鸡传支对蛋鸡的危害及防治技术

(一)鸡传支的几种表现型鸡传支全称鸡传染性支气管炎,致病原为传染性支气管炎病毒,属于冠状病毒科、冠状病毒属的病毒。鸡传染性支气管炎在临床上表现型有肾型传支和腺胃型传支、呼吸型传支,还有鸡传染性支气管炎病毒变异毒株表现型,其临床症状有一定差异。鸡传染性支气管炎对蛋鸡的生长性能造成严重影响,在     

ND-IB二联灭活疫苗不同免疫方法对IB部分免疫效果影响的试验

鸡传染性支气管炎(IB)是由传染性支气管炎病毒(IBV)引起的鸡的一种急性、高度接触传染性病毒性疾病。鸡传染性支气管炎病毒属于冠状病毒科冠状病毒属,主要侵害鸡的呼吸系统、泌尿生殖系统等。鸡传染性支气管炎病毒作为鸡呼吸道疾病综合征的一种原发性病原,极易造成呼吸道疾病的继发感染,使疫情变得更加复杂,病死率升高,给养殖业造成严重的经济损失,不但会引起鸡只死亡,而且临     

FlockChek*鸡传染性支气管炎病毒抗体检测试剂盒在家禽疫苗监测中的应用

鸡传染性支气管炎病毒具有高度的传染性,通常出现在呼吸系统内,在小鸡群和防护较差的鸡群中能够造成很高的死亡率。对免疫系统状态的评价,以及对鸡传染性支气管炎病毒的血清学鉴定,需要有血清中鸡传染性支气管炎病毒抗体的测量数据。常规的免疫系统状态的检测可以应用红血球凝集抑制试验。FlockChek鸡传染性支气管炎病毒抗体检测试剂盒,为抗体的定量提供了一种灵敏而特异的方法。这一酶联免疫吸附试验试剂盒是专门设计用来确定商品禽群中鸡传染性支气管炎病毒的抗体水平。该检测可以在两个小时之内完成,大大节约了时间,可用于检测鸡传染性…     

鸡传染性支气管炎与传染性喉气管炎的诊治

1传染性支气管炎 鸡传染性支气管炎是由传染性支气管炎病毒引起的鸡高度传染性的急性呼吸道传染病,传染性支气管炎病毒属于冠状病毒科的冠状毒属。病鸡表现咳嗽、喷嚏,呼吸锣音,流鼻涕等呼吸道病症,或表现肾脏肿大,尿酸盐沉积等肾损害病症。     

鸡传染性支气管炎病毒抗体检测试剂盒在家禽疫苗监测中的应用

鸡传染性支气管炎病毒具有高度的传染性，通常出现在呼吸系统内，在小鸡群和防护较差的鸡群中能够造成很高的死亡率。对免疫系统状态的评价，以及对鸡传染性支气管炎病毒的血清学鉴定，需要有血清中鸡传染性支气管炎病毒抗体的测量数据。     

鸡传染性支气管管炎的综合防治措施

鸡传染性支气管炎是由传染性支气管炎病毒引起的鸡的一种急性、高度接触性呼吸道传染病。本文根据我县发生的案例，介绍了鸡传染性支气管炎的临床症状、病理变化、诊断和防治措施。     

治疗鸡传染性支气管炎的办法探讨

正鸡传染性支气管炎是一种传染性比较高的急性呼吸系统疾病,主要由传染性支气管炎病毒感染导致。虽然该病的死亡率较低,但患病后会导致蛋鸡或种鸡生长缓慢的同时产蛋率和蛋壳质量也会下降,从而使养鸡业的良性发展受到严重影响。那么,鸡传染性支气管炎如何治疗呢,下面进行详细介绍。1 鸡传染性支气管炎病原体鸡传染性支气管炎的病原体为传染性支气管炎病毒,其是一种单股负链RNA病毒,病毒颗粒有囊膜和球形,呈螺旋对称形状。该病毒对环境的适应能力较弱,不     

鸡肾型传染性支气管炎诊断与中西药防治

鸡传染性支气管炎是由传染性支气管炎病毒引起的鸡急性高度接触性传染的一种病毒性疾病。主要侵害鸡呼吸系统、泌尿生殖系统和消化系统，使病鸡出现呼吸困难、肾脏病变、输卵管病变及产蛋率下降等症状。鸡感染传染性支气管炎病毒后，通常使饲料报酬降低，产蛋下降或无产蛋高峰。近年来鸡肾型传染性支气管炎在我国各地流行，给养鸡业带来巨大的经济损失，严重危害养鸡业的健康快速发展。     

