A 70-days feeding trial was performed to determine the effect of diets with whole plant-origin proteins added with different ratios of taurine:methionine on the growth, macrophage burst activity and antioxidant capacity of rainbow trout (Oncorhynchus mykiss) fingerlings. Triplicated groups of 70 fingerlings of an initial weight of 0.54±0.1 g (mean±±SD) were fed diets with soy protein isolate and Spirulina powder as protein sources (46% crude protein) and added (10 g/kg diet) with different taurine and methionine ratios: 0.0 and 10.0 (diet T0/M100), 2.5 and 7.5 (diet T25/M75), 5.0 and 5.0 (diet T50/M50), 7.5 and 2.5 (diet T75/M25) and 10.0 and 0.0 (diet T100/M0), respectively. At the end of the trial, growth performance, lipid and protein contents in liver and muscle, macrophage burst activity and liver antioxidant activity, were determined. The growth performance, macrophage burst activity and antioxidant activity were improved as the taurine increased in the diets. The ratio of 7.5 and 2.5 g/kg of taurine:methionine in diets with SPI and Spirulina powder as protein sources (diet T75/M25), seems to be the best inclusion for rainbow trout fingerlings.

<!--Galleys --> <!--Full Text:--> PDF <!--END GALLEYS---> Abstract This study aimed to evaluate the effects of mushroom meal supplementation, Pleurotus djamor var. roseus (Pd), on the diet of Nile tilapia (Oreochromis niloticus), on hematological parameters and growth performance for 60 days. Nile tilapia fingerlings (3.23 ± 0.19 g) were fed with three experimental diets based on the mushroom meal in different percentages: diet 0% control (MM0), diet 15% (MM15), diet 20% (MM20) and diet 25% (MM25). Blood samples from the fish of all treatments were collected at the start of the experiment (day 0), 30 and 60 days. The weight and size of the fish were determined every 15 days (0, 15, 30, 45 and 60 days). The results showed a significant dose-dependent increase in the levels of erythrocytes count and leukocytes count. The groups that showed significant differences in the basal value and the final control result were hematocrit, hemoglobin, and lymphocyte. An increase in lymphocytes proportion and a decrease in neutrophils were found, which was related to the immune response of fish fed the diet. The highest levels of leukocytes, lymphocytes, and low neutrophils were presented in the diet with 15 and 20% (P < 0.05). The growth (weight gain and specific growth rate) of fish fed MM15 and MM20 of Pd in the diet was higher than the control group (P > 0.05). Dietary supplementation (15 and 20%) improved hematological and defense blood cells, as well as the growth of tilapia.

Contribución al conocimiento de los requerimientos nutricionales del langostino nativo (Macrobrachium acanthurus )