驯鹿狂蝇蛆(Cephenemyia trompe)超微形态结构

利用扫描电子显微镜技术对驯鹿狂蝇蛆(Cephenemyia trompe)的形态结构进行了观察。结果表明,驯鹿狂蝇蛆体表的棘刺随所在不同部位而形态不一,但刺基较大,多数为圆丘形;期幼虫口钩周缘有内外2圈三角形口前齿;期幼虫与期幼虫相比,棘刺数量增多,棘刺变大;期幼虫后气门板上在光学显微镜下的所谓"气孔"实质上是个膜状结构,中间有一道弧形气缝。     

蒙古马马鼻狂蝇三龄幼虫的形态学和分子生物学研究

为了研究蒙古马鼻狂蝇三龄幼虫的形态学和分子生物学特性,利用扫描电镜对马鼻狂蝇三龄幼虫的头部、尾部和第三体节棘刺进行形态观察;并选取蒙古马鼻狂蝇三龄幼虫,提取其线粒体CoxI基因和16S rRNA基因,进行碱基组成分析和系统发育树构建。结果发现:(1)马鼻狂蝇气门板上的结构不同于其它狂蝇,其气门板上由硬化的骨质形成期的孔缘围绕,气门肌肉使得气门板上的开口呈垂直形态,在后气门板上有几排小刺;头部有1对乳突状感受器,其上分布着1对疣状乳突;(2)蒙古马鼻狂蝇三龄幼虫的CoxI、16S rRNA基因均与GenBank数据库中提交的马胃蝇、纹皮蝇、鹿狂蝇、羊狂蝇等在系统发育树中分开。虽然蒙古马鼻狂蝇三龄幼虫形态上跟紫鼻狂蝇很像,但是其分子生物学特点说明它可能是一个新变种。     

扫描电子显微镜下对羊狂蝇三期幼虫的形态观察

应用扫描电子显微镜对青海高原不同海拔地区寄生于羊体的狂蝇三期幼虫进行了形态学观察,三个在地理上相距较远的8个三期幼虫样品的扫描电镜微观结构显示,头部指状凸起上的感觉器官其基本特征形态显示一致,气门板上的气孔和棘刺的分布排列个体虽有细小差别,但其他主要观察部位未发现明显不同的形态特征,从而确信它们为同一虫种.     

青海绵羊狂蝇幼虫的COI基因多态性分析

利用分子生物学技术对青海省互助县、贵德县和玉树县三个不同海拔、生态环境的绵羊感染狂蝇幼虫的线粒体COI基因种属特异性序列进行了研究。结果显示:10个狂蝇幼虫扩增出长度为309bp的序列,测序结果表明这些绵羊狂蝇幼虫的COI基因相似性在99.4%~99.7%之间。     

羊狂蝇蛆病的研究及防治概况

本文对若干年来省内外羊狂蝇蛆病的研究及防治概况进行比较、分析，文章表述了①狂蝇幼虫的生态及流行状况远比以前的记载复杂，特别在宁夏地区狂蝇蛆在一年四季羊体内有不同发育期的幼虫同时寄生；②初步证明伊维菌索是防治本病的首选药物。     

内蒙古兴安盟羊狂蝇蛆病病原流行病学与季节动态研究

1999年3月～2000年2月,对来自内蒙古兴安盟牧区、半农半牧区和农区的5个旗县市22个乡(苏木、镇)的216只羊进行了尸体剖检,共收集羊狂蝇1、2、3龄幼虫3926个;对3群552只羊进行了临床检查。结果表明:羊狂蝇(Oestrus ovis)蛆是引起兴安盟羊狂蝇蛆病的病原;临床检查,羊狂蝇蛆病感染率为92.21％;尸体剖检,羊狂蝇各龄幼虫在羊鼻腔内全年至少寄生8个月。由于重复感染各龄幼虫感染率随季节不同而不同,范围在40.00～95.00％之间,感染强度为1～140个;动态监测,羊狂蝇1、2、3龄幼虫全年均表现出两个感染高峰,分别为6月和11月、5月和翌年1月、5月和8月,从而说明兴安盟羊狂蝇繁殖有两个世代。     

