冬季新疆普氏野马消化道寄生虫感染情况及驱虫试验

为了了解新疆普氏野马消化道寄生虫感染情况及内外通灭(伊维菌素预混剂)对普氏野马消化道寄生虫的驱虫情况,试验于2018年1月份对新疆野马繁殖研究中心的65匹野马进行了冬季驱虫试验;试验采用饱和盐水漂浮法对65匹普氏野马进行了驱虫前后检查,分析其感染率以及跟踪检查给药后的驱虫率,并通过虫卵计数法(麦克马斯特氏法)分析其感染强度。结果表明:在采集的65份新鲜粪样中,含有消化道线虫虫卵的样品共54份,感染率为83%(54/65);初步检查出的虫卵包括马圆线虫、马副蛔虫、细颈三齿线虫和毛细线虫4种。其中马副蛔虫的感染率最高,为71%(46/65),两种虫种(马副蛔虫、毛细线虫)混合感染率达到43%,每克粪便虫卵数(EPG)为800～2 300个,三种虫种(毛细线虫、马副蛔虫、马圆线虫)混合感染率为17%,EPG为400～1 200个。驱虫后的65份样品,虫卵转阴率达到77%(50/65);虫卵减少率达到95%。说明内外通灭对普氏野马消化道寄生虫具有较好的驱虫作用。     

文昌鸡生态放养过程中驱虫程序的研究

采用虫卵漂浮法、麦克马斯特氏虫卵计数法对文昌鸡生态放养期间感染寄生虫的种类与粪便中虫卵数量进行监测。结果表明,文昌鸡生态放养感染的寄生线虫主要为鸡蛔虫和几种异刺线虫。自然条件下生态放养35 d后,每克粪便中寄生虫虫卵数（eggs per gram, EPG）达到了700,呈显著增长趋势。抽样宰杀30只鸡,检出18只感染鸡蛔虫成虫,感染率为60％,平均感染强度为8条/只。因此,建议整个生态放养期间驱虫3～4次为宜,首次驱虫时间为放养后25～30 d。     

吡喹酮和芬苯咪唑对圈养林麝莫尼茨绦虫的驱除试验

选择四川省某养麝场内16只感染莫尼茨绦虫的林麝,分别采用吡喹酮片剂(25 mg/kg体重,用药1次)和芬苯咪唑粉剂(10 mg/kg体重,1次/d,连喂3 d)进行药物驱虫试验。在投药前1天、投药后第7天和第14天采集其粪便,采用饱和食盐水漂浮法检测绦虫卵并进行虫卵计数,通过计算虫卵减少率和虫卵转阴率评估其驱虫效果。结果表明:在给药后第7天和第14天吡喹酮组的平均虫卵转阴率分别为85.71%(6/7)、100%(7/7),而芬苯咪唑组的平均虫卵转阴率分别为44.44%(4/9)、77.77%(7/9)。驱虫试验结果说明吡喹酮对林麝莫尼茨绦虫绦虫的驱虫效果较好。     

拜宠清和伊维菌素对自然感染犬弓首蛔虫临床药效比较

用伊维菌素和拜宠清分别对自然感染犬弓首蛔虫(Toxocara canis)的犬进行驱虫,以虫卵减少率和虫卵转阴率为指标判定驱虫效果,比较2种药物对犬蛔虫的驱虫效力。结果显示:从虫卵减少率和虫卵转阴率来看,第1次给药后第5、10、15天拜宠清组和伊维菌素组的虫卵减少率均超过95%,但在第1次驱虫15 d后的虫卵转阴率均不能达到100%。在第1次驱虫后2周进行第2次驱虫,驱虫后5～10 d虫卵转阴率均能达到100%。从排虫情况来看,伊维菌素组多在给药后6～8 d排虫,拜宠清组多在给药后2～4 d排虫。从剖检情况看,经两次驱虫,驱净率均能到达100%。研究表明,伊维菌素和拜宠清对犬弓首蛔虫均有很好的驱虫效果。     

