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1.
Parasites of the stomach in donkeys of the highveld of Zimbabwe   总被引:3,自引:0,他引:3  
Fourteen donkeys from a communal area of the Zimbabwean highveld were examined for stomach parasites during July and November of 1986 and January and April of 1987. All 14 animals were infected. Habronema muscae occurred in 12, Draschia megastoma in 11, H. majus in 9, Trichostrongylus axei in 9, Gasterophilus intestinalis in 14 and G. nasalis in 1 donkey. The lowest level of infection was in January for the helminths and in April for Gasterophilus larvae. The peak burdens of parasites were in July for Habronema spp. and in November for D. megastoma and Gasterophilus larvae. Infections with spirurid worms and Gasterophilus develop mainly from the middle of the rainy season to the beginning of the dry season (January to May/June). G. intestinalis seems to have an annual cycle.  相似文献   

2.
Before revised World Association for the Advancement of Veterinary Parasitology (WAAVP) guidelines on the detection of anthelmintic resistance can be produced, validation of modified and new methods is required in laboratories in different parts of the world. There is a great need for improved methods of detection of anthelmintic resistance particularly for the detection of macrocyclic lactone resistance and for the detection of resistant nematodes in cattle. Therefore, revised and new methods are provided here for the detection of anthelmintic resistance in nematodes of ruminants, horses and pigs as a basis for discussion and with the purpose that they are evaluated internationally to establish whether they could in the future be recommended by the WAAVP. The interpretation of the faecal egg count reduction test has been modified and suggestions given on its use with persistent anthelmintics and continuous release devices. An egg hatch test for benzimidazole (BZ) resistance is described. A microagar larval development test for the detection of benzimidazole and levamisole resistance provides third stage larvae for the identification of resistant worms. The sensitivity of these two tests can be increased by using discriminating doses rather than LD(50) values. Details are given of a PCR based test for the analysis of benzimidazole resistance in strongyles of sheep and goats, horses and cattle. Although promising for ruminant trichostrongyles, quantitative determination of gene frequency using real time PCR requires further development before PCR tests will be used in the field. Apart from faecal egg count reduction tests there are currently no satisfactory tests for macrocylic lactone resistance despite the great importance of this subject. Except for treatment and slaughter trials there are no validated tests for fasciolicide resistance or for the detection of resistance in cestodes.  相似文献   

3.
根据内蒙古农业大学职业技术学院运动马驯养与管理专业6年来实践教学模式的总结及经验的积累,客观分析了现阶段我国马术行业发展模式以及国内马术人才培养模式存在的问题,并从教学中总结出适应高职院校马术技能型人才的“全程定岗、两轮实训”的实践教学模式,以期为建立完善的人才培养体系提供参考。  相似文献   

4.
建国后,《〈中国新文学史〉教学大纲》第一次将中国新文学史作为一门学科确定下来,也是第一次将马克思主义与中国新文学史学科相结合,为20世纪50年代的文学史书写提供了一个范例。《大纲》在马克思主义指导下服从于新的意识形态,是毛泽东的政治、文艺思想在新文学研究领域的演绎。新文学史的“革命知识论”与阶级斗争话语模式也在《大纲》的指导下初步形成。  相似文献   

5.
Representative experiments from work undertaken to develop a synergistic mixture of trimethoprim and sulphaquinoxaline for the preventive treatment of certain poultry diseases are described. Sulphaquinoxaline in the diet for four days was shown to achieve at least an 85 per cent higher blood level than nine other sulphonamides in chicks, and the efficacies of various trimethoprim/sulphaquinoxaline regimes in the diet or in the drinking water were demonstrated against pasteurellosis, colisepticaemia and five kinds of coccidiosis. Regimes for bacterial diseases were begun one day before infection but those for coccidial diseases were begun on the same day as infection or later. Overall, a total dose of 30 mg/kg bodyweight/day (trimethoprim/sulphaquinoxaline = 1:3) controlled these seven diseases. The same treatment was also shown to control sulphaquinoxaline-resistant strains of Escherichia coli and Eimeria acervulina. Although both drinking water and food were used for drug administration, twice the inclusion rate was required in food to that in water for equivalent efficacy. The significance of different modes of expression of dosages for bacterial and coccidial diseases is explained.  相似文献   

