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菜籽饼粕抗营养因子研究进展 总被引：12，自引：0，他引：12
总结了菜籽饼粕中日粮纤维、硫甙、植酸、单宁和芥子碱的化学构成与性质、在畜禽体内代谢过程、抗营养作用,分析了影响菜籽饼粕抗营养作用的因素,提出了消除和减轻抗营养作用的措施。 相似文献
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本文分析了福建省抗风浪网箱养殖的发展现状及存在的问题，提出了积极、稳妥地推进我省近海抗风浪网箱养殖产业化的对策与措施。即：(1)政府对抗风浪网箱制造企业、养殖龙头企业及相关企业、养成品销售市场等方面继续给予资金和优惠政策扶持，加快已发展网箱的投产速度；(2)鼓励“强强企业联合”，建立抗风浪网箱养殖基地，积极推行“网箱基地 养殖户”和“订单渔业”的抗风浪网箱养殖经营模式；(3)加大科研投入，尽快完善重力型沉浮式抗风浪网箱的技术性能，并开展阻流设施、换网机械、鱼规格分级设备、自动投饵设备等配套设施的后续研究，加速产业化进程；(4)开展全省抗风浪网箱养殖规划研究。 相似文献
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正在水产养殖业"减抗"呼声风起云涌的今天,在"推动健康养殖、保障食品安全"已成行业发展新潮流的必然趋势下,研发并寻找具有"减抗"甚至"替抗"功能的新产品或者方案已成当务之急。正是在这样一个时代背景下,越来越多的有识之士和企业不断加大研发投入力度,各种新的"减抗"增效类产品不断涌现,为推动行业健康、可持续发展增添了一个个新的强大助力。我们依托强大的医药研发团队,在"减抗"研发方面也不断前行。除 相似文献
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大型网箱起网设备及方法 总被引：2，自引：0，他引：2
我国海水网箱养殖始于20世纪70年代,但在开展深水抗风浪网箱方面的研究直到“九五”期末才开始,起步较晚。通过引进消化吸收,我国的多家科研机构成功地研制出深水抗风浪网箱设施,并迅速得到推广。目前各种深水抗风浪网箱在山东、浙江、福建、广东、海南等多个沿海地区建立了十几个深海网箱养殖示范基地,为抗风浪网箱养殖技术的推广积累了宝贵的经验。我国深水抗风浪网箱养殖技术的突破,更新了传统网箱的养殖模式,拓展了养殖空间,为促进我国海水鱼类养殖业的持续、健康、稳定发展做出了积极的贡献。 相似文献
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在草鱼饲料中加入抗应激添加剂(主要成分为棉粕酶解产物、金银花全花水提物和干酵母培养物)进行86 d的养殖试验,对草鱼的肌肉常规营养成分和免疫相关指标进行分析,以了解抗应激饲料添加剂对草鱼生长、免疫和抗应激能力的影响。试验结果:加入1 %添加剂的试验组在增重率、肌肉品质和抗应激能力方面均优于对照组。试验组鱼的增重率提高8.6 %,血清和肝胰脏中维生素E的含量分别提高29.15 %和39.14 %,血清中溶菌酶的含量提高31.78 %;试验组鱼的SOD、CAT、GSH在血清中的活性均比对照组显著提高,其中SOD提高57.8 %,CAT提高132.25 %,GSH提高139.40 %。试验结果表明:该抗应激饲料添加剂对提高草鱼的抗应激能力有一定的作用效果。 相似文献
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Cardiac,ventilatory and metabolic responses of two ecologically dissimilar species of fish to waterborne cyanide 总被引：1，自引：0，他引：1
Changes in heart rate, ventilatory activity and oxygen consumption were determined in trout (Salmo gairdneri) and brown bullhead catfish (Ictalurus nebulosus) during exposure to a steadily increasing concentration of waterborne cyanide selected to produce death in 8–9 hours for each species. The lethal cyanide concentration for the bullheads was an order of magnitude higher than for trout. Trout developed an immediate and gradually increasing bradycardia throughout the exposure period. Cyanide produced tachycardia in the bullhead followed by a gradual onset of bradycardia as the concentration of cyanide was raised. Pericardial injection of atropine (a muscarinic cholinergic antagonist) indicated that bradycardia in the trout was due initially to increased vagal tone but later due to the direct effect of cyanide on the heart. Hyperventilation in the trout persisted throughout the exposure period, although the rate and amplitude fluctuated and was variable between individual fish. During the last hour of exposure (highest cyanide concentration), ventilation was characterized by rapid, shallow breaths followed by a sudden respiratory arrest. The bullheads exhibited hyperventilation during the first 3 hours of exposure followed by a gradual, linear drop in ventilation rate and amplitude until death occurred. Cardiac and ventilatory responses in both species were attributed to stimulation of central and peripheral chemoreceptors by cyanide. Evidence is presented which suggests the initial response in the bullheads was due, at least in part, to gustatory stimulation by the cyanide. Oxygen consumption of the trout remained above pre-exposure levels for the majority of the test period. Oxygen consumption in the bullhead paralleled the changes in heart and ventilatory rates. Whole-body lactate levels of fingerlings of both species during cyanide exposure were measured to estimate the extent of anaerobiosis. Whole-body lactate levels were much greater in the bullheads than the trout, indicating a higher capacity for anaerobiosis, possibly due to a greater fuel supply. Overall, the trout responded to cyanide in a manner similar to that produced by environmental hypoxia whereas the bullheads experienced a gustatory stimulus which masked the hypoxia-like response. 相似文献