成都地区3家马术俱乐部马匹的肠道寄生虫检测

本试验通过饱和盐水漂浮法和斯陶尔氏法对来自成都的A、B和C三个马术运动俱乐部的101份马匹粪样进行寄生虫检测,为赛马饲养管理者制定驱虫方案和检验驱虫效果提供重要参考。结果显示,肠道寄生虫总感染率为82.18%(83/101),3家俱乐部均检出圆线虫、马副蛔虫2种虫卵,混合感染率为14.85%(15/101)。圆线虫感染率为81.19%(82/101),每克虫卵数(EPG)为300个;马副蛔虫感染率为15.84%(16/101),EPG为555个。圆线虫在各年龄段的赛马均有分布,其感染率和感染强度随着年龄增加而降低。检出马副蛔虫的马匹多为幼龄马且多处于圆线虫和马副蛔虫混合感染的状态。结果表明,3家马术俱乐部马匹的寄生虫感染率和感染强度表现出明显差别。     

伊维菌素和双羟萘酸噻嘧啶对圈养大熊猫西氏贝蛔虫驱除试验

西氏贝蛔虫(Baylisascaris schroederi)是大熊猫体内最常见的一种寄生虫,对野生及圈养大熊猫危害很大,采用药物驱虫是目前控制圈养大熊猫蛔虫病的主要措施。为了评价伊维菌素和噻嘧啶对大熊猫西氏贝蛔虫的驱虫效果,本试验使用伊维菌素(膏剂,0.2 mg/kg体重,每天1次,连用2 d)、伊维菌素(片剂,0.2 mg/kg体重,每天1次,连用2 d)和双羟萘酸噻嘧啶(膏剂,10 mg/kg体重,每天1次,连用2 d)对雅安碧峰峡基地的圈养大熊猫进行了驱虫试验。在驱虫前3天和驱虫后10~15天采集大熊猫粪样,采用饱和硫酸镁离心漂浮法检测蛔虫卵,对阳性粪样进行虫卵定量测定,并通过计算虫卵转阴率评估驱虫效果。结果:伊维菌素(膏剂)组、伊维菌素(片剂)组和双羟萘酸噻嘧啶(膏剂)组的虫卵转阴率分别为44.44%、0.00%和80.00%。试验结果表明:双羟萘酸噻嘧啶(膏剂)对大熊猫蛔虫驱虫效果较好,伊维菌素(膏剂)对大熊猫蛔虫驱虫效果较差,伊维菌素(片剂)对大熊猫蛔虫驱虫效果最差。     

四种药物防治小尾寒羊消化道线虫的效果观察

为了探讨小尾寒羊消化道线虫发病规律和药物防治效果,筛选驱虫效果最佳药物,试验随机选取小尾寒羊600只,分为芬苯达唑粉组、伊维菌素注射液组、阿苯达唑伊维菌素预混剂组、多拉菌素注射液组和生理盐水对照组,每组各120只。每组在试验前7天进行粪便虫卵检查,用药开始后,在每次用药的第7天分别进行粪便虫卵检查1次,在整个试验期间共检查4次。粪便虫卵检查采用饱和盐水漂浮法,计算粪便虫卵数、每克被检粪样中虫卵数量(EPG),比较每个试验组每个检查阶段的虫卵转阴率。结果表明:各组试验羊在用药7 d后虫卵转阴率由高到低依次为阿苯达唑伊维菌素预混剂组、伊维菌素注射液组、芬苯达唑粉组、多拉菌素注射液组,分别为92.5%、90.8%、90.0%和89.1%,阿苯达唑伊维菌素预混剂防治效果确实可靠,药效持续时间长,优于其他试验组。说明临床用药在防治小尾寒羊消化道线虫方面,阿苯达唑伊维菌素预混剂防治该病效果优于其他试验药物,值得推广应用。     

细粒棘球绦虫感染终末宿主检测方法的评价

对细粒棘球绦虫感染家/牧犬常用的检测方法开展比对试验,并予以评估。对人工感染细粒棘球绦虫试验犬含卵粪样在不同时段用饱和蔗糖液(1.28 g/m L)漂浮虫卵,镜检;经化学药物驱虫,收集人工感染试验犬驱虫前、后粪样,流行病学调查中收集的家/牧犬粪样,用粪抗原抗体夹心ELISA检测试剂盒检测,同时,对检出的家/牧犬阳性粪样,再用虫卵漂浮法复检;通过氢溴酸槟榔碱下泻法检查家/牧犬感染细粒棘球绦虫虫体,同时,对下泻犬粪样用粪抗原检测和虫卵漂浮法进行复检。饱和蔗糖液漂浮虫卵最佳时段为2 h,可检出虫卵量与其他时段差异显著(P0.05);人工感染犬驱虫前、后粪样经粪抗原检测,OD值差异极显著(P0.01);对12 288份家/牧犬粪样进行粪抗原检测,阳性样品991份,感染率为8.1%(991/12 288),对991份阳性粪样进行虫卵漂浮法复检,检查出54份粪样中含虫卵。经下泻法检查312只家牧犬,其中,262只犬下泻,检查出27只犬感染细粒棘球绦虫成虫;对262份下泻犬粪样进行粪抗原检测,阳性29份;对262份下泻犬粪样用虫卵漂浮法检查,仅14份粪样检出虫卵。犬粪抗原抗体夹心ELISA检测犬感染细粒棘球绦虫可及时区分驱虫前、后感染状况,其更为安全、快捷、准确。     

