Respostas fisiológicas de Podocnemis unifilis (tracajá), em fase juvenil, alimentos com rações comerciais de diferentes níveis proteicos

Abstract

Turtle farming is an alternative for food production with high nutritional value. The objective of the present study was to evaluate the physiological responses (hematological and biochemical) of juvenile of Podocnemis unifilis (yellow-spotted Amazon river turtles) fed with commercial rations with different crude protein (CP) levels during 180 days. A number of 120 animals were divided into four experimental groups (three replications), according to the amount of protein provided in the feeds (28, 32, 36 and 40% CP). Feed bromatological composition and the hematological parameters (hematocrit, hemoglobin concentration, erythrocyte count, burst, MCV and MCHC) and plasma biochemical parameters (glucose, total proteins, albumin, triglycerides and cholesterol) of yellow-spotted Amazon river turtles were analyzed after 60, 120, and 180 days of feeding. The ANOVA test was applied to the data, with respective post-tests according to the normality presented. The ration with 32% CP showed significantly higher values for dry matter, ash and phosphorus when compared to the other rations. Juveniles yellow-spotted Amazon river turtles that received ration with 28% CP, after 60 days, presented increase of the leukocyte respiratory activity (burst) in relation to the other groups. This group had significantly lower concentrations for cholesterol when compared to other groups evaluated at 60 days of feeding; and when comparing the different feeding periods for the group, reductions in total protein and glucose concentrations (P < 0.05) were observed between the 60 and 180 days feeding evaluations. The higher availability of mineral material from the ration with 32% CP may have influenced the transit of the food in the digestible tract of juvenile yellow-spotted Amazon river turtles, which may have led to the reduction of the MCHC and the triglycerides of the animals at 120 and 180 days, respectively, when compared to the other groups. The yellow-spotted Amazon river turtles that received ration with 32% CP also showed significant reductions in glucose, total protein, albumin and triglycerides when evaluated at different periods, at 120 or 180 experimental days. The 36% CP ration provided stability for total protein and cholesterol levels in the different periods. However, the animals fed with 40% of CP presented a significant improvement in erythrocytes number, lower oscillations for the leukocyte respiratory activity and stability to the glucose concentration. Thus, commercial feed with similar composition to the one used in the present study, that with 36% of CP, can be recommended to feed juvenile yellow-spotted Amazon river turtles for the best cost benefit during farming, since higher levels may increase the production cost