羊狂蝇幼虫药物防治试验及最佳防治时间的选择

本文依据对我省黄河谷地的贵德县和高原腹地的玉树县两个不同海拔、气候地区羊狂蝇成蝇出现及消失时间等活动规律的观察结果,选用阿维菌素和伊维菌素药物的不同剂型,分别在9月上旬和10月中旬选择自然感染羊狂蝇幼虫的绵羊200只;采用注射液口服、泼背和片剂口服的方法,对羊狂蝇幼虫进行药物驱除的效果比较试验。结果表明:9月上旬驱虫组效果达100%,而10月份驱虫组效果不理想。     

内蒙古洪安盟羊狂蝇蛆病病原流行病学与季节动态研究

1999年3月～2000年2月，对来自内蒙古兴安盟牧区、半农半牧区和农区的5个旗县市22个乡（苏木、镇)的216只羊进行了尸体剖检，共收集羊狂蝇1、2、3龄幼虫3926个；对3群552只羊进行了临床检查。结果表明：羊狂蝇（oestrus ovis)蛆是引起兴安盟羊狂蝇蛆病的病原；临床检查，羊狂蝇蛆病感染率为92．21％；尸体剖检，羊狂蝇各龄幼虫在羊鼻腔内全年至少寄生8个月。由于重复感染各龄幼虫感染率随季节不同而不同，范围在40．00～95．00％之间，感染强度为1～140个；动态监测，羊狂蝇1、2、3龄幼虫全年均表现出两个感染高峰，分别为6月和11月、5月和翌年1月、5月和8月，从而说明兴安盟羊狂蝇繁殖有两个世代。     

赤峰地区羊狂蝇蛆病流行规律与防治研究

羊狂蝇蛆病(Oestriasis)是由双翅目、狂蝇科、狂蝇属的羊狂蝇(Oestrus ovis)的幼虫寄生在羊的鼻腔及其附近的腔窦内引起的慢性鼻炎症状的寄生虫病。本病在世界上分布广泛,蒙古、前苏联、印度、美国等18个国家均有报道,在我国西北、内蒙古、华北及东北等地区较为常见。赤峰地区羊狂蝇蛆病流行时间久、分布普遍,是引起羊只死亡的主要寄生虫病     

驯鹿狂蝇幼虫感染情况调查

2003年3～9月，以内蒙古自治区根河市敖鲁古雅鄂温克民族乡作为试验基地，对829只驯鹿进行了鹿狂蝇幼虫感染率、感染强度和寄生部位的调查。结果表明，当地驯鹿狂蝇幼虫感染率为92．0％，平均感染强度为16．2条；驯鹿狂蝇幼虫主要寄生于驯鹿的鼻腔鼻甲部、咽喉部及鼻、咽的交接部。     

高原羊狂蝇成蝇飞翔规律的观察及防治时间的确定

本文对我省黄河谷地的贵德县和高原腹地的玉树县两个不同海拔、气候地区对羊狂蝇成蝇出现及消失的时间进行了观察,结果表明:青海高原不同海拔地区羊鼻蝇飞翔(产虫)期均在每年的7月中下旬,差别只是较寒冷的高海拔地区产卵期出现较晚。依据这一成蝇飞翔产虫的活动规律,我们认为9月上旬是驱虫防治的最佳期。     

Genetic structure of Oestrus ovis populations in sheep and goats.

