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1.
A grazing study was performed with the main objective of examining the effect of fenbendazole (FBZ) in a ‘dose and move’ system on nematode infections in calves with special emphasis on Dictyocaulus viviparus. Three groups of six calves were grazed from May to October 1993. One group (DM7) was treated with FBZ and moved to aftermath (pasture which had only been mown) 7 weeks after turnout. The second group (DM9) was similarly treated and moved 9 weeks after turnout and the third group served as untreated pasture control group (PC) and was moved to aftermath 9 weeks after turnout. FBZ treatment removed adult lungworms from DM7 and DM9. Tracer calves grazed during the first 7 or the first 9 weeks after turnout acquired mean burdens of 18 and 125 lungworms, respectively. In PC faecal larval counts increased until the end of August. Most of the animals in this group were then suffering from lungworm disease and emergency treatment with ivermectin was given. In both FBZ-treated groups, larvae reappeared in the faeces of some of the calves 4–5 weeks after treatment. Subsequent reinfection resulted in higher mean faecal larval counts in both groups 2 months after treatment, although variation in faecal larval counts was high. In DM7 values tended to be higher than in DM9. These higher larval counts were associated with mild signs of parasitic bronchitis in some calves of DM7, whereas no signs were seen in DM9. At the end of the experiment, all calves, and also a group of six permanently housed non-infected control calves (HC), were infected experimentally with 5000 D. viviparus larvae to evaluate development of immunity. The worm counts at necropsy showed that all calves on pasture had developed immunity. 相似文献
2.
The present study was designed to assess the persistent efficacy of ivermectin against gastrointestinal trichostrongyles and lungworm (Dictyocaulus viviparus) when given late in the season to young calves naturally exposed to infection on permanent pasture. The results suggest that ivermectin prevents the re-establishment of Ostertagia spp. for 2 to 3 weeks, but Cooperia spp. for only 1 to 2 weeks. Re-establishment of lungworm is prevented for a period of at least 3 weeks. The results are discussed in the light of recent studies on the ivermectin effects on experimental or early-season natural infections. 相似文献
4.
A combined epidemiology and control investigation was performed with parasite-free calves turned out in May on a permanent pasture naturally contaminated with lungworm larvae the previous year. Before the start the field was divided into two plots. One plot was grazed by 12 calves after the first week of May. The other plot was grazed by 12 calves turned out two weeks later. Both groups as well as the plots grazed by them were subdivided six weeks after turning out. Based on a predicted rise in the pasture larval contamination with infective lungworm larvae, one subgroup of each main group was given a tactical anthelmintic treatment six weeks and again eight weeks after their date of turning out. Patent infections from overwintered larvae were detected in both main groups after four weeks of grazing, but not in all individuals of the late turned-out group. The excreted larvae gave rise to pathogenic pasture larval contaminations on the two initial plots five to six weeks after turning out. In the control groups, early turning-out resulted in approx. 10 times higher larval recoveries in faeces and pasture compared to late turning-out. Seven to eight weeks after turning-out critical, severe parasitic bronchitis had developed in the early turned-out control group. In the late turned-out controls, clinical signs were obvious but not critical. Outbreaks were not observed in any of the experimental subgroups, and no larval excretion was observed among them within four to five weeks following treatments. Similarly, no larvae were recovered from their pastures two weeks after treatment and onwards. A third treatment was given to both experimental groups on the same date (August 21) to suppress gastrointestinal parasitism. However, the level of this infection, appeared moderate, probably due to comparatively low precipitation and extensive supplementary feeding given in late summer to compensate for scarcity of grass. 相似文献
5.
Glucocorticoid treatment of imported red deer (Cervus elaphus), seropositive to Infectious Bovine Rhinotracheitis (IBR) virus, reactivated a latent herpesvirus infection, which was transmitted to a seronegative deer with a fatal outcome. However the virus did not spread to cattle housed in close contact with the infected deer, and serological indication og infection in the cattle was observed only on direct nasal installation of virus. The virus isolate had characteristics in common with other Alpha herpesviruses and especially the Bovid Herpesvirus type 1 (BHV-1) but distinguished itself from the latter by its host specificity, serological reaction and genomic restriction fragment pattern (RFP). The host specific red deer herpesvirus was tentatively designated Cervid Herpesvirus type 1 (CHV-1). It was concluded that CHV-1 seropositive deer can be a threat to red deer farming, while in cattle the infection may only cause minor inconvenience through interference with the serological IBR diagnosis. 相似文献
6.
