首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
鲍人工饲料研究新进展   总被引:5,自引:1,他引:5  
本文综述了国内外鲍人工饲料研究与生产应用的水平与现状,对配合饲料中主要营养物质的要求、添加剂与粘合剂等亦作了全面介绍。  相似文献   

2.
3.
4.
饵料对锯缘青蟹大眼幼体生长发育的影响   总被引:3,自引:0,他引:3  
以不同比例的轮虫和卤虫无节幼体搭配成各种饵料组合,分别喂养不同发育期的锯缘青蟹幼体,重点研究大眼幼体的存活、生长发育、变态和干重及化学元素(C、H、N)含量的情况.结果表明饵料搭配得当,适时适量的投喂,其幼体的生长发育和变态都正常,并可获得较高的存活率,若饵料搭配不当不仅会导致幼体出现高死亡率,而且还能诱发发育期变化的现象;不同饵料搭配对大眼幼体干重及化学元素(C、H、N)含量的影响很显著,相差60%~70%,约一个发育期,而这差异可以通过该期幼体投喂足量卤虫无节幼体来加以弥补,大眼幼体的C、H、N占干重的百分比仅次于溞V,这表明青蟹幼体在这两次变态前需在体内积累高比例的有机营养物质来保证变态的顺利进行.  相似文献   

5.
Notolabrus fucicola Richardson, a large common labrid inhabiting shallow waters around New Zealand and southern Australia, were collected monthly (December 1996‐February 1998) around Kaikoura on the east coast of the South Island, New Zealand. Their diet, temporal variation in prey and gut fullness, and ontogenetic differences were examined. N. fucicola is a generalist predator, the major prey items being bivalves, amphipods, and crabs, which varied temporally in their diet. There were size specific changes in their diet. Small fish (100–180 mm) ate mostly amphipods and isopods, whereas larger fish (> 180 mm) ate mainly bivalves, crabs, and gastropods. There was a temporal variation in gut fullness but no significant difference between sexes.  相似文献   

6.
分别用亚心形扁藻Platymonas subcordiformis、球等鞭金藻Isochrysisgalbans、亚历山大藻Alexandriumspp.、新月菱形藻Nitzschiaclosterium、赤潮异弯藻Heterosigmaakashiwo为饵料,研究安氏伪镖水蚤Pseudodiaptomusannandalei(Sewell,1919)的产幼量,在产幼期间,日平均产幼量分别为14.5、15.0、10.1、9.2和9.9个·d-1,平均持续产幼天数分别为12.0、9.0、12.6、7.7和3.1d。以日平均产幼数和持续产幼天数的乘积作为综合指标进行分析,结果表明亚心形扁藻综合指标值最大,但与亚历山大藻和球等鞭金藻之间无显著差异,亚心形扁藻和球等鞭金藻的差异显著高于赤潮异弯藻和新月菱形藻。赤潮异弯藻和新月菱形藻之间无显著差异。对安氏伪镖水蚤的日平均产幼量和平均持续产幼天数进行回归分析,得出一直线回归方程y=8.357 0.385x(p<0.0030),日平均产幼量和平均持续产幼天数有显著的正相关,表明优良的饵料不仅能提高安氏伪镖水蚤的日平均产幼量,而且能延长产幼期,说明饵料质量可显著地影响安氏伪镖水蚤的生殖力。  相似文献   

7.
Abstract.  Natural prey composition and prey selectivity of the muricid snail Muricodrupa fusca (Küster), which forages on a wide range of prey, was investigated. Natural prey composition was evaluated through correcting the apparent diet (the result of observations of the feeding behavior) by the handling time, which was determined by laboratory analysis. The apparent diet and the natural diet should generally differ because prey items that require a longer handling time will be observed with higher frequencies. Multiple regression equations were derived to relate the handling time to prey size, predator size and water temperature. A large discrepancy in the apparent versus natural diet of M. fusca was found in prey species composition and prey size. They foraged on at least 11 species of sessile and mobile prey including six limpet species, and mainly preyed on Siphonaria spp. and Lottia spp. in the field. By comparing the percentage of the natural diet to that of prey abundance in the field, M. fusca preferred Siphonaria spp. and Lottia spp. and did not select the other prey species. The selectivity of this predator was explained by optimal foraging theory and antipredator defenses of some limpet species. The relationships among attacking methods, handling time and prey selectivity are also examined.  相似文献   

