Chapman Colin A, Speirs Michaela L, Gillespie Thomas R, Holland Timothy, Austad Kiersten M
Anthropology Department and McGill School of Environment, McGill University, Montreal, Canada.
Am J Primatol. 2006 Apr;68(4):397-409. doi: 10.1002/ajp.20233.
Humans are responsible for massive changes to primate habitats, and one unanticipated consequence of these alterations may be changes in host-parasite interactions. Edges are a ubiquitous aspect of human disturbance to forest landscapes. Here we examine how changes associated with the creation of edges in Kibale National Park, Uganda, alter the parasite community that is supported by two species of African colobines: the endangered red colobus (Piliocolobus tephrosceles) and the black-and-white colobus (Colobus guereza). An analysis of 822 fecal samples from edge and forest interior groups revealed no difference in the richness of parasite communities (i.e., the number of parasite species recovered from the host's fecal sample). However, for both species the proportion of individuals with multiple infections was greater in edge than forest interior groups. The prevalence of specific parasites also varied between edge and forest interior groups. Oesophagostomum sp., a potentially deleterious parasite, was 7.4 times more prevalent in red colobus on the edge than in those in the forest interior, and Entamoeba coli was four times more prevalent in red colobus on the edge than in animals from the forest interior. Environmental contamination with parasites (measured as parasite eggs/gm feces) by red colobus from the edge and forest interior differed in a similar fashion to prevalence for red colobus, but it did not differ for black-and-white colobus. For example, egg counts of Oesophagostomum sp. were 10 times higher in red colobus from the edge than in those from the interior. The less severe infections in the black-and-white colobus relative to the red colobus may reflect the fact that black-and-white colobus raid agricultural crops while red colobus do not. This nutritional gain may facilitate a more effective immune response to parasites by the black-and-white colobus. The fact that animals on the edge are likely not nutritionally stressed raises an intriguing question as to what facilitates the elevated infections in edge animals. We speculate that interactions with humans may be linked to the observed patterns of infections, and hence that understanding the ecology of infectious diseases in nonhuman primates is of paramount importance for conservation and potentially for human-health planning.
人类对灵长类动物栖息地造成了巨大改变，而这些改变带来的一个意想不到的后果可能是宿主与寄生虫相互作用的变化。边缘地带是人类对森林景观干扰的一个普遍存在的方面。在这里，我们研究了乌干达基巴莱国家公园中与边缘地带形成相关的变化如何改变由两种非洲疣猴所支持的寄生虫群落，这两种疣猴分别是濒危的红疣猴（Piliocolobus tephrosceles）和黑白疣猴（Colobus guereza）。对来自边缘地带和森林内部群体的822份粪便样本的分析表明，寄生虫群落的丰富度（即从宿主粪便样本中检测到的寄生虫物种数量）没有差异。然而，对于这两个物种来说，多重感染个体的比例在边缘地带群体中比在森林内部群体中更高。特定寄生虫的流行率在边缘地带和森林内部群体之间也有所不同。食口线虫属（Oesophagostomum sp.）是一种潜在有害的寄生虫，在边缘地带的红疣猴中其流行率比森林内部的红疣猴高7.4倍，而结肠内阿米巴（Entamoeba coli）在边缘地带的红疣猴中的流行率是森林内部红疣猴的四倍。边缘地带和森林内部的红疣猴对寄生虫的环境污染（以每克粪便中的寄生虫卵数衡量）与红疣猴的流行率变化方式相似，但黑白疣猴的情况并非如此。例如，边缘地带红疣猴的食口线虫属虫卵计数比内部的高10倍。相对于红疣猴，黑白疣猴感染较轻可能反映了这样一个事实，即黑白疣猴会掠夺农作物而红疣猴不会。这种营养获取可能有助于黑白疣猴对寄生虫产生更有效的免疫反应。边缘地带的动物可能没有营养压力这一事实引发了一个有趣的问题，即是什么导致了边缘地带动物感染率升高。我们推测与人类的相互作用可能与观察到的感染模式有关，因此了解非人类灵长类动物传染病的生态学对于保护以及潜在的人类健康规划至关重要。
