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1.
2016年5月河北省秦皇岛市昌黎县某海水养殖基地半滑舌鳎突发大批死亡,为了确定引起死亡的病原菌,无菌采集心血进行病原菌分离鉴定,16S rDNA基因序列分析与GenBank中公布的美人鱼发光杆菌参考株序列同源性为99.6%,被鉴定为美人鱼发光杆菌;进一步通过生化特性分析,被确认为美人鱼发光杆菌美人鱼亚种。动物回归试验结果表明,其对舌鳎鱼具有很强的致病性,其LD_(50)为3.1×10~4CFU/mL,且对哺乳动物具有致病性。药敏试验结果显示,分离菌对诺氟沙星、恩诺沙星、环丙沙星,乙酰甲喹高度敏感;对多西环素、阿米卡星中敏感;对庆大霉素、头孢曲松、替米考星等不敏感。  相似文献   
2.
介绍了6S管理的内涵、实施方案,以及引入6S管理的必要性与可行性。针对当地个体食品生产者生产馒头的现状,引入6S管理体系,取得了良好的效果。  相似文献   
3.
The first isolation of Tenacibaculum maritimum from wedge sole, Dicologoglossa cuneata, is reported. The pathogen was recovered from ulcers of cultured fish, from three different outbreaks. The six isolates obtained were biochemically and serologically characterized and diagnosis was confirmed by polymerase chain reaction using specific primers and partial 16S rRNA gene sequencing. The isolates constituted a homogeneous phenotypic group; however, they belong to two of the different serotypes described within this species. A virulence evaluation of the isolates using Wedge sole fry was also performed.  相似文献   
4.
A study was undertaken to determine the effect of various dietary carbohydrate‐to‐lipid ratios on growth performance, whole‐body composition and tissue lipid content in Senegalese sole (Solea senegalensis) juveniles. Data on the dietary regulation of key hepatic enzymes of the lipogenic and glycolytic pathways (glucose‐6‐phosphate dehydrogenase, G6PD; malic enzyme, ME; fatty acid synthetase, FAS; pyruvate kinase, PK and glucokinase, GK) were also generated. Four isonitrogenous (crude protein: 52% dry matter (DM)) diets were formulated to contain one of two lipid levels (11% and 21% DM). Within each dietary lipid level, the nature of the carbohydrate fraction (raw or extruded peas) was varied. Triplicate groups of 54 sole (initial body weight: 23.6±1.2 g) were grown in recirculated seawater over 67 days. Fish were fed using automated feeders. At the end of the study, whole‐body, liver, viscera and muscle samples were withdrawn for analyses. During the experimental period, the mean fish weight about doubled in all treatments. No significant differences were found in growth performance (ranging from 1.1% to 1.4% body weight day?1) among dietary treatments. High‐fat diets increased whole‐body fat content. Similarly, daily fat gain ranged from 0.54 to 0.78 g kg?1 day?1 and highest values were found in fish fed high‐lipid diets. Dietary treatments also affected tissue lipid content (liver, viscera and muscle), with highest values in fish fed high‐fat diets. The nature of dietary carbohydrates had little influence on performance criteria, but affected tissue lipid deposition. The activities of G6PD, ME and FAS were depressed by elevated levels of dietary lipid, confirming the inhibitory effect of dietary fats on lipid biosynthesis. At both dietary lipid levels, ME and FAS activities were little affected by dietary carbohydrate. Activities of PK and GK were not affected by the starch level of the diets. In Senegalese sole juveniles, the lipogenic pathway is more susceptible to modulation by dietary means (particularly through lipid intake) than the glycolytic pathway.  相似文献   
5.
为研究HIRA基因在半滑舌鳎胚胎发育中的作用及其组织差异表达,以半滑舌鳎为研究对象,采用同源克隆策略从其精巢中分离了长度为764bp的HIRA部分cDNA序列,该片段编码254个氨基酸,具有5个wD结构域。对氨基酸进行比较发现,半滑舌鳎HIRA与比较物种的氨基酸序列具有很高的同源性,与红鳍东方纯亲缘关系最近。实时定量PCR分析发现,HIRA mRNA在多细胞期到原肠胚期的表达量较高,表明HIRA对胚胎发育起重要作用;HIRA在不同组织中表达差异显著,其中在性腺中表达最高,推测HIRA在维持性腺的功能方面有一定作用。  相似文献   
6.
