Longitudinal monitoring of parasites in individual

wild primates

20.11.2015Lectio praecursoria

Tuomas Aivelo (@aivelo)

Institute of Biotechnology; Department of Biosciences, Faculty of Biological and Environmental Sciences and Doctoral Programme in Wildlife Biology,University of Helsinki

Introduction M

ethods Study I &

II Study III

Study IV Conclusion

Host individual is a dynamic habitat

How parasite communities change?

Understanding interactions in parasite communities

→ virulence, prevalence etc.→ resistance, tolerance

Succession in parasite communities

→ host development

Introduction M

ethods Study I &

II Study III

Study IV Conclusion

Focus on component populations (= one parasite species in a host community)

Infrapopulations (= one parasite species in a single host) rarely studied

Focus often on single species / taxons

Aims of the thesisIntroduction

Methods

Study I & II

Study III Study IV

Conclusion

• Study intestinal parasite community dynamics within-host

• Design a new method for identifying parasite community composition

Rufous mouse lemurMicrocebus rufus

Hibernates and torpors

Small-sized

Primate

Nocturnal

Territorial

Long-lived

Introduction M

ethods Study I &

II Study III

Study IV Conclusion

Ranomafana National Park

• Southeastern Madagascar • Two transects

– Talatakely: inside park, heavy tourist load, secondary forest

– Campsite: in peripheral zone, degraded habitat, frequented by locals and students

Introduction M

ethods Study I &

II Study III

Study IV Conclusion

• Mark-recapture for 3 years• 636 samples from 134 different individuals

Introduction M

ethods Study I &

II Study III

Study IV Conclusion

Introduction M

ethods Study I &

II Study III

Study IV Conclusion

The detection pipeline

Introduction M

ethods Study I &

II Study III

Study IV Conclusion

SéanceIntroduction

Methods

Study I & II

Study III Study IV

Conclusion

Method

• Success rate quite low: only 44% for mouse lemurs

• Difficulties with fecal nematodes• General problems with non-invasive

assessment

Introduction M

ethods Study I &

II Study III

Study IV Conclusion

Between-host dynamicsIntroduction

Methods

Study I & II

Study III Study IV

Conclusion

Putative species 1

Strongyloides Putative species 4 Chromadorea

Putative species 2

Rhabditidae Putative species 5 Enterobius

Putative species 3

Strongylida Putative species 6 Panagrellus

Within-host dynamics

Introduction M

ethods Study I &

II Study III

Study IV Conclusion

First samples without parasites

Rare species are ephemeral

Also turnover in common species

Mouse lemur body condition and parasites

• Better body condition correlates with– Higher ectoparasite counts– Higher parasite richness

Introduction M

ethods Study I &

II Study III

Study IV Conclusion

Model n r PCRT index vs lice score 120 -0.19 0.04

CRT index vs nematode abundance 119 -0.00 0.98CRT index vs cestode abundance 120 -0.14 0.13CRT index vs parasite richness 120 -0.19 0.03n = sample size, r = correlation coefficient of spearman, P = probability

In nutshell

• While parasite communitiess seem stable looking at host at population-level sampling, individual monitoring can reveal wildly dynamic parasite community

• High-throughtput identification of intestinal nematodes is difficult but possible

Introduction M

ethods Study I &

II Study III

Study IV Conclusion

Future directions

• Interaction of parasites and microbiome

• Possibilities to track the most common nematode:– Do they die during hibernation?– Is there population structure in

parasites? • Parasite identification straight

from feces

Introduction M

ethods Study I &

II Study III

Study IV Conclusion