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82.
为了解湖南省长沙市布鲁氏菌病流行现状,对奶羊养殖场(户)和种羊场采用普查策略,对其他羊养殖场(户)采用两阶抽样策略,选择羊群并选定群体中个体,采集血样进行布鲁氏菌抗体检测。同时,通过问卷调查和查阅资料等方式,分析布鲁氏菌病感染和传播风险。结果显示:全市羊布鲁氏菌病表观场群流行率为1.54%(95%CI:0.42%~3.91%),表观个体流行率为0.60%(95%CI:0.43%~0.80%);4个阳性群集中分布于长沙县和宁乡县;和以往监测数据相比,长沙市的羊群布鲁氏菌病流行率和人间发病率均呈下降趋势,说明前期的防治策略取得积极成效。总体来说,长沙市布鲁氏菌病流行率较低,疫情处于稳定控制状态,因而可以分区域逐步实现全市布鲁氏菌病净化。 相似文献
83.
放牧对武功山草甸土壤微生物生物量及酶活性的影响 总被引:2,自引:0,他引:2
以武功山山地草甸为研究对象,通过分析不同放牧强度对土壤微生物生物量碳氮以及酶活性的影响,旨在为退化草甸修复提供理论依据。结果表明:1)不同土壤微生物生物量碳氮含量表现为0-20cm土层20-40cm土层,除20-40cm土层轻牧和中牧的土壤微生物生物量氮无显著差异外(P0.05),随放牧强度增加,土壤微生物生物量碳氮含量均显著降低(P0.05);2)可溶性碳氮含量在0-20和20-40cm土层间无显著差异(P0.05),均表现为在0-20cm土层轻牧显著大于中牧和重牧(P0.05);3)碱解氮和易氧化碳含量表现为在不同土层,轻牧和中牧含量均显著高于重牧(P0.05);4)土壤β-葡萄糖甘酶、β-N-乙酰氨基葡萄糖甘酶和脲酶活性表现为在不同土层下,轻度和中牧均显著高于重牧(P0.05);5)相关性分析表明,不同放牧强度土壤β-葡萄糖甘酶、β-N-乙酰氨基葡萄糖甘酶和脲酶活性与微生物生物量碳氮均呈显著性正相关(P0.05)或极显著正相关(P0.01)。 相似文献
84.
1990~1997年间,本研究室从广西不同地区鸡场死于禽巴氏杆病菌的家禽中分离并鉴定13株禽巴氏杆菌(包括鸡源的12株,鸭源的1株)。菌株经中国兽药监察所进行Carter定型,结果为荚膜A型。13个分离菌株都100%致死本地三黄鸡。 相似文献
85.
Abattoir survey was conducted on 1,053 sheep and 639 goats slaughtered at Addis Ababa Abattoir, Ethiopia, between October
2007 and May 2008, with the objective to determine the prevalence of hydatidosis and assess the associated risk factors. Routine
meat inspection procedure was employed to detect the presence of the cyst in visceral organs (lung, liver, and omentum). Hydatid
cysts were found in 206 (19.94%) and 102 (16%) of the sheep and goats inspected, respectively. Statistically significant difference
in infection rates was noted between the two species. Likewise, there was significant difference in infection rates between
the two sexes and different age groups in both sheep and goats (P < 0.5). The study showed that hydatidosis is prevalent in Ethiopia. Thus, there is a need to introduce appropriate control
measures to minimize the rate of infection and reduce the ensuing economic losses. 相似文献
86.
Partitioning the respiratory components of soil surface CO2 efflux is important in understanding carbon turnover and in identifying the soil carbon sink/source function in response to land-use change. The sensitivities of soil respiration components on changing climate patterns are currently not fully understood. We used trench and isotopic methods to separate total soil respiration into autotrophic (R A ) and heterotrophic components (R H ). This study was undertaken on a Robinia pseudoacacia L. plantation in the southern Taihang Mountains, China. The fractionation of soil 13CO2 was analyzed by comparing the δ13C of soil CO2 extracted from buried steel tubes with results from Gas Vapor Probe Kits at a depth of 50 cm at the preliminary test (2.03‰). The results showed that the contribution of autotrophic respiration (fR A ) increased with increasing soil depth. The contribution of heterotrophic respiration (fR H ) declined with increasing soil depth. The contribution of autotrophic respiration was similar whether estimated by the trench method (fR A , 23.50%) or by the isotopic method in which a difference in value of 13C between soil and plant prevailed in the natural state (RC, 21.03%). The experimental error produced by the trench method was insignificant as compared with that produced by the isotopic method, providing a technical basis for further investigations. 相似文献
87.
