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981.
982.
基于无线射频识别(RFID)技术建立亲鱼养殖管理系统能够大大减少人工工作量,并对亲鱼养殖全程实现可靠精细化的管理、跟踪和追溯。测试分析结果表明,天线直径分别为25 cm和40 cm两种规格的RFID抄网读写器,能够在平均距离16.41~22.82 cm范围内,稳定地读写亲鱼皮下肌肉内的玻璃标签,在后台软件系统的支持下,能够实现对亲鱼养殖全程的有效管理、跟踪和追溯。 相似文献
983.
We examined the effects of a yeast‐derived protein source (NuPro®) as a replacement for menhaden fish meal on weight gain, specific growth rate (SGR), food conversion ratio (FCR), whole‐body composition and disease resistance in juvenile channel catfish (9.9 ± 0.2 g fish?1). NuPro® replaced fish meal at six levels (0, 25, 50, 75, 100 and 125 g kg?1 diet). Catfish were sampled for whole‐body composition and then challenged with the bacterium Edwardsiella ictaluri. Growth performance was negatively affected (P < 0.01) when NuPro® was added at 125 g kg?1 diet. The amount of whole‐body fat decreased (P < 0.05) when NuPro® was added at 75 g kg?1 or more of the diet. Regardless of the amount of NuPro® added, survival after challenge with E. ictaluri was similar among treatments. Results indicate that up to 100 g kg?1 of NuPro® can be added without negatively affecting growth performance. The yeast‐derived protein source used in this study is a sustainable protein alternative that could be used as a partial replacement for fish meal in juvenile channel catfish diets. 相似文献
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985.
986.
OLIVER BERRY PHILLIP ENGLAND DAVID FAIRCLOUGH GARY JACKSON JIM GREENWOOD 《Fisheries Oceanography》2012,21(4):243-254
Determining the extent of dispersal in exploited marine fishes is essential for understanding their population dynamics and optimising management. The West Australian dhufish, Glaucosoma hebraicum, is a highly sought‐after, large and long‐lived reef‐dwelling species, endemic to south‐western Australia. Stock assessments indicate that this indicator species is overexploited. The fishery is managed using a zone‐based system, which implicitly assumes a high degree of demographic independence among zones. While tagging studies indicate limited movement of adult G. hebraicum, there is no understanding of the spatial scale of dispersal of its larvae and thus the true extent of interdependence of management zones. We analysed 13 microsatellite DNA loci to characterise the extent of gene flow, and conducted particle tracking simulations to model larval transport in this species. Genetic data demonstrated that some local recruitment was likely, but that on a broad scale gene flow between the management zones was extensive, and the entire fishery represents a single genetic stock. Hydrodynamic modelling predicted that the majority of dhufish larvae recruit from within the management zone where they are spawned, and that inter‐annual variation in current velocities has limited effect on the extent of larval transport. Because management zones are likely to be largely independent in terms of both larval and adult recruitment, heavy localised fishing pressure has the potential to reduce the abundance and reproductive capacity of this species in highly fished areas, but it should have limited impact on neutral genetic diversity. 相似文献
987.
988.
G.F. Dong F. Huang X.M. Zhu L. Zhang M.X. Mei Q.W. Hu H.Y. Liu 《Aquaculture Nutrition》2012,18(6):673-684
An 86‐day growth trial was conducted to investigate the effect of dietary oxidized fish oil on the growth and cytopathology of juvenile channel catfish (Ictalurus punctatus). Four diets containing 0 g kg?1 (control: fresh fish oil), 30 g kg?1 (low‐oxidized oil group), 60 g kg?1 (medium‐oxidized oil group) and 90 g kg?1 (high‐oxidized oil group) graded oxidized oil levels with the same dietary lipid level (90 g kg?1 diet) were evaluated. The results show that the specific growth rate decreased with increasing dietary oxidized oil level (P < 0.05). All examined liver and kidney tissues in all dose groups exhibited what appeared as dose‐dependent cellular modifications. In addition, lipid droplet accumulation in the hepatocytes of fish in all dose groups was increased, and their localizations were distinctly different between all dose groups. The ultrastructural changes suggest the progression of mitochondrial vacuolation, especially in the renal tubules, in all dose groups. These results reveal a previously underappreciated effect of dietary oxidized fish oil on channel catfish kidneys. Overall, a series of nutriphysiological responses were adversely affected by exposure to dietary oxidized fish oil, and the corresponding interference patterns on the metabolism and transport of nutrients within cells were observed. 相似文献
989.
Foteini Kokou Pavlos Makridis Maroudio Kentouri Pascal Divanach 《Aquaculture Research》2012,43(10):1520-1527
Five cultures of microalgae (Chlorella minutissima, Tetraselmis chui, Nannochloropsis sp., Arthrospira platensis and Isochrysis sp.) with no culturable bacteria were tested for their ability to inhibit the growth of six Vibrio bacterial strains (V. parahaemolyticus, V. anguillarum, V. splendidus, V. scophthalmi, V. alginolyticus and V. lentus). The influence of light on the antibacterial activity of the microalgae was investigated. All microalgae cultures inhibited the growth of bacteria compared with the control treatments (P < 0.05), and their antibacterial activity was not influenced by the presence or absence of light. In the control groups, the numbers of bacteria increased exponentially during the experimental period in the absence of microalgae cells demonstrating that the bacterial cells were able to utilize the growth medium of microalgae cultures. The present results may explain the low levels or absence of Vibrio strains in microalgae cultures, and the positive effect of addition of microalgae in rearing of fish larvae, and implicate the production of antibacterial compounds by microalgae cells. 相似文献
990.
The effect of partial substitution of dietary fish meal with a high‐value soybean meal (HVS) and a commercial soybean meal (CSM) on the growth performance in juvenile Japanese seabass (8.3±0.2 g body weight) was determined. Nine isonitrogenous (crude protein 44%) and isoenergetic (20 kJ g?1) practical diets replacing 0 (the control), 15%, 30%, 45% and 60% fish meal protein by soybean meal protein (HVS or CSM) were formulated. Each diet was randomly assigned to four replicate cages (1.5 × 1.5 × 2.0 m). Fish were fed twice daily for 10 weeks. Growth was significantly reduced with increased soybean inclusion in fish fed both the soybean sources. Independent of the soybean source used, increased inclusion of soybean meal decreased the growth performance. When the substitution level was 45% or more in CSM and 60% in HVS, the specific growth rate (SGR) and the feed efficiency ratio (FER) were significantly lower compared with the control. These results indicated that CSM protein could substitute for 30% fish meal protein, while the substitution level of HVS protein could be 45%, which did not influence the growth of juvenile Japanese seabass. The higher substitution level for HVS compared with CSM was probably due to better nutritional values. 相似文献