Evaluación del ph y oxígeno disuelto y su influencia en la supervivencia de alevines de (oreochromis niloticus) cultivados en la granja experimental Santa Inés de la Facultad de Ciencias Agropecuarias.

Abstract

In fish farming, normal growth behavior depends on factors such as pH and dissolved oxygen in the water, however the homogenization of fish size and the correct dosage of exogenous feed is a critical factor for an efficient production system in cages. Using floating cages, it was determined that fish that received supplemental feed (UCA2 and UCA3) grouped with similar sizes achieved the best growth and survival rates (up to 95%), while fish without exogenous feed (VSA5 and USA4) showed lower productive performance, high mortality, and poor somatic development. This confirms that supplemental nutrition is a determining factor for zootechnical performance in cage farming systems. It was observed that morphometric variability in fish influenced intraspecific competition, negatively affecting access to food and generating hierarchical dominance, which was reflected in mortality. The VCA1 treatment, with fish of high size variability and the addition of exogenous feed, showed intermediate growth, suggesting that feed can partially mitigate the effects of intraspecific competition. However, the absence of nutritional supplementation in cages with heterogeneous fish (VSA5) accentuated growth inequality and reduced survival to 43.75%. In conclusion, the selection of homogeneous cohorts and the inclusion of exogenous feed are key factors in optimizing tilapia production in floating cages.