3种驱虫药对陕北白绒山羊消化道线虫的驱虫效果比较

为了更好地了解常用驱虫药的驱虫效果,选择陕北白绒山羊开展驱虫研究。试验选取3种市场常用驱虫药(伊维菌素注射液、芬苯达唑粉、伊维菌素芬苯达唑预混剂),应用饱和食盐水漂浮法和虫卵计数法对陕北白绒山羊的消化道线虫驱虫前后的感染情况进行检测。结果表明,伊维菌素注射液组驱虫后虫卵转阴率为6.25%,感染强度由766.7降低至233.3;芬苯达唑组驱虫后虫卵转阴率为31.25%,感染强度由766.7降低至100;伊维菌素芬苯达唑预混剂组驱虫后虫卵转阴率为50%,感染强度由766.7降低至167.0。建议在陕北白绒山羊生产中将伊维菌素芬苯达唑预混剂作为消化道线虫的首选驱虫药。     

圈养蛇类寄生虫病感染调查

新动物园圈养蛇类寄生虫病感染情况备受关注。本试验旨在了解福州动物园圈养蛇类消化道寄生虫感染情况,调查寄生虫感染的种类和程度,为建立科学的防治方法和驱虫程序提供科学依据。本试验采用饱和食盐水漂浮法和自然水洗沉淀法收集虫卵,运用麦克马斯特计数方法对9种蛇类14条蛇共计20份粪便样本进行调查。寄生虫总感染率为100%(9/9),寄生虫种类为蛔虫、鞭虫、球虫、类圆线虫,其中以蛔虫的感染最为严重,此外,还从红尾蟒粪便中检查到螨虫幼虫。感染寄生虫的蛇类中,花岗岩蟒感染强度最高,蛔虫卵EPG为7650个/g;其次是黄金蟒蛔虫卵EPG为7500个/g;第三王锦蛇蛔虫卵EPG为3000个/g,鞭虫卵EPG为600个/g;其它虫卵EPG大多分布在25-1500个/g。     

福州动物园圈养鸟类肠道寄生虫调查

为调查福州动物园圈养鸟类消化道寄生虫感染情况,采集16种禽类31份粪便样品,应用饱和盐水漂浮法和自然水洗沉淀法收集虫卵,麦克斯特计数法对采集的粪便样本进行虫卵测定。检查结果显示,寄生虫感染阳性样品数有23份,占样品总数的74%。总共检出6种寄生虫感染,按感染例数从大到小排序为:球虫(9例)、吸虫(7例)、绦虫(6例)、线虫(5例)、鞭虫(4例)、纤毛虫(3例)。感染寄生虫的禽类中,孔雀的感染强度最高,EPG为9 150个/g;其次是巨嘴鸟,EPG为4 500个/g;第三是东方白鹳,EPG为3 300个/g。其他鸟类的EPG分布在0~2 100个/g。该调查结果为福州动物园圈养鸟类寄生虫病的防治以及制定科学的驱虫程序提供可靠的依据。     

The prevalence of internal and external parasites in pigs of different ages and sexes in Southeast District, Botswana

