不同大豆蛋白源对黄金鲈蛋白酶及淀粉酶活力的影响

试验研究了不同种大豆蛋白源对黄金鲈消化系统的蛋白酶及淀粉酶活力的影响,为优化黄金鲈配合饲料提供依据。分别以豆粕和全脂豆粉为植物蛋白源,鱼粉为动物蛋白源,混合油脂(鱼油玉米油=11)为脂肪源,面粉和糊精为糖源,配制成3种等氮(粗蛋白质42.0%)、等能(总能20.0 MJ/kg)的半精致饲料,其中豆粕和全脂豆粉分别替代鱼粉的20%蛋白质。每组饲料设3个重复,每个重复放养20尾[(28.71±0.08)g/尾],在控温单循环养殖系统中进行为期8周的饲养试验。饲养试验结束后,分别采用福林酚试剂法及试剂盒测定黄金鲈胃、幽门盲囊、肝脏及肠道蛋白酶及淀粉酶的活力。在本试验条件下,黄金鲈配合饲料中,当豆粕替代鱼粉蛋白的20%时,黄金鲈的幽门盲囊、肝脏、前肠及中后肠蛋白酶活力与对照组差异不显著(P0.05),而胃蛋白酶活力显著低于对照组(P0.05);当全脂豆粉替代鱼粉蛋白质的20%时,黄金鲈的胃、幽门盲囊、肝脏、前肠及中后肠蛋白酶活力显著低于对照组(P0.05)。但在黄金鲈配合饲料中,豆粕和全脂豆粉分别替代鱼粉蛋白质的20%时,对其胃、幽门盲囊、肝脏、前肠及中后肠淀粉酶活力的影响不显著(P0.05)。基于大豆蛋白源对黄金鲈消化系统的蛋白酶及淀粉酶活力的影响,在鱼粉20%的蛋白质替代水平下,豆粕的替代效果优于全脂豆粉。     

内蒙古鄂尔多斯市引进名特优鱼类高密度流水混养试验

在内蒙古鄂尔多斯市开展细鳞鱼、哲罗鲑、虹鳟、白点鲑4种名贵冷水鱼的高密度流水混养试验,对饲养过程中的关键技术指标和养殖效益进行考察和分析,以期为调整该地区水产品养殖品种结构,探寻适合该地区养殖的名特优水产品品种和相应的技术方法提供科学依据。     

洛氏鱥的研究现状及养殖发展前景

洛氏鱥(Phoxinus lagowskii Dybowski)为我国土著江河野生的杂食性小型经济鱼类,具有肉质细嫩、味道鲜美、营养价值高、适应范围广、抗病力强、耐低氧等特点,是一种很受市场欢迎的名贵鱼类。本文在查阅国内外相关文献报道的基础上,介绍了洛氏鱥的生物学特性、研究方向及发展前景。旨在为洛氏鱥的健康养殖及调整我国水产养殖品种结构提供参考。     

鸭子的故事（上）

出身名门“草原鸭” 在世界的鸭种系统里，有一个名贵品种，那就是英国的樱桃谷鸭。樱桃谷并不是一条开满樱桃花的幽静山谷，它是英国一家著名养殖公司的名字。     

大弹涂鱼池塘养殖技术

近年来,大弹涂鱼池塘养殖在广西合浦沿海悄然兴起,大弹涂鱼市场价格昂贵,是一种值得推广养殖的名贵品种。 一、生物学特征 大弹涂鱼又称跳鱼、花跳、粉跳、泥牛、星点斑星鱼,是温带沿海小型经济鱼类。大弹涂鱼为广盐性鱼类,常栖息于底质为烂泥的低潮区或半咸水的河口滩涂,穴居,匍匐跳跃于泥涂上觅食。体     

名贵观赏鱼锦鲤的养殖技术

锦鲤是鲤鱼突变品系经人工选育而成的一种名贵观赏鱼类,其游姿高雅,体型优美,色彩艳丽,斑纹灿烂,具有较高的观赏价值,深受人们的喜爱,市场看好,养殖趋热,是目前在发展观赏鱼养殖业中销往欧洲市场一个可创汇的主要品种.其养殖技术要点如下:     

澳洲鳕鲈引种驯化养殖的报告

虫纹鳕鲈属鲈形目,暖鲈科,鳕鲈属,是澳大利亚南部墨累河水域具有很高营养价值和经济价值的游钓、商业性生产和资源增殖的地方名贵品种,有澳大利亚国宝鱼的美称。澳洲鳕鲈生长速度相对较快,比较适合在我国进行养殖,     

罗氏沼虾养殖技术

罗氏沼虾杂食性,生长快,其味道鲜美,营养丰富,是一个很好的淡水养殖品种.据分析,虾肉含蛋白质18.27%,脂肪1.97%,其蛋白质中含8种氨基酸,是深受广大群众欢迎的名贵水产品.养殖罗氏沼虾具有广阔的发展前途,是广大渔(农)民致富的一门新兴产业.     

