镜泊湖蒙古鲌人工繁育技术初步研究

从镜泊湖采捕野生蒙古鲌(Culter mongolicus mongolicus)32尾进行了人工繁殖试验。结果显示,注射人工合成激素可促使成熟亲鱼自然发情产卵,水温22~25℃时,催产药物的效应时间为10 h,有5尾雌鱼产卵,共获得受精卵1.5×105粒,孵出鱼苗1.25×105尾,其受精率、孵化率和畸形率为83.6%、90.3%和6.7%。镜泊湖蒙古鲌是产黏性卵的鱼类,吸水膨胀后卵径为(1.42±0.04)mm(n=30),水温23~24℃时,从卵授精到开始破膜出苗约38 h。镜泊湖蒙古鲌的鱼苗可采用土池发塘培育,饲养30 d体长达(3.24±0.29)cm,体重达(0.35±0.09)g,饲养100 d体长为(5.96±0.33)cm,体重为(2.28±0.32)g。     

太湖翘嘴红鲌胚胎发育及胚后发育观察

对从太湖收集的野生翘嘴红鲌(Erythroculter ilishaeformis Bleeker)经人工繁殖获得子一代,并在池塘养殖条件下对其进行人工培育获得成熟亲鱼.于2005年6月,经人工催产、人工授精获得受精卵,对其胚胎及胚后发育全过程进行了系统观察.结果表明,池塘养殖条件下人工培育能获得成熟亲鱼,经人工催产所获得的翘嘴红鲌受精卵为圆球型,呈墨绿色、青灰色、黄色等3种颜色;平均卵径为0.9 mm(O.72～1.18 mm),吸水后平均卵径为1.2mm.翘嘴红鲌胚胎发育过程可分为19期,在水温23～25℃范围内,受精30 min后开始第1次卵裂,受精后9 h 20min开始形成器官,受精后约26 h仔鱼开始出膜,刚出膜的仔鱼全长为4.10-4.67 mm,胚胎发育总积温为619.82℃·h.翘嘴红鲌胚后发育过程可分为仔鱼和稚鱼2个阶段共15个发育期,在26～31℃水温下历时670 h,其中仔鱼阶段从鱼苗孵出到腹鳍形成期,稚鱼阶段从鳞片出现到鳞片形成期.对各发育时期外部形态特征进行了详细的描述.     

秀丽高原鳅胚胎发育观察

2015年7月,在大理州鹤庆县黑龙潭采集性腺成熟的秀丽高原鳅个体200尾,在水温17.0℃条件下,以促黄体素释放激素类似物5μg/kg+人绒毛膜促性腺激素1000IU/kg的药剂背部肌肉一次注射(雌鱼0.2mL,雄鱼减半),获卵1517粒,效应时间约24h。秀丽高原鳅卵呈黏性,成熟卵粒卵径为1.03mm,发育至眼囊出现时达到1.33mm,在水温(17.5±1.0)℃条件下,观察受精卵的胚胎发育过程,经历卵胚盘形成阶段、卵裂阶段、囊胚阶段、原肠胚阶段、神经胚形成阶段、器官形成阶段和孵化出膜阶段共7个阶段,经约77.75h孵化,开始出膜,出膜后仔鱼全长3.66mm,卵黄经约120h吸收后,开始平游觅食。     

普安银鲫胚胎发育的初步研究

经人工催产、人工授精获得普安银鲫受精卵,对其胚胎发育过程和各发育时期外部形态特征进行了连续观察,并研究了不同温度条件下其胚胎发育的特点。研究结果表明,普安银鲫受精卵近似圆球形,淡灰色,沉性卵,强粘性;卵径1.50mm,吸水后1.88mm;受精后开始形成卵间隙,且植物极的卵间隙大于动物极的;卵间隙形成过程中卵黄收缩,略变小。普安银鲫胚胎发育过程可分为23个发育期,水温18℃时需98.72h出膜,水温24℃和26℃时分别需要56.48h、48.2h出膜。不同温度条件下,普安银鲫胚胎发育早期(胚盘～原肠胚)在18℃恒定水温条件下存活率最高,发育后期阶段(神经胚～出膜)在24℃恒定水温条件下存活率最高。     

