玉山和柴山地區臺灣獼猴（Macaca cyclopis）腸道寄生蟲之比較

Abstract

自1994年9月至1995年11月，於玉山國家公園新中橫公路與高雄柴山兩地區，進行台灣獼猴之腸道寄生蟲相研究，本實驗目的在於（1）瞭解野外台灣獼猴體內寄生蟲的現況，以提供日後野外動物寄生蟲調查的方法及基本資料。（2）探討獼猴腸道寄生蟲感染狀況的季節性變化及兩族群間的差異，並由外界環境、猴群間交互作用、個體年齡及寄生蟲生活史等方向，討論造成兩地獼猴寄生蟲相差異的可能。 野外獼猴的腸道寄生蟲分析，由兩地各月採集一次新鮮猴糞，以10％福馬林溶液保存糞便中的寄生蟲卵，研究期間共分析了265個猴糞樣本，共計發現13種腸道寄生蟲，包括鞭蟲、腸結節蟲、福氏桿線蟲、毛圓線蟲、球翼圓線蟲、胃蟲、蟯蟲、蛔蟲、毛細線蟲、Ternidens等10種線蟲；大腸纖毛蟲與大腸阿米巴等2種原蟲及裸頭條蟲僅1種絛蟲。其中，福氏桿線蟲、蟯蟲、蛔蟲為本次實驗所發現的新記錄種。由兩地獼猴之各類寄生蟲的感染率、蟲卵排出量及感染強度比較：除了糞桿線蟲和蛔蟲外，玉山獼猴的各種寄生蟲的感染率較柴山者高，平均蟲卵排出量及感染強度皆較柴山者高。 鞭蟲、腸結節蟲及福氏桿線蟲三種是兩地獼猴主要感染的線蟲（感染率大於10％），三者感染率有明顯的季節變化，但兩地的月間變化不一致：玉山地區的感染率夏季較冬季大；柴山地區則是冬季較夏季大。由上述三種線蟲之平均蟲卵排出量及感染強度的季節性變化來看：鞭蟲的排卵量在一年中平均三個月為一個週期，而腸結節蟲及福氏桿線蟲在一年中僅有一次排卵高峰。氣溫對兩地獼猴之腸結節蟲、福氏桿線蟲感染率及蟲卵排出量有不同的影響，但影響的情形不同，玉山氣溫升高對寄生蟲的感染有利，而柴山則否。這可能與兩地海拔及氣溫上的差異有關。 由個體蟲卵排出量的變異程度分析，兩地的四種常見寄生蟲的蟲卵（或原蟲）皆呈聚集分佈。個體年齡和猴群間的交流，皆是影響寄生蟲群聚的因素之一：大、中、幼猴的寄生蟲種類數相近，但組成上以中、小猴間較相近，大猴與上兩類個體間的差異較大。另外，不同猴群的寄生蟲相有差異，鞭蟲在各群間感染率和蟲卵排出量都有顯著差異，相鄰猴群間寄生蟲群集的相異度越小，可能與鄰近群獼猴的活動範圍重疊有關。 由高低溫度下幼蟲的培養實驗發現，桿線蟲的桿狀幼蟲在25℃下的孵出時間較快，另外25℃下具感染性的絲狀幼蟲數量亦多。而腸結節蟲幼蟲則在37℃下的孵出時間較快。兩種線蟲對溫度的不同反應，可能由於兩者生活史上的差異。而此結果可能與本研究所觀察到柴山與玉山兩地間寄生蟲感染狀況上之差異有關。

A total of 265 feces of wild Taiwan macaque (Macaca cyclopis) were collected at Yu-shan National Park and Chai-shan (KaoShung) from September 1994 to November 1995. Fecal specimens preserved in 10% formalin were examined for the presence and the amount of helminth ova and protozoa cyst. Ten intestinal nematodes, one cestode and two protozoa were found. Trichuris trichiura, Oesophagostonum sp. and Strongyloides fuelleborni were the most prevalent nematode parasites for the monkeys in the two areas. Yu-shan monkeys had higher prevalence and egg abundance for most parasite species than Chai-shan monkeys, except for Strongyloides fuelleborni and Ascaris sp. Nematode infection followed a different seasonal pattern in the two areas. In Yu-shan, Trichuris trichiura, Oesophagostonum sp. and Strongyloides fuelleborni were more prevalent during hot seasons than in cold seasons. The pattern for those parasites in Chai-shan was the opposite. The prevalence of these three parasite species were positively correlated with the monthly mean temperature in Yu-shan, but were negatively correlated in Chai-shan. This suggests that parasite infection might be influenced by temperature or other environmental factors. Monkeys of different body size and different troops have different parasite infection. The parasite species found in small monkeys are similar to those found in medium-sized ones, while the parasites found in large monkeys are different from the others. Significant difference in the prevalence and egg abundance of Trichuris trichiura was found among different troops in Yu-shan. The dissimilarity indices of the parasite community were lower for neighboring troops which may be explained by their overlapping ranges and similar habitats. The larval culture experiments showed the response of Oesophagostonum sp. and Strongyloides fuelluborni larvae to the two culture temperatures (25℃ and 37℃) were different. The observed pattern might be related to the difference in the life cycles of the two species.