Haematological Study of a Species of Rockfish, Sebastiscus marmoratus-V

Seasonal changes of Blood Elements, Electrophoretic Pattern of Serum Proteins and their Percentage Fractions

Abstract

From the results of preliminary experiments made during the preceding five years, using 177 specimens of rockfish, Sebastiscus marmoratus, it became evident that a few individual fish are enough for the analysis of the seasonal change of the blood elements of this species (Table 1, Fig. 1). Three rockfish were, therefore, kept in a concrete tank (0.7m³) of circulating sea water during the period of one year. The blood was drawn six times from each individual to compare the seasonal change of the blood elements (Table 2).
Sampling of the blood, measurements of the specific gravity, serum protein and haematocrit, and electrophoresis were done following the same techniques used in the previous studies.
In both male and female, the specific gravity of the blood, the amount of serum protein and haematocrit value were most high during October and November, the period when spermatozoa are discharged in the male. The lowest values were found in February, when the female of this species is usually liberating viviparous larvae (Fig. 2).
Five fractions were observed in the electrophoretic pattern of serum protein. These components were separated clearly throughout the year in the female, while sometimes they were not separated distinctly in the male (Fig. 3).
The percentage of serum protein fractions varied with the season. Component I showed the minimum and Component In the maximum during the period discharging spermatozoa, in both the male and the female (Fig. 4). It is of interest to note that the change in the amount of blood elements as well as its seasonal percentage occurrence seemed to coincide fairly well with some physiological characteristics, i.e. the development of sexual glands, of the rockfish.