Autogenicity and Precocious Development of Sturdynema multiembryonata (Upadhyay, 2017) in Xenentodon cancila (Osteichthyes: Belonidae) from the Gangetic Ecosystem

Abstract

The five years (2007–2012) consecutive parasitological investigations on freshwater crowfish, Xenentodon cancila conducted to learn the events in autogenic life cycle of Sturdynema multiembryonata. The S. multiembryonata is a roundworm with sturdy, spiny body in fresh water garfish peculiarly found taxonomically closer to gnathostomatoid roundworms. The developmental patterns and migratory behavior within the host was worked out critically. The findings were experimentally validated by oral feeding of eggs and developmental stages in dehelminthized experimental Swiss albino mice. The findings reflected exceptionally large body of advanced 3rd stage larva (AdvL3) displayed strong possibility of precocious development, which was at least four times in size than any of the gnathostomatoid worms reported so far. The presence of caudal papillae resembling roundish bosses described in Gnathostoma lamothei and G. miyazakii with peculiar single-spined ornamentation all over the body. The study concludes that the larvae of S. multiembryonata, reported here, may not enter into 4th stage of development, and advanced 3rd stage larvae (AdvL3) might transform into mature forms in a newer habitat, i.e. liver, within the body of newly reported definitive hosts, X. cancila. The establishment of larvae, without moulting, beyond the 3rd stage to attain maturity in the liver of experimental rodent hosts, corroborated the findings in natural fish definitive hosts. In the current investigation author wish to explore the precocious and autogenic development of S. multiembryonata, a roundworm with zoonotic potential which may provide a new dimension in the maintenance of healthy and disease free society based upon aquaculture.