6.
In total 31,669 blood samples were collected from 1187 flocks of 27 rare breeds of sheep in the UK, and their genotype profiles at the prion protein locus were determined. The frequencies of the five alleles varied widely among the breeds and some had only two of the alleles and others had all five; the average was three. The average allele frequencies across all 27 breeds were 49.7 per cent for ARR, 4.4 per cent for AHQ, 2.7 per cent for ARH, 37.4 per cent for ARQ and 5.8 per cent for VRQ. The highest frequencies for each allele were 90.7 per cent for ARR in the Leicester Longwool, 24.7 per cent for AHQ in the Hebridean, 68.7 per cent for ARH in the Manx Loghtan, 98.7 per cent for ARQ in the North Ronaldsay and 28.4 per cent for VRQ in the Boreray. All 27 breeds had the ARR allele, 21 had AHQ, 11 had ARH, 26 had ARQ and 20 had VRQ.  相似文献   

7.
OBJECTIVE: To determine clinical, enzymatic, and microbiologic effects of controlled-release localized administration of minocycline on dogs with periodontitis. ANIMALS: Five adult Beagles with periodontitis. PROCEDURE: After tooth scaling and root planing, 2 treatment, 1 placebo, and 1 control site were selected for each dog. Treatment sites (n = 10) received a periodontal formulation of minocycline hydrochloride, placebo sites (5) received ointment without minocycline, and control sites (5) did not receive ointment. Treatments were administered 4 times at weekly intervals. Peptidase activity and clinical and microbiologic effects were evaluated and compared among sites for 17 weeks. RESULTS: Bleeding of the gums on probing (BOP) and pocket depth (PD) improved at the treatment site and were maintained for 13 weeks after treatment. However, BOP and PD in placebo and control sites increased from weeks 9 to 17 Peptidase activity in the periodontal pocket decreased noticeably from week 1 to 17, compared with baseline values for the treatment site. However, peptidase activity for placebo and control sites increased and were above baseline values on week 9 and week 13, respectively. Total bacterial counts decreased by 90% for treatment sites and remained at that value for 13 weeks. However, for placebo and control sites, bacterial counts increased and reached the baseline value on week 17. CONCLUSIONS AND CLINICAL RELEVANCE: Increased peptidase activity is correlated with the progression of periodontitis in dogs. Treatment with minocycline, using a localized delivery system, was effective in dogs for at least 13 weeks after cessation of drug administration.  相似文献   

8.
Genetic parameters for mean and for environmental variation in egg weight, body weight, age at first egg, and egg production were estimated in eight layer lines. The data were recorded from years 1999-2007, with on average of 6500 birds per line. An iterative mean-variance REML method was applied with a sire-plus-dam model for mean, a sire model for variance, and a fixed effect of hatch within generation for both mean and variance. The estimated heritability of environmental variation averaged about 5% for body weight, 3% for egg weight, and 11% for age at first egg, but was inconsistent among the lines for egg production (0-15%). Correlations between means and variances were slightly positive for body weight, egg weight, and age at first egg; and strongly negative for egg production. Age at first egg had the highest heritability of environmental variation; and favourable correlations with egg production and with variation in other production traits indicate that reducing variation in this trait may have potential benefits for the breeding industry.  相似文献   

9.
松嫩平原假苇拂子茅无性系种群的年龄结构   总被引:11,自引:3,他引:8  
假苇拂子茅是典型的无性系禾草,分蘖节存活时间最多为4年,根茎存活的时间最多为3年;1龄级分蘖株生产力最高,1龄级 物质贮存能力最大,放牧场和割草场假苇拂子茅无性系种群的分蘖株均为增长型的年龄级蘖的物质生产;放牧扰动对假苇拂子茅无性系种群各龄级要茎的养分贮藏均有不利影响。割草场和放牧场假苇拂子茅潜在无性系种群均属于增长型的年龄结构。  相似文献   

