Hatchery production of Oreochromis niloticus L. at different sex ratios and stocking densities
Abstract
The influence of various sex ratios and stocking densities on hatchery production of Nile tilapia, Oreochromis niloticus L., was studied in land-based (concrete tanks) and lake-based (hapa nets) systems. In both hatchery systems, egg and fry production was maximum at a sex ratio of 4:1 females to males and a density of 4 females per m2.
Seed production varied significantly among treatments at different periods of the year. In concrete tanks, significantly high seed production of 12.98 and 11.77 eggs and fry per spawner per day was obtained in March and August, respectively. In hapa nets, irrespective of sex ratios, 10.18 seeds per spawner were collected daily in March.
In relation to the broodstock density in concrete tanks, significantly bigger daily harvests of 13.41 and 13.00 eggs and fry per spawner were produced in late February and March, respectively. In hapa nets, daily harvests of 8.95 and 7.74 eggs and fry per spawner were the highest seed production levels which occurred in April and March, respectively.
Seed production was significantly higher in concrete tanks than in hapa nets while insignificant differences (P>0.05) were found among sex ratio and broodstock density treatments.
Description
Contribution No. 228 of the Aquaculture Department, SEAFDEC.
Citation
Bautista, A. M., Carlos, M. H., & San Antonio, A. I. (1988). Hatchery production of Oreochromis niloticus L. at different sex ratios and stocking densities.Publisher
ElsevierSubject
Collections
- Journal Articles [1051]
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