Carotenoid composition in wild-caught spotted scat (Scatophagus argus) broodstocks: effects on gonad development

The carotenoid reserves of broodstocks have a considerable impact on reproductive performance, maturity, fecundity, spawning, and yolk-sac larvae quality. The purpose of this study was to elucidate the most effective strategy for enriching broodstock in artificial breeding programs by examining changes in the carotenoid profile of wild-caught spotted scat (Scatophagus argus) broodstocks during the reproductive season. The predominant carotenoids such as fucoxanthin, astaxanthin, lutein, and β-carotenoids were examined in muscle, liver, and gonad (testis and ovary) samples from both the genders. The results revealed that total carotenoid levels differed significantly (p < 0.05) among tissues during sexual maturation. The muscle fucoxanthin levels increased gradually (0.014 ± 0 .01 < 0.017 ± 0.00 < 0.019 ± 0.01 mg/100 g) during testicular maturation and were comparatively higher than that of the liver and testis. The astaxanthin content of the ovary was relatively low and increased with ovarian maturation (2.013 ± 0.18 < 6.106 ± 0.28 < 8.871 ± 0.73 mg/100 g). The scat's mature ovary (9.446 ± 0.53 mg/100 g) had a higher concentration of lutein in comparison with testis (0.821 ± 0.07 mg/100 g). In the testis, the highest concentration of β-carotene could be observed during the mature stage (1.765 ± 0.08 mg/100 g). In female scat, the β-carotene content of muscle showed an inverse relationship with maturation indicated by a gradual decrease from immature stage. Finally, it is proposed that carotenoids are preferentially mobilized and conserved in the gonads, which are indispensable to improve gonadal development and the productive potential of S. argus, a leading candidate species.