基于计算机视觉的大菱鲆鱼苗计数方法研究

对单帧大菱鲆鱼苗计数时,由于鱼苗的重叠,导致图像中的鱼苗粘连。为此采用计算机视觉的方法,提出了一种基于曲线演化的图像处理方法来解决鱼苗图像粘连问题,并完成对鱼苗的准确计数。将图像预处理后的二值化鱼苗粘连图像的轮廓曲线作为初始演化曲线,通过水平集方法对曲线进行常值演化,统计演化过程中最大轮廓曲线数作为鱼苗数量。对选取的10帧粘连比较严重的二值化鱼苗图像分别采用面积法、连通域法、曲线演化法进行分离计数研究。结果表明:曲线演化法在鱼体数目增多时仍有很好的分离计数效果,有利于使用数鱼机对鱼苗进行准确计数。     

鱼苗计数中的骗局

每年渔农都要根据自己的养殖需要购入鱼苗,从几千尾到数万尾不等,鱼苗的计数是每年购买鱼苗过程中必做的一项工作。但是鱼苗细小又多,要做到鱼苗的准确计数很难。有些不法商贩和鱼苗繁殖场往往利用渔农的麻痹大意和这方面知识的欠缺,采用种种方法欺骗渔农,给养殖户带来了一定的经济损失,更重要的是影响了一年的养殖计划。下面就此进行一些介绍,以引起渔农的注意,谨防上当受骗。一、鱼苗计数的常见方法第一步。一般是把鱼苗拉起后放入鱼苗网或专用网箱中,剔除伤苗、死苗和杂物等。截取一段鱼苗网,把其中的鱼苗集中于网或网箱的一角,慢慢搅动,…     

日本研制成鱼苗计数器

日本中部电力公司综合技术研究所研制成了画象处理系统和微处理机相结合的鱼苗计数器。以前，真鲷、黑鲷等鱼苗用烧杯等容器计数。每4—5尾一数，一万尾鱼苗两个人计数需半天，误差10-30％。现在研制的鱼苗计数器是由电视摄象机、映象存储器、微处理机及打印机组成。电视摄象机摄取的鱼群映象信号，以高速进行A／D转换。     

在池塘中利用豆粕型饲料培育青鱼鱼种的试验

在黑龙江省哈尔滨市进行了青鱼示范养殖试验,旨在对利用美国大豆协会的80:20池塘养殖模式和豆粕型饲料养殖青鱼从鱼苗至鱼种的可行性作出评价.试验鱼放养在3口5亩(0.33公顷)大小的池塘内,放养密度为青鱼苗4000尾/亩,并搭配放养白鲢鱼苗1000尾/亩(即青鱼苗60000尾/公顷和鲢鱼苗15000尾/公顷).     

确定多通道鱼苗计数器通道数的方法

鱼苗计数是一项直接影响科学管理和经济效益的重要技术工作.但到目前为止,各国研制的单通道式鱼苗计数器和应用了微处理机的鱼苗计数机,都存在计数精度和计数速度相互制约的问题,如为了提高计数精度,必须相应地降低计数速度(即减小载苗水中的鱼苗密度),因此难以达到实用要求.为兼顾计数精度和计数速度这两项指标,可行方案是采用多通道计数方式,而设计该类计数器的关键问题,是合理选定通道的数目.本文较详细地阐述了确定通道数的有关理论和方法,以及所达到的实际效果.     

循环水人工繁育鳜鱼试验

在水源不好的原"四大家鱼"繁殖场,以20 556.5 m2的水面建立微循环系统,通过物理与生物净化后,使水质符合鳜鱼的人工繁殖和苗种培育要求,然后进行生产试验,共计繁育鳜鱼水花220万尾,其中销售开口鱼苗150万尾,其它大规格的鱼苗40万尾,创利润10.5万元.     

几种海水鱼类人工育苗的研究

进行了红鳍笛鲷、紫红笛鲷、斜带髭鲷、美国红鱼、尖吻鲈、卵形鲳堃等10种海水鱼人工育苗的研究，试验共计32次，培育出了一定数量的鱼苗，其中尖吻鲈鱼苗391万尾，布氏鲳堃鱼苗88万尾，卵形鲳鱼堃苗23万尾，红鳍笛鲷鱼苗0．5万尾，花尾胡椒鲷鱼苗10．7万尾，斜带髭鲷鱼苗20．1万尾，大黄鱼鱼苗56万尾，美国红鱼鱼苗234万尾，其平均成活率分别为83％、49％、58％、0．1％、14％、6％、42％、48％。对各种鱼类的人工育苗进行了对比、分析，对海水鱼类人工育苗的方法及目前育苗过程中存在的一些问题进行了讨论，试验表明：海水鱼类的人工育苗与藻类、海水比重等因素存在着密切的关系。     

鳜鱼冬片鱼种高产高效培育试验

永新县在1988-2001的十几年问每年销售四大家鱼水花鱼苗在1亿尾以上.近年销量骤减平均不到1000万尾.每年有大批的水花鱼苗滞销.因此我们在永新县鱼种场进行了鳜鱼高产高效鱼种培育试验.     

