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1.
蜱传病呈全球分布，危害人类和动物健康。为了研究湖南省娄底市现存蜱媒病原体，于2021—2022年在湖南省娄底市采集1 395只微小牛蜱样本，提取蜱样品基因组DNA。选取蜱线粒体COI基因扩增特异性的基因片段，对微小牛蜱进行鉴定。为了对该蜱携带的病原进行检测，采用PCR方法对立克次体ompA和gltA基因，无形体groEL和23S rRNA基因，埃立克体groEL和16S rRNA基因，螺旋体16S rRNA和23S rRNA基因进行扩增，对阳性产物进行克隆测序，测序获得的基因序列进行系统发育分析来确定病原的基因型。结果显示，从蜱样本中检测出5种蜱传细菌病原，包括敬信立克次体(Candidatus Rickettsia jingxinensis)、中央无形体(Anaplasma centrale)、扁平无形体(Anaplasma platys)、米氏埃立克体(Ehrlichia minasensis)和宫本疏螺旋体(Borrelia miyamotoi)。其中敬信立克次体、米氏埃立克体和宫本疏螺旋体阳性率均为2.16%,扁平无形体阳性率为0.30%,中央无形体阳性率为5.79%。本研究利... 相似文献
2.
《中国兽医学报》2020,(9)
为了解四川省石渠县牦牛体表寄生蜱携带无形体与疏螺旋体的种类和感染情况。采集牦牛体表寄生蜱,经形态学和分子生物学鉴定,确定蜱种类。再采用巢式PCR分别扩增无形体科16S rRNA基因和疏螺旋体属的16S rRNA与flaB基因片段,并对阳性产物进行测序、比对和系统进化树构建,从而确定无形体和疏螺旋体的种类。结果显示,共采集到818只蜱,其中西藏革蜱占78.97%(646/818)、青海血蜱占21.03%(172/818)。所有蜱中有132只检出无形体,阳性率为16.14%;8只检出疏螺旋体,阳性率为0.98%;3只蜱混合感染牛无形体和疏螺旋体。经进一步分析,仅在青海血蜱中检测到牛无形体(Anaplasma bovis)、埃立克体(Ehrlichia)和疏螺旋体(Borrelia),其阳性率分别为6.98%(12/172),2.33%(4/172)和4.65%(8/172);仅在西藏革蜱中检测到绵羊无形体(Anaplasma ovis),其阳性率为17.96%(116/646)。此外,获得的疏螺旋体16S rRNA和flaB基因序列均与分离自日本大刺血蜱中的Borrelia sp.HM菌株亲缘关系最近。结果提示,四川石渠县存在牛无形体、绵羊无形体、埃立克体未定种以及疏螺旋体未定种,存在感染人的风险。 相似文献
3.
本研究旨在建立小亚璃眼蜱、亚洲璃眼蜱和残缘璃眼蜱的分子生物学鉴定方法,并探讨它们的系统发生关系。在新疆、内蒙古从动物体表采集寄生蜱,形态学鉴定后,PCR扩增测序获得3种璃眼蜱的16S rRNA及线粒体色素氧化酶亚基Ⅰ基因(cytochrome oxidaseⅠ,COⅠ)序列后进行同源性分析。用Mega 5.0和Mrbayes 3.2软件分别构建系统进化树,亚洲璃眼蜱、小亚璃眼蜱样本16S rRNA序列与GenBank中已知相应蜱虫16S rRNA序列聚类,而残缘璃眼蜱COⅠ序列与GenBank中已知残缘璃眼蜱COⅠ序列聚类,与形态学鉴定结果一致。在传统形态学分类的基础上,结合分子生物学鉴定方法能简易、准确鉴定小亚璃眼蜱、亚洲璃眼蜱和残缘璃眼蜱。 相似文献
4.