加州鲈商品鱼池塘养殖技术

加州鲈属广温肉食性淡水名贵鱼类，具有适应广、生长快、病害少、易起捕，肉味美、营养价值高，市场前景好等特点，是发展池塘高效养殖的重要经济鱼类之一。同时，因该鱼较贪食，易上钩，又是发展游钓渔业的好品种。为此，本文简要介绍加州鲈商品鱼池塘养殖和常见病防治技术。     

珍贵的裘用品种羊

珍贵的裘用品种羊＠金江珍贵的裘用品种羊金江我国羊资源丰富。有很多是世界上稀有的珍贵品种，这些名贵品种羊的羔皮、裘皮及羊毛、羊绒等是出口创汇的传统商品，享誉全球。１．滩羊：是我国独有的名贵白色裘用绵羊品种。主要分布在宁夏回族自治区中部地区、内蒙以及甘肃、陕西...     

Experimental Transmission of Walleye Dermal Sarcoma to Yellow Perch

Abstract

Walleye dermal sarcoma was transmitted under experimental conditions to yellow perch Perca flavescens. Fish (20 weeks posthatch) were challenged with cell-free tumor filtrates by topical application on the right flank and then held for observation for 25 weeks in 15°C dechlorinated municipal water. Additional treatment groups included yellow perch challenged with cell-free filtrates of walleye discrete epidermal hyperplasia, yellow perch discrete epidermal hyperplasia, normal yellow perch skin (control), and normal walleye skin (control). Walleye dermal sarcoma was first observed on yellow perch at 20 weeks postexposure, at which time the tumors were small (1–2-mm), slightly raised masses on the right flank of the fish. At the end of the 25-week study, walleye dermal sarcoma was grossly observed in 42% (22 of 53) of the remaining fish and was confirmed by microscopic examination in an additional 29% (9 of 31). Gross and microscopic evaluation of fish at 25 weeks postexposure did not reveal development of lesions in any of the other treatment groups. This study extends the host range of experimentally transmitted walleye dermal sarcoma virus to include the yellow perch.     

植物蛋白源替代鱼粉对鱼类机体氧化胁迫的研究进展

合理的开发与利用植物蛋白源已成为解决鱼粉全球性缺乏的重要途径之一。较高比例的植物蛋白源会导致鱼体承受的氧化胁迫加剧,进而造成机体损伤,影响鱼类对植物蛋白源的利用效率。文章对已开展的研究结果进行归纳、分析与讨论,旨在为提高鱼类对植物蛋白源利用研究开拓新的思路。     

The relationship between Adirondack lake pH and levels of mercury in yellow perch

Levels of total mercury in yellow perch Perca flavescens from Adirondack lakes were studied in relation to characteristics of the lakes to determine why some lakes had fish with higher concentrations of mercury. Almost all mercury in fish is in the form of methylmercury, which can pose significant health hazards to humans who consume such fish. Fish mercury concentrations and water chemistry data were analyzed from eight Adirondack lakes. Four lakes (Halfmoon Lake, Sand Pond, Rock Pond, and Upper Sister Lake) had pH values of less than 5.0. Four other lakes (Lake Adirondack, Kings Flow, Harris Lake, and Lake Kushaqua) had pH values of more than 7.0. The acidic lakes also had high levels of aluminum and low acid-neutralizing capacity relative to the neutral lakes. Yellow perch (n = 100) from the acidic lakes had significantly higher levels of mercury than did those (n = 102) from the neutral lakes (P < 0.001), and the total mercury concentration increased with both length and weight of the fish. We conclude that the pH of the lake water is a major factor in determining the concentration of methylmercury in yellow perch.     

Evaluation of 1-stage and 2-stage selection in yellow perch I: genetic and phenotypic parameters for body weight of F1 fish reared in ponds using microsatellite parentage assignment

Two selection methods, 1-stage selection (OSS) and 2-stage selection (TSS), for improving efficiency and profitability of selective breeding of yellow perch were evaluated, through examining the genetic and phenotypic parameters for BW of F(1) fish using microsatellite parentage assignment in this study. Approximately 94% of the sampled yellow perch progeny were assigned to single parental pairs using 8 microsatellite markers, which confirmed the applicability of the communal rearing technique in yellow perch breeding. Within OSS, the genetic correlation between 1-yr-BW and 2-yr-BW was high (0.98), indicating that the growth of yellow perch recorded at yr 1 could predict their growth for yr 2. Also mean family BW and family EBV for BW between yr 1 and 2 were found to be significantly correlated, suggesting yr 1 fast-growing yellow perch families continued to be the fast growing families in yr 2. Two-year random fish undergoing TSS were significantly heavier (P < 0.01) than those undergoing OSS. In addition, top males and females with TSS were heavier (P < 0.01) than those with OSS. Based on these results we concluded that the TSS was more desirable and effective for yellow perch breeding compared with OSS in terms of improving selection efficiency and reducing costs.     

