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1.
选择中国大陆最早分离的H9N2亚型禽流感病毒(avian influenza virus,AIV)A/Chicken/Guangdong/SS/94(H9N2)(缩写为SS株)和1998年大流行时期分离的H9N2亚型AIVA/Chicken/Shanghai/F/98(H9N2)(缩写为F株)为研究对象,对其在SPF鸡体内的复制能力和传播途径特性比较后发现,F株在4周龄SPF鸡气管中的复制能力高于SS株,F株可以经气溶胶传播途径传播,SS株不能经气溶胶传播途径传播;利用反转录-聚合酶链反应(RT-PCR)方法获取F株和SS株的HA和NA基因的cDNA,序列分析得知,F株和SS株的HA和NA基因的同源性分别是96.6%和98.1%;HA基因的裂解位点氨基酸序列都是PARSSR↓GL,但有5个氨基酸的差异,即166位N(F)→D(SS)、198位A(F)→V(SS)、217位V(F)→I(SS)、335位G(F)→R(SS)、504位L(F)→S(SS);2株病毒的NA基因在63~65位都存在氨基酸缺失,但在NA基因红细胞吸附位点的氨基酸序列不同,分别是IKKDSRSG(F)和IKEDLRSG(SS)。F株和SS株的传播特性差异是否与其表面基因序列有关,有待进一步研究。  相似文献   

2.
2005年9月份,大庆市红岗区个体养鹅专业户送检6只病死的5月龄左右隆昌鹅和长白鹅,经过实验室诊断确诊为矛形剑带绦虫与背孔吸虫混合感染。矛形剑带绦虫属膜壳科  相似文献   

3.
禽类的起源、演化及我国主要家禽品种类型与分布   总被引:1,自引:1,他引:0  
家禽是重要经济价值动物.本文从禽类种群进化学说出发,简介了禽类的起源、演化、动物学分类和家禽的驯化(养)与品种的形成,并对我国主要家禽(鸡、鸭、鹅)地方品种和培育品种(配套系)的分布与类型作了描述,以期为研究我国家禽起源系统,保护与利用我国家禽品种,促进家禽生产可持续发展提供参考.  相似文献   

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5.
近年以来,由于市场因素的刺激,生猪的存养量大幅上升,再加上由于流通环节较多,流通非常频繁,流通距离越来越远。这对繁荣经济,增加养殖效益起了重要的推动作用,但也同时给疾病的感染和传播创造了有利条件,给猪病的防治带来了困难。有的猪场感染了传染病后,由于治疗不及时不得法,而造成了惨重的经济损失。2008年7月中旬,我街道一养猪户因盲目从外地购进中猪,发生猪病疫情,引起猪只连续死亡,造成一定的经济损失。根据流行病学、临床症状、剖检变化和实验室诊断,诊断该病为猪链球菌病和猪伪狂犬病混合感染,现报告如下。  相似文献   

6.
1前言1.1鸡白冠病鸡白冠病是由卡氏住白细胞原虫寄生于鸡的红细胞和单核细胞而引起的鸡的贫血性疾病。吸血昆虫蚋和库蠓叮咬鸡引起传播,是主要的传播媒介,一般在夏末和秋季多发,由于夏季降雨量较大,部分沟渠积水,库蠓和蚋多孳生,因此在多雨水涝的年份发病率明显增高。1998年中国从南到北发生洪涝灾害,吸血昆虫的孳生格外严重,出现了一个白冠病多发年,而后两年发病稍轻,并有地区性,今年8月中旬以来白冠病的发病呈抬头趋势,有一定的死亡率,对蛋鸡产蛋率也会引起一定程度的降低,应引起养鸡户的重视。1.2鸡痘鸡痘也是…  相似文献   

7.
Crown width, height and buccal surface areas were measured on heads or skulls of four dogs and four cats, and were compared with similar measurements on models of human dentition. Buccal surface area variability was greater in dogs and cats than in humans, and teeth of cats were smaller. Horizontal (gingival and occlusal halves) and vertical (mesial, middle, and distal thirds) buccal surface area variability was also greater in canine and feline teeth compared with human teeth. This increased variability suggests the need for testing of reliability and repeatability of scoring when using plaque and calculus indices based on horizontal or vertical segmentation. Buccal surface area variability between teeth also prompts questioning the validity of equal weighting of smaller, irregularly-shaped teeth when calculating a mean mouth score. Whether equal or more reliable results would be obtained from scores of whole teeth in comparison with segmentation indices used currently has yet to be determined.  相似文献   

