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<正>一、盐城地区异育银鲫养殖现状及发病情况1.异育银鲫养殖现状江苏是鲫鱼的主产地,养殖面积在80万亩以上,2016年鲫鱼产量63.93万吨,位居全国之首。"全国鲫鱼看江苏,江苏鲫鱼看盐城",盐城因地域养殖环境好,适合鲫鱼的养殖,产量大、规格大,因此,鲫鱼也成了盐城的一张名片。盐城的鲫鱼养殖主要集中在大丰、东台、盐都、建湖、射阳、滨海、响水等地,其他主养区域分布在江都、高邮、宝应、武进、兴化等地。盐城地区鲫鱼养殖模式大致可以分为苗种养殖、成鱼精养和混养三类。鲫鱼苗种养殖主要集中在盐都,水花通常4月中下旬入塘,密度1万~ 相似文献
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鲫鱼价格上涨状况犹如昙花一现,江苏盐城地区8两以上规格的鲫鱼目前时价8.5元/斤,达到这种规格的成鱼寥寥无几;6-7两规格鲫鱼时价6.5-6.7元/斤,5月鲫鱼行情乍暖还寒,更让人堪忧的是“鳃出血”疾病如期而至。鲫鱼苗种价格10尾/斤规格为6元/斤,苗种养殖量偏小, ;区域内养殖结构在连续几年的瘟疫肆虐下基本调整为草鲫混养模式。预计6月份鲫鱼成鱼价格将会迎来小幅下降趋势,原因分析:“鳃出血”对鲫鱼养殖而言已成毁灭性的打击,近期该病的抬头势必让养殖户无奈选择低价抛售,鱼贩从控制风险的角度也将趁机压价。建议鲫鱼养殖户做好水质调节、保健预防,大规格的鲫鱼可根据养殖安全程度待价而沽。 相似文献
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@@@@“全国鲫鱼看江苏、江苏鲫鱼看盐城”,一语道出江苏鲫鱼养殖在全国首屈一指,其中,又以盐城为傲。近年来,受困于病害频发、种质退化等问题,江苏鲫鱼产业链正在发生变化。 相似文献
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江苏盐城是国内鲫鱼养殖最为集中的区域之一。随着鲫鱼密度的增加、水质的恶化,鲫鱼的疾病也呈现出多样化、复杂化的趋势。而鲫鱼的大红鳃是继暴发性出血病、孢子虫后鲫鱼的又一新病。从近几年发病情况来看,有愈演愈烈的趋势,由于盐城区域内养殖情况复杂,该病在防治方面遇到了困难,出现了反复用药难断根和治疗易反弹的情况,下面笔者就这种疾病进行一些粗浅的探讨。 相似文献
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<正>受"厄尔尼诺"现象影响,2019年盐城地区的气候较为异常,到7月中旬,水温仍在28℃左右,长时间处于鳃出血高发的水温区间(20~28℃),这就导致了上半年盐城主养区域鲫鱼鳃出血发病情况较往年更为严重。从4月初开始到7月下旬为止,各主养区域先后暴发鳃出血,发病程度也各不相同。有的地区因对鳃出血的发病规律 相似文献
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鲫鱼是江苏水产养殖量最大的品种,射阳、大丰等沿海滩涂地区为其主养区。2009年鲫鱼鳃出血病未出现之前,这一地区的养殖品种只有鲫鱼,但近两年,随着病害问题越来越严重,损失越来越大,养殖户不得不走上转型之路,在该地拥有8300多亩水面的养户李旭便是其中之一。 相似文献
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The variation of virulence of Renibacterium salmoninarum , the causative agent of bacterial kidney disease (BKD) in salmonid fish, was studied by infecting rainbow trout, Oncorhynchus mykiss (Walbaum), with two isolates (strains 325 and 932) from diseased Atlantic salmon, Salmo salar L., and one isolate (strain 4366) from an apparently healthy Atlantic salmon. Coho salmon, Oncorhynchus kisutch (Walbaum), were injected with the strain 932 to estimate difference in fish species resistance. Fish were removed by random sampling for other study purposes, a study design possible with analysis of lifetime distributions incorporating both sampling-, death- and survival-times. At the end of the experiment, the rainbow trout infected with strains 325, 932 and 4366 had a survival probability of 33%, 51% and 72%, respectively. The coho salmon infected with strain 932 had a 26% survival probability. The strain differences were significant according to the log-rank test, and the risk ratio between the strains ranged from 1·8 to 5·4. The strain from the apparently healthy fish was least virulent. The survival of the fish species was different over time. Rainbow trout were more likely to die early in the time course, but high numbers of coho died later, resulting in an overall risk of mortality of 1·4 in favour of rainbow trout. Differences in virulence may reflect changed selective pressure on R. salmoninarum when introduced from feral stocks into the environment of fish farms. 相似文献
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水硬度对七彩神仙鱼幼鱼发育的影响 总被引:4,自引:0,他引:4
采用不同硬度的水对七彩神仙鱼幼鱼进行饲养。6周龄幼鱼在硬度为7.94°dH±0.30°dH时饲养84d后,比在硬度为14.71°dH±0.23°dH水中的幼鱼个体大,生长速度快。表明较高硬度的水有利于七彩神仙鱼幼鱼的生长发育。 相似文献
