Correlation of growth-related traits and their effects on body weight of the mud crab (Scylla paramamosain)

Abstract

ABSTRACT. In this study, we analyzed the correlation of 20 growthrelated traits and their effects on body weight of Scylla paramamosain. The correlation coefficients in all trait pairs were significantly high, ranging from 0.551 to 0.999. Among 19 X-Y pairs, the correlation coefficient between traits X 1 and Y was the highest, whereas that between X 13 and Y was the lowest. Path analysis indicated that only two traits (X 1 and X 14 ) can significantly affect body weight (Y) directly, with the path coefficients being 0.800 and 0.198, respectively. The determination coefficients (d i ) of traits X 1 and X 14 to body weight were 0.640 and 0.039, respectively, and the total d i was 0.965, indicating that both traits were the key factors affecting body weight. Moreover, traits X 1 and X 14 were confirmed to be significantly related to body weight. Finally, a best-fit linear regression equation was constructed as Y = 4.192X 1 + 2.242X 14 -169.737.

Characteristics of growth traits and their effects on body weight of G1 individuals in the mud crab (Scylla paramamosain)

“…Trait BW had the largest variation (25.21 and 50.96% in females and males, respectively), as observed in our previous study in wild individuals of S. paramamosain (CV = 56.09%; Ma et al, 2013). Traits DLS1 and CFW exhibited the lowest variation in females (CV = 7.83%) and males (CV = 14.07%), while trait DLS1 had the lowest variation in the wild population.…”

“…The multiple correlation coefficients between morphological traits and body weight was high (more than 0.85) in both females and males, and approximately equal to the determination coefficients; hence, the two traits (CL and DLS2) and the three traits (BH, FFHC and MLP2) could be considered as the key factors affecting BW in female and male individuals of S. paramamosain. In the previous study, two traits (CL and FFHC) were found to have significant direct effects on BW (P < 0.05) in both females and males (Ma et al, 2013). By using path analysis, the main factors affecting body weight have been found in other aquaculture animals, such as Eriocheir sinensis (Geng et al, 2007), Pinctada martensii (Deng et al, 2008), and Portunus trituberculatus (Liu et al, 2009).…”

“…In addition, limited differences of morphological traits of individuals from different coasts of southeastern China were determined by morphological discriminant analysis (Li et al, 2004). A very significant correlation (P < 0.01) was found in each pair of 20 growth traits, of which two traits, carapace length and fixed finger height of the claw, were suggested to play an important role in affecting body weight (P < 0.01) (Ma et al, 2013). Beside the above, there is little information about the characteristics of morphological traits available in S. paramamosain.…”

Optimization of selective breeding through analysis of morphological traits in Chinese sea bass (Lateolabrax maculatus)

“…The determination (d i ) and co-determinant (d ij ) coefficients were calculated using the following formulae (described by Ma et al, 2013): …”

First genetic linkage map for the mud crab (Scylla paramamosain) constructed using microsatellite and AFLP markers

“…The genetic population diversity of wild S. paramamosain is high, and significant correlations have been found between genetic distance and geographic distance among different populations (Ma et al, 2012). Moreover, significant associations between each pair of 20 growth-related morphologic traits have been tested (Ma et al, 2013a). Under artificial conditions, hatchery stocks show significantly faster growth rates than wild populations (Utet al, 2007), and genetic differences among artificial families are much higher than among wild populations (Cui et al, 2011a).…”