Botswana imports most pig-based products from neighbouring countries. Pig farming is limited by, among other things, the negative effect of parasites and diseases on production. The object of this study was to determine the prevalence of ecto- and endoparasites in pigs of different ages and sexes in the Southeast District of Botswana. Thirty-nine pigs were sampled for endoparasites and 19 for ectoparasites during a period of 2 1/2 months. Of all the pigs sampled, 54,55% were infected with Ascaris suum, 20,45% with Trichostrongylus spp. and 6,82% with Trichuris suis. Ascaris suum was found to be the most common endoparasite infesting both mature, i.e. 12 months and older, and young, i.e. less than 12 months old, pigs. Although not significantly different (P > 0,05), the prevalence of this parasite species was slightly higher (68,42% with an average of 1,023 +/- 545 eggs per gram (EPG) of faeces per pig) in mature than in young pigs (55% with an of average 1,500 +/- 846 EPG of faeces per pig). The prevalence of Trichostrongylus spp. was lower in mature (5,26% with 20 +/- 14 EPG of faeces per pig) than in young pigs (25% with 22 +/- 9 EPG of faeces per pig). The prevalence of T. suis was also lower in mature (0% infection) than in young pigs (15% with 9 +/- 4 EPG of faeces per pig). The prevalence of the three endoparasite species was not significantly different between the sexes A. suum (1,020 +/- 883 v. 1,503 +/- 522 EPG of faeces per pig), Trichostrongylus spp. (24 +/- 14 v. 18 +/- 8 EPG of faeces per pig) and T. suis (11 +/- 6 v. 2 +/- 4 EPG of faeces per pig) for male and female pigs respectively. Sarcoptes scabiei was the only ectoparasite identified on the pigs sampled for external parasites. It infested 40% of all pigs but the infestation on young pigs (70%) was higher than on the mature ones (33,33%). Since the infection of internal and external parasites was similar in young and old pigs of both sexes, controlling parasites is of great importance since these generally lead to reduced production and are also of public health concern. It is recommended that a further study be carried out to investigate the effect of internal and external parasites on productivity.     

Resistance of Santa Ines and crossbred ewes to naturally acquired gastrointestinal nematode infections

This trial was carried out in Piracicaba, São Paulo State, Brazil, to comparatively evaluate the degree of resistance to naturally acquired gastrointestinal nematode infections in sheep of the following genetic groups: purebred Santa Ines (SI), SI crossbred with Dorper (DO × SI), Ile de France (IF × SI), Suffolk (SU × SI), and Texel (TE × SI). Fifteen ewes from each group were raised indoors until 12 months of age. At this age, they were moved to pasture that was naturally contaminated by nematode infective larvae and were evaluated from December to May, 2007. Rainfall ranged from 267 mm in January to 37 mm in April. Maximum and minimum mean temperatures ranged from 32.5 °C to 19.0 °C in March and from 25.9 °C to 12.8 °C in May. There was an increase in the mean number of eggs per gram of feces (EPG) after animals were placed on pasture with significant difference between the SI (80 EPG) and IF × SI (347 EPG) groups in January; and the DO × SI (386 EPG) and TE × SI (258 EPG) groups in May. The highest mean fecal egg count (FEC), 2073 EPG, was recorded for the TE × SI group in February. All groups showed a progressive reduction in body weight throughout the experiment of 12.0% (TE × SI) to 15.9% (SU × SI). In general, the animals with the highest FEC presented the lowest packed cell volumes (PCV); the highest correlation coefficient between FEC × PCV occurred in the SU × SI sheep in January (r = −0.70; P < 0.01). Similarly, there was an inverse relationship between FEC and blood eosinophil values, with the highest correlation coefficient in the TE × SI sheep in February (r = −0.64; P < 0.05). Immunoglobulin G (IgG) levels against Haemonchus contortus antigens increased in all groups as a result of the exposure to parasites and remained relatively constant until the end of the study, with the exceptions of SU × SI and TE × SI, which showed a rise in IgG levels during the last sampling that coincided with a reduction in mean FEC. In conclusion, crossbreeding Santa Ines sheep with any of the breeds evaluated can result in a production increase and the maintenance of a satisfactory degree of infection resistance, especially against H. contortus and Trichostrongylus colubriformis, the major nematodes detected in this flock.     

Comparative efficacy of santonin and piperazine against Neoascaris vitulorum in buffalo calves

