Morphological features of development of Strongyloides westeri (Nematoda, Rhabditida) in vitro

Keywords: Strongyloides; horses; nematode eggs; larvae; biological properties; morphometry

Abstract

Strongyloides westeri (Ihle, 1917), a parasitic horse nematode, has an unusual lifecycle, which allows it to exist for a long time in the environment. Morphometric features of eggs, larvae and free-living S. westeri were studied in vitro under different temperature regimes. The optimal temperature for their embryonic development is 25 °С, under which 90% of the first stage rhabditiform larvae are formed and released within 7 hours of cultivation. The temperatures of 20 and 30 °С are less favorable for their development. Embryonic development of Strongyloides has four stages that differ in morphology and size. The eggs of a parthenogenetic female are 3.7% longer and 19.6% wider than eggs isolated from free-living females of S. westeri. In embryogenesis, the eggs shorten by 4.4 μm (6.5%) and widen by 5.35 μm (8.3%). New data were obtained on postembryonic development of S. westeri. The differential morphometric features of stage 1 and 2 rhabditiform larvae which grow both in length and width (33.7% and 30.4% respectively) are established. The development of filariform larvae is associated with loss of bulbous thickening and formation of cylindrical oesophagus. Simultaneously, the body elongates, and the gut becomes shorter. Differential morphometric features of free-living males and females of S. westeri are the length and width of body, length of oesophagus, gut, tail end, and size of spicules. Postembryonic development of the free-living and parasitic generations from rhabditiform larvae is temperature-dependent. Most of the free-living generations of Strongyloides (54.0%) are formed at 20 °С, and filariform larvae mostly (70.0%) develop at 30 °С. The obtained results of morphological studies improve differential diagnostics of the nematode at various stages of development and further advance the study of its intraspecific variability.

References

Anderson, R. C. (2000). Nematode parasites of vertebrates: Their development and transmission. CABI Publishing, Wallingford, Oxon (UK).


Araujo, J. M., Araújo, J. V., Braga, F. R., Tavela, A. O., Ferreira, S. R., Soares, F. E., & Carvalho, G. R. (2012). Control of Strongyloides westeri by nematophagous fungi after passage through the gastrointestinal tract of donkeys. Revista Brasileira de Parasitologia Veterinária, 21, 157–160.


Boyko, A. A., & Brygadyrenko, V. V. (2016). Vlijanie vodnogo nastoja lekarstvennyh rastenij na lichinok Strongyloides papillosus (Nematoda, Strongyloididae) [Influence of water infusion of medicinal plants on larvae of Strongyloides papillosus (Nematoda, Strongyloididae)]. Visnyk of Dnipropetrovsk University. Biology, Ecology, 24(2), 519–525 (in Russian).


Boyko, A. A., & Brygadyrenko, V. V. (2017). Changes in the viability of Strongyloides ransomi larvae (Nematoda, Rhabditida) under the influence of synthetic flavourings. Regulatory Mechanisms in Biosystems, 8(1), 36–40.


Blaxter, M. L., De Ley, P., Garey, J. R., Liu, L. X., Scheldeman, P., Vierstraete, A., Vanfleteren, J. R., Mackey, L. Y., Dorris, M., Frisse, L. M., Vida, J. T., & Thomas, W. K. (1998). A molecular evolutionary framework for the phylum Nematoda. Nature, 392(6671), 71–75.


Carlson, C. J., Burgio, K. R., Dougherty, E. R., Phillips, A. J., Bueno, V. M., Clements, C. F., Castaldo, G., Dallas, T. A., Cizauskas, C. A., Cumming, G. S., Doña, J., Harris, N. C., Jovani, R., Mironov, S., Muellerklein, O. C., Proctor, H. C., & Getz, W. M. (2017). Parasite biodiversity faces extinction and redistribution in a changing climate. Science Advances, 3(9), e1602422.


De Blieck, L., & Baudet, E. A. R. F. (1920). Verdere onderzoekingen over de biologie en den infecticweg von de larven von Strongyloides westeri. Tijdschr Diergeneesk, 47, 497.


Dewes, H. F., & Townsend, K. G. (1990). Further observations on Strongyloides westeri dermatitis: Recovery of larvae from soil and bedding, and survival in treated sites. New Zealand Veterinary Journal, 38, 34–37.


Dorris, M., Viney, M. E., & Blaxter, M. L. (2002). Molecular phylogenetic analysis of the genus Strongyloides and related nematodes. Journal of Parasitology, 32(12), 1507–1517.


Eberhardt, A. G., Mayer, W. E., & Streit, A. (2007). The free-living generation of the nematode Strongyloides papillosus undergoes sexual reproduction. Journal of Parasitology, 37(8–9), 989–1000.


Goater, T. M., Goater, C. P., & Esch, G. W. (2014). Parasitism: The diversity and ecology of animal parasites. Cambridge University Press, Cambridge.


Grant, W. N., Stasiuk, S., Newton-Howes, J., Ralston, M., Bisset, S. A., Heath, D. D., & Shoemaker, C. B. (2006). Parastrongyloides trichosuri, a nematode parasite of mammals that is uniquely suited to genetic analysis. International Journal for Parasitology, 36, 453–466.


