牛、山羊及鹿Setaria屬腦脊髓絲狀蟲症之幼蟲形態比較

Comparisons of Larvae Morphological Properties of Setaria spp. in the Cattle, Goat and Deer with Cerebrospinal Setariasis

董光中(Kwong-Chung Tung) ； 賴政宏(Cheng-Hung Lai) ； 鄭豐邦(Feng-Pang Cheng) ； 吳瑞得(Jui-Te Wu) ； 楊正雄(Chen-Hsiung Yang) ； 王俊秀(Jiunn-Shiow Wang)

《臺灣獸醫學雜誌》 28卷3期 (2002/09) Pp. 220-227

https://doi.org/10.7009/TVJ.200209.0220

摘要

台灣地區有三種Setaria屬腦脊髓絲狀蟲，分別寄生於牛、羊及鹿造成腦脊髓絲狀蟲症。本研究僅以光學顯微鏡觀察此三種Setaria屬幼蟲之形態並進而比較其異同，以期提供區別鑑定之用。自牛、羊及鹿之腦脊髓腔檢出之絲狀蟲經觀察鑑定，其結果為第四期幼蟲頭端皆呈鈍圓，具有2個齒狀突起，S. digitata與S. marshalli尾端呈球狀結節，而S. cervi尾端有三至四個突起物。因此，不易以頭端及尾端區分S. digitata與S. marshalli之第四期幼蟲，但可以尾端區分出S. cervi。S. digitata、S. marshalli與S. cervi之第五期雌幼蟲不易以尾端區分，需以頭端齒凸形態區分之。另外，可以頭端齒凸形態區分出S. cervi再以尾端乳狀突起對數區分S. digitata與S. marshalli之第五期雄幼蟲。組織切片觀察S. digitata與S. cervi之第四期蟲體並無明顯差異。而此三種幼蟲在顱腔及脊髓腔的形態經觀察比較後，可提供其他研究者發現僅有頭端或尾端或是多品種寄生時之蟲體鑑定參考用。

關鍵字

Setaria屬腦脊髓絲狀蟲 ； 幼蟲 ； Sefaria cervi ； Sefaria digitata ； Setaria marshalIi

並列摘要

Up to date, three different species of cerebrospinal setariasis (Setaria digitata, S. marshaIIi, S. cervi) have been reported in Taiwan area. Despite that these causative parasites are known residency in the cattle, goat or deer, their morphological significance has not been well defined. Techniques of light-microscopy were applied to distinguish the morphological differences of three Setaria species. Results showed the 4th stage larvae collected from cerebrospinal cavities of three animals species, have similar blunt/round head adherent with two odontoid-like processes . The tails of S. digitata and S. marshalli exhibited spherical nodules feature while three to four prominences on S. cervi were observed. As a result, morphological distinction between the 4th stage larvae of S. digitata and S. marshalli is not feasible but characterization of the 4th larvae of S. cervi is ready, on the basis tail significance. During 5th stage of larvae, the caudal differences in three parasites become distinguishable. Thus, the odontoid-like process located on the head end, play a key role to identify the differences. The 5th stage larva of S. cervi is screened out by the cranial odontoid-like process while S. digitata and S. marshalli are recognized by the amounts of teat-process pair located on the tail end. Histological study revealed no remarkable difference between the 4th stage larvae of S. digitata and S. cervi. Conclusively, the morphological data of Setaria resident in the cerebrospinal cavities is obtained. These data provide valuable larvae-identification criteria that can be utilized to diagnose multi-parasite infection and/or to distinguish Setaria even though merely larva head or tail residues are available.

並列關鍵字

Cerebrospinal setariasis ； Larvae ； Setaria cervi ； Setaria digitata ； Setaria marshalli