per spawn are lower than with natural mates.
Originally, OI operated its breeding program by
producing maternal half-sib families. Production
of half-sib families depended on multiple spawns
of a single female within a 2-wk period. However,
this approach may confound genetic analysis by
introducing maternal and environmental effects.
In addition, the ratio of full-sib families to number
of dams was 1.2, whereas the goal of the breeding
program was to obtain a ratio of 2.0. A reduction
in the number of half-sib families in the breeding
program results in less accurate estimates of
genetic parameters. In light of the drawbacks
associated with producing maternal half-sib
families by AI, an experiment was conducted to
compare two AI techniques in order to determine
the most efficient method to produce offspring
for the breeding program at OI.