8.
1. The repeatability and heritability of growth inhibition by egg albumen of two major pathogenic bacteria, a Gram-negative (Salmonella Enteritidis) and a Gram-positive (Staphyloccocus aureus) and of two antimicrobial albumen proteins, lysozyme and ovotransferrin, were estimated in commercial pedigree hens. 2. Repeatability was evaluated in 100 egg-type hens at the beginning, middle and end of the laying cycle on eggs collected for 3 weeks. Heritabilities were estimated at 36 to 40 weeks of age on 400 pedigree hens (2 eggs/hen), which were the offspring of 25 sires each mated with 4 dams. Ovotransferrin and lysozyme were quantified by ELISA. Salmonella Enteritidis (S.E.) and Staphyloccocus aureus (S.A.) were inoculated into a sample of sterilised albumen and enumerated after incubation. 3. Total protein content in albumen decreased with age of laying hens, whereas there were increases in lysozyme or ovotransferrin concentrations and in the bacteriostatic effect of albumen. 4. Repeatability for bacterial growth in albumen ranged from 0.29 to 0.39 for the number of S.E. (log cfu/ml) one day post inoculation (p.i.) but was lower and more variable at 5 d p.i. or for S.A. number. It ranged from 0.27 to 0.38 for S.E. and S.A. number at the mid period of the laying cycle. Repeatabilities were low and variable for total egg albumen protein or lysozyme and ovotranferrin concentrations (0 to 0.22). 5. Negative phenotypic correlations were observed between lysozyme concentrations and S.E. number but that between lysozyme and S.A. number was not significant. 6. Heritabilities were low (0.01 to 0.09) for protein traits. They were 0.11 for S.A. number and 0.16 for S.E. number one day p.i. 7. It appears to be more efficient to select on global bacterial growth than on specific antimicrobial proteins. The most promising trait is the number of S.E. one day p.i.  相似文献   

9.
OBJECTIVE: To evaluate lactoferrin and lysozyme content in various ocular glands of bison and cattle and in tears of bison. SAMPLE POPULATION: Tissues of ocular glands obtained from 15 bison and 15 cattle and tears collected from 38 bison. PROCEDURE: Immunohistochemical analysis was used to detect lysozyme and lactoferrin in formalin-fixed, paraffin-embedded sections of the ocular glands. Protein gel electrophoresis was used to analyze ocular glands and pooled bison tears by use of a tris-glycine gel and SDS-PAGE. Western blotting was used to detect lactoferrin and lysozyme. RESULTS: Immunohistochemical staining for lactoferrin was evident in the lacrimal gland and gland of the third eyelid in cattle and bison and the deep gland of the third eyelid (Harder's gland) in cattle. Equivocal staining for lactoferrin was seen for the Harder's gland in bison. An 80-kd band (lactoferrin) was detected via electrophoresis and western blots in the lacrimal gland and gland of the third eyelid in cattle and bison, Harder's glands of cattle, and bison tears. An inconsistent band was seen in Harder's glands of bison. Lysozyme was not detected in the lacrimal gland of cattle or bison with the use of immunohistochemical analysis or western blots. Western blots of bison tears did not reveal lysozyme. CONCLUSIONS AND CLINICAL RELEVANCE: Distribution of lactoferrin and a lack of lysozyme are similar in the lacrimal gland of cattle and bison. Differences in other tear components may be responsible for variability in the susceptibility to infectious corneal diseases that exists between bison and cattle.  相似文献   

10.
Comparison of the electrophoretograms of normal canine plasma and serum revealed a greater concentration of the beta3-fraction in plasma due to the presence of fibrinogen. When serum or plasma of hemolyzed canine blood was analyzed electrophoretically, there were slurring of the beta-globulin peaks due to the presence of free hemoglobin and increases in alpha2-globulins due to the formation of the haptoglobin-hemoglobin complex.  相似文献   

