基因拷贝数变异分析法研究大豆胞囊线虫病抗性位点qSCN3-3抗性相关基因

基因拷贝数变异(CNVs)是引起大豆品种对胞囊线虫抗性差异的因素之一,以抗大豆胞囊线虫病种质东农L~(-1)0以及感病种质黑农37、绥农10和绥农14为试验材料,利用实时荧光定量PCR法对大豆胞囊线虫抗性QTL位点qscn3-3内27个编码基因进行拷贝数变异分析,F测验表明15个目的基因在不同品种间存在拷贝数变异;抗感病品种PCR产物丰度相对值分析结果表明9个目的基因拷贝数在抗感病种质间存在显著的差异,推测其功能是通过编码抗病蛋白和富亮氨酸蛋白来实现大豆对大豆胞囊线虫相关抗性。     

一对姊妹线虫的杂交试验研究

基于李氏长尾线虫(Seinura liiHuang & Ye,2006)与吴氏长尾线虫(S.wuaeHuang & Ye,2006)是一对形态很相似的姊妹线虫,在原始描述之后,采用单一配对杂交方法来进一步探讨它们相互间的生殖关系。结果表明,李氏长尾线虫与吴氏长尾线虫在生殖上相互隔离,并且它们之间的生物学特性可能存在着较大差异;研究还表明,李氏长尾线虫与吴氏长尾线虫的生殖方式都为有性生殖。     

牛羊消化道线虫虫卵永久性玻片制作方法

通过对传统玻片标本制作方法的比较,研究牛、羊消化道线虫虫卵永久性玻片标本制作的最佳方法。采用琼脂糖粉分别配制10和15g/L的水溶液作为介质。载玻片上加入少许玻璃碎渣,用毛细吸管吸取一小滴虫卵液(约10个虫卵)于玻璃渣上,再吸取一滴介质于虫卵上,盖上小盖玻片(10mm×10mm),待介质凝固后,滴树胶并加盖玻片(18mm×18mm)。制作的玻片中虫卵经长时间保存后,能保持原来的形态及色泽,清晰可见,易于辨认。琼脂糖为介质的水溶性虫卵玻片的制作解决了传统方法制作玻片标本易出现气泡、空隙、发霉及虫卵变形等的问题,是虫卵玻片标本理想的制作方法,可供临床和教学实习使用。     

2种大豆胞囊线虫鉴定方法比较及分析

从计数方法、播种方法、鉴定准确性等方面对实用性较强的塑料钵柱法和酸性品红染色法2种大豆胞囊线虫鉴定方法进行了比较。塑料钵柱法鉴定时,可观察到大豆胞囊线虫病的主要发病特征,包括叶片变黄﹑植株矮小﹑根部有胞囊形成等典型症状。利用酸性品红染色法鉴定时未见叶片变黄,根部未见胞囊,但在20×显微镜下可检测处于二龄期的幼虫,可用于鉴定计数。2种鉴定方法对鉴别寄主具有同等区别抗感材料的能力,但在鉴别较大群体时品红染色法鉴定结果变异率低,同时在鉴定周期和效率上明显优于塑料钵柱法。因此,在对较大群体进行鉴定时,酸性品红染色法是一种便捷且准确性较高的鉴定方法。     

Assessment of anthelmintic resistance in nematode parasites of sheep and goats owned by smallholder farmers in eastern Ethiopia

The anthelmintic resistance status was investigated of nematode parasites of sheep and goats owned by smallholder farmers in communities that received breeding stock from a source where a high level of anthelmintic resistance has been reported. The investigation used the faecal egg count reduction technique, whereby suitable animals within each of eight separate communities were pooled to achieve the numbers required to conduct separate tests for both sheep and goats. Anthelmintics tested were albendazole (ABZ), tetramisole (TET), a combination (ABZ $+$ TET) and ivermectin (IVM), at the manufacturers' recommended dose rates. Results showed that there was no evidence of anthelmintic resistance in nematode parasites of either sheep an goats in any community. This indicates that dilution of resistant parasites imported with introduced breeding stock, and the low selection pressure imposed by the smallholder farmers themselves, has prevented anthelmintic resistance from emerging in nematode parasites of small ruminants in these communities.     

Congenital Aneurysmal Bone Cyst in a Foal

A 2-week-old female Thoroughbred foal was born with a firm, expansile, progressively enlarging mass involving the left hemimandible. Grossly, the mass was composed of variably sized cavernous spaces containing clotted blood and serofibrinous exudate, separated by fibrous and fibroosseous septa. Histologically, the spaces were lined by flattened to plump spindle cells and contained hemorrhage, fibrin, and multinucleated osteoclast-like cells. The septa separating adjacent cavernous spaces contained interlacing bundles and streams of spindle cells, multinucleated giant cells, hemosiderophages, mineral deposits, and spicules and trabeculae of reactive and poorly mineralized bone. A diagnosis of congenital aneurysmal bone cyst was made based on histologic features. The pathogenesis for the development of aneurysmal bone cysts is still undetermined, although spindle cells lining cavernous spaces in the foal exhibited negative immunolabeling for factor-VIII (F8) and positive immunolabeling for smooth muscle actin, suggesting vascular smooth muscle origin and possible blood flow disturbance.     

