Effect of increase in temperature on the survival and growth of Macrobrachium amazonicum (Palaemonidae) in the Amazon

Macrobrachium amazonicum is a shrimp species distributed in freshwater habitats of Neotropical regions and is of great importance for the Amazonian economy. This study evaluated the effects of temperature increase on the survival and growth of M. amazonicum. For this, we distributed 360 M. amazonicum juveniles in 70 L tanks, and carried out a 90-day experiment with three treatments (T0:28 +/- 0.5 degrees C, or room temperature; T1: 30 +/- 0.2 degrees C; T2: 32 +/- 0.2 degrees C), using 4 replicate tanks each with 30 individual shrimp. Culture-tanks were connected to a recirculation system with biofiltration and constant aeration. Animals were fed twice a day using shrimp pelleted commercial food. After 90 days of trial, the total length and body mass gain of the animals cultured at room temperature was 78% and 433%, respectively. The specific growth rate, condition factor, weight gain, and length and survival of animals cultured at 30 and 32 degrees C were lower than those cultivated at 28 degrees C, and feed conversion was higher. Therefore, water temperature of 30 and 32 degrees C may compromise growth and survival of M. amazonicum during cultivation, none of the extreme temperatures may be recommended in practice.