Stress in Salminus brasiliensis fingerlings due to different densities and times of transportation

Abstract

The stress in dorado fingerlings (Salminus brasiliensis) caused by transportation at densities of 5, 10, and 15g/l after 4, 8, and 12h was evaluated by the concentration of tissue cortisol measured by ELISA. The conditions of transportation were simulated on an orbital table shaker with horizontal movements, inside 15 litres plastic bags filled with 4 litres of water and pure oxygen. Cortisol concentrations increased in all densities after 4h of transportation converging to a common concentration at the end of the tested times. Electrical conductivity of water increased with density and transportation time. The transportation caused stress on fish, but the increase on density and in times of transportation did not cause mortality to fingerlings. The transportation of S. brasiliensis fingerlings can be done without mortality or apparent injuries to animals until the maximum analyzed density of 15g/l and up to 12h.

<b>Long-term transportation of juvenile pacamãs <i>Lophiosilurus alexandri</i> at different densities

“…A similar result was reported in a previous study of the same species using juveniles with an average weight of 2.52 g stocked at a density of 54 animals in 5 L of water for 7.5 hours . Moreover, similar results were found by Adamante et al (2008) who recommended 12-hour transportation at a density of 15 g fish L -1 for juvenile S. brasiliensis with an average weight of 0.71 g. The absence of mortality during transportation found in this study was also recorded for pirarucu (Arapaima gigas), but with a shorter transportation time of 3 hours (Brandão, Gomes, Crescêncio, & Carvalho, 2008). Therefore, the present study can contribute to the success of fish farming programmes of juvenile pacamã using long-term transportation.…”

“…The result of our study reveals the need for other studies of juvenile L. alexandri that evaluate higher densities and longer transportation times associated with different water temperatures. In the transportation of juvenile dourado Salminus brasiliensis at different densities (5, 10, and 15g L -1 ) and times up to 12 hours duration, the pH and dissolved oxygen were not affected, but increased fish density resulted in higher ammonia levels at the end of the transportation (Adamante, Nuñer, Barcellos, Soso, & Finco, 2008). The survival rate immediately after 11 hours transportation was 100% for all treatments (Table 2).…”

<b>Water quality and survival rate of <i>Rhamdia quelen</i> fry subjected to simulated transportation at different stock densities and temperatures

“…These findings corroborate with Seidelin, Madsen, Byrialsen, and Kristiansen (1999), who reported that increased electric conductivity is due to loss of ions from the fish to the water during transportation in response to stressing factors. In a study on the transportation of Salminus brasiliensis, Adamante, Nuñer, Barcellos, Soso, and Finco (2008) reported an increase in the electric conductivity during the first hours of transportation at high stock density. Even with the possible loss of ions, the values observed in this study are probably within the normal range for this species, as high mortality rates were not found even though electric conductivity was increased.…”

Effect of propolis ethanol extract on myostatin gene expression and muscle morphometry of Nile tilapia in net cages

“…In spite of its advantages, production in net cages may induce stress in fish, due to the increased animal density per cubic meter of water (Adamante et al, 2008). However, several growth enhancers have been used to improve the muscle development of the animals through better nutrients in the diet and higher yield so that the negative effects of intensive production can be eliminated.…”