为了解广东地区家畜体表寄生蜱的种类及其携带病原情况,评估蜱媒病在广东省的传播风险,对该地区3个生境点(湛江、汕头、清远)的牛体寄生蜱进行了调查。2012年10月—2013年10月采用体表检视法和布旗法分别采集广东省不同地区的牛体表寄生蜱和牛舍环境周围游离蜱样本共109只,并进行实验室鉴定、检测。通过特异PCR方法分别检测无形体、莱姆病、巴贝西原虫、立克次体和Q热5种主要病原携带情况。结果显示:采集到的109只蜱虫样本均为微小牛蜱,其中湛江样品中检出6份无形体阳性样品,阳性率为5.5%(6/109);莱姆病、巴贝西原虫、立克次体和Q热均检测阴性。研究表明,广东省牛体寄生蜱种类相对单一为微小牛蜱,携带有阳性蜱传病原(嗜吞噬细胞无形体)。提示:广东省极有可能存在该病的自然疫源地,需要进一步调查并进行更深入的生态与分子流行病学研究。 相似文献
5.
为了对陕西省和辽宁省部分地区羊源蜱类及其携带病原体的流行情况进行分析,本试验采集了288份羊源蜱样本,采用形态学观察鉴定蜱种;采用分子生物学方法扩增巴贝斯虫18S rRNA、伯氏疏螺旋体16S rRNA、斑点热群立克次体ompA和无形体16S rRNA的基因序列,并结合核苷酸序列分析,确定所收集蜱样本中各类病原体的流行情况。结果显示,经鉴定288份羊源蜱样本均为长角血蜱。陕西省144份长角血蜱中携带巴贝斯虫、斑点热群立克次体和无形体,感染率分别为0.69%、21.53%和77.78%,且巴贝斯虫和斑点热群立克次体均与无形体复合感染;其中长角血蜱中携带Babesia microti、Candidatus Rickettsia longicornis、Uncultured Rickettsia sp. QH-122、Rickettsia endosymbiont of Haemaphysalis longicornis、Uncultured Anaplasma sp. ZJ06/2009、Anaplasma marginale、Anaplasma capra共7种病原体。辽宁省144份长角... 相似文献
6.
《动物医学进展》2020,(4)
为了解巴里坤县双峰驼体表蜱的种类及其携带病原,采集了巴里坤县双峰驼体表寄生蜱样本104只,在形态学分类的基础上,基于蜱的线粒体16S rDNA基因、梨形虫18S r DNA基因和立克次体16S rDNA基因,对48只蜱的DNA样本进行PCR扩增。结果显示,经形态学鉴定,104只蜱均为亚洲璃眼蜱;48个蜱DNA样本经PCR扩增和测序,均鉴定为亚洲璃眼蜱,存在9个基因型,以基因型1(n=24)、基因型2(n=4)和基因型3(n=12)为主要感染基因型,基因型4有2个样本,基因型5～9均有1个样本。48个蜱DNA样本检测出犬埃里克体1份,未发现梨形虫感染。结果表明,巴里坤县双峰驼体表蜱以亚洲璃眼蜱为优势种,存在遗传多样性,并发现亚洲璃眼蜱可携带犬埃里克体。 相似文献
7.
《中国兽医学报》2020,(4)
为了解新疆南疆部分地区不同蜱种携带斑点热群立克次体(spotted fever group Rickettsia,SFGR)情况,采用PCR技术扩增16S rDNA基因和SFGR外膜蛋白A(OmpA)基因,进行蜱种鉴定及SFGR检测。对测序阳性样本进行BLAST序列分析,应用DNAStar和Mega 6.0软件构建遗传进化树。结果显示:从新疆南疆9个县市共采集蜱1 340只,其种类包括3属4种,分别为图兰扇头蜱、边缘革蜱、银盾革蜱、亚洲璃眼蜱;在随机挑选的90份蜱DNA样本中共检测出57份SFGR阳性样本,其中阿拉尔市十一团、七连地区的阳性样本均来自犬体表寄生蜱,其余地区的阳性样本均来自绵羊体表寄生蜱。序列分析及遗传进化树显示,此次检测的亚洲璃眼蜱、边缘革蜱携带的SFGR与GenBank公布的SFGR疆内株Candidatus R.barbariae(登录号为MG668832.1)亲缘关系最近,处于同一分支;图兰扇头蜱携带的SFGR也同疆内株R.massiliae、R.conorii、Candidatus R.barbariae(MG668831.1、KP214024.1、MG668832.1)亲缘关系最近,处于同一分支;而银盾革蜱携带的SFGR与国外株R.raoultii(KT805295.1)亲缘关系最近,处于同一分支,并首次于新疆南疆绵羊寄生银盾革蜱中检出饶氏立克次体。本试验为该地区蜱传立克次体病的研究及防控提供重要依据。 相似文献
8.
