---
OA_place: publisher
_id: '1395'
abstract:
- lang: eng
  text: In this thesis I studied various individual and social immune defences employed
    by the invasive garden ant Lasius neglectus mostly against entomopathogenic fungi.  The
    first two chapters of this thesis address the phenomenon of 'social immunisation'.
    Social immunisation, that is the immunological protection of group members due
    to social contact to a pathogen-exposed nestmate, has been described in various
    social insect species against different types of pathogens. However, in the case
    of entomopathogenic fungi it has, so far, only been demonstrated that social immunisation
    exists at all. Its underlying mechanisms r any other properties were, however,
    unknown. In the first chapter of this thesis I identified the mechanistic basis
    of social immunisation in L. neglectus against the entomopathogenous fungus Metarhizium.
    I could show that nestmates of a pathogen-exposed individual contract low-level
    infections due to social interactions. These low-level infections are, however,
    non-lethal and cause an active stimulation of the immune system, which protects
    the nestmates upon subsequent pathogen encounters. In the second chapter of this
    thesis I investigated the specificity and colony level effects of social immunisation.
    I demonstrated that the protection conferred by social immunisation is highly
    specific, protecting ants only against the same pathogen strain. In addition,
    depending on the respective context, social immunisation may even cause fitness
    costs. I further showed that social immunisation crucially affects sanitary behaviour
    and disease dynamics within ant groups. In the third chapter of this thesis I
    studied the effects of the ectosymbiotic fungus Laboulbenia formicarum on its
    host L. neglectus. Although Laboulbeniales are the largest order of insect-parasitic
    fungi, research concerning host fitness consequence is sparse. I showed that highly
    Laboulbenia-infected ants sustain fitness costs under resource limitation, however,
    gain fitness benefits when exposed to an entomopathogenus fungus. These effects
    are probably cause by a prophylactic upregulation of behavioural as well as physiological
    immune defences in highly infected ants.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Matthias
  full_name: Konrad, Matthias
  id: 46528076-F248-11E8-B48F-1D18A9856A87
  last_name: Konrad
citation:
  ama: 'Konrad M. Immune defences in ants: Effects of social immunisation and a fungal
    ectosymbiont in the ant Lasius neglectus. 2014.'
  apa: 'Konrad, M. (2014). <i>Immune defences in ants: Effects of social immunisation
    and a fungal ectosymbiont in the ant Lasius neglectus</i>. Institute of Science
    and Technology Austria.'
  chicago: 'Konrad, Matthias. “Immune Defences in Ants: Effects of Social Immunisation
    and a Fungal Ectosymbiont in the Ant Lasius Neglectus.” Institute of Science and
    Technology Austria, 2014.'
  ieee: 'M. Konrad, “Immune defences in ants: Effects of social immunisation and a
    fungal ectosymbiont in the ant Lasius neglectus,” Institute of Science and Technology
    Austria, 2014.'
  ista: 'Konrad M. 2014. Immune defences in ants: Effects of social immunisation and
    a fungal ectosymbiont in the ant Lasius neglectus. Institute of Science and Technology
    Austria.'
  mla: 'Konrad, Matthias. <i>Immune Defences in Ants: Effects of Social Immunisation
    and a Fungal Ectosymbiont in the Ant Lasius Neglectus</i>. Institute of Science
    and Technology Austria, 2014.'
  short: 'M. Konrad, Immune Defences in Ants: Effects of Social Immunisation and a
    Fungal Ectosymbiont in the Ant Lasius Neglectus, Institute of Science and Technology
    Austria, 2014.'
corr_author: '1'
date_created: 2018-12-11T11:51:46Z
date_published: 2014-02-01T00:00:00Z
date_updated: 2026-04-09T14:27:01Z
day: '01'
degree_awarded: PhD
department:
- _id: SyCr
language:
- iso: eng
month: '02'
oa_version: None
page: '131'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '5814'
status: public
supervisor:
- first_name: Sylvia M
  full_name: Cremer, Sylvia M
  id: 2F64EC8C-F248-11E8-B48F-1D18A9856A87
  last_name: Cremer
  orcid: 0000-0002-2193-3868
title: 'Immune defences in ants: Effects of social immunisation and a fungal ectosymbiont
  in the ant Lasius neglectus'
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2014'
...