虫克星驱治猪蛔虫效果试验

虫克星驱治猪蛔虫效果试验林伟文卢文规北流市兽医站５３７４００中图分类号：Ｓ８５８２８０５９虫克星是中国农业大学最近研制的高新科技产品，是目前较为理想的高效、广谱、低毒的驱虫新药。为验证该药在本地区的驱虫效果，以便推广使用提供依据，于１９９５年９月...     

虫克星对猪蛔虫的驱虫效果试验

虫克星（Averbau）是国产阿维菌素（Aver－mectinB1）的商品名称。据。北农快讯》介绍,虫克星是广谱、高效、用量小,对人畜安全、被视为国内外最佳抗寄生虫新药。目前本地刚开始使用,为了验证虫克星对猪蛔虫的驱虫效果,更好地在实践中应用,特做此试验。1材料与方法1．1试验药物：虫克星片剂（5mg／片）由全国农业新技术产品传播网办公室提供（晋兽分字[96]×052300）;对照药物,盐酸主旋咪唑片剂（25kg／片）由萧山第二兽药厂提供（浙兽药字[95]×004009）。1．2试验地点：从宁国市中溪镇养殖场,提供的298头仔猪中,通过粪检,挑出…     

氟苯哒唑对猪蛔虫和猪鞭虫的驱虫效果

氟苯哒唑(Flubelldazole)是比利时杨森制药公司(Janssen Pharmaceutica)生产的一种广谱驱虫药,它已广泛地用于驱除人的线虫(Danis等,1980,Becquet和Labarriere,1980);也已普遍地用于驱除禽的线虫和绦虫(Froyman和De Key-     

阿弗米丁、左旋咪唑擦剂对猪蛔虫的驱除效果

阿弗米丁、左旋咪唑擦剂对猪蛔虫的驱除效果王文福符文英（执笔）李延章，李黎，白玉轮，郭仁民（互助县畜牧兽医站，８１０５００）（青海省畜牧兽医总站）寄生虫病是妨碍猪只生长的主要疾病。据互助县１９８９～１９９０年调查，猪寄生虫危害以猪蛔虫、圆形似蛔线虫等肠...     

Immunity of swine to Ascaris suum

Swine were hyperimmunized to Ascaris suum by giving multiple oral inoculations of embryonated eggs. Sera and lymphocyte lysate from these pigs were administered parenterally to 4-week-old pigs. The latter animals were no more resistant to larval migration than control pigs receiving sera or lymphocyte lysate from non-immunized pigs. Other pigs were infected with transmissible gastroenteritis (TGE) virus, allowed to recover and challenged with embryonated ascarid eggs. They likewise were no more resistant to ascarid larval migration than control pigs.     

Reinfection of Yearling Calves with Ascaris suum

Naturally occuring outbreaks of Ascaris suum infection in calves have usually beeen found in animals nine to 12 months of age. The circumstances surrounding these outbreaks suggest that yearling calves are either particularly susceptible to a primary exposure to A. suum or react strongly to A. summ after sensitization early in life to this or some related ascarid. To determine the effect of reinfection with A. suum nine to 12 months after varying levels of exposure to this nematode, six calves were inoculated with 200,000 to 9,000,000 eggs. Neither death nor, in general, severe clinical signs resulted from reinfection. All calves were examined 15 days after reinfection with pathological changes noted only in the lungs and consisting of emphysema, alveolar wall thickening as well as accumulations of fibrin, eosinophils and hemorrhage in the lumina of alveoli. The findings suggested that exposure to A. suum early in life is not a factor in the development of disease in calves infected at one year of age. It was also found that the eosinophilia that develops following a primary infection with A. suum evidently persists for at least one year.     

Mature Ascaris suum in naturally infected calves

In two small farms in Sweden young calves were found to be naturally infected with Ascaris suum. One of the calves expelled mature worms with the faeces, one had a great number of worms in the ductus choledochus and two others had worms in the intestine. Most of the worms were mature and at the egg-producing stage. The morphology of the eggs and the adult worms indicated that these parasites were A. suum and that Toxocara (syn. Neoascaris) vitulorum could be excluded.     