8.
9.
养殖对虾病毒性疾病的细菌并发症防治研究   总被引:1,自引:0,他引:1  
苏国成  陈金翠 《台湾海峡》1996,15(2):200-204
本文研究报道了发病对虾肝胰腺分离菌物敏感性,采用防台细菌人工感染方法进行药物饲料的筛选,在实验室及养殖池中进行药物饲料的防治效果试验。结果表明,在对虾病毒流行期间,采用药物饲料可有效防止对虾爆发性大量死亡,提高对虾存活率。  相似文献   

10.
中国对虾配合饵料添加维生素的效果   总被引:1,自引:0,他引:1  
将维生素作为一个综合指标加以试验,配备5个不同维生素水平(0,0.27,0.54,1.1,2.1%)的饵料试验组,经较长期的室内饲养试验以考察混合维生素对对虾生长和成活率的影响。结果表明,在试验范围内,随着添加维生素份量的增加,对虾的成活率也增高,增重倍数也提高。这就表明,维生素(在试验范围内)有降低对虾死亡率、促进生长的作用。维生素促进生长的效应最敏感区间是0~0.54%,在此范围内,维生素的少量增加也能明显地提高其生长效果,而维生素在1.1~1.2%范围内,增重曲线就逐渐趋向平坦,表示2.1%的添加量接近维生素的最适添加量。 维生素还有降低饵料系数的作用,在试验范围内,随着维生素的增加,饵料系数也降低,最低可达2.48。  相似文献   

11.
12.
赤点石斑鱼人工配合饵料中蛋白质最适含量的研究   总被引:11,自引:1,他引:11  
本文探讨了不同蛋白质含量的配合饵料对赤点石斑鱼(Epinephelusakaara)生长的影响。通过60d度验得出:在各配合饵料组中,蛋白质含量为49.52%的试验的相对增重率(46.84%)体长相对增长率(15.96%)、蛋白质效率(60.35%)和饵料转化率(29.85%)等均为最佳。配合饵料组鱼体肌肉营养成分(蛋白质、脂肪、氨基酸和鲜味氨基酸)也均优于对照组,而更接近野生鱼。经回归方程分析,赤点石斑鱼人工配合饵料中蛋白质最适含量为48.37%~49.24%。  相似文献   

13.
中国对虾配合饵料中维生素C添加量的研究   总被引:9,自引:1,他引:9  
于1991年7月21日-8月19日在河北省唐海县西林养殖场以养成期中国对虾为材料,在其配合饵料中添加维生素C进行中国对虾对维生素C需要量的试验。结果表明,当中国对虾体长为5.5-7.5cm时,若以本项研究采用的配合饵料的基本成分和配比为基础,配饵中维生素C的最佳变化添加量为0.018%-0.030%。研究发现,变动的维生素C适宜添加量对于中国对虾具有明显的促进生长,增强抗病力和抗低氧能力以及提高存  相似文献   

14.
于2002年11月、12月共采集67尾黄海大头鳕,对其胃含物进行了初步分析。结果表明:大头鳕食物中出现的主要种类有鱼类、甲壳类、瓣鳃类、头足类、蛇尾类和海绵等六个生物类群,共22多种,其中主要有小黄鱼、方氏云鳚、大头鳕、脊腹褐虾、太平洋磷虾等。本文还对不同年份大头鳕食饵更替进行了探讨。  相似文献   

15.
Inter‐decadal and geographic variations in the diets of Steller sea lion, Eumetopias jubatus, were examined based on the contents of 408 stomachs collected from coastal areas around Hokkaido Island during the periods 1994–1998 and 2005–2012. The most important prey species in the 1990s were gadid fishes (walleye pollock [Gadus chalcogrammus], Pacific cod [Gadus microcephalus] and saffron cod [Eleginus gracilis]). The frequency of occurrence and gravimetric contribution of gadids decreased in the 2000s latter period at three study sites (Rausu, Shakotan and Rebun) and were replaced by Okhotsk Atka mackerel (Pleurogrammus azonus) and smooth lumpsucker (Aptocyclus ventricosus). However, analysis based on gravimetric composition indicated that the dietary diversity of prey showed only a slight inter‐decadal difference, reflecting the wide diversity of prey ingested during both study periods. These results indicate that Steller sea lions along the Hokkaido coast are opportunistic feeders that utilize a wide variety of prey, and appear to feed mainly upon prey that is easily obtained.  相似文献   

16.
中国对虾幼体发育阶段维生素A营养需要的研究   总被引:5,自引:0,他引:5  
1996年5月11日-6月13日中国在水产科学研究院黄海水产研究所麦岛实验基地采集中国对虾幼体,在其配合饵料中添加维生素A,对其发育阶段维生素A的营养需要进行研究。结果表明,配合饵料中维生素A的含量为40.16-6.15μg/g时,对中国对虾幼体的变态,成活和健康有明显的促进作用。  相似文献   

