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1.
Q fever is zoonotic disease caused by Coxiella burnetii. Ruminants are the main reservoir of this pathogen, which is often asymptomatic but lead to abortion. This study aims to survey the seroprevalence and risk factors of this zoonose among ruminants in Kurdistan province, the west of Iran. 480 blood samples were collected from ruminants including sheep, goats and cows, each 160 samples, in the age groups of <1, ≥1−3, >3−5 year with and without the history of abortion in two groups border and non-border cities in Kurdistan province. Serums were tested by use of indirect ELISA to determine specific antibodies against C. burnetii. The results indicate the seroprevalence of 46.6 % for Q fever. Seroprevalence in sheep, goats and cows were 28.58 % (n = 64), 45.53 % (n = 102) and 25.89 % (n = 58), respectively. Seroprevalence is significantly higher in animals with abortion than in those without such history (P < 0.05). The seroprevalence in the border cities has been significantly higher than other geographical areas (P < 0.05). Seroprevalence had no significant correlation with animal age (P> 0.05). This study is the first seroepidemiological study done on Q fever in ruminants of Kurdistan province, Iran. The results indicate the high seroprevalence of Coxiella burnetii in the area under the study. Therefore, doing an epidemiologically study aimed at isolating C. brunetii in the human population of Kurdistan province is recommended, so that the epidemiological aspect of this pathogen in the people of Kurdistan province be clarified and subsequently disease control and prevention programs be applied.  相似文献   
2.
张文通  魏凤  李峰  沈志强 《猪业科学》2020,37(7):100-101
文章介绍了5种商品化猪丹毒疫苗的种类、毒株组成、抗原含量及相应免疫程序,为了解各种类型的猪丹毒商品化疫苗提供参考。  相似文献   
3.
非洲猪瘟对中国生猪市场和产业发展影响分析   总被引:4,自引:1,他引:3  
受非洲猪瘟疫情、环保等因素影响,生猪产能快速深度下降,未来2 a猪肉供给偏紧特征明显,生猪价格快速进入新一轮上涨周期,未来养殖收益将连续3 a处于较好水平,未来2 a猪肉进口预期创新高。短期来看,非洲猪瘟影响下产销区供给过剩和供给偏紧交替出现,猪价由区域分化演变为普遍性上涨。受非洲猪瘟防控政策、产业生物安全水平提升需求和近期出台的产业支持政策等因素影响,中国生猪产业的生产和屠宰布局、流通模式、消费结构、猪肉贸易、价格周期等发生深刻变革。非洲猪瘟导致中国生猪养殖模式向适度规模转变,"公司+农户"成为主要发展模式,屠宰产能由销区向产区转移,管理和防疫成本提高,生猪产能恢复速度将较缓慢,猪肉消费加速向冷鲜肉转变,在肉类消费结构中比重将进一步下降,未来猪肉进口保持较高水平将成为常态。要有效实施非洲猪瘟分区防控、保障生猪市场稳定,需要通过加强区域化防控机制的顶层设计和立法,优化非洲猪瘟强制性扑杀补贴机制,加强基层兽医体系建设,实施"政府+企业+养殖户"联防联控,降低疫病传播风险,推动生猪产业可持续发展。  相似文献   
4.
旨在了解河南省猪流感病毒的流行情况及其遗传进化和基因组特征。2018年4月,从河南省某一出现疑似流感症状猪群中采集鼻拭子样品150份用于分离病毒,对分离病毒的全基因组进行序列测定和分析。同时感染6周龄BALB/c小鼠,研究其对小鼠的致病性。结果显示,获得1株H1N1亚型病毒[命名为A/swine/Henan/NY20/2018(H1N1)]。遗传进化表明,其HANA基因属于欧亚类禽H1N1分支,PB2、PB1、PANPM基因属于2009甲型H1N1分支,NS基因属于经典H1N1分支。HA蛋白的裂解位点序列为PSIQSR↓GL,具有低致病性流感病毒的分子特征,在小鼠肺和鼻甲有效复制并能引起肺组织病理学变化。本研究分离到1株3源重排H1N1亚型病毒,对小鼠呈现一定致病力,提示应进一步加强对SIV的监测。  相似文献   
5.
Fishmeal (FM) is a high-cost and scarce feedstuff. Notwithstanding, the formulation and processing of diets for carnivorous fish strongly rely on FM as a protein source, given its palatability and biological value. Animal by-product hydrolysates are high-quality feedstuff and can substitute FM in aquafeeds. This study evaluated the digestibility of hydrolysates from tilapia residue (TR), tuna head (TH), swine liver (SL), and poultry liver (PL), and the profile of digestive enzymes in juvenile dourado, Salminus brasiliensis, a carnivorous Characin, fed diets containing graded levels of the hydrolysates. Inclusion of hydrolysates in diet formulations lowered the pH of feed but did not alter feed intake by fish. Higher apparent digestibility coefficients (ADCs) of diets were recorded for fish fed diets containing TR and SL, and lower ADCs were recorded for fish fed diets containing TH. Protease and lipase activities in the animal’s stomach were higher, especially for those fed with diets containing SL. Amylase activity was higher in pyloric caeca, whereas in the intestines, the higher activity was seen in fish fed control and TR diets. Animal by-product hydrolysates were highly digestible for dourado, and the enzymatic profile of fish was influenced by the nutrient contents of diets.  相似文献   
6.
