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1.
The zebrafish is an established vertebrate-animal model in biomedical research. Currently, their mass culture is mainly done using systems provided by commercial suppliers. Commercial systems are compact, recirculating, and use auto-cleaning tanks. These features minimize space use, labour cost, and water wastage; thus, facilitating maintenance of a large number of zebrafish using minimal resources. However, the often considered costs associated with these systems often impose a barrier to current and prospective researchers, especially those with limited funds or working in labs with no access to institutional centralized zebrafish culture facilities. In contrast to commercial systems, custom-made zebrafish maintenance systems are also described in the literature. To distinguish custom-made system from commercial systems, we termed them as “open-design” systems. Open-design systems are cost-effective, modular, and frequently being improved by zebrafish researchers. However, for further development and to present them as a viable option for zebrafish researchers around the world, a review of their current status and technical understanding is required. Here, we compile the disparate data on the purpose and technological development of the open-design systems. We believe this review will be a valuable resource for all zebrafish users and help streamline the open-design technology for zebrafish culture. 相似文献
2.
A jet fish pump with a throat of ø60 mm was designed to study its performance in the transport of different fish species and the physiological changes in fish thereafter. Experiments were conducted to investigate the fish transport rate and energy required to transport each ton of fish when transporting Carassius auratus, commonly known as the Chinese goldfish, Megalobrama amblycephala, or Wuchang bream, and Ctenopharyngodon idella, the grass carp. Fish were examined for external injuries as well as for several important enzymes and hormones which are indicators of tissue injury and stress. The results showed that the transport rate for all three species of fish rose dramatically with an increase in the primary stream rate. In this experiment, the transport rates of C. auratus, M. amblycephala and C. idella reached 2357 ± 37.2 kg ∙ h−1, 2888 ± 41.6 kg ∙ h−1, and 2060 ± 40.2 kg ∙ h−1, respectively. However, both injury rate and energy required to transport each ton of fish increased no matter whether the primary stream rate was too low or too high. Considering both transport rate and injury rate, the mean primary stream rate of 80 m3 ∙ h−1 was determined to be the optimal operating condition in this experiment. Fish were stressed and most likely some of their organs were damaged. However, most physiological indexes almost fully recovered after several hours. 相似文献
3.
应用高蛋白料精等量替代鱼粉饲喂肥育猪 ,其结果在 42d试验期内高蛋白料精组头均增重 19.0 6kg ,比鱼粉组多增重 2 .12kg ,增重率提高 12 .5 2 %,头均多增收益 2 1.2 1元 ,差异显著 (P <0 .0 5 )。 相似文献
4.
This work proposes a computer vision procedure for counting Twospot astyanax (Astyanax bimaculatus) oocytes in Petri dishes using images captured by smartphone. First, the proposed procedure uses simple linear iterative clustering (SLIC) to divide the images into groups of pixels (superpixels). Then, based on their color and space characteristics, the images are classified into light background, dark background, dirt, or oocyte by a machine learning algorithm. Five different types of machine learning algorithms were tested: support vector machines (SVM), decision trees using the algorithm J48 and random forest, k-nearest neighbors (k-NN), and Naive Bayes. To train the algorithms, 8.578 superpixels were classified by an expert into oocyte (n = 354), dirtiness (n = 651), dark background (n = 3.622), and light background (n = 3.951). Of the five learning algorithms, SVM obtained the best result with 97% correct oocyte recognition. Given the wide availability of smartphones, we therefore conclude that the presented procedure can be a valuable tool in future experiments and studies on fertilization and hatching success in Twospot astyanax. 相似文献
5.
This work proposes a method for the statistical monitoring of the weekly weight of shrimp in a fish farm. The design of control charts for shrimp growth presents several challenges, the main ones being the presence of trend and autocorrelation. Several control charts are proposed, the most efficient being a chart based on the residuals of a second order autoregression whose parameters vary with the week. A control chart with less computational complexity is also provided. It is simply based on growth rates and works well at detecting negative weight changes. Real data from a large shrimp farm has been used for both the design and the evaluation. 相似文献
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针对逻辑建模在数据仓库构建过程中的重要性,介绍了数据仓库创建的基本步骤,并利用实例深入而详细地研究了逻辑模型的设计,分析了几种逻辑模型的特点及其使用场合。 相似文献
9.
水丰水库的渔获量1961-1980年间变化于47-300t,1981-1984年增长到740-1321t,1985-2000年为2270-4926t。渔获物组成中以亚洲公鱼为主,1980-2000年亚洲蚣鱼占总渔获的29.6%-93.0%,平均为65.6%。鲁鲫鱼占6.2%-16.4%,鲢鳙鱼占8.1%-13.3%,鳊鲂占1.8%-11.3%,虾占5.9%-16.1%,其它鱼类占2.4%-9.3%。2000年大银鱼占总渔获的2.8%。1985-2000年水库鱼类资源相对稳定。亚洲公鱼、青虾和大银鱼三种小型经济鱼虾的种间关系表现为互利共生,竞争和残敌关系,可能向种间形成平衡调节方向发展。 相似文献
10.
Qinghui Ai Kangsen Mai Beiping Tan Wei Xu Qingyuan Duan Hongming Ma Lu Zhang 《Aquaculture (Amsterdam, Netherlands)》2006,260(1-4):255-263
A growth experiment was conducted to investigate the effects of replacement of fish meal (FM) by meat and bone meal (MBM) in diets on the growth and body composition of large yellow croaker (Pseudosciaena crocea). Six isonitrogenous (43% crude protein) and isoenergetic (20 kJ g− 1) diets replacing 0, 15, 30, 45, 60 and 75% FM protein by MBM protein were formulated. Each diet was randomly allocated to triplicate groups of fish in sea floating cages (1.0 × 1.0 × 1.5 m), and each cage was stocked with 180 fish (initial average weight of 1.88 ± 0.02 g). Fish were fed twice daily (05:00 and 17:30) to apparent satiation for 8 weeks. The water temperature ranged from 26.5 to 32.5 °C, salinity from 32 to 36‰, and dissolved oxygen content was approximately 7 mg l− 1 during the experimental period. Survival decreased with increasing dietary MBM and the survival in the fish fed the diet with 75% protein from MBM was significantly lower than other groups (P < 0.05). There were no significant differences in specific growth rate (SGR) among the fish fed the diets with 0 (the control group), 15, 30 and 45% protein from MBM. However, SGR in the fish fed the diets with 60 and 75% protein from MBM were significantly lower than other groups (P < 0.05). No significant differences in feeding rate were observed among dietary treatments. The digestibility experiment showed that the apparent digestibility coefficients (ADC) of dry matter, protein, lipid and energy of MBM were significantly lower compared with those of FM (P < 0.05). Essential amino acid index was found to be correlated positively with SGR in the present study, suggesting that essential amino acid balance was important. Body composition analysis showed that the carcass protein and essential amino acids were not significantly affected by dietary MBM. The lipid and n-3 highly unsaturated fatty acid (n-3 HUFA) in fish muscle, however, significantly decreased with increasing dietary MBM. These results showed that 45% of FM protein could be replaced by MBM protein in diets of large yellow croaker without significantly reducing growth. It was suggested that the reduced growth with higher MBM was due to lower digestibility and imbalance of essential amino acids. 相似文献