An investigation was undertaken to evaluate the comparative efficacy of single dose treatment with santonin and piperazine against naturally acquired Neoascaris vitulorum in sixty-two buffalo calves of 20–60 days of age. Santonin was administered orally in doses of 5 mg, 10 mg and 15 mg/kg body weight to thirteen, eighteen, and sixteen buffalo calves, respectively. As a control, piperazine (88 mg/kg) was given by drench to a group of fifteen infected buffalo calves. Pretreatment and post treatment faecal eggs per gram (EPG) counts were determined by the Stoll's technique. The percentage reductions in EPG counts on the third and seventh days after administration of the two drugs were calculated. The percentage reduction in EPG counts in the piperazine treated group on the third day was 82 ± 15, 90.2 ± 3 and 91.3 ± 2.3% while on the seventh day these values were 88 ± 16, 97 ± 3, and 98 ± 2% in high, moderate and heavy infection calves, respectively. Treatment with santonin at 5, 10 and 15 mg/kg body weight also reduced the EPG counts. The percentage reduction in EPG counts in the calves treated with 15 mg/kg of santonin on the third day was 92.3 ± 18, 95.8 ± 7 and 93.5 ± 4% while on the seventh day these values were 100 ± 0, 100 ± 0 and 99.7 ± 2% in high, moderate and heavily infected calves, respectively. Both piperazine and santonin were associated with some side effects like diarrhoea, restlessness, etc. but their percentage incidence was not significantly different from each other. These findings suggest that santonin in a 15 mg/kg dose has an efficacy similar to piperazine given at the 88 mg/kg dose level for the treatment of ascariasis in buffalo calves.     

The bias, accuracy and precision of faecal egg count reduction test results in cattle using McMaster, Cornell-Wisconsin and FLOTAC egg counting methods

The faecal egg count reduction test (FECRT) is the recommended method to monitor anthelmintic drug efficacy in cattle. There is a large variation in faecal egg count (FEC) methods applied to determine FECRT. However, it remains unclear whether FEC methods with an equal analytic sensitivity, but with different methodologies, result in equal FECRT results. We therefore, compared the bias, accuracy and precision of FECRT results for Cornell-Wisconsin (analytic sensitivity = 1 egg per gram faeces (EPG)), FLOTAC (analytic sensitivity = 1 EPG) and McMaster method (analytic sensitivity = 10 EPG) across four levels of egg excretion (1-49 EPG; 50-149 EPG; 150-299 EPG; 300-600 EPG). Finally, we assessed the sensitivity of the FEC methods to detect a truly reduced efficacy. To this end, two different criteria were used to define reduced efficacy based on FECR, including those described in the WAAVP guidelines (FECRT <95% and lower limit of 95%CI <90%) (Coles et al., 1992) and those proposed by El-Abdellati et al. (2010) (upper limit of 95%CI <95%). There was no significant difference in bias and accuracy of FECRT results across the three methods. FLOTAC provided the most precise FECRT results. Cornell-Wisconsin and McMaster gave similar imprecise results. FECRT were significantly underestimated when baseline FEC were low and drugs were more efficacious. For all FEC methods, precision and accuracy of the FECRT improved as egg excretion increased, this effect was greatest for McMaster and least for Cornell-Wisconsin. The sensitivity of the three methods to detect a truly reduced efficacy was high (>90%). Yet, the sensitivity of McMaster and Cornell-Wisconsin may drop when drugs only show sub-optimal efficacy. Overall, the study indicates that the precision of FECRT is affected by the methodology of FEC, and that the level of egg excretion should be considered in the final interpretation of the FECRT. However, more comprehensive studies are required to provide more insights into the complex interplay of factors inherent to study design (sample size and FEC method) and host-parasite interactions (level of egg excretion and aggregation across the host population).     

Precision, repeatability and representative ability of faecal egg counts in Heterakis gallinarum infected chickens

