Although spermatocrit, viability, and motility are scored
relatively easily, the usefulness of motility measurements
has long been questioned because subjective scoring
methods are used and have produced variable results [20].
Therefore, measures of sperm quality should be validated
against successful egg fertilization. In this work, we found
that higher osmolality, motility, duration of motility, and
sperm concentration were associated with the highest rate
of fertilization in the treatment with the highest concentration
of astaxanthin (A150). Similar correlations between
sperm motility and fertilization capacity have already been
reported in carp [54], turbot [55], and rainbow trout [56]. If
sperm quality can be related to fertilizing ability, then, it is
possible to use computer-assisted sperm analysis to
routinely assess a very wide range of freezing protocols
without the requirement of females and without the variability
inherent in the use of eggs from different female
goldfish.