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81.
我国蓝色粮仓科技创新的发展思路与实施途径 总被引:4,自引:0,他引:4
蓝色粮仓建设对保障食物安全、推动经济发展、催生新兴产业、彰显国家权益、改善生态环境以及突破产业瓶颈具有重要意义。在当前科技和产业背景下,如何卓有成效地构建蓝色粮仓已成为社会各界关注的热点。本文明确了蓝色粮仓的概念和特点,分析了蓝色粮仓构建的必要性和可行性,提出了实现渔业产业由大国向强国跨越以及提升科技创新和产业发展能力的总体目标,从聚焦重大需求、构建科技创新链,坚持原创驱动、突破重大科学问题,强化集成示范、支撑产业健康持续发展等方面论述了实施途径,即按照基础研究、重大共性关键技术、典型应用示范全链条布局的要求,坚持生态优先谋划,陆海统筹布局,针对种质创制、健康养殖、资源养护、友好捕捞、流通加工五大产业类型需求,实施良种引领、空间拓展、技术升级、产业示范四大行动,建立智慧养殖、智能捕捞、绿色加工三大体系,满足优质蛋白供给和产业转型升级两大需求,最终构建中国特色的蓝色粮仓。 相似文献
82.
83.
Dalila F. Canizales-Rodríguez Víctor M. Ocaño-Higuera Enrique Marquez-Rios Abril Z. Graciano-Verdugo Jose L. Cárdenas-López María S. Yepiz-Gómez 《Journal Of Aquatic Food Product Technology》2013,22(3):259-269
Postmortem changes in blue shrimp (Litopenaeus stylirostris) muscle were studied on the basis of biochemical, chemical, physical, and microbiological changes during an 18 day storage period at 0°C. Adenosine 5′-triphosphate (ATP) content, breakdown products, K-value, pH, trimethylamine nitrogen (TMA-N), total volatile basic nitrogen (TVB-N), water holding capacity (WHC), color, and texture (shear force) changes were examined. Also, total mesophilic and psychrophilic bacterial counts were measured. K-value increased linearly (r2 = 0.98) from an initial value of 1.37 ± 0.59 to 59.42 ± 6.05% at Day 18. Spoilage indicators TVB-N and TMA-N increased from 29.56 ± 1.33 and 0.69 ± 0.25 to 39.04 and 2.04 ± 0.59 mg of N/100 g at Day 18, respectively; meanwhile, the total viable counts of mesophilic and psychrophilic bacteria increased from 3.48 ± 0.44 and 2.61 ± 0.29 log CFU/g to 6.27 ± 0.21 and 7.14 ± 0.39 log CFU/g, respectively, which indicated spoilage at the end of the storage period. The pH, texture, WHC, and color were affected (p < 0.05) during the storage period. Overall, results indicate that blue shrimp muscle quality was maintained for 12 days of storage in ice. 相似文献
84.
原油和燃油对南海重要海水增养殖生物的急性毒性试验 总被引:14,自引:0,他引:14
测定了南海原油、0号柴油和20号柴油对3种仔虾、种仔鱼和4种贝类的急性毒性。油类对仔鱼和仔虾的毒性大小顺序为:0号柴油〉20号柴油〉南海原油;对3种贝类(文蛤除外)的毒性大小顺序为0号柴油〉南海原油。油类分散液的毒性大于其水溶性组分。在曝油的3种仔虾中,刀额新对虾对0号柴油和20号柴油的耐受力最弱,而日本对虾对南海原油最为敏感。曝油仔鱼对3种湍类的耐受力顺序为:黄鳍鲷〉前鳞鲻〉黑鲷,而七星鲈对0号 相似文献
85.
Wilson Wasielesky Jr Paulo César Abreu Luis Henrique Poersch Fabiano Thompson Eduardo Luis Cupertino Ballester 《Aquaculture Research》2012,43(5):706-712
A reduction in light intensity may increase shrimp activity, although it may also negatively affect the development of photoautotrophic organisms present in biofilm, an important natural food source for shrimp. This experiment evaluated the influence of light intensity on biofilm development and on the growth of cultured Farfantepenaeus paulensis juveniles. Six cages were deployed in a shrimp culture pond and stocked with 60 juveniles (0.72 ± 0.03 g). Three cages were randomly chosen and covered with five layers of polyamide net to reduce light incidence (shaded treatment), while the other three cages were not covered (control treatment). Biofilm chlorophyll a and microorganism abundance, as well as shrimp growth, were monitored during the experiment. Chlorophyll a concentration and the abundance of bacteria and flagellates were significantly lower in the shaded treatment (P<0.05). After 75 rearing days, shrimp stocked in control treatment achieved significantly higher (5.98 g) (P<0.05) mean weight than shrimp reared in shaded treatment cages (5.13 g). Similarly, the biomass produced was also significantly higher (P<0.05) in the control treatment (322.92 g) than in the shaded treatment (287.31 g). The results of this study demonstrate that light intensity has a huge influence on shrimp performance mainly due to the increase in natural food availability. 相似文献
86.
