猪囊尾蚴病的检疫与防治

猪囊尾蚴病也称猪囊虫病,是由有钩绦虫的幼虫引起的一种人畜共患的寄生虫病。本病对人体健康和公共卫生危害极大,应大力开展预防、控制和净化工作。从片角乡2005—2008年猪囊尾蚴病检出情况进行分析,提出了采取改变生猪饲养方式和改善环境卫生;做好检疫(验);实施预防性驱虫等防治措施,对降低猪囊尾蚴病的感染率具有明显的效果。     

浅谈猪囊尾蚴病的检疫与防控措施

<正>猪囊尾蚴病,群众俗称:"囊虫猪"或"米虫猪",病原体是寄生在人体内的猪带绦虫的幼虫—猪囊尾蚴,它可寄生于猪的肌肉中,大量寄生可使肌肉不能食用而销毁,人误食含有猪囊尾蚴的肉品,可发生绦虫病,虫卵移行     

猪副嗜血杆菌病的菌苗防制

猪副嗜血杆菌病发病特点表现为多发性浆膜炎、关节炎和脑膜炎。疾病主要发生于保育猪阶段,目前给我国猪群带来很大威胁,随着猪繁殖与呼吸综合征的流行,猪副嗜血杆菌病给猪群造成的损失比以往更为严重,而爆发性的猪副嗜血杆菌病也比以往更为普遍。由于药物滥用导致猪副嗜血杆菌的耐药性越来越严重,当务之急是如何有效控制本病,文章就当今副猪嗜血杆菌病的防治提出有效的方法。     

猪囊尾蚴病的防治

正猪囊尾蚴(cysticercus cellulosae)属于一种寄生在人体内的猪带绦虫(Taenia solium)的幼虫---猪囊尾蚴(Cysticercus cellulosae),属带科的带属。按照猪带绦虫宿主分类可以分为中间宿主和最终宿主,其中猪和野猪、骆驼、猫、以及狗都可以被视为是中间宿主,而人则可以被视为是最终宿主。对猪囊尾蚴病的检查和防治也是肉品卫生检验的关键内容之一。1病情概述猪囊尾蚴是一种寄生在猪体内的病虫,很多人将有这种病虫的猪肉称     

猪气喘病的综合防治

<正>猪气喘病又称猪肺炎支原体病和猪喘气病,是由猪肺炎支原体引起猪的一种慢性接触性呼吸道传染病,主要临床症状是咳嗽和气喘。综合防治的关键技术包括:疫苗免疫、检疫隔离、药物防治、卫生消毒、早期断奶、自繁自养、全进全出等综合措施。1流行特点本病流行广泛,虽然死亡率不高,但是病程长,使猪生长停滞,给养猪业带来严重经济损失。猪气喘病只感染     

猪病防治的误区与应对策略

随着人民经济水平和消费实力的提升,养猪业得到了很大的发展,但同时复杂的外界环境增加了猪病发生的风险。一些养猪场在防治猪病的过程中存在一些问题导致防治效果不明显。分析现阶段养猪场在猪病防治时常有的一些误区现象,提出相应的合理应对策略。     

陕西省当前猪病发生特点、流行趋势及防控对策

目前陕西省养猪业发展迅速,但是由于对猪病缺乏有效的防控手段,致使猪病种类繁多难以控制,给陕西养猪业造成重大的经济损失。从陕西省常见猪病的分类、猪病的流行现状、猪病流行的原因分析、猪病防控对策等4个方面综述了陕西省当前猪病防控存在的问题及如何控制猪病的发生,为陕西省猪病的防控提供参考资料。     

高致病性猪蓝耳病的流行和防治方法

生猪养殖业是国家经济发展和社会进步的重要组成部分,促进人民生活水平提高。高致病性猪蓝耳病严重制约着生猪养殖业的发展。简单介绍猪蓝耳病概念、传播途径和临床表现,提出有效防治措施。     

浅谈猪常见传染病的诊断与防治

简要介绍了猪口蹄疫、猪瘟、猪蓝耳病、猪链球菌病、猪附红细胞体病、猪气喘病等常见传染病的临床诊断方法和防治技术。     

副养嗜血杆菌病的防控措施

目前,猪副猪嗜血杆菌病已经在全球范围影响着养猪业的发展.文章介绍了副猪嗜血杆菌病临床特征、诊断方法和防治要点和具体方法,提出应对本病引起高度重视.     