Dose confirmation studies for monepantel, an amino-acetonitrile derivative, against fourth stage gastro-intestinal nematode larvae infecting sheep

Monepantel is the first compound from the recently discovered amino-acetonitrile derivative (AAD) class of anthelmintics to be developed for use in sheep. Nine dose confirmation studies were conducted in Australia, New Zealand and Switzerland to confirm the minimum therapeutic oral dose of monepantel to control fourth stage (L4) gastro-intestinal nematode larvae in sheep (target species were Haemonchus contortus, Teladorsagia (Ostertagia) circumcincta, Teladorsagia trifurcata, Trichostrongylus axei, Trichostrongylus colubriformis, Trichostrongylus vitrinus, Cooperia curticei, Cooperia oncophora, Nematodirus battus, Nematodirus filicollis, Nematodirus spathiger, Chabertia ovina and Oesophagostomum venulosum). In each study, sheep infected with a defined selection of the target nematodes were treated with 2.5 mg monepantel/kg liveweight. Following euthanasia and worm counting, efficacy was calculated against worm counts from untreated control groups. The results demonstrate high (95 < 100%) efficacy of monepantel when administered orally to sheep at 2.5 mg/kg for most species tested. Efficacy levels against N. spathiger and O. venulosum were variable and failed to meet the required regulatory standard (≥90%) in some studies. Efficacy was demonstrated against L4 stages of nematodes known to be resistant to either benzimidazole and/or levamisole anthelmintics (macrocyclic lactone resistant isolates were not available for testing). The broad-spectrum activity of monepantel against L4 larvae of common gastro-intestinal nematodes in sheep and its favorable safety profile represents a significant advance in the treatment of parasitic gastro-enteritis in this animal species. No adverse effects related to treatment with monepantel were observed.     

捕食线虫性真菌--少孢节丛孢菌体外杀寄生性线虫幼虫的研究

对捕食线虫性真菌——少孢节丛孢菌(Arthrobotrys oligospora)菌株体外粪便捕杀马寄生性线虫幼虫进行了研究。结果表明：菌株可以在体外粪便中发育并发挥其捕食作用。在实验室条件下，其对寄生性线虫第一、二期幼虫的作用与对第三期幼虫的作用相比较．捕获致死速度快。菌株对马粪便中线虫幼虫的杀虫率高达98．7％；与对照组相比有显著差异。而且加入粪便的分生孢子数量在达到一定阈值后，再加入分生孢子，则杀虫率不再增加。此结论对捕食线虫性真菌今后临床的应用具有实际指导意义。     

Endectocide activity of a new long-action formulation containing 2.25% ivermectin+1.25% abamectin in cattle

The present work aimed to evaluate the endectocide activity of a new injectable long-action formulation, containing ivermectin (IVM) and abamectin (ABA). In each one of the four experiments performed, the following groups were formed: group I: 2.25% IVM (450 microg/kg)+1.25% ABA (250 microg/kg), group II: 3.15% IVM (630 microg/kg) and group III: control. Eighteen bovine naturally infected by gastrointestinal nematoda were selected for anthelmintic evaluation and necropsied on posttreatment day (PTD) 14 to estimate the total parasitic burden. For the Rhipicephalus (Boophilus) microplus field trial, 30 bovine were selected by means of counts of semi-engorged R. (B.) microplus and the therapeutic and residual efficacy evaluated by tick counts on PTDs 1, 3, 7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 77, 84 and 91. In the stall test, 15 calves were artificially infested with 5000 R. (B.) microplus (Mozzo strain) larvae three times a week and daily collections of all the engorged female ticks detached from each calf were performed until the PTD 80. Forty bovine naturally infected with Dermatobia hominis larvae were selected and the number of larvae was counted by visual and tactile inspection on PTDs 3, 7, 14, 28, 35, 49, 63, 77, 91 and 105. In this trial, a formulation containing 1% doramectin (200 microg/kg) was also used. IVM+ABA formulation and 3.15% IVM eliminated four of the eight species of nematode identified. The anthelmintic efficacy of the avermectins association against Haemonchus placei, Cooperia spatulata and C. punctata was 89.64%, 98.84% and 97.69%, while 3.15% IVM achieved 30.98%, 84.79% and 75.56%, respectively. The two formulations evaluated showed reduced acaricide action on the PTD 1 and 3, reaching high efficacy percentages from PTD 14 onward. The IVM+ABA showed efficacy above 95% in the period between PTDs 21 and 49. In the stall test, it observed no difference (P>0.05) between the two formulations regarding the R. (B.) microplus counts during the entire evaluation period. IVM+ABA reduced the number of ticks from the PTD 1 to 77 (P<0.05) and 3.15% IVM reduced (P<0.05) the tick number from PTD 4 up to PTD 80. The three endectocides showed no difference (P>0.05) regarding the number of D. hominis larvae and prevented this parasite reestablishment until PTD 105. These results indicate that the IVM+ABA association showed higher anthelmintic activity and similar efficacy against arthropods to the formulation containing 3.15% IVM.     

ACCURACY OF DIAGNOSTIC ULTRASOUND FOR DETECTION OF CYSTIC LESIONS: DETERMINATION USING RECEIVER OPERATING CHARACTERISTIC CURVE ANALYSIS OF FINDINGS IN PHANTOM STUDIES

Anechoic, spherical cystic lesions are important findings on ultrasound examination. In polycystic renal disease of cats, they may be the only ultrasonographic sign of disease. This study assesses the accuracy of ultrasound, as used in a veterinary setting, for the detection of cysts. Using a spherical lesion ultrasound imaging phantom and 7.5- to 8-MHz linear array transducers, images of cysts of 2- and 4-mm diameter were created at various imaging depths from 0 to 6 cm. These were digitized and given to a panel of readers for interpretation. Area under receiver operating characteristic curves were used to evaluate test accuracy. It was shown that test accuracy was different at different imaging depths and differed with machines of differing price category. It is suggested that when setting standards for quality control in ultrasound, criteria used might be better related to imaging outcome studies rather than to aspects of machine specification.