为了解湖南省生猪肺线虫的感染情况和危害程度,控制该虫的流行,对3个屠宰场猪进行解剖,采用常规的寄生虫实验室检查法检查气管、支气管、细支气管、肺脏等处的虫体。所获虫体用75%酒精保存,统计感染强度,计算感染率。检测结果显示,3个屠宰场生猪肺线虫感染率A(5.93%)B(4.26%)C(4.18%)。结果表明,湖南省生猪有肺线虫感染,应引起注意。 相似文献
7.
采用醋酸纤维素薄膜电泳法对青海高原10种草食家畜的血红蛋白(Hb)进行了比较研究。结果表明:(1)牛有三种Hb成分(A、B和C),构成HbA,AB,AC,B和BC五种表型;(2)牦牛有Hb F和S两种成分,构成单一的Hb FS型;(3)双峰驼有三种Hb成分(A,B_1和B_2),构成Hb A-B_1和A-B_1B_2两种表型;(4)梅花鹿和马鹿呈单一的Hb A型;(5)白唇鹿有Hb F和S两种成分,构成单一的Hb PS型;(6)马有Hb A_1和A_2两种成分,构成Hb A_1,Hb A_1~+A_2~-,Hb A_1A_2和Hb A_1~-A_2~+四种表型;(7)驴呈单一的Hb A_2型;(8)绵羊有三种Hb成分(A,B和C),构成Hb A,AB,B和AC四种表型;(9)山羊呈单一的Hb A型;(10)牛Hb B和马Hb A_1成分的相对电泳迁移率最大,双峰驼Hb B_2成分的迁移率最小。 相似文献
8.
2007年新疆某规模马鹿场部分马鹿发病,仔鹿多表现为消瘦、食欲下降,营养消耗性死亡;成年鹿多表现为咳嗽、喘气、体温升高、突然喘气死亡。通过病理解剖,细菌培养,接种动物等方法确诊该鹿场马鹿死亡原因是感染了牛型结核分枝杆菌,说明牛型结核分枝杆菌可以感染马鹿。 相似文献
9.
旨在从基因组层面揭示梅花鹿与欧洲马鹿的起源进化,找到与进化过程相关的信号通路并与表型进行关联.本试验以成年雌性梅花鹿与成年雄性欧洲马鹿染色体水平基因组作为研究对象,利用比较基因组学的方法对梅花鹿和欧洲马鹿基因组进行染色体共线性分析,获得两个物种间基因组序列的同源关系和基因组发生的染色体倒位现象,并对被倒位截断和在倒位内... 相似文献
10.
旨在利用基因分型测序(genotyping by sequencing,GBS)技术对梅花鹿、马鹿及其杂交后代(F1、F2)基因组的SNP特征进行分析。本试验采用GBS技术对梅花鹿(63个)、马鹿(12个)及其杂交后代(F1代112个,F2代38个,未知类型个体1个)共226个个体的血液基因组DNA进行测序,并利用本实验室前期110只梅花鹿、197只马鹿和1只F1代杂交鹿的测序数据,以梅花鹿全基因组为参考序列进行比对分析。结果,226个个体共产生Clean data 322.683 Gb,平均每个样品1 427.802 Mb;将所有样本作为一个群体检测SNP变异,共检测出SNP位点23 943 582个,质控过滤后得到SNP位点31 630个。对31 630个SNPs使用最大似然(maximum likelihood,ML)法构建的分子进化树显示,梅花鹿、马鹿、F1及F2代区分明显。对梅花鹿和马鹿的SNPs进行比对分析,筛选出可用于鉴别马鹿、梅花鹿、F1、F2的物种特异SNP位点1 032个(马鹿特异SNP位点474个,梅花鹿特异SNP位点558个),计算结果显示,F1代个体包含马鹿特异SNPs的比例主要在40%~60%之间,F2代个体含马鹿特异SNPs的比例主要在10%~30%之间,马鹿个体中不含梅花鹿的特异SNPs,梅花鹿中55.49%的个体不含马鹿特异SNPs,17.34%的个体含马鹿特异SNPs的比例低于1%,13.29%的个体含马鹿特异SNPs的比例在1%~10%之间,其余个体含马鹿特异SNPs的比例为10%~20%(其中有一个个体含马鹿特异SNPs的比例为33.3%)。该研究为花马杂交鹿后代的鉴定提供了可靠标记,并定量估计了F1和F2代个体含马鹿特异SNPs的比例,马鹿个体中不含梅花鹿的特异SNPs,这对梅花鹿、马鹿及其杂交后代(F1、F2)的鉴别具有重要意义。 相似文献
11.
