STUDY OF SOME BODILY VARIABLES IN HYPOPHTHALMICHTHYS MOLITRIX SPECIES OF DIFFERENT AGES

Gabriela Dumitru, Elena Ciornea, C. Misăilă

Abstract
The present paper had the main aim to investigate some biometric corporal variables (total length and standard length of the body, the head’s length, the maxim height and the circumference) and gravimetric (the body's weight) for Hypophthalmichthys molitrix individuals in different stages of development (three summer-old and, respectively, four summer-old), from Research and Development Station for Aquaculture and Aquatic Ecology of Iasi. The analysis of parameters taken into study was realized with the biometric and gravimetric classical methods, calculating in the same time the values of main statistical indices which characterize a number of data (average, median, standard error and deviation, variance, range, the variation coefficient and of average's precision, as well as the limits of confidence intervals in which each variable oscillates). To establish the correlation and regression relations we chose to calculate the Pearson correlation indices and the outline of regression equations, and on the base of determination coefficient (R²) it was identified the number of cases in which the relation is available. On the basis of the obtained results we can mention, with a probability of 95%, the fact that at three summer-old Hypophthalmichthys molitrix representatives the total medium length of the body varies between 54.5-56.26 cm, and the weight between 1450.79-1607.21 g. In exchange, at four summer-old silver carp individuals present a total medium length between 64.59-66.54 cm and a medium weight between 2994.29-3109.71 g.

Key words: silver carp, age, Pearson correlation index