Óleo essencial de orégano como promotor de crescimento para lambaris-do-rabo-amarelo (Astyanax altiparanae)

• Autor(a) principal: Ferreira, Pollyanna de Moraes França
• Data de Publicação: 2012
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/2254
• topic: Carvacrol; Extratos vegetais; Lambari; Origanum vulgare; Timol; Carvacrol; Vegetable extracts; Astyanax altiparanae; Origanum vulgare; Thymol; CNPQ::CIENCIAS BIOLOGICAS::ZOOLOGIA

The growth promoters are substances, natural or synthetic, or living organisms added to the diets that increasing the weight gain, improve feed and reproductive efficiency, as well as decrease the mortality of animals. Among the classes of growth promoters, essential oils are noted to be natural substances and safe from the standpoint of health of animals, humans and the environment. Among the essential oils with potential to be used as growth promoter there is oregano oil, Origanum vulgare, due to its antibacterial, antioxidant, antifungal, anti-inflammatory, anthelmintic properties and stimulant of digestion. Its properties are attributed to the presence of phenols carvacrol and thymol and the monoterpenes γ-terpinene and ρ-cymene, among others. Thus, the present study aimed to evaluate the effects of oregano oil on growth performance, energy metabolism and chemical composition of the carcass of Astyanax altiparanae. The fish (1.46 ± 0.09 g) were distributed into 24 aquaria containing 60 liters of water, at the stocking density of 0.5 fish L-1. The experimental design was completely randomized with six treatment and four repetitions, where it were evaluated six isonitrogenous (350 g CP kg-1) and isoenergetic (4.272 kcal GE kg-1) practical diets containing 0.0, 0.5, 1.0, 1.5, 2.0 and 2.5 g of oregano essential oil kg-1. Fish were fed to satiation, three times a day, during 90 days. The following parameters were evaluated for yield performance: the survival rate (SR), weight gain (WG), feed intake (FI), feed conversion ratio (FCR), protein efficiency ratio (PER), specific growth rate (TEC), body condition factor (K), final length (FL), carcass weight (CW), carcass yield (CY) and viscerossomatic index (VSI). The parameters of energy metabolism evaluated were: blood glucose, liver and muscle glycogen. It were also evaluated the dry matter, crude protein, ether extract and ash of the fish carcass. The assessment of the effects of oregano oil on the evaluated parameters was performed through analysis of variance and polynomial regression at level of 10% probability. A quadratic effect of oregano oil levels in the diet were observed for weight gain, specific growth rate, protein efficiency rate and carcass weight, and the estimated values for maximize these parameters was between 0.2-0.6 g kg-1. There was also a significant effect on feed convertion ratio and the estimated value for minimize this variable was 0.62 g kg-1. Decreased linearly effect was observed for the final length. There was no significant effect of oregano oil on blood glucose and liver glycogen, but increasing linear effect was observed for muscle glycogen. There was no effect of levels of oregano oil for the ashes of the carcass. There was linear decrease effect of the oregano oil levels for dry matter and ether extract of the carcass. For crude protein carcass was observed a quadratic effect of oregano oil levels, and the estimated value to maximize this parameter was 0.79 g kg-1. Thus, it can be conclude that the essential oil of oregano in diets for Astyanax altiparanae can act as growth promoter, influence energy metabolism and chemical composition of the carcass.