通过大体解剖学和动物学头骨测定的方法对马鹿头骨进行观察,并与牛、羊、马、鬣羚相比较。雄性马鹿头骨呈狭长的角锥性,额骨上有角突,角突长而分叉;鼻骨较短前窄后宽,前端呈水平状,边缘呈锯齿状,这与马、鬣羚鼻骨不相似;上颌骨接近颌前骨部位有一个犬齿齿槽,齿槽部位有6个臼齿齿槽,下颌骨有6.5个,因此上颌骨臼齿齿列比下颌骨臼齿齿列短;颧骨的前下方、鼻骨的侧面、泪骨的前上方及上颌骨的后上方,形成一个等边三角形缝隙;缝隙与鼻腔之间由一形状不规则的薄骨片隔开,这与牛、羊、马、鬣羚都不相似。 相似文献
12.
In a material of free-living mammals collected and necropsied during the period 1934–1984, leukaemic neoplasia was found in 1 roe deer, 1 red deer and 15 brown hares. In order to determine the types of leukaemia, a histological reexamination of the tissues was performed. The two deer had the same type, while 4 different types were found in the hares. There was no evidence suggesting a contagious nature of the neoplasia or an accumulation of cases within certain geographic areas. 相似文献
13.
利用7个微卫星遗传标记,采用PCR扩增,12%非变性聚丙烯酰胺凝胶电泳、Sanguinetti银染法显色,对新疆塔里木马鹿亚种遗传多样性进行检测,统计各群体的等位基因组成、平均有效等位基因数(E)和平均基因纯合率(Rh),根据等位基因频率计算出各群体的平均遗传杂合度(h)、多态信息含量(PIC)和群体间的遗传距离,利用分子进化遗传分析软件(MEGA),采用邻结法(NJ)重建系统发生树。根据等位基因频率,利用PHYLIP(3.6)分析软件,采用最大似然法(ML)构建系统发生树,应用自举检验(bootstrap test)估计系统树中节点的自引导值(bootstrap value),并进行了系统发生分析。同时对部分马鹿群体个体基因型与产茸量之间进行了相关分析。结果表明:7个微卫星位点在3个塔里木马鹿中的多态信息含量除BMS2508和Celjp0023没有多态性,以及BM5004为中度多态外,其他4个微卫星均为高度多态,可作为有效的遗传标记用于3个塔里木马鹿群体遗传多样性和系统发生关系的分析。所有马鹿群体的平均PIC为(0.5196)、h(0.5552)和E(2.45),其基因多态性和遗传多样性相对丰富。塔里木马鹿35团群体与沙雅群体的血缘关系及遗传距离近于阿拉尔群体,3个塔里木马鹿群体的系统发育关系基本符合其地理分布和育成史。微卫星位点BM4208的166bp/185bp基因型和微卫星BM888的208bp/208bp基因型可以对塔里木马鹿35团群体高产茸量进行分子遗传标记。 相似文献
14.
研究在农户舍饲养条件下测定并对比研究了皮西黄、德西黄三元杂交牛及西黄二元杂交公牛各6头4月龄、6月龄、12月龄和18月龄的生长发育指标.结果表明:三元杂交牛18月龄活重达400kg以上,比二元杂交牛提高14.3%~20.4%;体高提高5.3%~10.8%,体斜长提高13.4%~16.7%,胸围提高19.2%~22.4%,管围提高6.5%~17.1%.三元杂交牛其它各年龄段比二元杂交牛体尺、体重均有大幅度的增长,故以上两种杂交组合是适宜当地发展肉牛生产的较佳杂交组合. 相似文献
15.