基于计算机视觉的鱼苗自动计数系统研究

为了在鱼苗的饲养、运输和销售过程中对一定数量或批量的幼苗进行精确计数,提出了一种基于计算机视觉的鱼苗自动计数系统。利用流体力学中伯努利原理(Bernoulli principle)设计了一个稳定流速的稳流水箱,使鱼苗和水一起以平稳恒定的速度流过过流计数箱体的拍摄区;使用电荷耦合元件(CCD)高速摄像头以与水流速度成比例的帧速采集图像,并传送给计算机进行图像处理;对图像进行阈值分割和目标提取后,计算出每帧图像中不重叠区域的幼苗数量,累加求得幼苗总量。结果表明,该系统计数的相对误差在15%以内,具有较高的精度。该研究不仅解决了目标粘连、连续计数和重复计数的问题,还可推广到虾苗、蟹苗等生物幼苗计数,具有通用性强、可行性好、推广范围大的特点。     

各地简讯

山东烟台地区鱼苗生产喜获丰收在毛主席无产阶级革命路线指引下,烟台地区家鱼人工繁殖鱼苗数比去年又有增加,至七月十日全区已孵化鱼苗10323.7万尾。特别是,各县库区的广大群众,发扬自力更生艰苦奋斗的革命精神,认真贯彻“三自三就”方法,积极进行人工繁殖鱼苗,取得显著成绩。栖霞县庵里水库原分配500万尾的     

Shrimp egg counting with fully convolutional regression network and generative adversarial network

Accurate egg counting is the basic demand in the hatcheries of the aquaculture. However, the time-consuming, fallible manual counting is now still adopted in most situations. Also, many traditional automatic egg counting methods cannot provide enough high efficiency and accuracy, especially in densely-distributed cases. In this paper, we propose a novel convolutional neural network (CNN) based method for shrimp egg counting. Compared to traditional methods mainly based on contour detection or image segmentation, the proposed method exploits the density map regression and is more efficient in densely-distributed case even with severe occlusion. Firstly, a new dataset of the redclaw crayfish Cherax quadricarinatus eggs is collected, which includes 450 images with about 272,000 eggs annotated accurately. Also, a synthetic dataset generation method based on generative adversarial network (GAN) is proposed to avoid the onerous manual labeling, and has potential applications in the supervised learning for the densely-distributed eggs or larvae counting. Then, considering the advantages of no manual preprocessing and fine-grained feature extraction in CNNs, a shrimp egg counting network (SECNet) based on fully convolutional regression network (FCRN) is proposed to realize the counting through regressing the input image into its density map. The test results show the average counting accuracy of the proposed SECNet can be up to 99.2 % when the SECNet is pre-trained on the synthetic dataset and finetuned on the collected dataset. Finally, a simple and cheap computer vision based counting setup is built by using three off-the-shelf devices and a convenient operation program integrated with the SECNet is developed for a person computer, which provides an accurate, real-time, and highly-efficient egg counting way.     

Sperm concentration in the mussel <Emphasis Type="Italic">Mytilus edulis</Emphasis> L.: a spectrophotometric measurement protocol

Quantifying spermatozoa concentration in milt samples is very important for aquaculture purposes, particularly when equal numbers of gametes are needed for experimental purposes, and different methods can be used. Haemocytometer and Coulter counting are the most precise methods to count spermatozoa, but they are very difficult to use when large numbers of samples are involved. A standard curve of spectrophotometric absorbance (A) against sperm concentration ([S]) was used herein instead, and an equation for estimating spermatozoa concentration for the mussel Mytilus edulis L. was obtained. The best wavelength to measure mussel spermatozoa was 320 nm, with a precision two or three times higher than at other wavelengths. The equation for spermatozoa concentration was A = 8.592 × 10⁻⁵ [S] + 0.0190 (r ² = 0.9979). Recommendations for choosing the best wavelength are discussed.     

褶皱臂尾轮虫对提高暗纹东方鲀鱼苗成活率的作用

利用褶皱臂尾轮虫和暗纹东方鲀鱼苗在5‰的咸淡水中都能够存活的特点,用面包酵母培育褶皱臂尾轮虫经海水小球藻强化培育后在5‰的盐度条件下投喂暗纹东方鲀鱼苗,结果表明,褶皱臂尾轮虫较之淡水轮虫可使暗纹东方鲀鱼成活率显著提高。     

