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31.
汉中市野生兰科植物资源现状及保护开发策略 总被引:2,自引:0,他引:2
汉中市共分布野生兰科植物34属57种,分别占到陕西省的87.8%和68.3%,具有较高观赏价值的有兰属中的春兰和惠兰、独蒜兰属的独蒜兰,具有较高药用价值的有传统贵重中药天麻、白芨等。汉中市野生兰科植物总体资源量大、分布广,有着悠久的兰科植物栽培和开发利用历史,但近年来由于盗挖滥采现象较为严重,建议加强保护,建立野生兰科植物基因库,并加强人工栽培进行开发性的保护。 相似文献
32.
Yukino TAMAMURA-ANDOH Nobuyuki TANAKA Keisuke SATO Yoshino MIZUNO Nobuo ARAI Ayako WATANABE-YANAI Masato AKIBA Masahiro KUSUMOTO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(5):754
We examined the antimicrobial susceptibility of 848 Escherichia coli isolates from 237 feces samples of wild sika deer (Cervus nippon) captured between 2016 and 2019 in 39 of the 47 prefectures of Japan. Five of the 237 wild sika deer (2.1%) carried E. coli with resistance to at least one antimicrobial, and all the resistant isolates showed resistance to tetracycline. The resistant isolates contained antimicrobial resistance genes that were similar to those in E. coli derived from humans and farm animals. Although wild sika deer are not currently likely to be a source for the transmission of antimicrobial resistance in Japan, they can potentially mediate antimicrobial resistance spread by coming into contact with humans, animals, and their surroundings. 相似文献
33.
以猪瘟野毒E2蛋白为包被抗原、辣根过氧化物酶标记的猪瘟野毒单抗作为酶标抗体,建立检测猪瘟野毒抗体的阻断ELISA方法。猪瘟野毒E2最适包被浓度为0.03μg/mL,待检血清最适稀释度为1∶4,酶标猪瘟野毒单抗稀释度为1∶1 000。用建立的阻断ELISA方法检测369份临床阴性血清,计算阻断率,确定临界值,阻断率>40%为猪瘟野毒抗体阳性,阻断率≤40%为猪瘟野毒抗体阴性。用建立的ELISA方法检测84份血清,其中78份为免疫猪瘟疫苗的血清,6份为猪瘟病毒感染血清。结果显示,78份免疫血清均检测为猪瘟野毒抗体阴性,6份猪瘟感染血清均检测为猪瘟野毒抗体阳性。因此可初步判定该方法可用于鉴别诊断猪瘟病毒自然感染动物和C株疫苗免疫动物的血清抗体,并为临床检测猪瘟野毒抗体提供便捷、快速,精准的检测工具,对猪瘟的临床诊断、预防以及猪瘟净化工作具有非常重要的参考意义。 相似文献
34.
Chiho KANEKO Yasuyuki KANEKO Putu Eka SUDARYATMA Hirohisa MEKATA Yumi KIRINO Ryoji YAMAGUCHI Tamaki OKABAYASHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(4):680
We isolated two pseudorabies virus (PRV) isolates (designated OT-1 and OT-2) from two hunting dogs exhibiting neurological manifestations after eating the flesh of wild boar hunted in Oita prefecture, Kyushu Island, Japan. The isolates corresponded to a previously reported PRV (MY-1 strain) isolated from a hunting dog in neighboring Miyazaki prefecture, and it clustered into genotype II based on the glycoprotein C sequence. Our results suggest that this common PRV strain may have been maintained in wild boars on Kyushu Island even though domestic pigs in this area have attained an Aujeszky’s disease-free status. 相似文献
35.
2020年2月20日,贵州省道真县生态护林员在其境内的国家级大沙河自然保护区和国有林区发现多具野猪尸体。为弄清野猪死亡原因,防止可能出现的疫情在当地扩散,采用描述性流行病学方法,对本次野猪死亡事件展开调查。截至2020年3月4日,在该县3个镇8个村(社区)10个村民组,共排查发现23具野猪尸体,以体质量偏小的低幼龄野猪居多,约占70%;发现地点分布具有明显的聚集性和方向性;因大部分尸体高度腐败,仅从采集的1份病料中,检出猪圆环病毒核酸阳性,未检出猪瘟、口蹄疫、猪繁殖与呼吸综合征、非洲猪瘟等疫病病原;经排查,未发现野猪尸体附近的村(社区)生猪养殖户饲养的生猪发生异常发病死亡现象。经伽马分布估算,该县平均每天可能出现的死亡野猪数为0.44头(95%CI,0.28~0.64)。综上分析推测,野猪死亡既有经境内公路来往的生猪运输车辆及废弃物传入疫病导致的可能性,也不排除中毒或天气变化等其他因素的可能。由此建议加强公路沿线一带的林区排查,加大跨省公路车辆消毒力度,降低野猪死亡事件带来的潜在风险。 相似文献
36.