Utilization of corn gluten meal as a protein source in the diet of white shrimp Litopenaeus vannamei
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A 57‐day feeding trial was designed to assess the potential of corn gluten meal (CGM) as a plant protein source in practical feeds for white shrimp Litopenaeus vannamei. Five experimental diets providing 350 g kg?1 protein and 110 g kg?1 lipid were prepared, where 0%, 25%, 50%, 75% and 100% of fishmeal (FM) protein was substituted by protein from CGM. The results showed that partial or complete replacement of FM with CGM did not affect survival. The growth of the shrimp declined as the levels of CGM increased, diets containing CGM showing a significantly lower final weight (3.2–5.9 g) and specific growth rates (1.7–2.7% per day) compared to those fed on the diet with 0 CGM (7.1 g and 3.0% per day). Feed conversion ratio was also significantly affected by CGM level. The inclusion of CGM resulted in a statistical decrease in the apparent digestibility (AD) of dry matter from 77.9% to 66.0% and in AD of protein from 80.5% to 52.0%, of feed. The AD of amino acids, with the exception of lysine, declined with the dietary incorporation of CGM. In summary, reduced palatability, low protein digestibility and a deficiency of lysine and methionine seem to be the major reasons behind a depressed growth in shrimp fed on CGM protein‐based diets. 相似文献
87.
环境胁迫对对虾免疫系统的影响研究 总被引:2,自引:0,他引:2
环境胁迫(environmental stress)是指环境对生物所处的生存状态产生的压力,分为急性环境胁迫和慢性环境胁迫。捕捞、干扰、水质的突变等可以引起急性环境胁迫,而水质逐渐恶化和高密度放养等会造成慢性胁迫。近年来随着人类活动范围的不断扩大和程度的加深,环境资源受到了很大的破坏,养殖对虾受到的环境胁迫日益严重。这些胁迫可使对虾产生应激反应,虽然这是一种保护性反应,但持续处于应激状态,机体的免疫防御体系的功能会受到抑制,就会影响到其抗病力。当前对虾的病害越来越严重,大规模的死亡已经成为制约养殖业发展的瓶颈。 相似文献
88.
《Communications in Soil Science and Plant Analysis》2012,43(1):79-86
Abstract The bismuth sulfide and methylene blue colorimetric finishes for soil sulfate determination by the Johnson‐Nishita distillation method were examined and compared. Both procedures gave comparable results when applied to soils and soil extracts, but the bismuth method was more rapid and more reliable. Nitrogen flow rate over the range 100–500 ml/min was not critical for the bismuth method, provided appropriate distillation times were employed. However, the release and transfer of hydrogen sulfide in the bismuth method was effected in one‐third of the time required for the méthylène blue finish, largely due to the elimination of a gas‐washing step. Predrying of soil extract samples increased recovery of hydrogen sulfide with the bismuth procedure arid could be used to increase sensitivity. Nitrate interference was observed with the bismuth procedure but attributed to interference during the reduction step. The bismuth procedure can readily be adapted for microdetermination in the 0–40 ppm sulfate‐S range. 相似文献
89.
《Journal Of Applied Aquaculture》2013,25(1-2):101-108
Outbreaks of anemia (CCA) in channel catfish, Ictalurirs punctatus, in Mississippi occur predominantly during spring and fall. Between October, 1990 and May, 1991, twenty-seven cases of CCA were submitted to the Mississippi Cooperative Extension Service-College of Veterinary Medicine Fish Diagnostic Laboratories. Histologic lesions were identified in the head and trunk kidneys of all affected fish. The head kidney contained less than 25% immature hematopoietic tissue in 3 of 22 cases (14%). 25-50% immature hematopoietic tissue in 7 of 22 cases (32%), and greater than 50% immature hematopoietic tissue in 12 of 22 cases (54%). The trunk kidney contained less than 25% immature hematopoietic tissue in 5 of 27 cases (18%), 25-50% immature hematopoietic tissue in 15 of 27 cases (56%), and greater than 50% immature hematopoietic tissue in 7 of 27 cases (26%). The histopathologic findings noted in cases of CCA from Mississippi affect primarily the hematopietic tissues of the head and trunk kidneys. 相似文献
90.
Carla Nunes Josep Usall Neus Teixidó Miguel Miró Immaculada Viñas 《European journal of plant pathology / European Foundation for Plant Pathology》2001,107(5):543-551
Pome fruits are poor in nitrogenous compounds and the addition of nitrogen can improve colonisation of the fruits by antagonists. Twenty-two nitrogenous compounds were evaluated for their effect on Candida sake (CPA-1) growth in vitro. Ten compounds that induced greater growth were applied with the antagonist to wounded fruits to evaluate their effect on enhancing control of Penicillium expansum. Calcium chloride and 2-deoxy-D-glucose were also tested. L-serine and L-aspartic acid enhanced biocontrol by C. sake against P. expansum on apples. On apples and pears, ammonium molybdate, calcium chloride and 2-deoxy-D-glucose improved the capacity of the antagonist to control P. expansum. The addition of ammonium molybdate at 1 mM allowed C. sake to be used on apples and pears at a lower concentration without diminishing control. Similar results were observed with the addition of calcium chloride to the antagonist. 2-deoxy-D-glucose at 6 and 18 mM enhanced biocontrol on pears by over 81%, but on apples the improvement of biocontrol was observed only at 6 mM. In cold storage, the combination of ammonium molybdate and C. sake completely eliminated the incidence of blue mould on pears, and reduced its severity and incidence by more than 80% on apples. 相似文献