Length-weight Relationship of Heterobranchus bidorsalis (Geoffroy st. Hilaire 1809) Diploid and Triploid Progenies raised under the same Environmental condition

Résumé

Twenty specimens of triploid with weight and length ranging from 207-300g and 29-32cm; diploid 150-200g and 23-28cm Heterobranchus bidorsalis (Geoffroy St. Hilaire 1809) were subjected to morphometric and meristic characterization, length-weight relationship and condition factor evaluation. Triploid specimens had the higher values in all the parameters examined and were significantly different (P<0.005). Regression analysis of diploid and triploid show the ranges of values (K) of 0.802 1.453 and 0.838 0.906 respectively, for condition factor (k) while the relative condition factor values (Kn) ranged between 0.869 1.087 and 0.968 1.038 respectively. Weight increases directly as the total length increases for both diploid and triploid indicating isometric growth. The R2 in triploid was higher (96.8%) than in diploids (42.4%). In diploid progenies, the length by weight was significantly different (P<0.05) in triploid. Triploid progenies need no special adaptive environment or technique for rearing. Therefore, diploid and triploid progenies can be successfully cultured simultaneously under the same environmental condition.