title: The urticating setae of Ochrogaster lunifer, an Australian processionary caterpillar of veterinary importance.
abstract: The bag-shelter moth, Ochrogaster lunifer Herrich-Schaffer (Lepidoptera: Notodontidae), is associated with a condition called equine amnionitis and fetal loss (EAFL) on horse farms in Australia. Setal fragments from O. lunifer larvae have been identified in the placentas of experimentally aborted fetuses and their dams, and in clinical abortions. The gregarious larvae build silken nests in which large numbers cohabit over spring, summer and autumn. The final instars disperse to pupation sites in the ground where they overwinter. Field-collected O. lunifer larvae, their nests and nearby soil were examined using light and electron microscopy to identify setae likely to cause EAFL and to determine where and how many were present. Microtrichia, barbed hairs and true setae were found on the exoskeletons of the larvae. True setae matching the majority of setal fragments described from equine tissue were found on third to eighth instar larvae or exuviae. The number of true setae increased with the age of the larva; eighth instars carried around 2.0-2.5 million true setae. The exuvia of the pre-pupal instar was incorporated into the pupal chamber. The major sources of setae are likely to be nests, dispersing pre-pupal larvae and their exuviae, and pupal chambers.
authors.affiliation: School of Biological Science, The University of Queensland, Brisbane, Queensland, Australia.
authors.forename: L E
authors.identifier: 0000-0002-2098-1112
authors.initials: LE
authors.lastname: Perkins
authors.affiliation: School of Biological Science, The University of Queensland, Brisbane, Queensland, Australia.
authors.forename: M P
authors.initials: MP
authors.lastname: Zalucki
authors.affiliation: AusVet Animal Health Services, Toowoomba, Queensland, Australia.|Equine Research Unit, School of Agriculture and Food Sciences, The University of Queensland, Gatton, Queensland, Australia.
authors.forename: N R
authors.initials: NR
authors.lastname: Perkins
authors.affiliation: Equine Research Unit, School of Agriculture and Food Sciences, The University of Queensland, Gatton, Queensland, Australia.
authors.forename: A J
authors.initials: AJ
authors.lastname: Cawdell-Smith
authors.affiliation: Vetnostics, North Ryde, New South Wales, Australia.
authors.forename: K H
authors.initials: KH
authors.lastname: Todhunter
authors.affiliation: Equine Research Unit, School of Agriculture and Food Sciences, The University of Queensland, Gatton, Queensland, Australia.
authors.forename: W L
authors.initials: WL
authors.lastname: Bryden
authors.affiliation: School of Biological Science, The University of Queensland, Brisbane, Queensland, Australia.|Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, Queensland, Australia.
authors.forename: B W
authors.initials: BW
authors.lastname: Cribb
mesh_terms: D000818:Animals; D002821:Chorioamnionitis / Q000209:etiology / Q000662:veterinary*; D005260:Female; D006734:Horse Diseases / Q000209:etiology*; D006736:Horses; D007814:Larva / Q000033:anatomy & histology / Q000254:growth & development / Q000502:physiology; D009036:Moths / Q000033:anatomy & histology* / Q000254:growth & development / Q000502:physiology*; D009517:New South Wales; D011247:Pregnancy; D011679:Pupa / Q000033:anatomy & histology / Q000254:growth & development / Q000502:physiology; D011793:Queensland; D058618:Sensilla / Q000502:physiology; D014739:Victoria
keywords: Lepidoptera; Notodontidae; Thaumetopoeidae; bag-shelter moth; equine amnionitis and fetal loss (EAFL); true setae