Vitamina A em dieta de juvenis de pacu cultivados em tanques-rede

Abstract

O objetivo deste trabalho foi avaliar o efeito da suplementação de vitamina A na alimentação de juvenis de pacu cultivados em tanques-rede. Foram utilizados 2.000 peixes, com peso inicial médio de 66,93±15,03 g, distribuídos em delineamento inteiramente casualizado, em 20 tanques-rede de 5,0 m³, com cinco tratamentos e quatro repetições. As rações foram formuladas com 0, 3.000, 6.000, 9.000 e 12.000 UI de vitamina A por quilograma de dieta, por meio da suplementação com acetato de retinol. O arraçoamento foi realizado às 8:30, 13:30 e 17:30 h, até a saciedade aparente dos animais. Não foram observadas diferenças quanto aos parâmetros de desempenho produtivo, rendimento e composição química da carcaça, e aos parâmetros hematológicos e lipídios no fígado dos peixes que foram alimentados com diferentes níveis de vitamina A. A suplementação de vitamina A em dietas para juvenis de pacu criados em tanques-rede não influencia o desempenho produtivo dos peixes.

Vitamina a Na Dieta De Alevinos De Pacu

“…Studies that evaluated vitamin A dose responses report that mortality is common when there is a vitamin A deficiency in the diets (ORNSRUD et al, 2002;HU et al, 2006;PEIL et al, 2007;CAMPECHE et al, 2009). In this study, the presence or absence of vitamin A supplementation in the diet did not interfere with the survival of pacus, which corroborates the data observed by SIGNOR et al (2013) in the same species. Likewise, GUO et al (2010) did not observe an effect of vitamin A supplementation in the diet on the survival of tilapia fingerlings; these authors observed 98.57% survival in fish that received a diet without vitamin A supplementation.…”

“…Therefore, the authors indicated that further research was needed to evaluate the influence of vitamin A on growth performance in pacu. On the other hand, BUENO et al (2008) reported that the environment used by the researchers in that study (SIGNOR et al, 2013) was oligotrophic, which may have compromised the study results. Knowledge about the effects of vitamin A on fish growth is essential for de designing of diet formulations that meet the nutritional requirements of fish (NRC, 2011).…”

“…We observed a quadratic effect in weight gain and apparent feed conversion as a function of the vitamin A supplementation in the diet, demonstrating that vitamin A influences the metabolism and consequently the productive performance of fish. The fact of SIGNOR et al (2013) evaluated different levels (0; 3,000; 6,000; 9,000, and 12,000 UI vitamin A per kilogram of diet) of vitamin A in pacu cultivated in cages and did not observe differences in weight gain may be related to the short period of cultivation in that study; the authors of that study explained that this short period of cultivation did not allow the observation of negative effects related to a lack or excess of vitamin A in the diet. It can be inferred that in the study by SIGNOR et al (2013), the fish consumed natural microorganisms from the culture environment, which complemented the nutritional requirement because that was an oligotrophic environment (BUENO et al, 2008;BARBIERI and BONDIOLI, 2015).…”

“…However, nutrients can be required in up to 10 times more under conditions of diseases, stress, and social interactions than under normal culture conditions (TOGUYENI et al, 1997). SIGNOR et al (2013) used retinyl acetate Microvit TM A Supra 1000 as the source of vitamin A (0; 3,000; 6,000; 9,000 and 12,000 UI of vitamin A for kg diet) to supplement diets for pacu (66 grams of initial weight) and showed no influence on productive performance in fish cultivated in cages. However, the authors evidenced the need for more research aimed at establishing the requirement of vitamin A in this species.…”

Opportunities and challenges for fish culture in Brazilian reservoirs: a review

“…In the same location (Itaipu reservoir), Hilbig et al (2012) suggested a decrease in 30% of the total feeding supply for Pacu production in a fish cage. Other studies that guarantee profitability of Pacu production in fish cages located in reservoirs have also been performed, approaching nutrition, production indexes and the minimum scale of Pacu farming (Silva et al, 2012;Signor et al, 2013).…”