This study investigated whether a precise and repeatable quantification of Heterakis gallinarum egg excretion, which considerably reflects the actual worm burdens, can be achieved based on collection of the daily total amount of faeces from chickens. Three-week-old birds (N=64) were infected with 200 embryonated eggs of H. gallinarum, and placed into individual cages 3 wk after infection for 5 wk to collect daily faeces (N=2240). The total daily faeces was mixed and a randomly taken sample per bird was analyzed to estimate the numbers of eggs per gram of faeces (EPG) and total number of eggs excreted within 24h (EPD). A total of 235 daily faecal collections were randomly selected and further examined to determine between and within sample variations of EPG counts as a measure of precision. For this, two random faecal samples were taken from the daily produced faeces by a bird, and the EPG was determined for each of the samples (EPG1 and EPG2). The second faecal sample was analyzed once more to determine a parallel EPG2 count (EPG2a) of the suspended sample. Precision of an EPG count was defined as its relative closeness to the average of two EPG counts using a relative asymmetry index (Index(EPG)). At an age of 11 wk, i.e. 8 wk p.i. the birds were slaughtered and their worm burdens were determined. There were no significant differences between EPG1 and EPG2 (P=0.764) nor between EPG2 and EPG2a (P=0.700), suggesting that the differences between or within the samples were not different from zero. Correlations between EPG counts, as between and within sample coherences, were r=0.85 and r=0.86, respectively. Precision of EPG counts, as measured by Index(EPG), was not influenced by consistency (P=0.870) and total amount of faeces (P=0.088). However, concentration of eggs in faeces (mean EPG) had a significant effect on the precision of the EPG counts (P<0.001). Similar results were also observed for the within sample precision (Index(EPG2)). A segmented regression analysis indicated an abrupt change in the precision of EPG counts as the response to changing egg concentration in the examined faecal samples. The precision of analyses remarkably heightened up to a breakpoint with an EPG count of ≤ 617. A similar breakpoint was also determined for within sample precision (EPG2 ≤ 621). Moderate repeatabilities (R=0.49) for EPG and EPD were estimated in the first week of egg excretion, whereas the estimates were higher (R=0.67-0.84) in the following weeks. Correlations between number of female worms with daily measured EPG and EPD increased to an almost constant level (r ≥ 0.70; P<0.05) in a few days after the nematode excreted eggs and predominantly remained so for the rest of the sampling period. It is concluded that mixing daily total faeces provides samples with random homogenous distribution of H. gallinarum eggs. Precision of the EPG counts increases as the egg concentration in faecal sample increases. Egg excretion of H. gallinarum, quantified either as EPG or EPD, is highly repeatable and closely correlated with the actual worm burden of birds starting as early as in 5 th wk of infection.     

川西北红原县和理塘县牦牛4类体内寄生虫感染的研究

采集川西北阿坝州红原县和甘孜州理塘县总计402份牦牛粪便样本,采用廖氏计数法（改良）对4类常见体内寄生虫虫卵进行形态学观察并计数,以了解该地区牦牛体内寄生虫感染情况。结果表明,红原县牦牛体内线虫、绦虫、吸虫、球虫虫卵或卵囊（EPG或OPG）的平均感染量分别为11.59、23.77、42.45和14.72,总感染量为92.53（48.91~154.90）;平均感染率分别为18.01%、36.62%、44.68%、17.37%,总感染率为76.39%,表明吸虫是红原的优势寄生虫虫种,绦虫也是重要虫种。理塘县牦牛线虫、绦虫、吸虫、球虫的虫卵或卵囊（EPG或OPG）的感染量分别为52.38、13.10、20.24和1.19,总感染量为86.90;感染率分别为52.38%、19.05%、23.81%和2.38%,总感染率为78.57%,表明线虫为该地区的优势虫种。红原县和理塘县两地牦牛体内寄生虫虫卵感染主要以单一感染和二重感染为主,二者的总和分别为69.31%和78.57%,分别占总感染率的90.73%和100%。本研究结果证实牦牛寄生虫病目前仍是危害牦牛生产和当地牧民健康的一类重要疫病。该研究丰富了川西北高原地区牦牛体内寄生虫病的流行病学资料,为该地区牦牛寄生虫病的防控提供了理论依据。     

Study on Infection of 4 Kinds of Internal Parasites in Yaks in Hongyuan and Litang County of Northwest Sichuan Province

To understand the infection of main internal parasites in yaks, total of 402 fecal samples of yaks were collected from Hongyuan county in Aba prefecture and Litang county in Ganzi prefecture, the morphological characteristics of 4 kinds of internal parasitic eggs or oocysts were observed and the numbers of them were counted using the modified Liao's counting method. The results showed that in yaks of Hongyuan county, the average infection intensities of EPG or OPG of nematodes, cestodes, trematodes and coccidian were 11.59, 23.77, 42.45 and 14.72, respectively, and the total number of infections was 92.53 (48.91 to 154.90); The average infection rates of eggs or oocysts of these 4 kinds of parasites were 18.01%, 36.62%, 44.68% and 17.37%, respectively, and the total infection rate was 76.39%, which proved that trematodes was the dominant parasitic species and cestodes was also an important one in this area. In yaks of Litang county, the average infection intensities of EPG or OPG of nematodes, cestodes, trematodes and coccidian were 52.38, 13.10, 20.24 and 1.19, respectively, and the total number of infections was 86.90, the average infection rates of eggs or oocysts of these 4 kinds of parasites were 52.38%,19.05%,23.81% and 2.38%, respectively, the total infection rate was 78.57%, which proved that nematodes was the dominant parasitic species in this area. The infection patterns of internal parasitic eggs or oocysts in yaks in Hongyuan and Litang county were all mainly the single and double infection, the sums of these two patterns were 69.31% and 78.57%, respectively, which accounted for 90.73% and 100% of the total infection rate, respectively. The results in this paper showed that the parasitic disease in yaks was still an important disease harmful to yak production and herdsman health, meanwhile these results enriched the epidemiological data of the internal parasitic disease of yaks in Northwest plateau of Sichuan province and provided a theory basis for prevention and control of parasitic diseases in yaks in this area.     

