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1.
Seasonal Changes in the Milt Quality of Waigieu Seaperch,Psammoperca waigiensis: Implications for Artificial Propagation
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Milt quality of Waigieu seaperch was sampled at the beginning, the middle, and the end of the spawning season to assess if the sampling season has an effect on milt quality parameters. The milt volume and total sperm production were higher at the middle of the spawning season while the sperm concentration in milt was significantly higher at the beginning and the end of the spawning season. Sperm morphology and the major parameters of seminal plasma (pH, total protein, Mg2+, or Ca2+ concentrations) did not differ throughout the spawning season. The concentrations of Na+ and the osmolality increased throughout the spawning season. The percentage of motile cells did not differ during the spawning season while the duration of sperm motility (swimming duration) and velocity (swimming speed) were significantly different during the spawning season. The fertilization rate (75.7 ± 6.8%) and hatching rate (56.5 ± 3.1%) at the middle of the spawning season were higher than at the beginning and end periods. Results indicated that milt quality parameters and fertility success in the middle of the spawning season were higher compared to earlier and later sampling dates. Thus, we recommend collecting milt during this time for maximal fertilization and hatching success. 相似文献
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为评价警犬的狂犬病免疫效果,了解影响免疫效果的因素,2017年在云南、贵州、四川三省部分地区免疫狂犬病疫苗的警犬中随机抽样,采用荧光抗体病毒中和试验(FAVN),检测血清中狂犬病病毒中和抗体效价。结果显示,共抽检187只警犬,中和抗体阳性127只(≥0.50 IU/m L),总体免疫合格率为67.91%,其中云南、贵州、四川3省的免疫合格率分别为57.14%、68.33%、76.06%。结果分析表明,警犬狂犬病免疫合格率与犬的年龄、免疫次数、疫苗类型等因素有关,而与性别和品种无关。建议完善警犬免疫程序,加大血清中和抗体监测力度,对不合格警犬及时加强免疫;对每个影响因素进行连续性分析,以确定影响警犬狂犬病免疫合格率的具体因素。 相似文献
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Chang‐Hoon Shin Hien Thi Dieu Bui Samad Rahimnejad Ji‐Hoon Cha Byung‐Woo Yoo Bo‐Kyeun Lee Hyung‐Jin Ahn Soo‐Il Choi Yun‐Jeong Choi Yong‐Ho Park Jeong‐Dae Kim Kyeong‐Jun Lee 《Journal of the World Aquaculture Society》2014,45(3):258-268
This study was conducted to evaluate the effects of dietary supplementation of Barodon, an anionic alkali mineral complex, on growth, feed utilization, humoral innate immunity and disease resistance of olive flounder. A basal experimental diet was used as a control and supplemented with 0.1, 0.2, 0.3, 0.4, or 0.5% Barodon. Triplicate groups of fish (26.4 ± 0.2 g) were fed one of the diets to apparent satiation twice daily for 10 wk. The growth performance was enhanced (P < 0.05) linearly and quadratically in fish fed diets containing Barodon compared with that in fish fed the control. Feed utilization was significantly improved by Barodon supplementation. Serum lysozyme and antiprotease activities were increased quadratically in Barodon fed groups. Also, significantly higher superoxide dismutase activity was found in Barodon‐fed fish. Dietary supplementation of 0.1–0.3% Barodon resulted in significant enhancement of fish disease resistance against Streptococcus iniae. The findings in this study indicate that dietary supplementation of Barodon can enhance growth, feed utilization, innate immunity, and disease resistance of olive flounder and that the optimum level seems to be 0.1% in diets. 相似文献
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中蜂囊状幼虫病是一种由中蜂囊状幼虫病毒引起的严重威胁中蜂健康的传染性疾病。目前由于该病尚无有效的药物治疗方式,因此,预防与及时检测对于遏制该病传播显得尤为重要。本文主要从临床诊断、分子生物学和免疫学方面总结中蜂囊状幼虫病检测与鉴定的方法,包括形态诊断、RT-PCR技术、实时荧光定量PCR、巢式PCR、胶体金免疫快速诊断技术、ELISA、血清学技术和基因芯片等,为中蜂囊状幼虫病毒检测方法的改进和优化提供参考。 相似文献
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为了解山东省规模猪场非洲猪瘟防控成本和效益变化情况,2020年上半年从母猪繁殖性能、育肥猪生产性能、仔猪及饲料购买费用、医疗技术投入费用、防控成本以及收入和利润等方面,对抽检的19家规模养猪场开展问卷调查,并对调查结果分别与2019年和非洲猪瘟疫情发生前年份(以下简称正常年份)进行统计对比。结果显示:2020年上半年规模猪场能繁母猪存栏量同比增加200.1%,比正常年份增加372.8%;育肥猪年出栏量同比增长720.7%,比正常年份增长527.0%。仔猪平均购买价格同比增长49.2%,比正常年份增长167.8%;医疗防疫费同比增长4.1%,比正常年份增长11.6%;改造或新建防控设备设施投入大幅增加,其中智能化系统、散装饲料塔、空气过滤系统、外墙防护设施的升级新建投入费用均超过1 600万元;血清学检测费用同比增加3.4%;病原学检测费用同比增加103.4%。断奶仔猪平均售价同比增长59.9%,比正常年份增长148.4%;育肥猪平均售价同比增长24.4%,比正常年份增长127.0%;净利润同比增加63.2%,比正常年份增加1 125.8%。结果表明,山东省规模猪场在防控非洲猪瘟疫情方面的投入明显加大,但生猪产能显著提升,生猪养殖收益大幅增加,因而生猪生产恢复趋势利好。 相似文献
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XIANG Dang~ 《保鲜与加工》2004,(5):147-150
This paper studied how the auction processis influenced by bankruptcy probability, bankruptcy cost, and the corporatetax rate. The study found thatthe bidding price of the management is negatively associated with bankruptcy cost and probability, and positivelyassociated with the corporate tax. However, the expected profit of the outside investor is positivelyassociated with bankruptcy cost and probability, and negatively associated with the corporate tax. When the bankruptcy cost and probabilityis high enough, the acquisition market would be totally inefficient. 相似文献
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为进一步提高粮食生产科技含量,稳定粮食生产能力,近几年来浙江省确定在全省667khm2商品粮基地中实施以农业新品种、新技术和新农机为主要内容的“三新技术”配套项目。上虞市于2002年度获得了该项目的建设计划,并按照省定要求,联系本地实际,及时制定了项目实施方案,落实地方配套资金,签订项目承包合同,加强项目的管理,确保了项目的建设质量,产生了良好的社会和经济效益。该项目的实施既促进了农业龙头企业的生产发展,又起到了较好的示范和带动作用,也为提高上虞市部分农产品的经济效益提供了较好的条件,有着广阔的市场发展前景。 相似文献