Ivashkin, V. M., & Dvojnos, G. M. (1984). Opredelitel' gel'mintov loshadej [Determinant of horse helminths]. Naukova Dumka, Kyiv (in Russian).


Jones, J., Gheysen, G., & Fenoll, C. (2011). Genomics and molecular genetics of plant – nematode interactions. CBS Publishers, New Delhi, India.


Kennedy, M. M., & Harnett, W. (2013). Parasitic nematodes: Molecular biology, biochemistry and immunology. United Kingdom.


Lee, D. L. (2002). The biology of nematodes. Taylor and Francis, London.


Levine, N. D. (1980). Nematode parasites of domestic animals and of man. Burgess Publishing Company, Minneapolis.


Lucena, R. B., Fighera, R. A., & Barros, C. S. L. (2012). Mortalidade em potros associada ao parasitismo por Strongyloides westeri. Pesquisa Veterinária Brasileira, 32(5), 401–404.


Lyons, E. T., Drudge, J. H., & Tolliver, S. C. (1973). On the life cycle of Strongyloides westeri in the equine. Journal of Parasitology, 59, 780–787.


Lyons, E. T., Tolliver, S. C., Rathgeber, R. A., & Collins, S. S. (2007). Parasite field study in Central Kentucky on thoroughbred foals (born in 2004) treated with pyrantel tartrate daily and other parasiticides periodically. Parasitology Research, 100(3), 473–478.


Lyons, E. T., & Tolliver, S. C. (2015). Review of some features of the biology of Strongyloides westeri with emphasis on the life cycle. Helminthologia, 52(1), 3–5.


Lyons, E. Т., & Tolliver, S. C. (2014). Strongyloides westeri and Parascaris equorum: Observations in field studies in Thoroughbred foals on some farms in Central Kentucky, USA. Helminthologia, 51(1), 7–12.


Malygin, S. A. (1957). Anatomija i morfologija vidov roda Strongyloides (Grassi, 1879) domashnih zhivotnyh [Anatomy and morphology of species of the genus Strongyloides (Grassi, 1879) of domestic animals]. Sbornik Rabot po Gel'mintologii, 388–395 (in Russian).


Miller, F. L., Bellaw, J. L., Lyons, E. T., & Nielsen, M. K. (2017). Strongyloides westeri worm and egg counts in naturally infected young horses. Veterinary Parasitology, 248, 1–3.


Minato, K., Kimura, E., Shintoku, Y., & Uga, S. (2007). Effect of temperature on the development of free-living stages of Strongyloides ratti. Parasitology Research, 102(2), 315–319.


Sakamoto, M., & Uga, S. (2013) Development of free-living stages of Strongyloides ratti under different temperature conditions. Parasitology Research, 112(12), 4009–4013.


Sandground, J. H. (1925). Speciation and specificity in the nematode genus Strongyloides. The Journal of Parasitology, 12(2), 59–80.


Santos, K. R., Carlos, B. C., Paduan, K. S., Kadri, S. M., Barrella, T. H., Amarante, M. R., Ribolla, P. E., & da Silva, R. J. (2010). Morphological and molecular characterization of Strongyloides ophidiae (Nematoda, Strongyloididae). Journal of Helminthology, 84(2), 136–142.


Schuurmans, J. H., & Stekhoven, J. (1930). Untersuchungen über Nematoden und ihre Larven V. Strongyloides westeri Ihle und Ihre Larven. Zeitschrift für Parasitenkunde, 2(3), 297–309.


Shiwaku, K., Chigusa, Y., Kadosaka, T., & Kaneko, K. (1988). Factors influencing development of free-living generations of Strongyloides stercoralis. Parasitology, 97(1), 129–138.


Thamsborg, S. M., Ketzis, J., Horii, Y., & Matthews, J. B. (2016). Strongyloides spp. infections of veterinary importance. Parasitology, 144(3), 274–284.


Thompson, F. J., Barker, G. L., Hughes, L., Wilkes, C. P., Coghill, J., & Viney, M. E. (2006). A microarray analysis of gene expression in the free-living stages of the parasitic nematode Strongyloides ratti. BMC Genomics, 7, 157.


Tsuji, N., & Fujisaki, K. (1994). Development in vitro of free-living infective larvae to the parasitic stage of Strongyloides venezuelensis by temperature shift. Parasitology, 109(5), 643–648.


Viney, M. E. (2006). The biology and genomics of Strongyloides. Medical Microbiology and Immunology, 195, 49–54.


Vislobokov, V. A. (2008) Migracija lichinok Strongyloides westeri vo vneshnej srede [Strongyloides westeri larvae migration in the external environment]. Materialy Nauchnoj Konferencii VOG RAN “Teorija i praktika bor'by s parazitarnymi boleznjami”, 9, 108–109 (in Russian).


 

Published
2018-02-18
How to Cite
Gugosyan, Y. A., Yevstafyeva, V. A., GorbО. А., Melnychuk, V. V., YasnolobI. О., Shendryk, C. M., & PishchalenkoM. А. (2018). Morphological features of development of Strongyloides westeri (Nematoda, Rhabditida) in vitro. Regulatory Mechanisms in Biosystems, 9(1), 75-79. https://doi.org/10.15421/021810