Correlation of parasites with growth of yellow perch

The possible influence of parasites on the short-term and long-term growth and condition of yellow perch Perca flavescens was examined by investigating correlations between parasite abundance and specific growth variables. The following parasites were enumerated in age-1 yellow perch collected from Lake St. Pierre in June 2008: Apophallus brevis, Diplostomum spp., Ichthyocotylurus spp., Tylodelphys scheuringi, Phyllodistomum superbum, and Raphidascaris acus. Short-term growth was estimated using RNA/DNA ratios and long-term growth via the total length and condition as measured by the Fulton index. No correlation was found between parasite abundance and short-term growth, but a negative influence of combined infections of T. scheuringi and P. superbum on long-term growth was detected. In addition, the abundance of Ichthyocotylurus spp. was positively correlated with the condition of the yellow perch. Together these results suggest that limited or subtle pathogenic effects in juvenile fish are not discernable in recent growth but only in long-term growth indices. Furthermore, in future studies examination of parasite effects on fish growth should account for multiple infections.     

State of the art and future trends of European and Italian aquaculture

This paper describes the main features of fish aquaculture in Europe and Italy focusing attention on single sectors of the farmed species and their trend for the future. Over recent years, European and Italian aquaculture have shown a markedly different trend from that of world aquatic production. Asia, particularly China, has recorded a constant and rapid growth and Latin America a moderate development. Nowadays, European farmers are concerned with adapting their product to market demand and diversifying the fish species reared. After a discussion about the main European production statistics regarding finfish aquaculture production, we consider the most important aspects in the promotion of production and consequent consumption of farmed fish.     

Selective breeding in fish and conservation of genetic resources for aquaculture

To satisfy increasing demands for fish as food, progress must occur towards greater aquaculture productivity whilst retaining the wild and farmed genetic resources that underpin global fish production. We review the main selection methods that have been developed for genetic improvement in aquaculture, and discuss their virtues and shortcomings. Examples of the application of mass, cohort, within family, and combined between-family and within-family selection are given. In addition, we review the manner in which fish genetic resources can be lost at the intra-specific, species and ecosystem levels and discuss options to best prevent this. We illustrate that fundamental principles of genetic management are common in the implementation of both selective breeding and conservation programmes, and should be emphasized in capacity development efforts. We highlight the value of applied genetics approaches for increasing aquaculture productivity and the conservation of fish genetic resources.     

氧化鱼油对鱼类健康的危害及其作用机制的研究进展

鱼油作为脂肪源广泛应用于水产养殖中,但鱼油氧化后危害巨大。本文综述了近些年来国内外有关氧化鱼油、鱼油氧化后对鱼类的危害(生长性能、抗氧化功能、肌肉品质及组织结构)及其作用机制的研究进展,旨在为今后深入解析鱼类抗氧化机制以及通过抑制氧化鱼油的负面影响途径开发新型抗氧化剂提供理论基础,进而推动水产养殖业的健康发展。     

State of the art and future trends of European and Italian aquaculture

This paper describes the main features of fish aquaculture in Europe and Italy focusing attention on single sectors of the farmed species and their trend for the future. Over recent years, European and Italian aquaculture have shown a markedly different trend from that of world aquatic production. Asia, particularly China, has recorded a constant and rapid growth and Latin America a moderate development. Nowadays, European farmers are concerned with adapting their product to market demand and diversifying the fish species reared. After a discussion about the main European production statistics regarding finfish aquaculture production, we consider the most important aspects in the promotion of production and consequent consumption of farmed fish.     

黑水虻蛋白在海水鱼养殖业中替代鱼粉的应用概况

近年来,我国水产养殖业发展迅速,尤其是海水鱼养殖业,呈现出逐年增长的态势.然而作为主要饲用蛋白质来源的鱼粉,由于诸多因素已经不能满足水产养殖业的快速、可持续发展的要求.本文总结了国内几种常见海水鱼养殖中,使用黑水虻虫粉替代鱼粉的案例及应用效果,旨在为今后海水鱼养殖中,黑水虻饲用价值的开发与综合利用提供相关的研究思路.