11.
本文系统地回顾了近60年以来国内外乡土灌草青贮利用与牛羊健康饲喂的研究现状与进展。通过对已有研究文献的年度分布、研究内容与研究区域进行分析,结合饲草青贮技术领域、草食畜牧业领域以及社会发展的背景,将乡土灌草青贮与牛羊健康饲喂划分为3个阶段,20世纪50年代到80年代末期为萌芽阶段、20世纪80年代末期到21世纪初期为缓慢增长阶段、21世纪初期至今为快速增长阶段。其次,根据研究内容从理论研究、监测评价、技术示范、技术研发4个方面进行归纳总结,分析了各分支领域的主要成果与关键问题,提出下阶段应重点研究的内容,应加强对乡土灌草饲料生产与牛羊健康饲喂的研究,综合提高饲料能量与蛋白质的利用率,尽可能改善牛羊的能氮平衡,促进畜牧业和饲料加工业的发展。  相似文献   

12.
Over a period of about 12 years, 30 abnormal Schistosoma mattheei cercariae were found among a total of approximately 2.8 million examined. Initially seven were recovered from about 1.02 million (0.0007%), which were examined individually while being counted with the aid of a stereoscopic microscope. Subsequently, on the strength of relatively high percentages of abnormal individuals recovered when counting cercariae that failed to penetrate into oxen, it appeared that the morphologically abnormal cercariae were unable to swim and would mostly sediment out of a suspension while most of the normal cercariae would remain swimming. This surmise is supported by recovery of 23 morphologically abnormal cercariae (0.001%) from about 1.8 million, by examining the sediment after the cercarial suspension had been left standing undisturbed in glass measuring cylinders. The abnormalities ranged from aberrant tails only (e.g. an underdeveloped tail, or different degrees of schism) or aberrant heads only, to abnormalities of both the heads and tails. A suggested schematic classification of abnormal cercariae is presented. A young, adult hamster was exposed to eight S. mattheei cercariae with complete schism of the shaft of the tail, by pipetting the cercariae onto the shaved abdominal skin of the anaesthetised animal. Two underdeveloped females were subsequently encountered in squash preparations of the liver when the hamster was killed for worm recovery 10 weeks after infection, thus showing that some of the abnormal cercariae were viable. A method is also described for killing and fixing cercariae while retaining some of the shining brilliance of live cercariae, without them becoming shrivelled, granular and semi-opaque, as occurs when cercariae die spontaneously or are killed with heat. This is apparently the first report of abnormal cercariae of S. mattheei. In addition, a method of concentrating abnormal cercariae after emergence from a snail, a schematic classification of abnormal cercariae and a method for killing and fixing cercariae while retaining much of the shiny brilliance of live cercariae are also reported for the first time as far as is known.  相似文献   

13.
李长胜 《家畜生态》1998,19(3):13-15
通过观察狐貂自咬症疾病行为特点,分析发病原因,传播途径,及时诊断治疗,以提高狐,貉养殖的经济效益。  相似文献   

14.
草地生态资产与生态系统服务概念与特征   总被引:1,自引:0,他引:1  
刘宥延 《草业科学》2022,39(4):795-805
随着?"两山"论和"山水林田湖草生命共同体"发展理念在我国草业领域的实践与应用,科学认识草地生态资产和生态系统服务的概念和内涵,对保证草地资产核算和生态系统服务价值评估的合理性和有效性具有重要意义.目前对草地自然资源、自然资产、生态资产和生态系统服务及价值的认识不尽相同,生态资产与生态系统服务价值的区别与关系混淆不清....  相似文献   