Fatal gastrointestinal parasitism in goats: 31 cases (2001-2006)

OBJECTIVE: To evaluate signalment, history, clinical and pathologic findings, and seasonal weather patterns in association with fatal gastrointestinal parasitism in goats. DESIGN: Retrospective case series. ANIMALS: 152 goats that were > 1 day of age. PROCEDURES: Characteristics including age and counts of coccidia oocysts and trichostrongyle ova (eggs) per gram of feces (EPG) in goats that died because of gastrointestinal parasitism and goats that died because of other causes were compared. Weather data and annual incidence of caprine fatal gastrointestinal parasitism were investigated. RESULTS: Death was attributed to gastrointestinal parasitism in 31 of 152 (20%) goats (median age, 5 months; range, 1 month to 7 years); deaths were attributed to coccidiosis (n = 7 goats; median age, 4 months; median EPG, 2,225), trichostrongylosis (6 goats; median age, 1.25 years; median EPG, 3,700), or dual infection (18 goats; median age, 6.7 months; median EPG, 8,088 coccidia and 5,475 trichostrongyles). Sudden onset of weakness or death was a common historical finding; diarrhea was evident in 15 goats. Common postmortem findings in these goats included cachexia, tissue pallor, poorly formed feces, and mesenteric lymphadenomegaly. Wet weather in spring and summer was associated with increased annual incidence of fatal gastrointestinal parasitism in goats. CONCLUSIONS AND CLINICAL RELEVANCE: Gastrointestinal parasitism is an important cause of death in goats. Clinical signs may not develop until just prior to death, and diagnosis is achieved via parasitologic evaluation of feces and necropsy. Seasonal weather patterns should be considered on an annual basis when designing parasite control programs for goats.     

广东省部分地区马肠道寄生虫感染情况调查

【目的】调查广东省内部分地区马匹寄生虫感染情况,探索区域内马匹寄生虫感染优势虫种、感染情况和耐药情况,为区域内马肠道寄生虫病的防治提供参考。【方法】采用饱和食盐溶液漂浮法和饱和蔗糖溶液漂浮法对广东省内7个城市24个马术俱乐部375份新鲜马粪样品进行处理,光学显微镜下观察虫卵/卵囊的形态结构特征并进行分类,并根据麦氏计数法计算每克粪便中虫卵/卵囊数（EPG）,统计感染率和感染强度。对EPG＞500的阳性样本进行粪便虫卵减少量计数试验（FECRT）,以评估各马术俱乐部流行寄生虫耐药情况。提取5份＜1岁幼驹的粪便样本DNA,利用巢式PCR检测样品是否存在隐孢子虫感染。【结果】375份样品中有120份样品呈寄生虫虫卵/卵囊阳性,总感染率为32.00%。共检出4种肠道寄生虫,分别为圆线虫、马副蛔虫、类圆线虫和马蛲虫,总感染率分别为30.40%、3.70%、0.80%和0.30%。1~4岁马匹感染率显著高于其他年龄段（P＜0.05）,但不同性别马匹寄生虫感染情况无显著差异（P＞0.05）。受调查马匹感染强度以低排卵（EPG＜200）为主,占马匹总数83.47%。FECRT结果显示,样本所在马术俱乐部常用驱虫药（主要成分为伊维菌素、阿苯达唑）有效,未见耐药现象。5份＜1岁幼驹的粪便样本隐孢子虫巢式PCR检测均为阴性。【结论】广东省部分地区马术俱乐部道寄生虫防控情况总体良好,区域内各马术俱乐部寄生虫防控效果存在差异,建议区域内各马术俱乐部加强马肠道寄生虫监测工作,依据本场监测情况合理用药,避免场内流行寄生虫对所用驱虫药物产生耐药性。