阿氏后圓猪肺线虫[Metastrongylusapri (Ebel,1777)]的发育及其中間宿主种类的研究

STUDIES ON THE DEVELOPMENT OF METASTRONGYLUS, APRI(EBEL, 1777) IN THE INTERMEDIATE HOST, WITH A CONSIDERATION OF THE SPECIES OF EARTHWORMS CONCERNED IN THE TRANSMISSION OF THE PARASITE.

一、引言阿氏后圓猪肺綫虫[Metastrongylus apri (Ebel,1777)]隶于后圆綫虫科(Metastrongylidae Leiper,1908)是世界性分布的种类,发現历史甚早,远在1777年Ebel氏即已描述,定名为Gordius apri,后来Schrank(1788),Modeer(1791),Rudolphi(1809),Mehlis(1831),Dujardin(1845)等学者在不同地区于家猪和野猪(Sus scrofa atilla, Sus scrofanigripes,Sus scrofa continentali)等体中,先后相继发現,訂定不同名称。1851年Diesing又报告一小孩寄生有这种綫虫的病例,Kox(1883)发現綿羊亦寄生有这种綫虫。

Metastrongylus apri (Ebel, 1777) occurs as widespread parasite of swine in Fukien. Of 900 pigs examined, 22.8% of them were found infected. Experiments were performed in the laboratory to infect local species of earthworms with succes. Descriptions of various Stages of this nematode, including its embryonic development were presented in the present article. The larvae of M. apri are ingested by the earthworm within its gullet, the parasite begins to develope and can penetrate into the stomach wall, or into the blood vessels. In the stomach wall the larvae grow and moult into the second stage larvae in about 4-5 days. The larve were also found in the wall of intestine below the stomach. They moult again in 8-9 days to become the third infective larvae. Swines get infected by swallowinge the earthworms, while feeding on the subterrarean plant stuffs.The author made field surveys in several districts, such as Hsiapu, Fuan and Putien along the coast of Eukien Province, where earthworms were collected and examined. From our infection experiments together with the finding of naturally infected earthworms, we gathered some important informations regarding the species, distribution and infective rate of the various species of earthworms actiug as the intermediate hosts.Eleven species of earthworms were experimentally infected in the laboratory, nine of them were found to be naturally infected in our field surveys. They are Pheretima hupeiensis (Michaelsen, 1895), Ph. californica Kinberg, 1867, Ph. hawayana (Rosa, 1891) Ph, morrisi (Eeddard, 1892), Ph. robusta (E. Perrier, 1872), Ph. aspergillum (E. Perrier, 1872) Bimastus parvus (Eisen, 1874), Allolophora caliginosa subsp. trapezoides (Ant. Duges. 1828) and Howascolex sp..Of the above mentioned, Ph. hupeiensis, Ph. robusta and Howascolex sp. are the three most important species. They serve as the important intermediate host of M. apri in this province.Two species of earthworms, which we experimeatally infected in our laboratory and which were not found naturally infected in our field surveys are: Ph. diffringens (Baird, 1896) and Ph. sp..All the nine species of earthworms are new hosts of M. aprt, heretofore not recorded in the literature.