为了解规模猪场不同猪群的伪狂犬病病毒(PRV)感染情况及场区病毒载量分布特点,在山东省菏泽市某规模猪场,利用实时荧光定量PCR方法,对该猪场不同孕龄母猪、不同阶段生长猪群,以及各生产阶段场区环境,采集猪鼻拭子和场区环境拭子进行PRV-gE核酸检测,并对检测结果进行统计分析。结果显示:在294份猪鼻拭子中,检出42份PRV-gE核酸阳性,总阳性率为14.28%;母猪群PRV-gE阳性率为17.83%(23/129),且妊娠前后各阶段阳性率呈先上升后下降趋势,中期较高(24.00%),但差异不明显(P>0.05);不同阶段生长猪群的平均PRV-gE阳性率为11.52%(19/165),随日龄增加,阳性率也呈先上升后下降趋势,80~90日龄育肥猪最高(28.13%),与其他生长阶段猪群差异明显(P<0.05);除饲料、水源、上猪台和出猪台外,其他大部分场区环境均检测到PRV-gE核酸阳性;育肥猪群病毒载量最高,为3.6×105拷贝数/mL,其猪舍环境的病毒载量也较高,与其他环境及生长阶段猪群差异均明显(P<0.05)。结果表明,不同猪群包括免疫猪群均可遭受PRV野毒感染,尤其是母猪妊娠中期和猪育肥阶段早期,且大部分场区环境均可被污染。结果提示,规模猪场要加强各种猪群尤其是育肥猪群的伪狂犬病免疫,通过监测来调整和优化免疫程序,同时要加强生物安全,防止病毒传入和扩散。 相似文献
37.
Black-backed jackals (Canis mesomelas) are an abundant mesopredator on farmlands (croplands and rangelands) across South Africa. Given their adaptability in a changing anthropogenic landscape, knowledge of spatial movements can provide important ecological information on the species. We captured, collared and monitored five black-backed jackals in the Midlands of KwaZulu-Natal to determine their home range and habitat use in farmlands. The 95% fixed kernel (95% FK) home range sizes were large, showing a marked seasonal variation in movement. One adult male dispersed 150?km over two seasons (winter and spring) and thereafter settled into a home range that it maintained. Transient home ranges of males and juveniles were larger than resident home ranges. The mean resident home ranges (95% FK) across seasons for adult males, adult female and juvenile males were 11.4 ± 4.3 km2, 5.6 ± 0.36?km2 and 2.15 ± 0.45?km2, respectively. The mean transient home ranges (95% FK) of all the seasons for adult and juvenile males were 1 181.93 ± 575.81 km2 and 104.27 ± 35.64?km2, respectively. Adult jackal preferred croplands in spring, summer and autumn but avoided croplands in winter. Variable habitat use and large home ranges in our study confirmed the species’ ability to adapt to agricultural areas. 相似文献
38.
Kanae SHIOKAWA Chandika D. GAMAGE Nobuo KOIZUMI Yoshihiro SAKODA Kenta SHIMIZU Yoshimi TSUDA Kumiko YOSHIMATSU Jiro ARIKAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):221-230
The applicability of the recombinant LipL32 for serodiagnosis of leptospiral infection in field rodents was
assessed in this study. An immunodominant region of LipL32 was determined by monoclonal antibodies, and then,
truncated LipL32 (tLipL32) was designed to contain the region (87–188th amino acid). The tLipL32 was compared
between two recombinant expression hosts Escherichia coli and Pichia
pastoris in ELISA. With field rat sera, tLipL32 expressed by P. pastoris
(tLipL32p) had high antigenicity without background reactions, while tLipL32 expressed by E.
coli (tLipL32e) showed high background reactions, which were reduced by pre-adsorption of sera with
E. coli. To evaluate tLipL32-ELISA, field rat sera were tentatively divided into a
Leptospira infection positive (12 sera) and a negative group (12 sera) based on the results
from flaB gene PCR of kidney samples and WB with whole Leptospira cell.
Consequently, the sensitivity of tLipL32p-ELISA for field rat sera was 83% . A similar result was obtained
from tLipL32e-ELISA with adsorbed sera, (92%). However, sensitivity of tLipL32e-ELISA using sera without an
adsorption treatment was 50%. Regardless of the expression host, tLipL32-ELISA had 100% specificity and
sensitivity in experimentally infected laboratory rats. These results suggest that recombinant LipL32
expressed by P. pastoris is more applicable for serodiagnosis in field rats due to a lack of
background reaction. 相似文献
39.
为了解准噶尔盆地南部农区野生饲用植物资源,调查研究了该区域野生饲用植物的科属组成及其生活型和生态型特点,并对其适口性和营养价值进行了分析。结果表明:该区共有野生饲用植物34科145属214种,优势科有禾本科(38属71种)、藜科(18属22种)、菊科(15属21种)、豆科(14属19种)、苋科(8属11种)、十字花科(8属10种);生活型植物以草本植物(1~2年生124种,多年生62种)为主,占86.92%,木本植物有28种,占13.08%;生态型植物以中生为主(183种)。依据适口性可将该区野生饲用植物划分为优、良、中、低4个等级,其中优等95种、良等77种、中等36种、低等6种。营养成分丰富且适口性较好的饲用植物主要集中在禾本科(21种)、豆科(17种)和藜科(13种)。 相似文献
40.
Lindsay M. Clontz Anni Yang Sarah M. Chinn Kim M. Pepin Kurt C. VerCauteren George Wittemyer Ryan S. Miller James C. Beasley 《Pest management science》2023,79(10):3819-3829