鸡传染性支气管炎的症状、诊断与防制

鸡传染性支气管炎是由冠状病毒科冠状病毒属的鸡传染性支气管炎病毒引起急性、高度接触性传染病。鸡传染性支气管炎病毒具有多血清型和多组织嗜性,主要有嗜呼吸道型、嗜肾型、嗜生殖器官型、嗜消化道型等。     

我国鸡传染性支气管炎流行现状及原因分析

禽的传染性支气管炎是严重危害世界养禽业的重要病毒性传染病。本文从鸡传染性支气管炎病毒、禽冠状病毒宿主范围以及我国鸡传染性支气管炎疫苗的使用和病毒分型等几个方面介绍并分析了该病在我国的流行现状。     

体细胞无性系变异及其在草坪草育种上的应用

综合国内外体细胞无性系变异的相关研究,概述了体细胞无性系变异产生方法、变异机制以及变异频率,详细地介绍了体细胞无性系变异在选育抗病虫害、逆境胁迫以及具优良农艺性状草坪草品种上的应用,讨论了应用体细胞无性系变异育种存在的问题及前景。     

Variability in respiratory function of the domestic fowl

Several respiratory parameters were measured in five groups of hens to estimate the variation in respiratory function of the general hen population. A non-invasive technique was used to measure respiratory flow, with computer-aided analysis of the data, and the results were examined statistically. Using different groups of hens, additional information was obtained regarding possible sources of variation between individual hens, such as egg laying condition, age and health. Significant differences between individuals within the groups were observed, but there were also changes in breath-to-breath variation for individual hens. While some changes in the variation between birds were observed from one group to another, variation within individual birds made interpretation of the results difficult. Repeated measurements made on one group revealed significant changes in minute volume with time, but the changes were not related to learning. Significant interactions between hens and time of measurement occurred for certain parameters, showing that the individuals' responses changed with time in different ways. The groups of hens were compared to observe whether they represented the same or distinct populations, and were found to overlap to varying extents for different respiratory parameters. Single respiratory variables and weighted combinations of certain variables were also used to separate the groupings, as a possible diagnostic method for partitioning groups of hens.     

广东南岭国家级自然保护区蝶类季节变化的研究初报

2004年4月～2005年5月，对广东南岭国家级自然保护区蝶类进行了种类、数量调查统计，分析了该地区蝶类资源的季节性变化。共收集蝴蝶标本1682余只，隶属7科30属30种。研究表明蝴蝶及活动情况随着不同季节的变化、植被类型及植物生长情况的变化是决定蝴蝶种类组成和分布的主要因素，人为活动也是影响种群消长的因素之一。     

Variation in free water intake in lactating ewes

The aim of this study was to investigate individual free water intake (FWI) in lactating ewes, with two suckling lambs. Eighteen ewes were housed in single experimental pens from the time of lambing to two weeks after lambing. The ewes had free access to water from a drinking bowl and water meters were used to record the daily FWI. On average, the FWI for the ewes was 14.42?l/day. The variation between individuals was large (CV 27.6%) and varied between 8.16 and 21.88?l/day. It was also large variation within individuals (CV 19.2%). Hay DM intake were the factor that affected the FWI the most. Due to the large variation between and within ewes, FWI are not a stable individual characteristic. This study is useful for farmers to understand water supply needed for lactating ewes.     

Precision-controlled echocardiographic left ventricular function parameters by repeated measurement on three consecutive days in trained and untrained warmblood horses