Effect of the slaughter method on the quality of raw and smoked eels (Anguilla anguilla L.)

Eels (Anguilla anguilla L.) were slaughtered using two procedures. The commercial method consisted of desliming the fish in dry salt followed by evisceration. The alternative method consisted of stunning and killing in water with a combination of electricity and oxygen removal. Eels slaughtered as commercially exhibited aversive reactions and consequently a higher level of muscular activity before death. In raw fillets, differences appeared clearly between the two batches. The alternative slaughter by electricity and gas led to redder, firmer flesh with a higher pH. Myofibrillar proteolysis, lipid oxidation and loss of freshness (as evaluated by K‐value) were reduced. After hot‐smoking, which is a process that greatly modifies the fish flesh properties, differences between batches were less pronounced. However, eels slaughtered by the alternative method were characterized by a higher pH and a redder colour of the dark muscle, a desirable property form a commercial point of view. When assessed by sensory difference tests, appearance seemed to be the only attribute that allowed panellists to discriminate the two batches. Overall, it is concluded that slaughter by electricity and gas improved the quality of raw and smoked eels compared with the commercial method.     

Serological comparison of selected isolates of Aeromonas salmonicida ssp. salmonicida

Abstract. Eight isolates of Acronionus salmonicida ssp. salmonicida were collected during furunculosis epizootics in North American Pacific coast states and provinces. Both virulent and avirulent forms of each isolate, confirmed by challenge and electron microscopy, were examined. Serological comparisons by cross-absorption agglutination tests revealed no serological differences between isolates. Using the double diffusion precipitin test, a single band was observed when antigen from a sonicated virulent strain was reacted with antiserum against a sonicated, virulent strain absorbed with homologous, avirulent strain. The presence of the single band was eliminated by excess sonication.     

Determination of Count and Uniformity Ratio of Shrimp by Machine Vision

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.     

Patterns of foraging and distribution of bluegill sunfish in a Mississippi River backwater: influence of macrophytes and predation

Abstract— We studied the trophic interactions and spatial distributions of bluegills Lepomis macrochirus and largemouth bass Micropterus salmoides in a macrophyte bed in Lake Onalaska, a backwater lake in the upper Mississippi River. The diets of adult and age-0 bluegills were similar and changed seasonally probably in response to changes in life stages of macroinvertebrates (i. e. emergence of winged adults). Diets and diel patterns of abundance of bluegill suggest that age-O and adults were feeding in the vegetated, littoral zone. Predation by age-O largemouth bass appears to influence use of vegetated habitat by age-0 bluegills. In summer, when most age-O bluegills were vulnerable to predation by age-O largemouth bass, bluegill abundance was strongly correlated with vegetation biomass. In October and November, piscivory by age-O largemouth bass was limited by gape. Consequently, the relationship between the abundance of age-O bluegills and vegetation biomass was weakened because predation risk by age-O largemouth bass was reduced.     

淇河鲫IL-8原核表达系统的构建及多克隆抗体的制备与鉴定

为揭示淇河鲫(Carassius auratus var.Qihe)白细胞介素-8(interleukin-8,IL-8)的功能,本研究构建了原核表达系统,并制备了兔抗鲫IL-8多克隆抗体。首先采用RT-PCR法扩增淇河鲫IL-8基因编码序列中不含信号肽的基因片段,克隆到pET-32a(+)载体后转化入Rosetta菌株构建原核表达系统。经IPTG诱导表达出相对分子质量约27.8 kD的目标融合蛋白。将纯化的融合蛋白免疫家兔制备多克隆抗体,效价达1︰10~5。经免疫亲和层析纯化的抗体能特异性识别重组和天然的淇河鲫IL-8蛋白。比较不同组织的免疫组化和荧光定量PCR结果,IL-8蛋白量和mRNA的表达量在不同组织间变化趋势一致,在肌肉、脾和头肾均检测到较高的表达量,肠道的表达量较低。本研究为进一步探讨淇河鲫IL-8的生物学功能奠定了基础。     

