SOME BIOCHEMICAL ASPECTS OF REPRODUCTION IN FEMALE TRACHINOTUS OVATUS (CARANGIDAE)

SOME BIOCHEMICAL ASPECTS OF REPRODUCTION IN
FEMALE TRACHINOTUS OVATUS (CARANGIDAE)
ASSEM S. S. *, EL-SERAFY S. S.**, EL-GARABAWY M. M. *, ELABSAWY M. EL-G. * AND KALDUS S. K.**
*National Institute Of Oceanography and Fisheries.
** Faculty of science, Zagazig University, Banha branch.
Key words: Trachinotus ovatus, Ovaries, Total proteins and amino acids, total lipids and fatty
acids.
ABSTRACT
General pattern of gonadal development in female Trachinotus ovatus was
divided into six maturity stages, which are; immature, maturing, nearly ripe, ripe, spawning
and spent stages. The maximum value of gonadosomatic index (GSI) was attained in June
and July. Total protein content in ovaries varied according to different maturity stages
recording maximum value at immature ovaries and minimum at spawning and spent
ovaries. The values of GSI in ovaries were inversely correlated to their total protein content
at different maturity stages. Seven amino acids (proline, alanine, valine, methionine,
isoleucine, leucine and histidine) were found to increase significantly in ripe ovary,
followed by a significant decrease in both spawning and completely spent ovaries. While,
arginine and threonine reached their maximum concentration in the spawning period. On
the other hand, serine amino acid reached their minimum value in the ripe ovary. Total lipid
contents of ovaries reached their minimal values at immature stage, while the maximum
recorded value was at the nearly ripe gonad. The ovarian total lipid contents approximately
followed the same manner of the GSI according to the different maturity stages except in
spawning period. Many differences were detected in fatty acid concentrations in female
Trachinotus ovatus ovaries in relation to different maturity stages. Eicosapentaenoic acid
content varied according to the stage of sexual maturity. While, the maximum recorded
value of arachidonic acid was at the ripe stage. Palmitic acid and oleic acid had the highest
concentrations among fatty acids, while those with low concentrations were pentadecanoic
acid and gadoleic acid.