10.
11.
OBJECTIVE: To evaluate the use of EDTA tubes for collection of blood samples for assays of secondary hemostasis in dogs. ANIMALS: 108 dogs of various ages, breeds, and sexes (19 healthy and 89 with abnormalities of secondary hemostasis). PROCEDURES: Blood samples were collected via cephalic venipuncture and transferred to sodium citrate tubes and EDTA tubes. Plasma was harvested from each type of tube for assays of concentrations of fibrinogen and D-dimer as well as prothrombin time, activated partial thromboplastin time, and antithrombin activity. Intra-assay and interassay precision and correlation coefficients for all hemostatic tests were calculated for each type of plasma sample. The effect of storage conditions on assay results for the 2 types of plasma samples was also evaluated. RESULTS: Results of hemostatic tests were highly correlated between citrated and EDTA-treated plasma samples. Intra-assay imprecision for all hemostatic tests with the exception of D-dimer concentration was < 10% for both citrated and EDTA-treated plasma samples; interassay imprecision was higher for EDTA-treated versus citrated plasma samples. Storage of plasma samples for 1 hour did not result in significantly different assay results for either type of plasma sample, but storage for 2 hours significantly affected values for EDTA-treated plasma samples. CONCLUSIONS AND CLINICAL RELEVANCE: Although evaluation of the sensitivity and specificity of hemostatic tests that use EDTA-treated plasma samples is required, EDTA may be a suitable alternative to sodium citrate as an anticoagulant for use in hemostatic testing in conditions in which tests could be performed within 1 hour after sample collection.  相似文献   

12.
科尔沁沙地植物的生态及分布区型结构分析   总被引:2,自引:0,他引:2  
姜汇  高凯  周立业  田迅 《草业科学》2018,35(2):311-322
为调查科尔沁沙地草原近年来植物多样性和植物生态特征,以反映该地区环境变化和植物生态适应性。本研究于2013年8月选取科尔沁沙地共56个样地,对样地植物按典型的科、属、种分类系统和株生长型、根生长型、Raunkiaer生活型、水分生态型及分布区型进行调查和分类,结果表明,科尔沁沙地具有典型的地面芽植物气候、中旱生生境条件、植物分布区系结构复杂的特征,共发现121种植物,隶属于31个科,6个株生长型,5个根生长型,6个生活型,5个水分生态类型和13个分布区型。其中,禾本科最多,占23.1%;菊科和豆科分别占22.3%和11.6%。株生长型结构以直立型种类最多,占37%;分枝型和丛生型分别占30%和19%。根生长型结构以直根型的种类最多,占61%;刷状根型和根茎型分别占22%和15%。生活型结构以地面芽植物种类最多,占35%;一年生植物和地面-地下芽植物分别占26%和14%。水分生态型以中生型植物种类最多,占44%;旱生型和中旱生型分别占26%和23%。分布区型结构中,蒙古-东北-兴安-华北分布区型(Mo-N-D-C)的植物种类占据首位,达30%;接下来是蒙古分布区型(Mo)和蒙古-东北-华北(Mo-N-C)分布区型,分别占18%和10%。结果表明,科尔沁沙地草原目前处于生态恢复的早期阶段,植物区系较复杂,水分环境没有发生重大变化,有利于该地区植物正向演替,但表层土壤生态环境依旧脆弱,一年生植物数量占绝对优势,应继续加强草地管理,合理保护和利用植物资源。  相似文献   

13.
OBJECTIVE: To apply an in vitro model for assessment of the solid-phase binding capacity of acetaminophen and thus assess the reliability of this marker for evaluation of solid-phase gastric emptying in vivo in animals. SAMPLE POPULATION: 4 test meals. PROCEDURES: A spectrophotometric method for detection of acetaminophen was validated and applied for assessment of the percentage retention of acetaminophen in the solid phase of 4 test meals. The gastric milieu was simulated by incubating each meal in artificial gastric juice for 2 hours in a shaking water bath maintained at 37 degrees C. Solid-phase retention was then assessed 3 times by measuring the amount of acetaminophen that had leached into the liquid phase. RESULTS: Acetaminophen was poorly retained in the solid phase of all the test meals examined in the study. There was also a large degree of variability in the percentage retention for each meal when the experiment was repeated 3 times. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of the results of this in vitro study confirmed that acetaminophen may not be an appropriate marker of solid-phase gastric emptying. The acetaminophen gastric emptying test should be applied only for the assessment of liquid-phase emptying in animals.  相似文献   

