Premium
Increased spawning activity of female Nile tilapia ( Oreochromis niloticus ) (L.) after stocking density and photoperiod manipulation
Author(s) -
De Lapeyre Boris Adrien,
MullerBelecke Andreas,
HorstgenSchwark Gabriele
Publication year - 2010
Publication title -
aquaculture research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.646
H-Index - 89
eISSN - 1365-2109
pISSN - 1355-557X
DOI - 10.1111/j.1365-2109.2010.02548.x
Subject(s) - stocking , oreochromis , nile tilapia , biology , photoperiodism , zoology , hatching , tilapia , fishery , fish <actinopterygii> , botany
This study was conducted to evaluate the effects of stocking density and photoperiod in increasing the reproductive performance of Oreochromis niloticus . In experiment 1, a change in stocking density (from 47.7 to 6.8 kg m −3 ) was performed, with groups of 48 females moved to single compartments. In experiment 2, 36 females experienced a 6L:18D photoperiod for 21 or 28 days (stocking density: 31.3 kg m −3 ) before being placed in individual compartments (stocking density of 6.9 kg m −3 , 12L:12D photoperiod). The spawning rates in experiment 1 (32.2%) and in experiment 2 (21 days: 65.2%, 28 days: 36.1%) were significantly higher than those in the control (17.7%). On the other hand, hatching and swim‐up fry rates were significantly lower in experiment 2 – 21 days (41.3%, 40.4%) but not in experiment 1 (64.0%, 56.3%) compared with the control (67.0%, 62.3%). The spawning rate in experiment 2 – 21‐day treatment group was the highest, while the number of eggs collected per female was significantly lower than that in the control. In experiments 1 (20.8%) and 2 (21 days: 44.4%, 28 days: 19.4%), the daily spawning rates were the highest 3 days after maintaining females in single compartments. The current experiment demonstrates how specific stocking density changes can be used to induce higher spawning rates in Nile tilapia.