立克次体目(Rickettsiales)中的立克次体属、埃立克体属和无形体属细菌分别能引起立克次体病、埃立克体病和无形体病,硬蜱是其主要传播媒介。在石河子市部分宠物医院及周边地区采集犬血及犬体表寄生蜱,通过PCR技术扩增蜱传立克次体目细菌16S rRNA基因,对所得结果进行测序并做系统进化分析。结果表明,扩增出立克次体345bp特异片段,无形体及犬埃立克体452bp特异片段,测序结果证实这些片段分别为立克次体、无形体和犬埃立克体。遗传进化分析显示,犬源立克次体、埃立克体及无形体石河子流行株分别与Rickettsiales bacterium(EF687768)、Ehrlichia sp.Yonaguni206(HQ697589.1)、Anaplasma(KJ410247.1、KJ410248.1、KJ410249.1)处于同一分支,分别属于立克次体、埃立克体、无形体的保守分支,提示与这些国内外流行株具有较近的亲缘关系。本研究基本理清了石河子地区犬中蜱传立克次体的感染和流行情况,为立克次体的防治提供了流行病学资料。 相似文献
9.
《中国兽医学报》2015,(12)
通过对璃眼蜱形态学及璃眼蜱属特异性基因(ITS-2)和其携带病原基因(Tams1)PCR扩增及其PCR产物的克隆、测序、同源性比较等,鉴定和检测采自新疆吐鲁番地区疑似牛体表璃眼蜱(n=50)及其携带病原状况。结果显示,采集的蜱虫经形态学鉴定均为小亚璃眼蜱,PCR扩增的璃眼蜱种属特异性ITS-2基因和环形泰勒虫Tams1基因序列大小分别为491 bp和534 bp。本试验获得的ITS-2序列与Gen Bank中已记载的小亚璃眼蜱ITS-2序列一致,与形态学鉴定结果相符,故这些璃眼蜱属于小亚璃眼蜱种(Hyalomma anatolicum)。在检测的50只璃眼蜱中,携带牛环形泰勒虫的有3只,阳性率为6%(3/50),并发现所扩增的携带病原目的基因序列与已登录记载的牛环形泰勒虫基因序列相似性为99%。结果表明,在传统形态学分类的基础上,借助分子生物学方法对璃眼蜱种属鉴定及无典型硬蜱种的鉴定具有简易、准确度高等特点,而且在璃眼蜱种属确定的基础上分离其携带的病原更有实际意义。 相似文献
10.
11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。 相似文献
12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections
of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal
(GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April
2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs
located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming
areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology
laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum
columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying
degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal
abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy
season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different
nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those
observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes.
But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the
results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia. 相似文献
13.
Rassnick KM Gieger TL Williams LE Ruslander DM Northrup NC Kristal O Myers NC Moore AS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2001,15(3):196-199
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks. 相似文献
14.
Davis MS Willard MD Nelson SL Mandsager RE McKiernan BS Mansell JK Lehenbauer TW 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(3):311-314
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large. 相似文献
15.
Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects 总被引：1，自引：0，他引：1
Johansson AM Gardner SY Levine JF Papich MG LaFevers DH Fuquay LR Reagan VH Atkins CE 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(6):887-895
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses. 相似文献
16.
B. Cinar Kul N. Bilgen J.A. Lenstra O. Korkmaz Agaoglu B. Akyuz O. Ertugrul 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2015,132(6):449-453
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded. 相似文献
17.
Troxel MT Vite CH Van Winkle TJ Newton AL Tiches D Dayrell-Hart B Kapatkin AS Shofer FS Steinberg SA 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(6):850-859
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma. 相似文献
18.
Waruiru RM Thamsborg SM Nansen P Kyvsgaard NC Bogh HO Munyua WK Gathuma JM 《Tropical animal health and production》2001,33(3):173-187
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round. 相似文献
19.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host. 相似文献