Differences in the spermatozoa and ova of two species of giant African land snails (Archachatina marginata and Achatina achatina)

Abstract

A comparative study of the gametes of two species of Giant African Land Snails; Archachatinu marginata and Achatina achatina was carried out. Three groups of snails weighing 80-100,101-150 and 151-250 g were used in a 3x2 factorial design, with 5 replicates, involving a total of 30 snails. Albumen gland, little hermaphrodite duct, spermotheca and ovo-testis were examined for the presence of ova and spermatozoa. The morphology of the spermatozoa and ova of both species Was studied. Ova were found in the albumen gland and ovo-testis. Spermatozou were only found in the little hermaphrodite duct. Spermatozoa head and tail lengths were not significantly (P>0.05) different between species, while the mid-piece length was significantly (P<0.05) different. Liveweight group 101-150 g had the highest number of spermatozoa and ova count in both species. Morphologically, spermatozoa head, collar and mid-piece crest differed between species Archachatina marginata spermatozoa had pointed head, longer collar and highest number of mid-piece crests compared to Achatina achatina. Ova seen in the ovo-testis of A. marginata were larger compared to those seen in A. achatina. It was concluded from the study that there are differences in the morphology and dimensions of their germ cells.