本研究通过细胞融合、间接ELISA方法筛选出4株可稳定分泌犬瘟热病毒(canine distemper virus,CDV)和犬细小病毒(canine parvovirus,CPV)单克隆抗体的杂交瘤细胞株,以此为基础研制了一种可同时检测CDV和CPV的胶体金二联检测卡,并对其特异性、灵敏度及准确性进行了测试。结果显示:4株杂交瘤细胞可稳定传代,分泌的单克隆抗体纯度高,效价均在1:320以上。制备的胶体金二联检测卡特异性强,只与CDV和CPV产生特异性条带,而不与其他犬类病毒反应;灵敏度高,最低检测限可达到102拷贝/μL;准确性好,与荧光定量PCR结果的符合率高于88.0%,与市面上单一病毒检测卡的符合率高于97.2%。结果表明,本研究制备的CDV、CPV胶体金二联检测卡特异性强、灵敏度高、准确性好,兼具操作简便、肉眼可判读、结果易保存和无需特殊仪器设备等优势,可用于两种疾病的临床快速诊断和大规模检测工作。 相似文献
88.
Aklilu HA Almekinders CJ Udo HM Van der Zijpp AJ 《Tropical animal health and production》2007,39(3):165-177
This study aimed to examine village poultry consumption and marketing in Ethiopia in relation to gender, socio-cultural events
and market access. The main objects of the research were producers, poultry markets, producer-sellers, and intermediary sellers
in three locations representing different levels of market access in Tigray. About 3000 farm records were collected over a
period of 12 months from 131 producers to obtain quantitative data on sales and consumption. Ninety-three semi-structured
interviews with 58 producer-sellers and 35 intermediaries and 12 group discussions with these market actors were conducted
to explore organization, price dynamics and socio-cultural aspects of poultry marketing. In total, 928 producer-sellers and
225 intermediaries were monitored monthly to examine participation by gender in poultry marketing. Better market access was
associated with a shorter market chain and higher prices for the producers. Female-headed households had smaller poultry sales
and consumption per household but sale and consumption per family member were 25% and 66% higher, respectively, than in male-headed
households. While women dominated in the producer-sellers group, intermediaries were mainly men. Religious festivals periodically
shifted local demand and prices of poultry. To improve the benefit of poultry keeping, poverty-stricken households may profit
from better market access through better market information, infrastructure, market group formation and careful planning to
match the dynamics in demand. 相似文献
89.
试验选择母猪胎次、初生体重相近的杜长大三元杂交哺乳仔猪24窝,随机分为对照组,试验Ⅰ、Ⅱ组,每组八窝。对照组饲喂常规乳猪料,试验Ⅰ、Ⅱ组分别饲喂添加10%、20%发酵豆粕的乳猪料,研究发酵豆粕对仔猪生长性能的影响。结果表明试验Ⅰ、Ⅱ组仔猪平均日增重、平均日采食量均显著高于对照组(P<0.05),而料肉比、腹泻率显著低于对照组(P<0.05);试验组Ⅱ平均日增重、平均日采食量高于试验组Ⅰ,料肉比、腹泻率低于试验组Ⅰ,但二者之间差异不显著(P>0.05)。 相似文献
90.
鄱阳湖区血吸虫病流行病学调查与疫情分析 总被引:1,自引:0,他引:1
为了调查湖区血吸虫病流行环境与传染源构比,找出主要传染源、传播途径和场所,进一步揭示流行规律,为制定血防对策提供依据.调查范围为鄱阳县及两乡四村.结果,草洲钉螺占99.4%,90%以上牛上洲放牧,人粪流放率31%,其中渔民78%,牛粪流放率78%,其中64%直接污染草洲水体,野粪构比中牛占92.8%,传播粪量牛占98.85%,人占0.96%,其中渔民占0.12%.结论认为湖区疫情重,主要传染源是牛,主要感染途径是接触疫水,疫水形成的主因是牛上洲放牧,主要感染场所是草洲及周边水体.增加血防投入,稳定队伍,实施查治病和"四个突破"为主体的防治策略,控制畜源性传染源,净化环境与草洲,切断传播途径,才能有效控制血吸虫病. 相似文献