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11.
为研究突触融合蛋白17(STX17)基因与蒙古马毛色之间的相关性及其作用机制.本研究利用半巢式PCR技术及实时荧光定量PCR技术对蒙古马STX17基因第6内含子的多态性以及不同毛色蒙古马皮肤组织中STX17基因的相对表达量进行了检测.巢式PCR结果显示:STX17基因在青毛蒙古马第6内含子处存在4.6 kb的重复片段,在其它毛色中不存在该重复片段;荧光定量PCR结果显示:STX17基因在蒙古马青毛皮肤组织中表达量最高,在骝毛皮肤组织中的表达量最低.结果证明蒙古马STX17基因与其青毛表型具有典型的相关性.  相似文献   
12.
脱氧雪腐镰刀菌烯醇(deoxynivalenol, DON)是一种常见的污染粮食、饲料和食品的霉菌毒素,严重影响人和牲畜的健康。猪对DON非常敏感,DON可造成猪拒食、生长抑制、呕吐以及器官损伤、细胞毒性、免疫毒性等毒害作用。本文主要综述了DON对猪的毒害作用、毒理机制以及解毒剂开发等方面的研究进展,尤其关注DON毒理作用的遗传调控研究,旨在为从遗传本质提高猪对脱氧雪腐镰刀菌烯醇的抵抗力提供更全面的参考。  相似文献   
13.
Lai H  Zhang H  Ning Z  Chen R  Zhang W  Qing A  Xin C  Yu K  Cao W  Liao M 《Veterinary microbiology》2011,151(3-4):275-283
Subgroup J avian leukosis virus (ALV-J), first isolated in 1989, predominantly causes myeloid leukosis (ML) in meat-type or egg-type chicken. Since 2006, the clinical cases of hemangioma rather than ML in commercial layer flocks associated with ALV-J have been reported, but it was still not clear whether the novel oncogenic ALV-J had emerged. We characterized SCAU-HN06 isolate of ALV-J from hemangioma in commercial Roman layers through animal experiment and full-length proviral genome sequence analysis. The SPF white leghorn egg-type chickens infected with SCAU-HN06 in ovo at day 11 of incubation showed an overall incidence of 56% hemangioma and 8% renal tumor throughout the 22-week trial, the mortality rate was 16%. Most genes of SCAU-HN06 isolate showed high nucleotide sequence identity to JS09GY6 which was isolated from Hy-Line Variety Brown layers suffering hemangioma. The 19-bp insertion in leader sequence and one key deletion in E element were the common features of SCAU-HN06 and JS09GY6. SCAU-HN06 and those ALV-Js associated with hemangioma, possibly recombinants of ALV-J and other avian retrovirus, may share the same ancestor.  相似文献   
14.
Since 1993, 14 cases of avian influenza from four different states in the U.S.A. have been diagnosed by virus isolation from eight avian species. Only 11 of the 14 avian influenza virus (AIV) primary isolations would have been successful if only the standard protocol for AIV isolation, i.e., inoculation of specific-pathogen-free embryonating chicken eggs (ECEs) by the chorioallantoic sac (CAS) route, had been followed. Primary isolation attempts were negative for AIV in three cases in which ECEs were inoculated by the CAS route; AIV could not be detected by hemagglutinating activity, agar gel immunodiffusion test or negative stain electron microscopy. However, in these three cases, primary isolations of AIV were achieved by inoculation of ECEs into either the yolk sac or onto the chorioallantoic membrane.  相似文献   
15.
Three experiments were conducted to investigate the effects of beta-glucan supplementation on pig performance and immune function. In Exp. 1, 100 weaned pigs (8.65 +/- 0.42 kg of BW and 28 +/- 2 d of age) were used in a 35-d experiment to determine the effects of graded levels of beta-glucan. Pigs were randomly allotted to 1 of 5 treatments containing beta-glucan supplemented at 0, 25, 50, 100, or 200 ppm. Each treatment was replicated using 5 pens containing 4 pigs per pen. The ADG of pigs between d 14 to 28 and d 0 to 28 responded to dietary beta-glucan in a quadratic fashion (P < 0.05), whereas beta-glucan had no effect on ADFI and G:F in any period. In Exp. 2, 80 crossbred pigs (8.23 +/- 0.56 kg of BW and 28 +/- 2 d of age) were used in a 35-d experiment. Pigs were allotted to 1 of 2 dietary treatments (0 or 50 ppm of beta-glucan in the diet) using 10 pens with 4 pigs per pen. Pigs treated with beta-glucan had greater ADG in the 14- to 28-d (P = 0.05) and 0-to 28-d (P = 0.035) periods. The ADFI of pigs receiving beta-glucan was increased (P < 0.05) in the periods from 0 to 14, 0 to 28, and 28 to 35 d. The lymphocyte proliferation index in response to phytohemagglutinin (P = 0.051) and concanavalin A (P = 0.052) tended to decrease on d 14 in pigs supplemented with beta-glucan compared with pigs without supplementation. In Exp. 3, 24 barrows (8.89 +/- 0.20 kg of BW and 28 d of age) were used to investigate the immunological and somatotropic responses of pigs challenged with lipopolysaccharide (LPS). Experimental treatments were arranged in a 2 x 2 factorial, with the main effects of LPS challenge (saline vs. LPS) and dietary addition of beta-glucan (0 vs. 50 ppm). Pigs were raised individually in metabolic cages. Pigs were fed 0 or 50 ppm of beta-glucan for 28 d and then challenged with LPS (25 microg/kg of BW) or saline. After LPS injection, blood was obtained at 0, 1.5, 3, 4.5, 6, and 7.5 h to determine cytokine production and the somatotropic response. Dietary beta-glucan increased plasma interleukin-6 at 1.5, 3, and 4.5 h and tumor necrosis factor-alpha at 3 and 4.5 h and increased plasma interleukin-10 from 3 to 7.5 h after LPS challenge. The beta-glucan treatments had no effect on growth hormone. In conclusion, beta-glucan can selectively influence performance and partially offer benefits on somatotropic axis and immune function in weaned piglets challenged with LPS.  相似文献   
16.