山女鳟人工受精孵化技术初步研究

从日本引进的山女鳟发眼卵育成亲鱼后,以挤腹法采孵,取精,干导法人工受精,经30－60分钟止水膨胀后入桶式孵化器进行流水孵化,发展率25．2％,孵化稚鱼畸形率5．1％,患脐囊白点症的占7．3％,稚鱼体质软弱,受精后1－分钟内采用免膨法将卵将卵直接入桶孵化,发眼率59．4％,孵化稚鱼98％以上发育正常,畸形率3．6％,水质澄清孵化水温12℃试验组发眼率95．1％,孵化率94．0％,孵化稚鱼体质良好。     

Cadmium alters the reproductive endocrine disruption and enhancement of growth in the early and adult stages of Oreochromis mossambicus

Heavy metal cadmium (Cd) traces are able to promote growth (growth promoter) and induce early maturation in Oreochromis mossambicus fries of both sexes, whereas, in the adults, they degenerate the gonads and their function. The gathered data on length–weight relation, gonado-somatic index, hepato-somatic index, egg numbers and reproductive hormones such as gonadotropins (GtH-I and GtH-II) and gonadial hormones such as progesterone, testosterone and estradiol levels all prove Cd as an endocrine disruptor.     

黑鲷土池育苗与浮游动物的关系

据分析:三个土池的浮游动物常出现的有12个种类,以数量和出现的频率来划分,主要以桡足类为主,其次为多毛类、(虫虎)螺、贝类的D型幼虫。桡足类个体在0.5mm以下的分别为2~#土池约占53％:3~#土池占4B.8％;6~#土池占40.7％。鱼苗成活率以2~#土池最高达10.1％:其次为3~#土池达6.61％;最低的是6~#土池达5.83％。生长速度以3~#土池最快,全长为 3.44 cm;6~#土池全长为 2.97 cm;2~#土池最慢,全长为 2.54 cm。     

重金属对草鱼胚胎及鲤鱼苗的毒性研究

Hg、Cd、Cu、Zn四种重金属，按国家渔业水质标准所规定浓度为基数，配成超标5、10、20、50、100倍的单因子、双因子、三因子、四因子实验组。以水体染毒法对草鱼胚胎发育和鲤鱼苗进行毒性实验。结果表明：四种重金属均对鱼胚和鱼苗有致畸变和致死的毒性作用。其毒性强弱在指标倍数相同情况下顺序依次为：Cu)Zn)Cd)Hg。超标5倍的单因子重金属均影响鱼胚孵化。超标50倍以上绝大多数鱼胚（自原肠－鳔形成期）和鱼苗7天内致死率达100％。多因子重金属混合液比单因子都显示毒性加强。但有些因子混合液中也出现毒性减弱的拮抗现象。     

三种不同方式培育匙吻鲟苗种的研究

从湖北引进匙吻鲟（Polyodon spathula）水花6万尾，平均全长1．8cm，平均体重0．023g，苗体活泼健康。将它们分成三组，每组2万尾，分别采用三种不同的方式进行为期50d的精心培育。其结果为：试验A组中鱼苗平均全长达11．7cm，平均体重为16．127g，成活率为17．6％；试验B组中鱼苗平均全长达14．3cm，平均体重为18．575g，成活率39．6％；试验C组中鱼苗平均全长达15．5cm，平均体重为19．213g，成活率59．3％。试验C组采用的方法：在水泥培育池内培育至3．Oem～4．Ocm后，移入土池继续采用枝角类等浮游动物为饵料培育至平均全长为7．Ocm～8．Ocm后，再采用配合饲料进行转饵驯化的方式，是进行匙吻鲟苗种培育的一条较佳技术路线。     

An automatic counting system for transparent pelagic fish eggs based on computer vision

Alive eggs of marine species with pelagic eggs float, while dead eggs usually sink. A non-invasive method for counting the number of floating eggs therefore gives the possibility to track survival throughout experiments. In this paper we present an automatic image analysis method for counting live pelagic eggs of marine fish. Pelagic fish eggs are typically transparent and difficult to detect in images. Current image analysis methods for counting pelagic fish eggs are therefore done on eggs transfixed in a polymer to create contrast between the eggs and the background. This kills the eggs. The main advantage of the presented method is that it is non-invasive and only requires a minimum of handling of the eggs. As case studies we collected images of Atlantic haddock (Melanogrammus aeglefinus) and Atlantic cod (Gadus morhua) eggs. The eggs in the images were manually counted for verification of the methodology. The average counting error of false positives was 6% and the average counting error of false negatives was 2%. This demonstrates that the method is objective and accurate.     

铬对鲤、草鱼胚胎发育及鱼苗的毒性影响

以水体不同浓度铬（CrCl3.6H2O)处理草鲤鱼卵和鱼苗,观察铬对鱼卵的发育和鱼苗的毒性作用,结果表明：铬处理组浓度高于（2mg/L)对鱼苗,鱼胚发育有毒性作用;染毒7天内,10mgCr/L组鱼苗致死率30％,草,鲤鱼卵孵化率分别下降46％和88．9％,15mgCr/L组草鱼苗致死率达100％,鱼卵孵化率为零,两种鱼对铬的耐受量无明显差异。