Hyperplastic development and hypertrophic growth of muscle fasciculi in Macrobrachium rosenbergii (De Man 1879)

Abstract

Muscle growth dynamics was analyzed in the giant freshwater prawn, Macrobrachium rosenbergii, using 30 full-sib families, 10 each of three stocks collected from different parts of India. The objectives of this study were to understand the muscle growth pattern in M. rosenbergii and to identify stocks with high performance. The diameters of individual fasciculi were measured and total fasciculi numbers per mm2 at different hapa-ages (i.e., 60, 90, 120, 150 and 180 days) were calculated. The average muscle fasciculi diameter ranged from 13.50 ± 2.5 to 23.96 ± 2.2 μm at different hapa-ages. Significant variations were observed between the stocks at all hapa-ages except 150 and 180 days and between tanks at certain hapa-ages. The average muscle fasciculi numbers per mm2 varied with hapa-age from 11.16 ± 2.6 to 23.96 ± 4.3; significant variations were observed in the fasciculi numbers per mm2 between stocks and sires at certain hapa-ages. By using non-parametric smoothing technique, it was found that the muscle growth in M. rosenbergii is mainly due to hypertrophy but the recruitment of the muscle faciculi do takes place at around 120 days of hapa-age. The findings of this study appear to have enormous potential in genetic improvement programmes.