On the biology and morphology of Echinococcus granulosus (Batsch, 1786) of buffalo–dog origin

Abstract

The present material of buffalo–dog origin could not be transmitted to the laboratory animals, such as white rats, white mice, rabbits, golden hamsters, guinea-pigs and chicks.Secondary development took place only in mice.The strobilar phase was infective to a cat but did not show sexual differentiation even at 30 days, and worms were further observed to be at a degenerative stage.The buffalo was highly suited to the perpetuation of the parasite, forming larger cysts and massive production of scoleces; nearly 90% of the cysts were fertile.The strobila had mostly two segments and not more than three.The number and distribution of testes were more posterior to the genital pore and were also observed posterior to the vitellaria, occasionally.The position of the genital pore in the gravid as well as mature segments was both anterior and posterior but with an average of 52.8%.Uterine sacculations were observed to range from 28 to 54.Echinococcus material of buffalo–dog origin does not appear to fall into a definite ‘subspecies’ pattern. It is suggested that it be merely recognized as a further ‘mutant’, the existence of which can be accounted for on theoretical grounds.The authors are thankful to the Director, Indian Veterinary Research Institute, and to Dr H. D. Srivastava, Head of Division of Parasitology, I.V.R.I., for providing the necessary laboratory facilities.