Morphological observations of Toxocara canis egg development in vitro

doi:10.12140/j.issn.1000-7423.2019.04.020

Abstract

Abstract:

To observe the morphological changes of Toxocara canis egg development, an automatic microscopic photographing system was setup to track and record the whole process of T. canis egg development during continuous 21-day egg culture in vitro in this study. The results demonstrated that the whole development of T. canis egg in vitro was divided into 12 developmental stages including one-cell, two-cell, three-cell, four-cell, early-morula, late-morula, blastula, gastrula, pre-larva, L1 (the first stage larva), pre-L2 and L2 stages. The cell started to divide to form two-cell egg in 24 hours culture, appeared as 3-4 cells egg, morula, blastula and gastrula stages in 3-6 days. Total 22.5% of eggs developed to embryonated L1 with phototactic movements in 7 days. Total 10.67% eggs developed to infective embryonated L2 in 8 days. At 17-day post culture, the infective larva have been hatched and the whole eggshell collapsed. These data provide more information for the developmental biology of T. canis egg in vitro.

Key words: Toxocara canis, Eggs, Development, Morphological changes

CLC Number:

R383.11

Yi-lin ZHANG, Sen-zhao ZHANG, Xiao-bin GU, Guang-you YANG, Yue XIE. Morphological observations of Toxocara canis egg development in vitro[J]. CHINESE JOURNAL OF PARASITOLOGY AND PARASITIC DISEASES, 2019, 37(4): 486-489.

Figures/Tables 3

References 23

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