Growth pattern of all-female perch (Perca fluviatilis L.) juveniles - is monosex perch culture beneficial?

P>The study objective was to evaluate the enhanced profitability of monosex all-female stock (MS) culture compared to bisexual stock (BS) of Eurasian perch (Perca fluviatilis L.) under intensive conditions. Monosex all-female stock was produced by mating masculinized females (neomales) with common females of a local strain; the bisexual stock was obtained from a local strain perch broodstock. Preceded by pond-nursing (60 days) and habituating (14 days) periods, the experiment lasted 126 days. Perch were held in six 50-L aquaria connected to a recirculation system, with each group tested in triplicate. No significant differences (P = 0.07) in total survival were observed between all-female and bisexual stock after 126 days of rearing, but MS gained 20% more (P = 0.04) in total body weight (final weight 25.2 +/- 9.7 g; mean +/- SD) than BS fish (21.0 +/- 7.5 g). It is suggested that the culture of monosex female perch might therefore be of significant economic benefit. Overall feed conversion ratio for tanks with BS (1.43 +/- 0.21) was significantly (P = 0.02) higher than in tanks with MS (1.30 +/- 0.11) perch.