新疆裸重唇鱼胚胎及早期仔鱼发育的形态观察

2016年4月1日—4月19日,在水温12～14℃下采用催产、人工授精和室内孵化方式获得暂养的野生新疆裸重唇鱼Gymnodiptychus dybowskii受精卵和仔鱼,观察其胚胎发育和早期仔鱼的形态特征。结果显示:新疆裸重唇鱼成熟鱼卵为亮黄色或橙色,卵径(2.2±0.28)mm,受精约35min后卵周隙达到最大,卵径2.90～3.40mm,卵黄约占卵体积的3/5。整个发育过程可分为受精卵、卵裂期、囊胚期、原肠胚期、神经胚期和器官形成期6个阶段。在水温(16±2)℃下,胚胎发育积温为2 359h·℃,187h仔鱼上浮。研究结果表明,新疆裸重唇鱼的胚胎发育特征与新疆地区其他几种裂腹鱼类存在一定差异。     

长丰鲢胚胎发育的初步观察

在(24±1)℃温度条件下观察长丰鲢(Changfeng silver carp)受精卵发育过程及其胚胎发育各个时期的形态特征。结果显示:长丰鲢受精卵为漂流性卵(半浮性卵),无油球,细胞质均匀分布,卵径为(1.55±0.05)mm,吸水后卵膜膨大,卵径达到(5.10±0.40)mm。在水温(24±1)℃的条件下,胚胎发育总历时为(28.5±1.0)h,胚胎发育过程所需总积温为(685.0±62.3)℃獉h。长丰鲢受精卵卵裂方式与其他家鱼一样,属于盘状卵裂,本文依据胚胎发育各阶段的形态特征,将其划分为7个连续发育的关键阶段,18个不同的时期,分别为受精卵期、卵裂期、囊胚期、原肠胚期、神经胚期、器官发生期和出膜期。     

斑鱾胚胎发育初步观察

通过对人工网箱养殖4年的斑鱾(Girella punctata Gray)亲鱼进行LHRH-A3激素催产,获得自然产卵的受精卵,于实验室中进行培育孵化,连续观察斑鱾胚胎发育的全过程。实验结果表明,斑鱾受精卵呈圆形,卵径0.882±0.041 mm、卵黄直径0.807±0.036 mm,具1个圆形油球,油球径为0.266±0.023 mm。在孵化水温23±0.5℃、盐度33.8条件下历时28 h 20 min完成整个胚胎发育过程,初孵仔鱼全长1.574±0.109mm。胚胎发育过程可划分为6个阶段,即受精卵、卵裂期、囊胚期、原肠胚期、神经胚期和器官形成期,包括27个发育时期。实验旨在了解斑鱾的胚胎发育规律,为开展斑鱾的人工繁殖提供基础资料。     

乌原鲤的胚胎发育特征

通过干法授精获得乌原鲤受精卵,对其胚胎发育全过程进行连续观察。结果显示,乌原鲤成熟卵子呈圆球形、亮黄色、具黏性,卵径1.68~1.98mm,吸水膨胀后卵径2.28~2.57mm。水温(20±1)℃时,受精卵至出膜时长为80.8h,积温1616.0℃·h。乌原鲤胚胎发育与其他鱼类胚胎发育过程相似,历经受精卵、卵裂、囊胚、原肠胚、神经胚、器官形成至出膜6阶段,各发育阶段所需积温分别为44.4、136.0、127.0、130.2、55.0、1123.4℃·h。出膜阶段历时47.45h,初孵仔鱼自尾部破膜孵出,全长约6.10mm,体高1.60mm。温度对乌原鲤胚胎发育及出膜阶段影响明显,水温(20±1)℃比水温(15±1)℃胚胎仔鱼出膜时间更早、出膜更同步、出膜时段更集中。     