14.
Precise knowledge of the actual nutritional value of individual feedstuffs and complete diets for pigs is important for efficient livestock production. Methods of assessment of protein and energy values in pig feeds have been briefly described. In vivo determination of protein and energy values of feeds in pigs are time-consuming,expensive and very often require the use of surgically-modified animals. There is a need for more simple, rapid,inexpensive and reproducible methods for routine feed evaluation. Protein and energy values of pig feeds can be estimated using the following alternative methods: 1) prediction equations based on chemical composition; 2)animal models as rats, cockerels and growing pigs for adult animals; 3) rapid methods, such as the mobile nylon bag technique and in vitro methods. Alternative methods developed for predicting the total tract and ileal digestibility of nutrients including amino acids in feedstuffs and diets for pigs have been reviewed. This article focuses on two in vitro methods that can be used for the routine evaluation of amino acid ileal digestibility and energy value of pig feeds and on factors affecting digestibility determined in vivo in pigs and by alternative methods. Validation of alternative methods has been carried out by comparing the results obtained using these methods with those acquired in vivo in pigs. In conclusion, energy and protein values of pig feeds may be estimated with satisfactory precision in rats and by the two-or three-step in vitro methods providing equations for the calculation of standardized ileal digestibility of amino acids and metabolizable energy content. The use of alternative methods of feed evaluation is an important way for reduction of stressful animal experiments.  相似文献   

15.
Parafilariosis was first described in South Africa in 1964, thereafter being discovered at numerous localities in the country. When it became obvious that Parafilaria bovicola, for which no treatment was known, caused considerable economic losses, trials involving a series of compounds were conducted to identify candidate remedies. This paper describes an anthelmintic test for evaluating the efficacy of compounds for registration for field use. Recovery of Parafilaria worms is impractical for anthelmintic testing, and consequently the lesion sizes of treated and control groups of cattle are compared statistically, using appropriate statistical tests. The seasonal incidence of mature worm infection in cattle in South Africa is such that trials should commence after June and be completed before the end of January, allowing a lapse of 70 days between treatment and slaughter for resolution of the lesions. The presently available parafilaricidal compounds while of value for treating slaughter stock, when used alone will probably not be effective for control of infection in the field.  相似文献   

16.
This position paper delineates the expert recommendations of the Regulatory Affairs Committee of the American Society for Veterinary Clinical Pathology for the use of preclinical, clinical pathology endpoints in assessment of the potential for drug-induced hepatic injury in animals and humans. Development of these guidelines has been based on current recommendations in the relevant preclinical and human clinical trial literature; they are intended to provide a method for consistent and rigorous interpretation of liver-specific data for the identification of hepatic injury in preclinical studies and potential liability for hepatic injury in human patients.  相似文献   

17.
不同组合饲粮对绵羊瘤胃代谢参数的影响   总被引:1,自引:1,他引:0  
为研究不同饲粮组合,即对照饲粮(Ⅰ)、8%甜菜渣(Ⅱ)和8%苹果渣饲粮(Ⅲ)对瘤胃代谢参数的影响,选用3只安装永久性瘤胃瘘管的甘肃高山细毛羯羊(平均体质量22.5 kg),采用3×3拉丁方设计方案进行了试验。试验的3个饲粮循环均为预试期10 d,正试期9 d。结果表明, 1)各处理试羊的瘤胃液pH均值较相近(P>0.05)。2)采食饲粮Ⅱ羊瘤胃液丙酸摩尔比较低(P=0.109),其乙酸/丙酸高于Ⅰ(P<0.05)与Ⅲ(P>0.05);但采食3种饲粮的羊均属乙酸型发酵。仅饲粮Ⅱ的总挥发性脂肪酸时段变化近似典型的抛物线;Ⅰ、Ⅲ 的总挥发性脂肪酸峰值分别出现在食后3与5 h。3)处理间瘤胃液总氮、蛋白氮、氨氮、尿素氮的均值及细菌氮浓度的差异均不显著(P>0.05)。Ⅱ的总氮浓度始终较高,食后3,7 h呈现两峰;而其氨氮较低,食后1 h即出现峰值。Ⅰ、Ⅲ均在食后7 h达总氮最高值;Ⅰ未现峰值,Ⅲ于食后1,7 h出现峰值。可以认为:本试验饲粮间在瘤胃发酵类型与氮利用效率方面无显著差异,但仍显示出含8%甜菜渣饲粮,在稳定瘤胃环境、保持纤维素分解活性和氮利用方面有一定优势。  相似文献   