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Studies of epidermal papillomatosis in fish populations have only rarely focused on the intensity of the disease, i.e. the number and size of papillomas. Furthermore, the methods used to evaluate the intensity of papillomatosis have not been standardized. We tested the reliability of a method based on counting of scales covered by papilloma tumours in roach, Rutilus rutilus (L). In addition, we studied the frequency distributions of the number of scales covered by papillomas within populations, evaluated the correlation between the prevalence and mean intensity of the disease among populations and examined the intensity of papillomatosis in roach with respect to sex and size of fish. Reliability of the scale coverage method was high. Therefore, the method could offer an effective way to determine the intensity of papillomatosis in fish species with large scales. The frequency distribution of the scale coverage of papillomas was highly aggregated within all populations studied. The mean intensity of papillomatosis increased with the size of the fish and was higher in males than in females. However, there was no correlation between the mean intensity and prevalence of the disease among the 19 roach populations studied. 相似文献
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Effects of a mix of Bacillus sp. as a potential probiotic for Florida pompano,common snook and red drum larvae performances and digestive enzyme activities 
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下载免费PDF全文 M.R. Hauville J.L. Zambonino‐Infante J. Gordon Bell H. Migaud K.L. Main 《Aquaculture Nutrition》2016,22(1):51-60
This study examined the effect of a commercial mix of Bacillus sp. on survival, growth and digestive enzyme activities of Florida pompano, red drum and common snook. Larvae were fed either live feed enriched with Algamac 3050 (Control), Algamac 3050 and probiotics (PB), or the previous diet combined with a daily addition of probiotics to the tank water (PB+). Survival was not affected by the treatments for any of the species. At the end of the pompano and snook trial, standard lengths of larvae from the PB and PB+ treatments were significantly greater than for the control larvae. Microbiological analyses were performed at the end of the pompano trial, and numbers of presumptive Vibrio were not a concern in the system. For both pompano and snook, trypsin‐specific activity was higher in PB and PB+ larvae compared with the control larvae. Similarly, alkaline phosphatase activity was higher for the pompano larvae fed the PB and PB+ treatments and for the snook larvae fed the PB+ treatment compared with the control larvae. This experiment suggests that a mix of Bacillus sp. can promote growth through an early maturation of the digestive system during the early larval stages of pompano and snook. 相似文献
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C.A. Duigan T.E.H. Allott D.T. Monteith S.T. Patrick J. Lancaster J.M. Seda 《水产资源保护:海洋与淡水生态系统》1998,8(3):325-360
1. This paper gives a comprehensive account of the ecology of Llyn Idwal and Llyn Cwellyn, two nationally well known and internationally important conservation lakes in Snowdonia National Park, North Wales. Idwal has a small but precipitous catchment with relatively large areas of heathland and base rich bare rock. Cwellyn has a larger catchment with a substantial proportion of woodland, including coniferous plantations, and a long history of human activity. 2. The chemistry of the waters in both lakes is indicative of nutrient-poor conditions but Idwal exhibits relatively high alkalinity and pH values. 3. The diatom floras are typical of nutrient-poor upland waters, with species composition reflecting the alkalinity differences. Isoetids form a dominant component of the macrophyte floras, with the most diverse assemblage recorded at Idwal. 4. The zooplankton communities are distinctive, with only a small number of species occurring in both lakes. The macroinvertebrate faunas are dominated by insect taxa typical of stony shores. Supplementary stocking of the Idwal trout population has been reported. 5. The conservation importance of the sites lies primarily in their representation of nutrient-poor mountain lake systems and the macrophyte assemblages which include a number of rare species. In addition, a genetically unique arctic charr population is present in Cwellyn. 6. Impoundment, water abstraction, acidification, eutrophication and the recreational use of the sites are identified as potential environmental impacts. The conservation management of the sites is related to the extent of the reserve boundaries and catchment activities. Aspects of the future management and environmental monitoring of Idwal and Cwellyn as Special Areas of Conservation under the European Community Council Directive on the conservation of natural habitats and of wild fauna and flora are discussed. © 1998 John Wiley & Sons, Ltd. 相似文献
