Uso da zeolita e do eugenol no transporte de juvenis de matrinxã (Brycon amazonicus)

Abstract

Brycon amazonicus, commonly known as matrinxa, is one of the most potential species for commercial fish farming in the Western Amazon. Nevertheless this is a very aggressive fish, and excessive movements in handling may lead animals to undesired consequences as body wounds, diseases or even mortality. The objective of this work was to evaluate zeolite in the transport in order to reduce excreted ammonia on water transport that may represent absence of one acute transport stressor. Additionally we evaluated the use an alternative anesthetic, eugenol, also in the transport water to tranquilize fish and together with zeolite increase the chances of the transport success. Three experiments were held: 1) matrinxã excreted ammonia in the transport water; 2) capacity of zeolite to absorb water ammonia; 3) Effects of zeolite and eugenol addition on the transport water on the metabolic stress responses of matrinxã. Water samples were taken during transport to measure temperature, oxygen, pH, ammonia and nitrite. Blood samples were also taken to measure hematrocrit, lactate, glucose, ammonia, protein, chlorides and sodium. Glycogen tissues contents were still measured. Transportation of fish during 4 h accumulated ammonia in the water in concentration of 1,39 mg/L, and pH 6,45±0,43, oxygen 13,5±0,24 mg/L and temperature 27,1±0,13°C. In the second experiment, zeolite in concentration of 7,5 mg/L absorbed properly ammonia transport water. In the third study zeolite and eugenol decreased metabolic stress responses of matrinxã to transport. Plasma glucose was around 65,62 mg/dL and cortisol 4,1 ng/dL.