A 2-year, cross-sectional study was conducted to identify risk factors for Cryptosporidium sp. infection in bovine farms in central Italy. Faecal samples were collected on 248 farms, from 2024 calves and analysed using ELISA and immunofluorescent assay (IFA) commercial kits. In all 101 samples confirmed to be positive with IFA, the aetiological agent was identified as Cryptosporidium parvumand a large genetic variability was detected by subtype analysis. The prevalence of farm infection ranged from 3.4% to 35.6%. Univariate analysis showed a number of putative risk factors, including the type of farm, stalling of calves, late supply of colostrum, number of heads and contact between calves and adults. However, multivariate analysis confirmed that the higher risk for calves was associated with housing calves separately from their dams, a characteristic practice of dairy herd, whereas calves being nursed by their dams, a characteristic of cow-calf herd resulted as a protective factor. 相似文献
16.
We determined the complete nucleotide sequence of the mitochondrial genome of the semidomestic red deer ( Cervus elaphus) of New Zealand. The genome was 16 357 bp long and contained 13 protein‐coding genes, 12SrRNA, 16SrRNA, 22 tRNAs and a D‐loop as found in other mammals. Database homology searches showed that the mitochondrial DNA (mtDNA) sequence from the New Zealand semidomestic deer was similar to partial mtDNA sequences from the European, Norwegian ( C. e. atlanticus) and Spanish red deer ( C. e. hispanicus). Phylogenetic analysis of the mitochondrial protein‐coding regions revealed two well‐defined monophyletic clades in subfamilies Cervinae and Muntiacinae. However, red deer and Sika deer were not found to be close relatives. The analysis did identify the red deer as a sister taxon of a Samber/Sika deer clade, although it was more closely related to the Samber than the Sika group. 相似文献
17.
Fifty, 5–6 month-old lambs were randomly allocated to five equal groups. Three groups of lambs were immunised by three oxfendazole-abbreviated (artificial) infections of Trichostrongylus colubriformis and Ostertagia circutncincta. Group 1 was immunised with a high dose of larvae, Group 2 with a medium dose and Group 3 with a low dose. A fourth group was treated with oxfendazole only and a fifth group was not treated (control). All groups were grazed together on pasture naturally contaminated with nematode larvae. Immunisation significantly reduced the number of eggs per gram of faeces in all three groups, but the lowest faecal egg count was seen in Group 3 (immunised with the lowest number of larvae). Significantly better liveweight gains and wool weight were observed in Group 2 animals than in the control group. Of all anthelmintic-treated animals, only Group 1 lambs did not have a signscantly lower dag weight than controls. 相似文献
18.
为了确定适宜的湘南黄牛杂交组合,分别以安格斯、西门塔尔、短角、利木赞等4个肉用牛品种为父本,湘南黄牛为母本开展杂交试验,并对改良牛的体重和体尺进行测定,且进行了数据分析。结果表明:安本杂、西门塔尔、短角、利木赞牛对改良湘南黄牛的杂交优势十分明显,其中西门塔尔牛的改良效果最好。F1代公母牛初生、6月龄、12月龄、18月龄、24月龄体重较同龄湘南黄牛公母牛分别提高了72.62%和72.43%、50.25%和47.80%5、4.34%和59.46%、83.24%和74.68%、72.65%和76.23%,差异显著(P<0.05)。西门塔尔F1代公母牛24月龄体高、胸围、体斜长较同龄湘南黄牛公母牛提高了11.46%和12.02%、22.60%和23.51%、14.87%和15.54%,差异显著(P<0.05)。 相似文献
20.
[目的]探索肉牛改良大别山牛的育肥效果。[方法]从大别山黄牛及其与利木赞和夏洛来的杂交牛中分别选择体重150 kg左右的育肥牛各6头;均饲喂我们设计的同一饲料配方日粮,预试期同健胃驱虫法处理。[结果]在日常饲养管理相同的情况下,经30 d观察记载,大别山黄牛日增重0.46 kg、利杂牛日增重0.99 kg、夏杂牛日增重1.28 kg;两种杂交牛分别比大别山黄牛提高115.22%和178.26%。[结论]每增重1 kg毛重,大别山黄牛需精饲料5.43kg;而利杂牛和夏杂交牛只需要2.85 kg和2.38 kg。 相似文献
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