Net ion fluxes and ammonia excretion during transport of rhamdia quelen juveniles

• Autor(a) principal: Garcia, Luciano de Oliveira
• Data de Publicação: 2015
• Outros Autores: Barcellos, Leonardo José Gil, Baldisserotto, Bernardo
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da FURG (RI FURG)
• Texto Completo: http://repositorio.furg.br/handle/1/5677
• topic: Fish transport; Ionoregulation; load density; Transporte de peixes; Ionorregulação; Densidade de carga

The objective of this study was to verify net ion fluxes and ammonia excretion in silver catfish transported in plastic bags at three different loading densities: 221, 286 and 365g L-1 for 5h. A water sample was collected at the beginning and at the end of the transport for analysis of water parameters. There was a significant positive relationship between net ion effluxes and negative relationship between ammonia excretion and loading density, demonstrated by the following equations: Na+: y-24.5-0.27x, r2 =0.99, Cl- : y=40.2-0.61x, r2 =0.98, K+: y=8.0-27.6x, r2 =0.94; ammonia excretion: y=-11.43+0.017x, r2 =0.95, where y: net ion flux (mmol kg-1 h-1) or ammonia excretion (mg kg-1 h-1) and x: loading density (g). Therefore, the increase of loading density increases net ion loss, but reduces ammonia excretion during the transport of silver catfish, indicating the possibility of ammonia accumulation.