CRESCIMENTO E USO DE ADITIVOS NA PRODUÇÃO DE PIRAPUTANGA (BRYCON HILARII) E DOURADO (SALMINUS BRASILIENSIS)

Abstract

Additives that improve water quality, stimulate the immune system, and inhibit the growth of pathogens have been used as prophylactic measures in cultivation systems, to improve the animal's resistance to stressful management such as transport and bacterial infection. Thus, this study aims to understand the allometric growth and the use of additives in the production and transport of native fish. Article 1 identified the growth pattern of juvenile piraputangas (Brycon hilarii) in hapas of 8 m3 at a density of 20 fish/hapa, for 7 months. Biometric characteristics were measured every 30 days. The relative condition factor indicated good growth conditions for piraputangas with positive allometric growth, as well as all variables and correlations, except for weight x body width, standard length x head length, and standard length x body height. In article 2, the effects of the essential oil (EO) of basil clove (Ocimum gratissimum L.) (OG) in the transport water of piraputanga juveniles on the hematological profile, residual components of OE OG in plasma, fillet, liver, and quality of water. Transport (two hours) was in plastic packaging with doses of 10, 20, and 30 mg L-1 and a control group, in triplicate. Survival during and after transport was 100%. Oxygen levels remained high after transport and pH decreased in all treatments. After transport, hemoglobin, CHCM, HCM, and glucose increased in fish from the OE OG 30 mg L-1 group. The number of neutrophils increased in fish transported with EO OG 10 mg L-1. With increasing doses of OE OG, there was an increase in lymphocytes and compounds in plasma, fillet, and liver. A dose of 10 mg L-1 of OE OG in the transport of juveniles of Brycon hilarii is recommended for a two hours transport as it ensured fish survival, did not affect hematological parameters and the residue concentration was low. Article 3 investigated the potential of the bacterium Lactobacillus rhamnosos as a probiotic, paraprobiotic and their combination on growth performance, health status, and resistance of dourado (Salminus brasiliensis) infected with Aeromonas hydroplhila. The fish (6.78 ± 1.65 g and 8.97 ± 0.42 cm) distributed in 16 tanks (300 liters), at the density of 15 fish/tank received the treatments: diet without additive (control diet), probiotic (L rhamnosus 108 CFU), paraprobiotic (L. rhamnosus 1010 CFU) and synbiotic (probiotic L. rhamnosus 108 CFU + paraprobiotic L. rhamnosus 1010 CFU), for 45 days. Subsequently, the fish were challenged intraperitoneally with the bacterium A. hydrophila (0.82 x 106 CFU). The diets with paraprobiotic and synbiotic improved the condition factor of the fish about the control and the diet containing probiotic. In the hematological analysis the values of hemoglobin, hematocrit, and number of erythrocytes were reduced after the infection. There was a significant increase in leukocyte activity after infection, regardless of treatment. Diets supplemented with symbiotic and paraprobiotic provided greater total villi height and villi height compared to fish that received the control diet. The number of goblet cells was higher in fish that received diets containing symbiotic and probiotic and the diet. The cytoplasm area of hepatocytes from fish that received the paraprobiotic diet was higher. The diets with paraprobiotic (L. rhamnosus) and symbiotic (L. rhamnosus viable + inactive) showed potential height of the intestinal villi .The diets with paraprobiotic (L. rhamnosus) and synbiotic (L. rhamnosus viable + inactive) showed potential to improve the relationship between weight and length.