唐鱼胚胎发育观察

唐鱼(Tanichthys albonubes)是一种小型鲤科鱼类,是华南地区的特有种。本研究报道对唐鱼胚胎发育过程的观察结果。唐鱼的受精卵近卵圆型,其卵径为(1.017±0.001)mm。根据其胚胎发育过程的形态特征,胚胎发育全程可划分为7个阶段:受精卵胚盘形成阶段、卵裂阶段、囊胚阶段、原肠胚阶段、神经胚形成阶段、器官形成阶段和孵化出膜阶段。观察结果表明,在不同的水温条件下发育历程不同:当水温分别在14.0-16.8℃、22.5-25.0℃和28-30℃条件下,受精卵分别经过147 h、50 h和28 h发育而孵出。文中讨论了唐鱼胚胎形态及胚细胞的分化特点,以及水温对胚胎发育的影响。     

云南光唇鱼的人工繁殖和胚胎发育观察

对人工繁育至性成熟的3龄云南光唇鱼进行人工催产,观察受精卵胚胎发育情况。结果显示:采用HCG、LHRH-A_2和DOM组合注射催产,在水温16.3~18.7℃条件下,效应时间37~38 h,平均催产率为80%。云南光唇鱼的受精卵为沉性卵,吸水膨胀后,平均卵径2.5 mm;受精卵经过胚盘形成期、细胞分裂期、囊胚期、原肠期、神经胚器、器官发育期和出膜期,历时103 h 30 min孵出仔鱼(水温16.0~18.3℃),初孵仔鱼全长6 mm。以原肠中期计算,受精率为75%,孵化率约53%。     

Esophagoscopy and gastroscopy in dogs and cats. Technics and indications

A report is presented of esophagoscopy and gastroscopy in cats and dogs using flexible endoscopes. Following consideration of the basic equipment, an account is given of patient preparation and anesthesia, topography, investigation technique and normal findings. Diagnostic potential, indications and risks involved are discussed.     

虾蟹血淋巴的抽取与固定

随着人们对甲壳动物生理生态学研究的逐步深入,尤其是与免疫应答密切联系的血液生理学领域被广泛关注.抽取和固定血淋巴,成为进行血液学研究必不可少的步骤.那么如何更好地抽取和固定血淋巴呢,本文以虾蟹为例做了总结,以供参考.     

中国鲟鱼的保护、管理与产业化

1　世界现存鲟鱼的种类和资源鲟鱼是一类起源早、具有重要科学研究价值和极高经济价值的稀有物种 ,多数种类个体大 ,半数种为溯河洄游产卵鱼类。按目前较为公认的分类系统 ,现存鲟鱼类有 2科 6属 2 7个种 ,隶属于硬骨鱼纲、软骨硬鳞总目、鲟形目 (Acipenseriformes) ,其中鲟属有 17个种 ,主要经济种类在其中。它们全部分布于北半球 ,现存 9个自然分布区为 :太平洋东岸、北美大湖地区、大西洋西北部、北美密西西比河流域和墨西哥湾、大西洋东北部、里海地区、西伯利亚及北冰洋流域、黑龙江和日本海、长江和珠江。鲟鱼自然种群资源稀少 ,在过…     

Achieving sustainable aquaculture: Historical and current perspectives and future needs and challenges

Important operational changes that have gradually been assimilated and new approaches that are developing as part of the movement toward sustainable intensive aquaculture production systems are presented via historical, current, and future perspectives. Improved environmental and economic sustainability based on increased efficiency of production continues to be realized. As a result, aquaculture continues to reduce its carbon footprint through reduced greenhouse gas emissions. Reduced use of freshwater and land resources per unit of production, improved feed management practices as well as increased knowledge of nutrient requirements, effective feed ingredients and additives, domestication of species, and new farming practices are now being applied or evaluated. Successful expansion into culture of marine species, both off and on shore, offers the potential of substantial increases in sustainable intensive aquaculture production combined with integrative efforts to increase efficiency will principally contribute to satisfying the increasing global demand for protein and food security needs.     

Food habits and growth of silver and bighead carp in cages and ponds

Analysis of intestinal contents of silver carp (Hypophthalmichthys molitrix) and bighead carp (Aristichthys nobilis) showed that silver carp consumed primarily phytoplankton while bighead carp consumed large quantities of zooplankton and detritus in addition to phytoplankton. The size of particles filtered by the bighead carp was larger (17–3,000 μm) than that filtered by silver carp (8–100 μm). Artificial feed was readily consumed by bighead carp but not by silver carp. No growth difference was indicated for silver carp in fertilized ponds and ponds receiving artificial feed. Growth of bighead carp increased substantially with the addition of artificial feed. Silver carp grew more rapidly in cages than bighead carp.     

