Observations on the transmission and development of Toxocara pteropodis (Ascaridoidea: Nematoda) in the Australian grey-headed flying-fox, Pteropus poliocephalus (Pteropodidae: Megachiroptera).

Abstract

Findings in the Australian Grey-Headed Flying-Fox, Pteropus poliocephalus, have elucidated the life-cycle of Toxocara pteropodis. In adult bats, other than parturient females, larvae were found only in the livers. Following parturition, larvae were recovered only from mammary glands up to 2 weeks post-partum. Developing larvae were found only in the intestine of young bats from the age of two days onwards; there was no evidence of pulmonary migration. The evidence indicates that juvenile bats commence passing Toxocara eggs in their faeces at about 2 months of age and expel the worms spontaneously following weaning at about 5 months. The eggs passed in the faeces of the young bat and its mother are disseminated throughout their environment and embryonate rapidly, being infective to mice after 10 days. Under natural conditions the eggs remain viable for 6 weeks or less and are infective to bats by the oral route.