生猪养殖设施工程技术研究现状与发展分析   总被引:7,自引:0,他引:7  
生猪养殖业是我国畜牧业的支柱产业,随着生猪养殖从分散养殖向规模化养殖的发展,对生猪养殖设施工程技术的需求日渐增加。为了向生猪养殖业发展提供参考与支持,对生猪养殖关键设施工程技术的研究与发展状况进行了总结和分析。重点对猪舍、育仔、饲喂、粪污处理设施工程环节进行研究与发展分析。目前,我国已初步形成了适合国情的生猪养殖设施工程技术体系,但与国外发达国家的生猪养殖设施工程技术还存在一定差距,存在养殖设施工程各环节发展不均衡,养殖工程的机械化、自动化、智能化技术水平较低,关键养殖设施工程技术的基础性研究体系不健全,养殖设施配套性差,养殖机械的适用性和可靠性较低等问题。建立健全的生猪养殖设施工程技术的研究体系,加强养殖、饲料、设施工程、资源环境等方面相互融合与协作、深入与系统的研究,开展适于我国南北方配套应用的生猪养殖设施与设备研发,实现生猪养殖过程的健康/福利化、生态化、自动化及至智慧化,将是我国生猪养殖设施工程技术的发展方向。  相似文献   
7.
Elephant ovaries contain multiple corpora lutea (CLs) throughout pregnancy. Two CLs (P‐1 and P‐2) collected from a pregnant African elephant were used to investigate their origin and physiological state in this study. The mRNA expressions of prolactin receptor, CYP11A and inhibin betaB subunit were higher in P‐2 than in P‐1, while LHCGR and inhibin betaA subunit mRNA were higher in P‐1 than in P‐2. Protein expression of cleaved caspase‐3 was detected in P‐1 but not in P‐2. These results suggest different origins for the two CLs in this one pregnant elephant, and we also demonstrated the production of bioactive prolactin by the elephant placenta.  相似文献   
8.
Twelve lactating sows were used to evaluate the effects of reducing dietary crude protein (CP) (14% vs. 12%) and increasing neutral detergent fibre (NDF) levels (18% vs. 22%) on litter performance, total tract apparent digestibility and manure composition in a 4 × 4 latin square arrangement during a 36‐day lactation period. Diets were isoenergetic (2.9 Mcal ME/kg) and had similar total lysine content (0.9%). In addition, a second aim was to compare a reference external marker method (Cr2O3) with an internal feed marker [acid‐insoluble ash (AIA)] for the calculation of apparent total tract digestibility of nutrients in lactating sows. The reduction of dietary CP level in lactating sows had no effect on either live‐weight or backfat thickness or apparent total tract digestibility of nutrients. However, the piglets' average daily gain (ADG) was reduced in low dietary CP diets, which suggests that sows reduced milk production due to an underestimation of certain essential amino acid requirements (e.g. valine). The increase of dietary NDF level did not affect sow and litter performance. Nevertheless, the total tract apparent digestibility of organic matter, CP and carbohydrates was reduced, and ether extract digestion was increased in high NDF compared to normal NDF diets equally balanced for ME and lysine content. The coefficients of total tract apparent digestibility of nutrients in lactating sows were greater when using AIA compared to Cr2O3 marker, regardless of dietary CP or NDF level, but their coefficients of variation were lower in the former than in the latter. In lactating sows, a trade‐off between litter performance and nutrient digestion is established when reducing dietary CP or increasing NDF levels while maintaining similar lysine content through synthetic amino acids and balancing metabolizable energy through dietary fat sources.  相似文献   
9.
许浒  潘研  宋铭忻 《中国畜牧兽医》2020,47(8):2561-2570
为了解中国猪瘟病毒(classical swine fever virus,CSFV)的分子流行病学及遗传变异情况,本研究应用RT-PCR方法对2018年采集自河南、河北、山东、黑龙江和辽宁5个省份的350份疑似CSFV感染的病料进行E2和NS5B基因扩增,并对PCR产物进行测序和序列分析。结果显示,350份样品中21份为CSFV阳性,共获得14株CSFV的E2基因序列和7株CSFV的部分NS5B基因序列。E2全基因、NS5B部分基因序列分析表明,21份阳性样品均属于近年来在中国流行的CSFV 2.1d亚型,且新发现的2.1d亚型CSFV与中国较早2.1d亚型CSFV毒株间同源性差异不大,新发现的2.1d亚型CSFV分离株在E2基因的6个氨基酸(R31、S34、W182、K205、K303、A331)上具有相同的分子特征,E2蛋白中15个位点上的半胱氨酸均未发生变异。韩国2.1d亚型CSFV在E2蛋白上具有3个独特的氨基酸(N97、K159、R205)特征,并且发现了韩国毒株YC11WB可能作为2.1b和2.1d亚型CSFV过渡毒株的证据,流行于中国和韩国的2.1d亚型CSFV可能分别来自于本国早期2.1b亚型CSFV的衍化。本研究证实,2018年中国及周边国家CSFV较为活跃,且流行毒株依然以2.1d亚型为主,为中国科学防控CSFV提供了依据。  相似文献   
10.
国医大师熊继柏教授临床上善于诊治各种疑难杂症,本文列举熊老师运用宣痹汤复方治疗疑难病案例:反复发热案、淋巴瘤发热案、类风湿性关节炎案、发热皮疹案、肺部占位并全身结节案5则,其病机均属湿热痹阻经脉,通过对上述异病同治案例的分析,以示熊继柏教授的辨证思路,并为临床上应用宣痹汤提供参考。  相似文献   
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