Reviews in Fish Biology and Fisheries 10: 1–25, 2000.
© 2000 Kluwer Academic Publishers. Printed in the Netherlands.
Reproductive physiology of female tilapia broodstock
& N.R. Bromage
Institute of Aquaculture, University of Stirling, Stirling, Scotland FK9 4LA;
Present address: Peripheral Neuro-
pathy Unit, Department of Neurology, Imperial College School of Medicine, Area A, Ground Floor, Hammersmith
Hospital, Du Cane Road, London, W12 ONN, UK (E-mail: firstname.lastname@example.org);
Accepted 17 September 1999
Abstract page 1
General introduction 2
Taxonomy and modes of reproduction in tilapia 3
Ovarian development 3
Spawning periodicity 10
Fecundity and egg size 14
Key words: broodstock, fecundity, ovarian development, spawning periodicity, tilapia
Tilapiine ﬁsh have become one of the most commercially important groups of cultured freshwater ﬁsh with
in excess of 850 000 tonnes produced annually in a range of countries (e.g. Thailand, Taiwan, China, Philippines,
Belgium and the USA). However, poor broodstock productivity, owing to low fecundity and asynchronous
spawning cycles, remains one of the most signiﬁcant outstanding constraints upon commercial tilapia production
and its future expansion. This paper reviews current understanding of the reproductive physiology of tilapia
with particular emphasis upon those factors deemed critical to successful broodstock management. Special
emphasis is placed upon factors such as fecundity, egg size, spawning periodicity, ovarian development and the
exogenous and endogenous regulatory mechanisms involved in their control. Mouthbrooding species exhibit
higher levels of parental care but fecundity is lower and egg size larger than in substrate-spawning species.
Fecundity, the number of eggs oviposited per spawning act, can be < 350 in mouthbrooders such as Oreochromis
mossambicus (Peters) but can exceed 12 000 in substrate-spawners such as Tilapia zillii (Gervais). Eggs produced
by mouthbrooders normally exceed 2 mm in diameter whilst those of substrate spawners average only 1.5 mm.
Interspawning intervals of mouthbrooders generally average 30–50 days whether the ﬁsh are held in natural or
artiﬁcial conditions, although substrate-spawning species such as Tilapia zillii can re-spawn after only 6 or 7
days. The dynamics of the asynchronous pattern of ovarian development adopted by tilapiines are complex and
result in the ovary being dominated by late-vitellogenic/maturing oocytes as early as 8–10 days after spawning.
Advancement of our understanding of these key areas will be essential if the present constraints on tilapia culture
are to be overcome.