The opening talk for my PhD defense "Longitudinal monitoring of parasites in individual wild primates"

1. Longitudinal monitoring
of parasites in individual
wild primates
20.11.2015
Lectio 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

3. IntroductionMethodsStudyI&IIStudyIIIStudyIVConclusion

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

4. IntroductionMethodsStudyI&IIStudyIIIStudyIVConclusion

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

5. Aims of the thesis
IntroductionMethodsStudyI&IIStudyIIIStudyIVConclusion
• Study intestinal parasite
community dynamics within-
host
• Design a new method for
identifying parasite
community composition

6. Rufous mouse lemur
Microcebus rufus
Hibernates
and torpors
Small-sized
Primate
Nocturnal
Territorial
Long-lived
IntroductionMethodsStudyI&IIStudyIIIStudyIVConclusion

7. 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
IntroductionMethodsStudyI&IIStudyIIIStudyIVConclusion

8. • Mark-recapture for 3 years
• 636 samples from 134 different individuals
IntroductionMethodsStudyI&IIStudyIIIStudyIVConclusion

9. IntroductionMethodsStudyI&IIStudyIIIStudyIVConclusion

10. The detection
pipeline
IntroductionMethodsStudyI&IIStudyIIIStudyIVConclusion

11. Séance
IntroductionMethodsStudyI&IIStudyIIIStudyIVConclusion

12. Method
• Success rate quite low: only 44% for mouse
lemurs
• Difficulties with fecal nematodes
• General problems with non-invasive
assessment
IntroductionMethodsStudyI&IIStudyIIIStudyIVConclusion

13. Between-host dynamics
IntroductionMethodsStudyI&IIStudyIIIStudyIVConclusion
Putative
species 1
Strongyloides Putative species 4 Chromadorea
Putative
species 2
Rhabditidae Putative species 5 Enterobius
Putative
species 3
Strongylida Putative species 6 Panagrellus

14. Within-host dynamics
IntroductionMethodsStudyI&IIStudyIIIStudyIVConclusion
First samples
without parasites
Rare species are
ephemeral
Also turnover in
common species

15. Mouse lemur body
condition and parasites
• Better body condition correlates with
– Higher ectoparasite counts
– Higher parasite richness
IntroductionMethodsStudyI&IIStudyIIIStudyIVConclusion
Model n r P
CRT index vs lice score 120 -0.19 0.04
CRT index vs nematode abundance 119 -0.00 0.98
CRT index vs cestode abundance 120 -0.14 0.13
CRT index vs parasite richness 120 -0.19 0.03
n = sample size, r = correlation coefficient of spearman, P = probability

16. 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
IntroductionMethodsStudyI&IIStudyIIIStudyIVConclusion

17. 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
IntroductionMethodsStudyI&IIStudyIIIStudyIVConclusion