On the Life Cycle of Spirocerca lupi: Preinfective Stages in the Intermediate Host

Abstract

The development of the preinfective stages of S. lupi has been described and illustrated and the details of morphology given for the first time.The sex of the first stage juveniles can be distinguished by locating the position of the genital primordium. On an average, the first stage juveniles measure 0·39 mm. in length and 0·036 mm. in breadth, early second stage 0·78 and 0·044 mm. and the advanced second stage 1·40 mm. and 0·63 mm. respectively. The second stage juveniles obtained from beetles were not infective to dogs.