加量为0.04%时,最有利于克氏原螯虾幼虾的存活、生长,提高其免疫力。     

克氏原螯虾工厂化繁育技术研究

为了探索克氏原螯虾工厂化育苗技术,2008年利用室内水泥池中进行了克氏原螯虾的人工繁育试验,取得了初步的成功,亲虾培育成活率84.3%;交配抱卵率81.6%;受精卵经孵化出苗率71.9%;平均每立方水体出苗数5593尾;平均每只亲虾出苗125尾;每只抱卵虾出苗182尾.     

维生素C对克氏原螯虾生长及非特异性免疫机能的影响

为探讨维生素C对克氏原螯虾生长及非特异性免疫机能的影响,以初始体质量(3.19±0.06)g的克氏原螯虾为试验对象,分别投喂维生素C添加量为0(对照),30、60、120、240和480 mg/kg的等能等氮饲料,进行为期60 d的养殖试验.结果表明,饲料维生素C添加水平对克氏原螯虾的存活率(SR)、肝胰腺指数(HSI...     

维生素C对克氏原螯虾肝胰腺非特异性免疫的影响

为探究维生素C作为饲料添加剂短期投喂克氏原螯虾(Procambarus clarkii)对其肝胰腺非特异性免疫的影响,并寻找出最适的添加量,将规格相同(27 g±3 g)、健康无伤的克氏原螯虾暂养7 d后分5组,对照组投喂基础饲料,4个试验组投喂的饲料为在基础饲料中添加维生素C(添加量分别:0.1、0.2、0.4、0.8 g/kg)。投喂5 d后,取试验虾肝胰腺进行免疫相关酶活指标的测定,结果显示:添加0.2 g/kg的维生素C可以显著提升克氏原螯虾肝胰腺中SOD、CAT、T-AOC等抗氧化酶的活性,对于免疫酶ACP、AKP的活力依然有显著提升作用。并且对于肝胰腺中MDA的含量有降低作用(P<0.05)。0.4 g/kg添加组,能够显著提升肝胰腺中CAT活力,并且显著降低MDA含量(P<0.05)。由此可以得出在饲料中添加0.2~0.4 g/kg维生素C可以在一定程度上提升克氏原螯虾肝胰腺的非特异性免疫。     

亲虾规格、隐蔽物、光照度及密度对克氏原螯虾繁殖效果的影响

按照正交试验设计原理,不考虑交互作用,选择L9(3～4)正交表,研究了亲虾规格、隐蔽物、光照度及放养密度4个因素对克氏原螯虾亲虾成活率、抱卵率、产卵量的影响,试验历时57d。研究结果表明,不同亲虾规格对抱卵量影响显著(P0.05),且规格为35～50g亲虾的平均抱卵量为489.8粒/尾,分别较25～30g、30～35g高20.8%、11.6%;不同隐蔽物种类对亲虾的成活率影响显著(P0.05),使用"水草+石棉瓦+砖块"作为隐蔽物,亲虾平均成活率为95.69%,分别较"水草+石棉瓦+PVC管"、"三角形栖息物"高9.6%、3.5%;光照度为50～500lx,亲虾的平均抱卵量为467.17粒/尾,高于其他两个光照度水平;放养密度为20尾/m2,亲虾的平均抱卵率为64.98%,高于其他两个密度水平。因此,亲虾规格为35～50g、隐蔽物种类为‘水草+石棉瓦+砖块’、光照度为50～500lx、放养密度为20尾/m2"组合有利于提高克氏原螯虾的繁殖效果。     

维生素E对克氏原螫虾生殖的影响

实验用不同的维生素E（VE）含量的饲料投喂克氏原螯虾亲虾，研究对其繁殖性能的影响，目的是为研制亲虾的人工饲料提供指导。结果显示，在添加VE量分别为基础饲料干重的0％、0．004％、0．02％、0．1％和0．5％的5个饲料组中，0．02％VE组不仅可以增加产卵雌虾的数量比例，而且也能提高克氏原螯虾雌虾的产卵量。随着VE含量的升高，产卵雌虾的比例呈下降趋势，单个雌虾的产卵量与0．02％VE组差不多，这表明饲料中适当添加VE可促进克氏原螯虾产卵，但饲料中VE含量过高对克氏原螯虾的繁殖产生负面影响。在饲料节添加适量的VE能够提高亲虾繁殖能力，方法简单，效果明显，适合规模化生产的需要，可以推广。     

