Gametes from New Zealand Haliotidae and consideration of some factors affecting their viability

Abstract

Section 1 Gametes from Haliotis iris, H. australis, H. virginea virginea and H. virginea morioria were described. Electron miscroscope observations of sperm morphology allowed all species, except H. virginea subspecies, to be separated on the basis of differences in the size and shape of their acrosome granule. Results are discussed with reference to other described species of Haliotis. Discussions are presented on the use of sperm for species identification, determining systematic position and in tracing animal phylogenies. Section 2 Three experiments were conducted at 16.5°C to assess H. virginea virginea gamete viability related to time. Aged eggs inseminated with fresh sperm displayed 82.5% to 98% viability over a 6 hr 20 min. period. 4 hr 11 min. old sperm fertilised 96% of fresh eggs but viability rapidly decreased to 0.5% by 6 hr 30 min. Aged eggs and sperm displayed high viability for only 2 hr. Results indicated that sperm lost viability well in advance of eggs. The viability of aged eggs and sperm from H. virginea virginea was tested at 6.9°C, 11.0°C, 13.0°C, 15.9°C and 18.0°C. High viability was retained for the longest time at 15.9°C.