17.
The diet of the squid Nototodarus sloanii was determined from examination of stomach contents of 388 specimens of 14.3–41.0 cm dorsal mantle length sampled at depths of 211–760 m on the Chatham Rise, New Zealand. Prey items were predominantly mesopelagic fishes, with some crustaceans and cephalopods. The most important prey species identified was Maurolicus australis, followed by Lampanyctodes hectoris, and unidentified squids (Teuthoidea). Multivariate analyses using distance‐based linear models, non‐parametric multi‐dimensional scaling, analysis of similarities, and similarity percentages, indicated crustaceans were more important in the diet of smaller squid (83–480 g), the fish component of the diet was dominated by L. hectoris on the east Chatham Rise and M. australis on the west Chatham Rise, and there may be a difference in diet with sex, with crustaceans and cephalopods more important for females. The results indicated that N. sloanii, similar to other ommastrephid squids, foraged primarily in the mesopelagic layers.  相似文献   

18.
祝茜  姜波  汤庭耀 《海洋科学》2004,28(10):17-19
鲸具胎生、哺乳、用肺呼吸、体温恒定等典型哺乳动物的特征,由于终生生活在水中,体型庞大。要保持正常的体温和代谢活动。必须消耗大量食物来补充能量。因此,了解鲸的食性、摄食方式及其与渔业的关系就显得十分重要。按摄食方式的不同将须鲸划为过滤型,齿鲸为捕食型;按食物组成和摄食方法的不同,将齿鲸又分成三大类型:食乌贼型、食肉型和食鱼型;须鲸则为食浮游生物型。同时探讨了鲸类造成渔业的损失:直接摄食、毁坏渔具、妨碍作业、争食渔网内的渔获物、驱散鱼群造成鱼捕捞量降低等。渔业对鲸类的主要影响表现为:误捕、食物短缺和噪音等.  相似文献   

19.
The diets of several populations of four recently described species of galaxiid with allopatric distributions were examined in the Taieri River, New Zealand. Comparisons of available prey items and prey consumed were carried out to examine whether the distributions of the galaxiid species might be influenced by food availability and preferences. Seventy‐three prey categories were identified. The availability of four of these (Deleatidium, Oligochaeta, Elmidae larvae and adults) differed among the streams occupied by different galaxiid species. Three differences in the frequency of prey consumption (Deleatidium, Oxyethira, and Elmidae larvae) were detected. Despite differences in diet it was concluded that all four fish species were generalist predators of invertebrates with similar diets that were influenced mainly by prey availability. Furthermore prey availability was not considered responsible for the allopatric distribution of the four species, rather, spawning habitat availability, physical nature of the streams, and prior geological history of the Taieri catchment are considered the controlling influences on galaxiid distribution.  相似文献   

20.
The spatial size distribution of grunts and snappers have previously indicated the separation of juveniles in nursery habitats from the adults on the coral reef. This implies life cycle migrations from nursery habitats (such as seagrass beds and mangroves) to the coral reef. If diet shifts are related to such migrations, then the diets of these fish must change before or around the fish size at which such migrations take place. A wide size range of juveniles of two grunt species (Haemulon sciurus and Haemulon flavolineatum) and of two snapper species (Lutjanus apodus and Ocyurus chrysurus) were caught in seagrass beds and mangroves, and their gut contents identified and quantified. Regression analysis between fish size and dietary importance of small crustaceans showed a negative relationship in all four species. Positive relations were found for H. sciurus, L. apodus and O. chrysurus between fish length and the dietary importance of decapods, and for L. apodusand O. chrysurus between fish length and prey fish importance. Critical changes in the fish diets with fish size were examined by application of a Canonical Correspondence Analysis (CCA). The CCA yielded three clusters of size-classes of fishes with similar diets, and application of a Mantel test showed that each of these clusters had significantly different diets, and that each cluster diet was significantly specialised. The size at which a fish species ‘switched’ from one cluster to another was compared with size-at-maturity data and with the typical size at which these species migrate from the nursery habitats to the coral reef. H. sciurus and H. flavolineatum may be prompted to migrate from the nursery habitats to coral reef habitats because of dietary changes, or because of the development of the gonads. For L. apodus and O. chrysurus, a dietary changeover forms a more likely explanation for nursery-to-reef migrations than does sexual maturation because these species reach maturity at sizes much larger than the maximum size of individuals found in nursery habitats. Although other factors may theoretically initiate or promote the migration patterns, the results of this study indicate that ontogenetic dietary changes may crucially influence the nursery-to-coral reef migrations of these reef fish species.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号