A genetic analysis using RAPD markers was performed on 12 natural populations of Oestrus ovis (Linné, 1761). Three-hundred and six O. ovis larvae (first, second and third instars) were randomly recovered in nasal cavities of sheep and goats naturally infected in Algeria, Ethiopia, France, Mauritania, Rumania and Tunisia and were analysed by 56 RAPD fragments. The results showed a high diversity within all samples. A significant genetic divergence was showed by discriminant analyses among the 12 populations sampled (p<0.0001). Moreover, discriminant analyses showed significant differentiation (p<0.0001) between O. ovis larva populations of sheep and goats and also among samples collected in the same region.     

Analysis of the humoral immune response to Oestrus ovis in ovine

Antibody responses (IgG, IgM and IgA) against Oestrus ovis were analyzed in sheep and in first year grazing lambs from Sardinia (Italy) by an indirect-enzyme-linked immunoassay test and L2 O. ovis excretory/secretory antigens. Serum samples from 208 sheep were obtained prior to be slaughtered, and then heads were removed and cut open along their longitudinal axis to collect the parasites from the nasal cavities, turbinates and sinus. Besides this, blood samples were monthly collected from the lambs of G-1 (maintained under field conditions) and the lambs of G-2 (kept housed since birth to avoid Oestrus infestations) throughout a year. In the sheep, a positive significant correlation was observed between the number of first instar O. ovis larvae and the values of IgM, and between the second instar larvae and the IgG optical densities. In the lambs, all classes of antibodies increased significantly from July in G-1. The highest values of IgG were reached in September (IgG) and decreased in November-December. The IgM response peaked in November, and very low values of IgA were observed during the study. Matching these data with chronobiology of O. ovis in this region, we conclude that the first infection occurs on May, stimulating the production of humoral antibodies. The reduction of the IgG antibody levels starting from October means the beginning of the diapause while the IgM response seems to be associated to the presence of L1 in the nasal cavities. The data obtained led us to forecast an early treatment of the ovine on June-July, which should keep away from the maturation of O. ovis L1 larvae, avoiding the development of clinical lesions and interrupting the life cycle of this parasite.     

Cellular and humoral local immune responses in sheep experimentally infected with Oestrus ovis (Diptera: Oestridae)

Cellular and humoral local responses were investigated following repetitive artificial Oestrus ovis infections in lambs. The presence of larvae induced a huge local recruitment of either leucocytes (T and B lymphocytes, macrophages) or granulocytes (eosinophils, mast cells and globule leucocytes). This cellular response was more pronounced in the ethmoid and sinus (development sites of second and third instar larvae) than in the septum or turbinates where first instar larvae migrate. Infected lambs produced Oestrus ovis specific IgG and IgA antibodies in their mucus. This local humoral response was mainly directed against larval salivary gland antigens and not against larval digestive tract antigens. Compared to the control animals, the sinusal mucosa of infected animals was extremely thickened and the epithelium exhibited hyperplasia, metaplasia and eosinophilic exocytosis. The possible roles of these local immune responses in the regulation of O. ovis larvae populations in sheep are discussed.     

云南省楚雄州部分地区猪瘟血清学调查

为了解楚雄州部分地区的猪瘟免疫情况,利用酶联免疫法（ELISA）对楚雄市、南华县和禄丰县随机采取的393份血清进行猪瘟抗体检测,并对各县（市）的调查数据加以比较,了解猪瘟在楚雄州部分地区的免疫情况。结果显示,楚雄州部分地区均有较高的猪瘟抗体阳性率,各县（市）的猪瘟抗体阳性率都在80％以上,有的县（市）猪瘟抗体甚至达到了100％。说明楚雄州部分地区的猪瘟免疫效果较好,猪瘟免疫成功。     

Oestriasis in small ruminants in Senegal. Preliminary note

Observations made in Dakar abattoirs from March to December 1987 revealed that 46.39 per cent sheep and 57.89 per cent goats carried Oestrus ovis larvae. A clear relationship between cause and effect exists between nasal discharge and the presence of mature larvae. Because of their spine covering, they are irritating enough to provoke nasal mucosa inflammation with possible microbic complications. It is thus necessary to take into account the frequency and the pathogenicity of Oestrus ovis infection in the aetiologic study of respiratory affections of the small ruminants in Senegal.     