Echocardiographic measurements have to be reliable and reproducible with only a low day to day variability for detecting pathological changes of left ventricular myocardial function in horses. The day dependent fluctuation margin represents an important indicator for the reproducibility of a method. To find out the day to day variability of echocardiographic parameter in healthy warmblood horses, in the present study repeated echocardiographic measurements at three consecutive days were carried out (at the same time and by the same examiner) at 11 untrained and 7 trained warmblood horses. The horses were examined from the right hemithorax, in five different B- and M-Mode views in the long and short heart axis. The echocardiographic measurements in the three-day examination interval showed with coefficient of variation between 3.4 and 25.8% a good reproducibility. In order to calculate the precision of echocardiographic parameters (reproducibility from day to day) statistical analysis was carried out by means of a linear model with random effects. Herefor the variation between repeated measurements over three days and within the horses (day to day intraindividual variation) as well as the variation between the horses (interindividual variation) were taken into account. In dependency of the echocardiographic parameters 46.2-95.7% (median 85.7%) of the variation is caused by the difference between the horses (intraclass correlation) and 4.3-53.8% (median 14.3%) of the variation is caused by the repeated measurements on different days. With a coefficient of variance from 6.6% and an intraclass correlation of 0.957 the left ventricular diastolic diameter at the level of the papillary muscles showed the lowest variation between repeated measurements on different days. The heart rate with a coefficient of variance of 10.3% and an intraclass correlation of 0.462 showed the highest variation with 53.8% between the repeated measurements on different days. The precision of single echocardiographic measurements is confirmed. All parameters were also tested for differences between trained and untrained horses. Significant differences (p<0.05) could be found in the left ventricular diameter at the level of the apex cordis and under the mitral valves as well as in the systolic left ventricular area.     

Comparison of strains of Mycoplasma iowae

Comparison of biochemical test results and protein electrophoretic patterns of 21 strains of Mycoplasma iowae indicated that all were similar. Comparison of agglutination test results indicated marked within-species antigenic variation. None of 21 antigens prepared from different strains were effective in demonstrating turkey antibody against five reference strains. Examination of sera from turkeys exposed by intra-air-sac inoculation to two pathogenic strains also indicated antigenic variation. Neither the M. iowae type-strain, Iowa 695, nor the other reference strains were effective in demonstrating antibody against both strains used to expose the turkeys. These findings suggest that antigenic variation may be a major problem in effective serodiagnosis of M. iowae infections.     

巴彦淖尔市干旱指数变化规律和草原退化原因

采用巴彦淖尔市4个牧业旗县气象站40a（30a）的关键时段平均气温和降水量资料，计算逐年干旱指数，由各站干旱指数来评定草原旱涝程度，并依此评判逐年牧草长势，分析其变化规律.结果表明，随着气候逐渐变暖，干旱指数呈增大趋势，即草原干旱呈加重趋势。气候干旱是引起草原沙化的主要因素之一，据此提出了防止草原退化的建议。     

Prioritization based on neutral genetic diversity may fail to conserve important characteristics in cattle breeds

Conservation of the intraspecific genetic diversity of livestock species requires protocols that assess between-breed genetic variability and also take into account differences among individuals within breeds. Here, we focus on variation between breeds. Conservation of neutral genetic variation has been seen as promoting, through linkage processes, the retention of useful and potentially useful variation. Using public information on beef cattle breeds, with a total of 165 data sets each relating to a breed comparison of a performance variable, we have tested this paradigm by calculating the correlations between pairwise breed differences in performance and pairwise genetic distances deduced from biochemical and immunological polymorphisms, microsatellites and single-nucleotide polymorphisms. As already observed in floral and faunal biodiversity, significant positive correlations (n=54) were found, but many correlations were non-significant (n=100) or significantly negative (n=11). This implies that maximizing conserved neutral genetic variation with current techniques may conserve breed-level genetic variation in some traits but not in others and supports the view that genetic distance measurements based on neutral genetic variation are not sufficient as a determinant of conservation priority among breeds.     

哈萨克羊、阿勒泰羊、巴什拜羊遗传多样性的AFLP分析

利用11对AFLP引物组合,检测了哈萨克羊、阿勒泰羊、巴什拜羊池DNA遗传变异,构建了各品种的AFLP DNA 指纹图谱,根据AFLP分析结果,统计了每个引物组合在各品种中检测到的多态性条带,计算了3个品种的遗传相似系数,并据此构建了UPGMA聚类关系图,分析了它们的遗传关系.结果表明:11对AFLP引物组合在3个地方绵羊品种中共检测到310条带,平均每个引物组合产生28.18条带,变化范围在25～34条,其中多态性条带32条,占扩增总带教的10.32%,每对引物平均扩增多态性带2.909条.品种间的遗传相似系数以哈萨克绵羊与阿勒泰绵羊的最高(O.699),哈萨克绵羊与巴什拜绵羊最小(0.592),聚类结果与这些羊的育成史、分化及地理分布一致.