Vitamin K in fish nutrition

Vitamin K belongs to the lipid soluble vitamins, and occurs naturally as phylloquinone (vitamin K₁) and menaquinone (vitamin K₂). In addition, there is a synthetic provitamin, menadione (vitamin K₃), primarily used as a vitamin K source in animal feed. Menadione is unstable during feed processing and storage and the dietary content may reach critically low levels. Recent publications also question the availability of menadione in feed for salmonids. Vitamin K plays vital roles in blood coagulation and bone mineralization in fish, but the suggested minimum requirement varies considerably depending on the vitamin K source used. Vitamin K deficiency is characterized by mortality, anaemia, increased blood clotting time and histopathological changes in liver and gills. However, one should assess both inherent and supplemented forms of vitamin K in feeds for exact determinations, as relevant novel feed ingredients of plant origin may be sufficient to meet the requirement for vitamin K. The current review gives an overview of the biochemical role of vitamin K, and discusses vitamin K requirement in fish in light of updated literature, with special emphasis on salmonids.     

不同添加量维生素A和维生素E对海蓝褐种公鸡繁殖性能的影响

试验选用15周龄个体发育良好、冠髯大而鲜红的海蓝褐种公鸡108只,随机分为6组,每组18只,3个重复。CK为对照组,饲喂基础日粮,Ⅰ、Ⅱ、Ⅲ、Ⅳ和Ⅴ组添加水平分别为VA10000IU/kg+VE15mg/kg、VA12000IU/㎏+VE30mg/㎏、VA14000IU/Kg+VE45mg/㎏、VA14000IU/㎏+VE60mg/㎏和VA18000IU/㎏+VE75mg/Kg。结果表明,(1)试验Ⅲ组睾丸重量极显著于其他各组(P<0.01);Ⅰ～Ⅴ组睾丸纵径均极显著于CK组(P<0.01);Ⅲ组处理睾丸横径显著于CK和Ⅳ、Ⅴ组(P<0.05);(2)Ⅴ组处理射精量均极显著于其他组(P<0.01);Ⅲ组和Ⅴ组处理精子密度均极显著于其他组(P<0.01);Ⅲ组处理精子活力极显著于其他组(P<0.01);Ⅲ组和Ⅳ组受精率显著于其他各组(P<0.05);(3)各组间精子pH值无显著差异(P>0.05)。综合分析不同VA和VE水平对试验种公鸡繁殖性能指标的变化,本试验研究表明:VA和VE的适宜添加量为VA14000IU/kg+VE45mg/㎏。     

维生素E在家禽生产中的应用

对维生素E的化学结构、性质、代谢、功能等做了介绍,并阐述了维生素E在家禽生产中的应用效果。     

维生素E醋酸酯对鱼油特性的影响

油样的酸价、碘价、过氧化值随时间变化而呈现显著差异，根据碘价值推出鱼油完全酸败的时间约为75．7ld，但是实验前后主要脂肪酸的变化并不显著。与色油脂肪政变化相比碘价、酸价、过氧化值只能作为评价色油酸败指标的参考值。     

Vitamin requirements in great scallop larvae

Vitamins were analysed in food (microalgae) and larvae of great scallop, Pecten maximus, during larval development. Microalgae used to feed larvae in hatcheries show great variability in their vitamin composition depending on both the species and culture condition (phase of growth). The microalgae used to feed Pecten maximus larvae were rich in vitamins; their content compared with diets used in fish culture appeared sufficient, with the possible exceptions of pyridoxine, biotin and pantothenic acid. Vitamins in bacteria, isolated from the larval rearing tank were also analysed, as they can also contribute to the diet. Vitamin B₁₂, -tocopherol and -carotene were detected in very low concentration in bacteria; however, some bacterial strains were rich in pantothenic acid, and the pattern of other vitamins was similar to that from microalgae. The presence of bacteria can complement the diet in panthothenic acid, as it has been demonstrated that bacteria are ingested by larvae. The vitamin content of Pecten maximus larvae was analysed from the second day after hatching to just before metamorphosis. The content of some vitamins, ascorbic acid (C), -tocopherol and -carotene, increased during larval development, suggesting that their requirement was satisfied. However, thiamin and riboflavin decreased during larval development and further studies, possibly using microencapsulated vitamins supplements, are needed to determine whether these vitamins are limiting during larval development.     

