The effect of stocking density on the growth of apple snails native Pomacea bridgesii and exotic Pomacea lineata (Mollusca, Gastropoda)

The demand for alternative food sources is currently in evidence in the world and, therefore, the culture of animal species considered not conventional makes this theme relevant and appropriate. In the present study, the species Pomacea lineata and Pomacea bridgesii, each with three stowage densities (0.5 [T1], 1 [T2], and 1.5 [T3] animal/L), were tested. They were analyzed regarding growth rate, weight gain, final biomass, feed conversion and percentage of survival. There was not any statistically significant difference between the different densities for both species. The final average weight in the three waterworks did not differ significantly in P. bridgesii. In P. lineata, T1 (22.3 +/- 1.80g) was significantly higher than T2 and T3. On the other hand, the absolute gain of weight in P. lineata and P. bridgesii was significantly higher in T1 (21.9 +/- 1.80g and 37.2 +/- 6.34g) than in T2 and T3 respectively. In contrast, the gain of biomass of P. lineata and P. bridgesii was significantly higher in T3 (276.3 +/- 33.16g and 431.4 +/- 37.20g) than in T1 and T2, respectively. Based on the results obtained, all species studied presented potential for aquaculture, mainly P. bridgesii, distinguished for showing a better development even in waterworks with higher densities.