Seroprevalence of Oestrus ovis infection in sheep in southwestern Germany

The aim of the survey was to determine the seroprevalence of Oestrus ovis infection in flocks in southwestern Germany. Serum samples collected from 1497 sheep (>6 months of age) of 110 flocks in 1997 and 1998 were examined for antibodies to crude somatic antigens of O. ovis second-stage larvae using an ELISA test. Data on the farm management were obtained by a questionnaire. Overall, 76% of the flocks had at least one seropositive animal, and the seroprevalence of anti-Oestrus antibodies was 50% in sheep. Flock size was the only risk factor significantly associated with the detection of antibodies. Larger flocks (>50 ewes) were more likely to be seropositive than smaller ones. These results show that Oestrus infections are widespread in sheep in southwestern Germany. Further investigations are required to estimate the economic importance of oestrosis and the efficiency of control measures.     

Efficacy of ivermectin controlled-release capsules for the control and prevention of nasal bot infestations in sheep

Objective To investigate the therapeutic and prophylactic efficacy of an ivermectin controlled-release capsule against nasal bots (Oestrus ovis) in sheep.
Design Trial 1 – A pen study with controls. Trial 2 – A field study with controls.
Animals Trial 1 – Forty Merino wethers with natural infestations of nasal bot were used. Trial 2 – One hundred nasal bot-free wethers were used.
Procedure Trial 1 – Ten randomly selected animals were slaughtered and the heads split and examined to confirm bot infestation. Fifteen animals were allocated to untreated controls and 15 to treatment with a controlled-release capsule delivering ivermectin at ≥ 20 μg/kg/day for 100 days. Twenty-nine days after treatment the sheep were killed and examined for nasal bots. Trial 2 – Nasal bot-free sheep were allocated to two groups of 45 animals. One group was untreated the other sheep were treated with capsules as above. The sheep were grazed as a single group exposed to natural challenge from O ovis . Ninety days after treatment the animals were slaughtered and examined for nasal bot infestation.
Results Trial 1 – Live O ovis larvae were recovered from 60% of control sheep. No live larvae were collected from treated sheep. Trial 2 – Forty-one percent of untreated sheep harbored nasal bot infestations. No live larvae were collected from any treated animal.
Conclusion Treatment with a single ivermectin controlled-release capsule was 100% effective against existing infestations of O ovis and as a prophylactic treatment for this parasite.     

Changing reactivity of caprine and ovine mononuclear phagocytes throughout part of the life cycle of Oestrus ovis: assessment through spontaneous and inductible NO production.

The in vitro reactivity of monocyte-derived macrophages (MDM) from Oestrus ovis (O. ovis) artificially infested lambs and kids was determined by measuring their production of nitric oxide (NO) during the course of infestation. In both species, crude antigenic preparations obtained from O. ovis first instar larvae (L1) were found to significantly (P < 0.01) inhibit this NO production, whereas O. ovis second instar (L2) extract stimulated it. Furthermore, this NO production by MDM decreased during infestation and was related to blood eosinophilia. It appears that crude antigenic extract from O. ovis modified the NO activity of macrophages from lambs and kids infested with O. ovis larvae.     

伊维菌素控制春乏期羊狂蝇蛆病试验

目的为有效预防和控制羊狂蝇蛆病的发生。方法选用伊维菌素在羊狂蝇成虫完全消失的11月进行驱杀羊狂蝇蛆试验,并以敌敌畏熏蒸作为对照。结果在来年羊狂蝇成蝇出现之前的长达7个月的冬春枯草季节,伊维菌素组驱虫率和驱净率均保持100％,而敌敌畏熏蒸组驱虫率保持94．69％,驱净率仅保持60％。结论选择每年11月份用伊维菌素驱虫一次,可使羊在冬春季节无任何阶段羊狂蝇幼虫寄生。