罗氏沼虾对维生素C的需求

以每公斤饲料分别添加０、５０、１００、２００、４００、８００ｍｇ维生素Ｃ多聚磷酸酯（ＬＡＰＰ）的半纯化饲料饲养初始体重约５．５２ｇ的罗氏沼虾Ｍａｃｒｏｂｒａｃｈｉｕｍｒｏｓｅｎｂｅｒｇｉ９周。结果表明,添加ＬＡＰＰ使罗氏沼虾的相对增重率显著升高,蜕壳频率增加,蜕壳周期缩短。添加量达到５０ｍｇ／ｋｇ的,可以保证罗氏沼虾正常蜕壳。肝胰脏和血淋巴中的Ｖｃ含量随饲料中ＬＡＰＰ水平的上升而上升,ＬＡＰＰ的添加量达２００ｍｇ／ｋｇ时,肝胰脏中的Ｖｃ达到饱和;而血淋巴中的Ｖｃ含量则随饲料中ＬＡＰＰ水平的上升一直上升。若饲料中缺乏ＬＡＰＰ,则罗氏沼虾全虾的蛋白质和粗脂肪含量下降,而肝胰脏中的粗脂肪含量上升。以增重率为指标,用突破点直线回归法确定罗氏沼虾饲料中Ｖｃ多聚磷酸酯的适宜含量为１１１．９ｍｇ／ｋｇ。     

Vitamin C Requirements of the Angelfish Pterophylum scalare

Abstract.— Despite a large economical value of the ornamental fish trade, little information is available on the dietary ascorbic acid requirements of these species. Ascorbic acid requirements of fishes of the cichlid family appear to vary widely. Juvenile angelfish, a widely produced ornamental cichlid, were maintained on diets containing graded levels of ascorbyl monophosphate. Liver ascorbic acid concentrations after 96 d of feeding were significantly reduced in groups receiving 120 mg or less ascorbic acid equivalents/kg diet. However, no differences in growth or mortality between groups were found, and no external signs of ascorbic acid deficiency were observed, indicating a high resistance of this species against prolonged ascorbic acid deficiency. Based on the long possible life span of angelfish in the aquarium, we proposed a conservative dietary ascorbic acid requirement of 360 mg/ kg diet, necessary to maintain maximum tissue storage of this vitamin.     

Vitamin A functions and requirements in fish

Vitamin A (VA) is an essential dietary nutrient for fish and plays an important role in a range of physiological processes including vision, reproduction, embryogenesis, growth and differentiation and maintenance of epithelial cells. Knowledge of effects of VA on aquatic organisms is limited, but new information continues to be published. The aim of the present review is to present an overview of the dietary requirements and functions of VA in fish of commercial importance in aquaculture production. The effects of VA on reproduction and early embryonic development are described, and the estimated dietary requirements for VA of several species of fish are discussed. New research findings on how VA requirements vary with the life stages of fish are explored that will expand understanding of the complex role of VA. Sources of VA in feeds are described, and the potential need to consider how changes in fish feed formulations towards higher use levels of sustainable ingredients may affect dietary VA supplementation recommendations is discussed.     

维生素C对视黄醇结合蛋白基因作用的初探

采用半定量RT-PCR方法研究了在体外培养的猪成纤维细胞内,添加0.5,5,10,30μg/μL浓度的维生素C后,分别作用12、24、48和72h后,视黄醇结合蛋白基因(RBP4)的表达变化情况。结果表明:维生素C可显著抑制RBP4基因的表达。     

Vitamin C deficiency in the catfish Clarias gariepinus

Regardless of the absence of spinal deformities, vitamin C deprivation in adult-sized Clarias gariepinus challenged the physical integrity and survival of fish, inducing changes that greatly resembled those of fingerlings of other species. Vitamin C was presumed to be a dietary facilitator, which when deprived in the diet of C. gariepinus , would obstruct intestinal absorption of iron and/or impair its release from the reticulo-endothelial stores. This impaired erythrocyte synthesis led into anaemia (as indicated by lowered levels of red blood cells, haemoglobin and haematocrit). Leukopenia noted in fish on a scorbutic (lacking vitamin C) diet suggested functional depression of phagocytic engulfment with increased susceptibility to the deteriorating action of pathogenic agents. Changes in histology included hypertrophy, oedematous separation and telangiectasia of gill lamellae. Shrunken glomeruli, sloughed Bowman's capsules and tubular dilation and distortion were also shown. Shrunken hepatocytes and the occurrence of yellowish ceroid pigments were the concrete histopathological signs in liver. Vitamin C is thus suggested as a potent antioxidant that offers protection against oxidative damage to various fish tissues.