18.
Genotyping females and including them into the reference set for genomic predictions in dairy cattle is considered to provide gains in reliabilities of estimated breeding values for selection candidates. This should especially be true for low heritability traits. By the use of simulation, we extended a genomic reference set for an existing trait by including a fixed number of genotyped first‐crop daughters for one or two generations of reference sires. Moreover, we calculated results for the effects of a similar strategy in a situation where for a new trait the recording of phenotypes has recently started. For this case, we compared the effect of two different genotyping strategies: first, to phenotype cows but to genotype their sires only, and second, to collect phenotypes and genotypes on the same cows. We studied the effects on validation reliabilities and unbiasedness of predicted values for selection candidates. We found that by extending the reference set with genotyped daughters it is possible to increase the validation reliability of genomic breeding values. In the case of a new trait, it is always better to collect and use genotypes and phenotypes on the same animals instead of using only sire genotypes. We found that the benefits that can be achieved are sensitive to the sampling strategy used when selecting females for genotyping.  相似文献   

19.
通过实地考察和植物标本的采集与鉴定,并结合相关文献资料的查阅,对新疆西昆仑山禾本科植物物种多样性特点进行了研究。结果表明,新疆西昆仑山的禾本科植物共计37属137种,分别占新疆禾本科植物属、种总数的52.11%和42.55%,属种丰富度比较高;其中发现该区新记录植物6种。本区禾本科植物特有现象不明显,属的组成以仅含1种的属(17属17种)和少种属(13属35种)为主,共计30属52种,分别占属、种总数的81.08%和37.96%;中型属(4属32种)和较大属(3属53种)共计7属85种,分别占属、种总数的18.92%和62.04%,在种级水平占据明显优势,是该区系的主体。区系地理成分有6个分布类型和4个变型,以温带分布及其变型为主。植物生活型以多年生草本(116种,占84.67%)为主,其次为一年生草本(21种,占15.33%)。生态型以中生植物(63种,占45.99%)和旱生植物(61种,占44.53%)为主,显示其与草原、草甸的密切关系,另有少量湿生植物(13种,占9.49%)。说明该地区比较适合禾本科多年生的旱生和中生植物生长,且该区系的禾本科植物地理成分类型与该区所处地理位置为温带较吻合。  相似文献   

20.
The prediction of fertility is a primary goal in the field of reproductive medicine. The aim of the present paper is to describe the value of conventional and modern sperm analysis systems considering the process of fertilization. The classical assessment of motility and morphology enables the rough estimation of semen quality in order to select ejaculates for the use in artificial insemination. Recent methods for sperm diagnosis, such as fluorescent marking for the detection of sperm plasma membrane integrity, the hypoosmotic swelling test, and computer assisted semen analysis allow for the evaluation of a large number of spermatozoa and the assessment of sperm dynamics under in vitro-fertilization conditions. The oocyte penetration test investigates the ability of spermatozoa for capacitation, hyperactivation and acrosome reaction in vitro. The amount of specific seminal plasma proteins is related to fertility and thereby provides an additional semen evaluation method. For the use of a given semen test the specific in vitro condition has to be considered. In addition, the evaluated criteria relevant for the process of fertilization need to be defined. The combination of selected semen tests gives a higher accuracy for the prediction of fertilizing capacity compared with a single test.  相似文献   

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