Regresar

Weekly collection of tilapia seeds (Oreochromis spp.) as a productive strategy in concrete tanks

Abstract:

A study was conducted with the objective of evaluating egg production and fecundity in breeding stock of tilapia of the Oreochromis genus reared in concrete tanks in a fish farm located in Andrés Bello County of Trujillo State, Venezuela. The volume and weight of the harvested eggs, number of eggs/mL, weight and volume/egg, fecundity and relative fecundity of the spawned females were considered as dependent variables. At seven-day intervals during seven consecutive weeks, all females in the tanks were captured, and eggs removed from the buccal cavity. According to the developing stage, the eggs were classified in egg without hatching (F1) and eggs in hatching process (F2). Data were examined by analysis of variance using the GLM procedure of SAS. The volume of eggs spawned and number of eggs/mL were greater (P < 0.05), and the weight of each egg was lower (P < 0.05), in the F1 than in F2 stage (P < 0.05); however, spawned egg weight and volume/egg were statistically similar between groups (P < 0.10). Fecundity (1064.4 ± 83.7 versus 665.6 ± 109.1, respectively; P < 0.01) and relative fecundity (125.5 ± 10.3 versus 75.0 ± 13.5, respectively; P < 0.01) were grater in F1 than in F2. In conclusion, weekly manual spawning of tilapia females allowed the constant production of eggs for hatching and subsequent larval production. Also, a greater egg production was determined in the F1 than in F2 developmental stage.