Etude de quelques paramètres de la reproduction (RGS/ RHS) chez quelques espèces de poissons cas de l’espèce Sardinella aurita (Valenciennes,1847)

Abstract

The allache Sardinella aurita (Valenciennes.1847) is a pelagic species of economic importance, omnipresent on the Algerian coast and abundant on almost all the fishing areas of the coast of Mostaganem, nevertheless there is almost a rarity at the level of stalls with a prohibitive price especially during the winter season. The objective of this research study is to implement the biometric and reproductive parameters of the fish species Sardinella aurita. The research study had focused on 81 individuals of this species for the three months, February, March, and April 2023. Before, we had weighed the whole fish, the liver, and the gonads after dissection, then taken measurements of the total lengths and at the fork, the evaluation of the ratios, gonado-somatic (RGS) and hepatosomatic (RHS). This evaluation is followed by the highlighting of the relationship on the one hand between the two different sizes, and on the other hand between the height and the weight of each individual. The evaluation of the sex ratio showed that the percentage of femininity is higher during the month of February. On the other hand, the percentage of masculinity, its evolution is opposite to that of femininity, it is high during the month of April. The evolution of RHS in males tends towards a peak in March, with a minimum in February, and a slight decrease in April. Nevertheless, the RHS in females takes a downward path identical to that of the RGS with a maximum in February. The relation total length (Lt)-fork length (Lf) according to sex, presents the lowering allometry, and consequently the total length (Lt) increases relatively less quickly than the length at the fork (Lf) and this for the two sexes. The relation total length and weight presents the increasing allometry, the mass increases proportionally more quickly than the length for the two sexes. At the end of these results, we found a slight female predominance, and that the weight increases faster than the height. Keywords: