Maturity stage determination of female sergestid shrimp Lucensosergia lucens based on ovary color

Abstract

　The color variation and the maturation process of ovaries in mature female Lucensosergia lucens (Sergestidae) were studied by qualitative classification, digital image analysis, and histological observation. The classified color pattern in ovaries corresponded to the most developed oocyte stage. There were significant differences in L^∗, a^∗, and b^∗ values between the two groups of mature females with/without the oocytes of the later development stages. Multivariate analysis also described the color variations in those two groups. This study showed that ovary color variation was related to the development of the oocytes. The relationship between three qualitative ovary color patterns and the most developed oocyte stages was as follows: light blue-gray ovaries contained oocytes at primary-tertiary yolk granule stages (YGSs), greenish blue-gray ovaries contained oocytes at pre-maturation and maturation stages (PMS/MS), and dark blue-gray ovaries contained oocytes at YGSs or PMS/MS, both of which were almost the same in number.