15.
Delmadinone acetate (DMA)? was tested by oral or parenteral administration to forty female and ten male dogs, and to twenty female and ten male cats for the control of heat and ovulation, and suppression of undesirable sexual and social behaviour. The indications, particulars of medication and the results obtained are shown in the table. The mode of action on the hypothalamus, pituitary and target organs is discussed. Over a thirty-six month trial period DMA proved to be a safe and efficacious drug for the control of sexual and related social functions in female and male pet animals. There were indications that even lower dosages than those employed may prove to be equally effective. Résumé. De l'acétate de delmadinone a été soumis à des tests, par administration buccale ou parentérale, sur quarante chiens femelles et dix chiens mâles et sur vingts chats femelles et dix chats mâles, pour le contrôle du rut et de l'ovulation et pour la suppression de comportement indésirable, sexuel et social. Les indications, les détails de médication et les résultats obtenus sont indiqués à la table. On discute du mode d'action sur Phypothalamus, l'hypophyse et les organes-cibles. Au cours d'une période d'essai de 36 mois, l'acétate de delmadinone s'est révelé une drogue éfficace, sans danger, pour le contrôle des fonctions sexuelles et sociales apparentées, chez les animaux familiers femelles et mâles. Il y avaient certaines indications, que même des doses plus faibles que celles utilisées peuvent se montrer également éffectives. Zusammenfassung. Delmadinonazetat (DMA) wurde durch orale oder parenterale Vera-breichung an vierzig weibliche und zehn männliche Hiade und an zwanzig weibliche und zehn männliche Katzen zur Kontrolle der Hitze und Ovulation, und Suppression von unerwünschtem sexuellem und sozialem Verhalten, gegeben. Die Indikationen, Eigenheiten von Medikation und die erlangten Ergebnisse sind in der Tabelle verzeichnet. Die Art der Wirkung auf den Hypo-thalamus, die Hypophyse und die Erfolgsorgane ist erört. Über eine 36 monatige Versuchsperiode, DMA bewies sich als ein sicheres und wirksames Medikament zur Kontrolle von sexuellen und verbundenen sozialen Funktionen in weiblichen und männlichen Haustieren. Es gab Anzeichen, dass selbst eine niedrigere Dosis als die angewand, sich ebenso wirksam erweisen mag.  相似文献   

16.
秦川牛因原产于陕西八百里秦川而得名,具有体躯高大、遗传稳定、适应性强、肉用性能好等特点,是我国著名的地方品种和国家级资源保护品种,是肉牛新品种培育和产业化发展的基础.文章介绍了秦川牛种质资源保护利用情况和取得的成效,并针对当前存在的问题提出了相应的对策和建议,以期对秦川牛种质资源的保护和开发提供科学指导,推动肉牛产业的健康发展.  相似文献   

17.
短毛黑水貂是我国人工饲养的主要水貂品种之一,为了解短毛黑水貂肌肉脂肪的组成成分、风味性成分,探讨其利用价值,分别利用气相色谱检测了水貂皮下脂肪中各种脂肪酸成分含量,利用氨基酸自动分析仪检测了背腰最长肌和股四头肌中各种氨基酸成分含量,利用气相色谱质谱分析法检测了肌肉中挥发性风味物质成分及其含量。结果显示短毛黑水貂皮下脂肪中不饱和脂肪酸占70%以上,必需脂肪酸亚油酸、亚麻酸含量可达25.76%;背腰最长肌和股四头肌中16种氨基酸含量分别为21.0%和18.4%;必需氨基酸分别占8.5%和6.8%,除甲硫氨酸外其他必需氨基酸的评分均接近或大于理想模式相应必需氨基酸的分值;肌肉中检测到23种挥发性风味成分,其中醇类、醛类、酮类三类化合物分别占8.63%,69.77%和3.44%;而呋喃类和烃酯类含量不到10%,这些对水貂肌肉脂肪胴体的特殊风味的形成具有重要作用。  相似文献   

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19.
被毛梳理是给宠物美容的主要部分,美容梳理后的犬猫,会变的更加美丽漂亮,人见人爱,给人们的日常生活增添乐趣。在给犬猫梳理前,要先检查它们的眼睛、耳朵、口腔、生殖道外口、肛门和爪子。长毛犬猫容易发生鼻泪管堵塞,此时它们的内眼角下面的被毛会变湿、变黄或变黑,主人可用棉花蘸着盐水擦洗一下,如果反复发生,要请兽医治疗。健康犬猫的耳朵内侧干净无臭味,如果外耳变脏,可用棉签蘸些滴耳液或植物油清除掉。如果犬猫经常用爪子抓搔耳朵,可能是耳内分泌物太多或病菌感染引起。若耳内分泌物过多,可向耳内滴入滴耳液或植物油,泡软后用棉签清除…  相似文献   

20.
概述了2013~2015 年顺昌县仁寿大丰收果蔬农民专业合作社在仁寿镇桥下村、长圳村、江墩村建立柑橘主要病虫专业化防治与绿色防控技术示范区情况。介绍了通过病虫专业合作组织开展以“冬季清园 捕食螨 生草栽培 修剪控梢 杀虫灯 科学用药(专业化统防统治)”的绿色防控技术,总结了其应用成效及存在问题和融合推进对策。  相似文献   

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