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We examined the element pattern in the otoliths of a migratory fish species that inhabit the coastal areas in the brackish of the Baltic Sea. The northern pike (Esox lucius) show migratory behaviour, spawning in streams and rivers and foraging in the sea. We examined spawning migration in four nearby streams in the south‐west part of the Baltic. Otolith analysis by microPIXE revealed unique elemental patterns (Sr, Zn, Br, Co and Mn) for the juveniles in each of the different streams. The strontium signal in the otolith of the juveniles was used as an indicator of freshwater origin and the time spent in the stream. Adult pike in their migrating spawning phase were caught in each of the streams. The elemental composition in otoliths in their freshwater phase (using juvenile pike in the streams as references) was determined. A principal component analysis showed that the elemental fingerprint during the freshwater phase several years back in time was similar for the adult fish and for juveniles inhabiting the stream today. The results indicated natal homing of the adults to a specific stream, a conclusion that was strengthened by the fact that marked fish returned to spawn over consecutive years. Anadromous pike in the Baltic Sea may thus be divided in subpopulations. The results of the study may have implications for fishery management, as pike in the Baltic Sea cannot be seen as homogenous population. 相似文献
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中国对虾对维生素B2、B5、B6营养需要的研究 总被引：5，自引：0，他引：5
研究了三种水溶性维生素Ｂ２，Ｂ５和Ｂ６在以酪蛋白为蛋白源的饲料中的不同含量对中国对虾的存活率，体重增重率，体长增长率，蛋白质消化率及实验维生素在体内的累积量等方面的影响。结果表明，在每１００ｇ饲料中维生素Ｂ２、Ｂ５和Ｂ６的含量分别在１０（体重１．５３ｇ）－２０ｍｇ（体重６．００ｇ）、４０ｍｇ、１４ｍｇ时，上述指标均达最佳，维生素缺乏或过量都会阻碍对虾生长，在适宜添加量范围中，随着饲料中维生素Ｂ６的 相似文献
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Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean 下载免费PDF全文
下载免费PDF全文 The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna. 相似文献
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报道了对中国对虾卵子激活反应的形态学研究。中国对虾卵子皮层中有由卵黄膜下陷形成的与卵表垂直的皮层囊,内有棒状结构称棒状周边体,其内物质为凝胶前体。对虾卵子的激活并不需要精子的发动,而是在卵子与海水接触后即开始进行。在卵子激活过程中,棒状周边体向外放出形成花冠状的凝胶层,然后从基部开始逐渐消失并向远端扩展,最后完全消失,同时卵子进行成熟分裂放出第一、第二极体,并举起受精膜,完成激活反应。还对中国对虾卵子激活的作用进行了讨论。 相似文献
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The growth of juvenile abalone in aquaculture is known to be affected by density as a result of competition for food and decreases
in water quality. Our results suggest that behaviour is also affected by density and this also has a significant impact on
the growth of individual abalone. 1800 juveniles of Haliotis rubra were individually tagged and reared for 5 months in 12 gravity-fed tanks at two levels of density. The experimental design
allowed the differentiation of the direct from the indirect effects of density. The abalone growth and distribution was monitored
monthly along with the water quality. The distribution of abalone during daytime was closely related to the availability of
preferred shelter space. The percentage of abalone stacked on the top of others increased with density. Preferred shelter
space was characterized by low light intensity and a corner or edge for the abalone to rest against. Hides at the ends of
the tanks were not occupied as much as others. Abalone were found crawling on the side of the tank during daytime when tanks
were shaded. Abalone juveniles of 15–60 mm showed fidelity to their resting shelter during daytime but this fidelity was significantly
reduced at the higher density. Shading of the tanks totally changed the distribution of the abalone and their daytime behaviour.
Competition for shelter space reduced growth more than water quality.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献