Q fever (QF) is a worldwide zoonosis associated with outbreaks. Only a few nationwide studies regarding the surveillance and epidemiology of human QF have been reported. Although QF is endemic in Taiwan, a nationwide database investigation of the epidemiology and characteristics of QF and its associations with scrub typhus (ST), murine typhus (MT) and leptospirosis (LS) has never been reported. We analysed nationwide databases of suspected QF, ST, MT and LS cases from October 2007 to December 2014 obtained from the Centers for Disease Control, Taiwan. A total of 468 (4.2%) QF cases were identified among 11 109 suspected QF cases. QF cases were mainly distributed in the southern and Kaohsiung–Pingtung regions but rarely in the eastern region. Compared to non‐QF cases, QF cases had significantly higher percentages of males (88.7 versus 66.2%) and high‐risk occupations (farming, animal husbandry or veterinary medicine) (16.2 versus 10.5%). But the percentages of specific animal contact, including cattle (0.6 versus 0.8%) and goats (0.9 versus 1.0%), were low in both. The majority of suspected QF cases (89.4%) were simultaneously suspected with ST, MT or LS, and the combinations of suspected diseases differed between regions. The number of suspected QF cases from the eastern region decreased since 2009, which was not observed in other regions. A total of 1420 (12.8%) cases had confirmed diseases, including QF (453, 4.1%), QF+ST (7, 0.06%), QF+MT (4, 0.04%), QF+LS (4, 0.04%), MT (186, 1.7%), ST (545, 4.9%), ST+LS (11, 0.1%) and LS (210, 1.9%). Compared to cases of unknown disease, QF cases had larger percentages of high‐risk occupations (16.2 versus 9.6%) but similar histories of animal contact (29.8 versus 25.1%). QF is an endemic disease in southern Taiwan. It is difficult to differentiate QF from ST, MT or LS only by high‐risk occupations and history of animal contact, and co‐infection of QF with these diseases should be considered.  相似文献   
17.
绵羊在发情周期中各生殖激素浓度变化与卵泡发育、成熟和排卵有着密切的关系。为了研究巴美肉羊血清生殖激素的动态变化及其与排卵数关系,试验采用电化学法,测定了12只成年母羊发情期血清中2种类固醇激素(E2和P4)的浓度水平,分析其动态变化规律,并用SAS 9.0的方差分析程序分析激素浓度与排卵数的关系。结果表明,两种激素在排单卵组和排双卵组绵羊间变化规律不同,E2在排单卵组表现为先下降后升高的变化趋势,在排双卵组表现为持续下降趋势;P4在排单卵组表现为持续上升的趋势,在排双卵组为先上升后下降的变化趋势。排单卵和排双卵组绵羊在各时间点的E2和P4激素浓度差异均不显著(P>0.05)。  相似文献   
18.
From 2007 to 2009, the prevalence of intestinal parasites was investigated in intensive and extensive pig farms in Chongqing, China. A total of 2971 samples from both sexes and five age categories (breeding boars, breeding sows, fatteners, growers and weaners) were evaluated by standard methods for the presence of helminth ova and protozoan oocysts, cysts and/or trophozoites. Of the 2971 pigs sampled, 362(12.18%) were infected with Ascaris suum, 301(10.13%) with Trichuris suis, 301(10.13%) with Oesophagostomum spp., 491(16.53%) with Eimeria spp., 149(5.02%) with Isopora suis, 677(22.79%) with Balantidium coli and 196(6.60%) with Cryptosporidium spp. Growers had the highest infection rate while breeding boars had the lowest among the five age categories. B. coli was the most common protozoan in all pig age groups. Pigs infected with multiple parasites were common. Risk factors such as management methods, seasons, ages, etc. can influence the infection rate to a certain degree. This investigation provides relevant data about risk factors for pig farmers, thus allowing them to make more appropriate antiparasitic treatments according to farm conditions and local climate in Chongqing.  相似文献   
19.
初乳是奶牛产后24 h内的乳汁,为犊牛提供天然免疫和早期生长的能量来源,且初乳在医疗保健领域也具有一定的研究价值。初乳在产后一段时间内的物质成分会发生较大的变化,与常乳形成明显的差异。本文对比分析了初乳和常乳中营养物质、免疫活性物质、生长因子以及酶的含量差异,直观地展现了初乳中不同物质的变化过程,针对性地为初乳和常乳的加工制作提供思路,为特异性地开发初乳资源,提升初乳的利用率给出参考依据。  相似文献   
20.
乙脑病毒PrME基因在杆状病毒表达系统中的表达   总被引:2,自引:0,他引:2  
本试验将乙型脑炎病毒(JEV)的PrM/E基因的HindⅢ-BglⅡ片段(2.1kb)插入到杆状病毒载体pAcUW31的BamHI位点,使外源基因置于多角体蛋白启动予下游,构建成转移载体pAcUW31JE,以Lipofectin作为共转染试剂,将纯化的pAcUW31JE与Bsu36I线性化的杆状病毒AcMNPV.LacZDNA共转染昆虫sf9经病毒蚀斑纯化技术和X-gal与中性红双重染色技术,随机  相似文献   
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