The development of Ascaris suum in calves.

To determine the development of Ascaris suum after a primary and a secondary infection, 18 calves were inoculated with 2,000,000 infective eggs and examined from 18 hours to 13 days postinfection. At 18 hours larvae were recovered from the wall of the abomasum, duodenum and jejunum. They were found in small intestine lymph nodes on the third day, in the liver at five days and were most abundant in the lungs on days 7 and 9. The pattern of recovery of larvae from the lung between days 5 and 13 postinfection was similar after a primary or a secondary infection. Slower growth of larvae following a secondary infection was the only evidence of resistance to A. suum. There were no pathological changes observed in the alimentary canal. White foci were found on the surface of the liver as early as the third day. The rapid decline in the number of A. suum in the lungs after the ninth day was considered to be related to immobilization or death of larvae soon after the reaction to them commences.     

Seminal vesicle growth induced by Ascaris suum infection

This study was designed to determine the effect of Ascaris suum infection upon growth of mouse vesicular glands. Mice were infected with varying dosages of A. suum eggs and killed after six weeks. Results indicated a dose dependent increase in seminal vesicle weight, independent of total body weight.     

Ascaris suum Infection in Calves III. Pathology

Gross changes in the lungs of Ascaris suum- infected calves consisted of atelectasis and hemorrhagic foci, edema and emphysema, frequently with bullae. Prominent microscopic lung lesions were edema and emphysema of the interlobular septa with large numbers of eosinophils within and around lymphatics, peribronchiolar lymphoid nodules and parasitic granulomas. Many of the microscopic features were consistent with those found in atypical interstitial pneumonia. Changes in the alveoli were atelectasis, the exudation of plasma proteins, mononuclear cells and eosinophils, and alveolar wall thickening. Lesions found later included fibrosis and fetalization of the alveolar walls. Plasma cells and neutrophils were not common. Challenge with Toxocara canis after sensitization with A. suum resulted in the lungs developing a few areas of atelectasis. Migration of T. canis to lungs of calves is slower than A. suum. A. suum larvae were always found in bronchi, bronchioles and alveoli of calves that died. Lesions were observed in the liver but not the kidney of A. suum infected calves; both lung and liver lesions tended to resolve with time.     

Screen for anthelmintics, using larvae of Ascaris suum

A multiwell culture system was used to assay the effects of 12 known anthelmintic compounds on Ascaris suum larval development from 2nd-stage (L2; hatched from eggs) to early 3rd-stage (L3) and from in vivo-derived late L3 to early 4th-stage (L4). Larval survival, development, and motility were monitored for drug effects. Development of L2 to L3 was sensitive to thiabendazole, albendazole (ABZ), ABZ/sulfoxide, ABZ/sulfone (SO), mebendazole, L-tetramisole, D-tetramisole, piperazine, or closantel at a concentration of 0.01 microgram/ml; however, the effects of these drugs on larval development did not correlate well with known effects in vivo. The development of L3 to L4 was blocked by ABZ or mebendazole at 0.01 microgram/ml, by thiabendazole or ABZ/sulfoxide at 0.1 microgram/ml, and by ABZ/SO at 1.0 microgram/ml; however, except for ABZ/SO, most larvae were viable at these concentrations. In contrast, L-tetramisole or morantel appeared to inhibit development of L3 to L4 and to reduce survival at concentrations of greater than or equal to 1 microgram/ml; however, D-tetramisole was at least 10 times less effective. Haloxon, ivermectin, and closantel blocked development of L3 to L4 at 0.1, 1, and 10 micrograms/ml, respectively, in the absence of serum, but their activity was reduced by the presence of serum. Seemingly, in vitro development of A suum larvae was a convenient and sensitive bioassay for anthelmintic activity and could serve as a screen for anthelmintic residues in edible tissues.