虾蟹专用肥的研究开发及应用

20 0 1年 ,江苏省高邮市农林局与中国水产科学研究院淡水渔业研究中心及扬州市春申生物化工有限公司共同承担了江苏省水产更新工程项目———“虾、蟹专用肥料的开发研究与推广”。经项目组人员的共同努力 ,现已顺利完成项目任务 ,研究开发的虾、蟹专用肥在试用和大面积推广应用中取得了显著效果。虾、蟹专用肥已被列为江苏省第一批无公害水产品基地拟用鱼药、饲料推荐产品 ;也是江苏省水产技术推广站、安徽省水产技术推广站、江苏省高邮市农林局、江苏省兴化市水产局、江苏省宝应县水产局、安徽寿县水产局等十多个水产行政主管和技术推广部…     

Fish assemblage associations and thresholds with existing and projected oil and gas development

Energy development threatens fish and wildlife resources worldwide. This study used constrained ordinations to show fish assemblage structure associated with oil and gas well densities in the Colorado River Basin, Wyoming, but well densities explained only 6.4% of assemblage structure when compared to other factors. Threshold Indicator Taxonomic ANalysis showed significant negative threshold responses by some species to small levels of development (<0.15 wells km^?2), whereas positive thresholds were less distinct. Some native and imperilled species could be disproportionately affected if future oil and gas development proceeds in a manner that will impact aquatic resources. Although existing development has not substantially influenced regional fish assemblage structure, it appears to affect a subset of species. Understanding assemblage‐level responses to development can help land managers determine appropriate development levels, prioritise areas for monitoring associated with future development and identify where land protection measures may be needed to offset potential risks.     

加快城乡统筹，推进我国农垦体制创新与经济发展的研究与思考

“十一五”以来，我国农垦加快体制机制改革、结构调整和经济增长方式的转变的步伐，参与市场竞争，努力提升企业和产品竞争力，经济社会事业发展较快，对国家的贡献提升，职工收入、生活质量明显提高和改善，示范引领作用不断增强。本文针对农垦体制机制创新进展滞缓，战略定位与发展方向不明，经济增长方式转变和结构调整缺乏资本、人才、技术的支撑，没有处理好改革、发展、稳定、民生的关系，投资匮乏，发展后劲不足，人才短缺和劳动力素质低下的现状，提出在未来农垦体制机制创新中要特别关注改革方向、目标设定与评估，改革要在现行法律法规的框架内运作，改革时机的选择，处理好改革发展稳定与民生的关系，调整好内部利益分配关系，自觉融入区域经济，与地方协同发展等问题。为了促进农垦的发展，建议国家加大对农垦体制机制创新、现代农业建设、国有农场土地资源的保护、社会保障体系的完善等财政和政策的支持力度。     

Gar biology and culture: status and prospects

Many lepisosteid populations in North America have declined and many are now threatened as a consequence of habitat loss and alteration and commercial and sport overfishing. Over the last two decades, morphological, histological and molecular studies allowed distinguishing between different phases of development and the nutritional condition of larvae. Ontogeny of the digestive enzymes of gar larvae indicated the possibility to feed them artificial feeds since early developmental stages. An in vitro digestibility system to test different feed ingredients has been used. Important characteristics of artificial diets were identified through different feeding experiments. Endocrinological studies showed the feasibility of altering larval development and the digestive capacity of larvae. Cloning of gar growth hormone opened new avenues to enhance growth in the gars. Plasmatic vitellogenin was isolated and purified, to develop a competitive enzyme‐linked immunosorbent assay, which allowed the straightforward separation of males from females to establish appropriate proportions for reproduction and also was used to evaluate hormonal protocols to induce gonad recrudescence and spawning. This review analyzes the biology, ecology and physiology of different gar species as a basis for their domestication, mass production of larvae for repopulation experiments and for the culture of commercial‐size gar.