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《水生生物资源》2003,16(5):461-465
Anti-proteinase activity was demonstrated in the seminal plasma of cyprinid fish species (bream, chub, ide, dace, asp, goldfish, roach, common carp) using electrophoretic techniques combined with a detection method based on inhibition of bovine trypsin. We found species-specific protease inhibitors in the seminal plasma of cyprinids. At least three bands of protease inhibitors with different migration rates could be identified by native PAGE. Higher variability was characterized for bands with slower migration rates. Visualization of inhibitors after SDS-PAGE under non-reducing conditions allowed estimation of their molecular weights. Apparent molecular weights were within the range of 51–59 and 47–54 kDa for the bands with slower and moderate migration rates, respectively. The molecular weight of fast migration bands for roach and common carp were estimated to 23 and 30 kDa, respectively. Inhibitors of common carp seminal plasma differed in their affinity toward serine proteases. Three inhibitors in common carp seminal plasma could be visualized using cod and bovine trypsin, but only two inhibitors (of high molecular weight) were recognized with chymotrypsin. There were differences in anti-proteinase activity and seminal plasma protein concentration in relation to the origin of common carp seminal plasma (breeding lines) and time of milt collection (spawning vs. post-spawning season). 相似文献
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牙鲆刺激隐核虫病的防治 总被引:1,自引:0,他引:1
2005年七、八月份,乐亭、滦南一带多家工厂化牙鲆养殖场发生刺激隐核虫病,此种病虫害发病急、传染快、死亡率高。发生过该病的养殖场牙鲆死亡率一般都在50%~80%之间,这种病害给牙鲆养殖业带来很大损失。 相似文献
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该研究通过肉眼观察、镜检,进行干露、饥饿、盐度突降、福尔马林等抗性试验,并采用病毒检测等方法,以期建立评估斑节对虾(Penaeus monodon)虾苗活力和质量标准。结果表明,斑节对虾健康虾苗具有趋光性、集群性,体表光洁,肌肉透亮,肠胃食物充盈等特性。测试虾苗干露时间以15min为宜,健康虾苗干露后能立即恢复活力,而病弱虾苗多出现死亡、昏迷现象;虾苗的成活率随饥饿时间的延长而降低,随福尔马林浓度升高和时间延长而降低,随盐度突降幅度增加而降低。健康虾苗能忍受100~200μL·L^-1福尔马林溶液30min,成活率近100%;在盐度20~30下虾苗的成活情况较好,而其在淡水中仅能存活1h。对虾苗进行病毒检测,可以避免养殖中因虾苗携带病毒而可能导致的病毒性疾病的暴发。 相似文献
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鳟鱼发眼卵和旨种运输是养鳟生产的重要环节。发眼卵多在冬季和早春运输,苗种多在晚春和夏季运输。苗种运输大多以鱼篓充氧进行短距离汽车运输,长途运输冷水性鱼苗种的实例很少。本文总结了金鳟和虹鳟苗种长途运输方法,以期与养鳟业界共同交流提高。一、包装材料和方法内包装材料是苗种运输专用塑料袋,规格54×104cm,外包装是泡沫塑料箱,规格63.5×45.5×30.5cm,纸箱规格64×46×32.5cm。塑料袋采取双层式,内装苗种和水共12.5kg,其中苗种0.5-1.3kg,100-2000尾。起运前苗种停食1-2天。运鱼用水水温调至6℃,鱼、水入袋后袋内… 相似文献
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该研究选取具有多态性的6对微卫星引物对构建的2批合浦珠母贝(Pinctada fucata)完全双列杂交家系的遗传多样性进行了分析。6个微卫星标记在9个家系360个个体中共检测到32个等位基因,有效等位基因(Ne)为1.758 7~3.586 5,观测杂合度(Ho)为0.144 4~0.488 9,期望杂合度(He)为0.432 0~0.722 2,Shannon指数(I)为0.691 9~1.507 4。9个家系都有单态位点,平均Ho为0.129 2~0.466 7,平均He为0.155 0~0.439 6,平均I为0.248 5~0.712 2。有19个位点(占35.19%)极显著地偏离Hardy-Weinberg平衡。各家系之间的遗传距离为0.109 0~1.137 2,遗传相似性系数为0.320 7~0.896 8。家系L4B46与L4B48的遗传距离最大,与D3D313的遗传距离最小。UPGMA法聚类分析显示,9个家系分为3支,L4B48单独成一支,B4D426、B4D427与D4B445聚成一支,其余家系聚成一支。该研究结果为合浦珠母贝家系选择育种的亲本选择与交配设计提供了科学依据。 相似文献
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猪的胎盘属于弥散型胎盘,这种胎盘的结构特点和饲养管理的不当,常常导致母猪胎衣不下发生,给生猪的生产繁殖带来极大损失。本文针对母猪胎衣不下发生病因、综合防治进行详细阐述,旨在对预防和治疗胎衣不下能有所帮助。 相似文献