Glicerina bruta em dietas de juvenis do híbrido “pintado-da-amazônia” (fêmea pseudoplatystoma punctifer x macho leiarius macho leiarius marmoratus)

Abstract

The production of biodiesel has been accompanied by the increase of by-products, among which crude glycerin, which has been the subject of numerous researches in which its use as an energy source for feed of production animals is highlighted. The present study aimed to establish the values of zootechnical performance, body composition, hematological parameters, biochemical parameters and histopathological analysis of juveniles of "Painted-of-Amazonia" after feeding with rations containing increasing levels of crude glycerin. The experiment was carried out at theNeotropical Fish Morphophysiology and Biochemistry Laboratory of the Federal University of Tocantins, 150 juveniles of Amazonian Paints, with initial weight of 6.83 ± 1.11 (g) and length of 10, 06 ± 0.57 cm distributed in a completely randomized design (DIC), with 3 replicates (10 animals in each replicate). The animals were fed five diets with increasing levels of glycerol (0%, 5%, 7.5%, 10% and 12.5%) and fed for a period of 90 days (30 days of adaptation and 60 experimental days). At the end of this period, the animals were used to measure their performance (length and final weight, survival, specific growth rate, hepatosomatic index, condition factor, weight gain, conversion and feed efficiency). de insensitized in the ice to perform the analysis of fish body composition, according to the standard methodology described by INCT (2012). Hematological parameters were determined: hematocrit, hemoglobin, erythrocyte count, and hematocrit indices: VCM (mean corpuscular volume), HCM (mean corpuscular hemoglobin) and CHCM (mean corpuscular hemoglobin concentration) and for biochemical analysis: total protein concentration, total cholesterol, triglycerides, Aspartate Amino Transferase (AST) and Enzyme Alanine Amino Transferase (ALT), hepatic, muscle glycogen and blood glucose. Histopathological analyzes of the liver and kidney of the animals were also performed. The specific growth rate showed moderate linear behavior and muscle glycogen at the level of 12.5% presented a lower concentration in relation to the control diet (0.0%). As for histology, crude glycerin did not cause significant hepatic and renal changes in the studied species, since the alterations found in the two tissues were considered lesions that did not compromise the functioning of the organ or reversible lesions. Finally, the juveniles of Painted Amazonian are able to metabolize the crude glycerin up to the level of 10.0%. Since, until this level, no significant changes were observed in the zootechnical, body composition, hematological, biochemical and histological parameters of the animal.