Eggs from a F1 cultured broodstock of sole were compared with eggs from wild‐caught breeders throughout one spawning season, to evaluate if egg quality may be affected by culture‐related conditions. Fourteen batches of eggs from cultured broodstock and 17 batches from wild‐caught sole were compared with respect to fatty acid (FA) composition, egg size, fertilization rate and hatching rate. Based on a multivariate analysis of the FA profiles, it was possible to discriminate between culture and wild inheritance. Eggs from cultured broodstock had high levels of C20:1(n‐9), C18:2(n‐6) and C18:3(n‐3), whereas eggs from wild fish had high levels of C16:1(n‐7), C20:4(n‐6) and C20:5(n‐3). Differences in FA profiles were most likely related to dietary differences. Fertilization and hatching rates were generally low and lowest in eggs from cultured broodstock, but not related to FA composition. Larval growth of one batch from each group was compared. Larval growth was not correlated to broodstock origin, FA composition or egg or larval size. However, larval survival was significantly lower for larvae from cultured broodstock.  相似文献   
7.
In the view of an urgent necessity to improve the quantity and the quality of farmed fish species, there is a strong need to improve our basic knowledge on the effects of first feeding during the developmental stages of fish larvae. High mortality, mainly due to food deprivation or inappropriate food quality, has been observed in many larval fish species, but knowledge about the morphological, biochemical and molecular processes related to this topic is still poorly understood. The understanding of the early larval ontogeny as well as the larval nutritional requirements and the molecular and cellular mechanisms elicited by fish larvae during food deprivation and starvation are thus of primary importance. At this regard, this study investigates, in Dover sole larvae, the effects of starvation and starving/re‐feeding procedures at a morphological, histological, biochemical and molecular level. The results evidenced that starved larvae progressively decrease in growth, lipid content, affected their gastrointestinal tract and muscle development and increased cortisol and heat shock protein 70 levels. On the contrary, starved and re‐fed larvae showed, after the restoration of a favourable feeding condition, a compensatory growth. In conclusion, this is the first study analysing through a multidisciplinary approach the effects of food deprivation on the development of an important economic species, the Dover sole.  相似文献   
8.
根据2001及2003~2005年农业部渔业局金枪鱼延绳钓科学观察员获得的生物学数据,对主要捕捞对象大眼金枪鱼和黄鳍金枪鱼的生物学特征进行初步分析。结果显示,大眼金枪鱼叉长范围63~206 cm,加工后净重范围9~138 kg。黄鳍金枪鱼叉长范围是97~176 cm,加工后净重范围14~80 kg。两种类雌性个体所占比例各月差异较大,平均约40%。大眼金枪鱼和黄鳍金枪鱼净重与叉长关系分别是W=2.0241×10-5L2.9503,W=2.2281×10-5L2.9079。  相似文献   
9.
Current shrimp quality evaluation is a subjective sum of visual, smell and texture characteristics, and the manual determination of count and uniformity ratio of a sample batch. The automation of this process is desirable for a more rapidly and objectively repeatable evaluation. As a first step towards this goal, the count and uniformity ratio of whole, headless, peeled-tail-on, and peeled-tail-off tiger and white shrimp were evaluated by a machine vision procedure. The experimental weight and view area were correlated by three different equations (linear, power, and forced-power curves) to find the best correlation. The pixel intesities as it relates to lightness-darkness values were also correlated to see if different forms and species could be distinguished by this method. Data, equations and statistics for the correlations are presented.  相似文献   
10.
森林案件涉案伐倒木材积惟一性的探讨   总被引:1,自引:1,他引:0  
材积是盗伐、滥伐等森林案件定性和处罚的主要依据,要求具有惟一性。用马尾松、杉木和杨树的伐倒木资料,分别按不同的计算方法计算其材积,结果表明:在3种树种中,中央断面区分求积式(区分段段数为5以上)的材积都最接近实际材积,误差也都较小,可作为森林案件中涉及伐倒木材积的惟一认定结果。  相似文献   
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