Potential of Cellulase From Bacillus megaterium for Hydrolysis of Sargassum

Bacterial cellulase can be a promising biotechnological approach in seaweed degradation to facilitate extraction of bioactive molecules. In the present study, bacterial cultures were isolated from marine and terrestrial samples and screened for cellulase production. The selected cultures were grouped by random amplification of polymorphic DNA (RAPD) profiling, and the cultures showing a distinct banding pattern were identified by 16S rDNA sequence analysis. Cellulase from Bacillus megaterium (CB-sw1-I), a native isolate, was purified by ion-exchange chromatography with a purification fold of 6.91 and specific activity of 1.66 U. The purified enzyme with molecular weight of 43 kDa was optimally active at pH 6.0 and temperature of 60°C. The potentiality of enzyme in degradation of Sargassum thallus was evident with an increase in reducing sugar. Morphology of the thallus after 10 days digestion observed by scanning electron microscope also provided additional evidence for degrading ability of the enzyme. This enzyme could subsequently be used in hydrolysis of seaweed for extraction of bioactive molecules.     

Habitat analysis of the commercial tuna of the Eastern Tropical Pacific Ocean

We have extracted information on the habitats of bigeye (Thunnus obesus), skipjack (Katsuwonus pelamis) and yellowfin (Thunnus albacares) in the Eastern Tropical Pacific Ocean by matching the spatial‐temporal distribution of catch and effort of purse seine and longline fleets collected by the Inter‐American Tropical Tuna Commission with oceanographic conditions and subjecting the matched data to Quotient Analysis and General Additive Models (GAMs). These analyses yielded the following results. The habitats defined by the GAM analysis of young fish differ significantly between two periods, one before and one after the introduction of fish aggregation devices (FADs). This was not true for the older fish caught by longline. We speculate that these changes were caused by the extensive use of FADs. Younger bigeye and yellowfin caught by the purse seine fleet have a different preference of environmental variables compared to older fish caught by longline. This is to be expected since tuna of different age groups have different sizes, metabolic capabilities and swimming skills. Moreover, as revealed by GAMs, the habitats of young fish differ between species to a much larger degree than those of older fish. Our results indicate the fundamental differences between fishing methods, targeted species, and operating region of the two fisheries. Specifically, young bigeye occupy equatorial waters farther from the coast and where the hypoxic layer is deeper, young skipjack occupy more productive waters associated with equatorial and coastal upwelling, and young yellowfin occupy broad areas where waters are underlain by a shallow hypoxic layer.     

宽礁膜原生质体的分化与发育

为缩短传统育苗时间,开发室内种质保存技术,满足大规模栽培苗种需求,实验用4%的果胶酶和2%纤维素酶混合,将来自于不同月份和不同藻体部位的宽礁膜切段,分别在相同条件下解离成原生质体,详细研究了这些不同部位和不同生长时期细胞的再生、分化和发育途径。根据体细胞后代的外形、有无假根、有无公共膜、细胞大小和排列方式,以及它们最终的发育分化趋势,将宽礁膜原生质体发育方式分为8种结果,既可形成体细胞,也可形成生殖细胞。形成体细胞的发育途径又分3种类型7种结果,即细胞团、畸形苗和正常苗3种类型,其中发育成细胞团的类型又分为规则细胞团和不规则细胞团2种结果,发育成畸形苗的类型又分为假根为主的畸形苗、有类假根的畸形苗、无假根的畸形苗和管状畸形苗4种结果。各种发育类型与藻体的日龄、大小及部位有关,其原生质体直接发育形成正常形态藻体的发育方式只是8种发育结果的一种。     

Effect of Astaxanthin on the Pigmentation of Goldfish Carassius auratus

The optimal dosage of astaxanthin for goldfish Carassius auratus was determined by feeding a series of diets containing 0, 25, 50, 75, and 100 mg of astaxanthin/kg of diet for 4 wk. The pigmentation on fish skin was measured by visual assessment against a color chart and by counting chromatophores produced in the dermis layer of fish skin. Both criteria showed that 36–37 mg/kg astaxanthin was the optimal dosage to stimulate fish color. A 4-wk observation after this experiment demonstrated that fish color stimulated by dietary astaxanthin was stable in its intensity. Therefore feeding astaxanthin could be a suitable way for goldfish producers to stimulate color among fish grown in an algae-free environment. The survival rate of fish fed diets with astaxanthin was significantly higher than fish fed diets without astaxanthin. However, there was no significant effect of astaxanthin on fish weight gain.