Fontes de óleos vegetais na dieta de rã-touro (Lithobates catesbeianus): composição centesimal e ácidos graxos

Abstract

The production of frogs in Brazil reached 200 tons, and shows a stagnation since 2016. The present study aimed to analyze the proximate composition and fatty acids present in the thigh muscles of bullfrogs (L. catesbeianus) fed with different sources of vegetable oils (sunflower, olive, corn and soybean oils). 96 juvenile frogs were housed in 12 plastic boxes with a volume of 70 liters containing 8 animals per experimental unit, in a completely randomized design, divided into 4 treatments and 3 replications. The experiment lasted 61 days, and a commercial fish feed with 40% protein and 2% inclusion of each oil source was offered. The animals received the diet at 3% of body weight per day, divided into 4 meals. The correction of the ration rate took place every 20 days. At the end of the experimental period, all animals were weighed, measured and counted, and three specimens from each box were slaughtered. Proximate composition and fatty acid analysis were performed. There were statistical differences for the analysis of moisture, protein and lipids (P<0.05) of the frogs' thigh meat, but the ash was not altered as a function of vegetable oil. As for the fatty acids from the frog's thigh, the animals that received olive oil had higher amounts of saturated, monounsaturated, polyunsaturated fatty acids and in the sum of total fatty acids. In the analysis of the main components, soybean oil when compared to olive oil behaved similarly, thus, the best oil to be used would be soybean oil due to the cost and availability of the product. The use of different sources of vegetable oils in the diet of bullfrogs (L. catesbeianus) influences both the proximate composition and the fatty acid composition.