Sunflower protein concentrate and crambe protein concentrate in diets for silver catfish Rhamdia quelen (Quoy and Gaimard, 1824): use as sustainable ingredients

Abstract The objective of this study was to evaluate growth and metabolic parameters of silver catfish fed with protein concentrates of sunflower meal (SMPC) and crambe meal (CrMPC). The study evaluated two levels of substitution, where 25 or 50% of animal protein was replaced with plant-based protein. A total of 300 silver catfish (14 ± 0.26 g) were used in five treatments and three replications, in fifteen 280-liter experimental units. The results were submitted to analysis of variance and the means of the control diet was compared to the remaining treatments by Dunnett’s test at 5% significance level. At the end of the trial, no differences were observed for the variables final weight and daily weight gain. However, minor feed conversion was observed in the groups Control and SMPC-25%. Metabolic parameters were analyzed in the plasma and liver, where no significant differences were found for any of the blood parameters analyzed. In the analyzed liver parameters (ammonia, protein, amino acids and ALAT), the liver protein content was lower in fish consuming SMPC-50%, CrMPC-50% and 25% CrMPC diets. The amino acids content was higher in fish receiving the SMPC-25% diet. It can be concluded that sunflower meal protein concentrate is better utilized by fish and more efficient metabolically than crambe meal. This study demonstrated that a newly developed protein concentrate SMPC and CrMPC can effectively replace 25% and 50% the animal protein in a diet free of FM.

摘要 本研究旨在评估投喂葵花籽粕蛋白浓缩物（sunflower meal protein concentrate, SMPC）与亚麻荠粕蛋白浓缩物（crambe meal protein concentrate, CrMPC）的银鲶鱼的生长与代谢参数。本研究设置两个替代水平，即分别以植物蛋白替代25%或50%的动物蛋白。实验共使用300尾初始体重为14±0.26 g的银鲶鱼，设置5个处理组、3个重复，饲养于15个体积为280升的实验单元中。实验数据经方差分析处理后，以Dunnett检验在5%显著性水平下比较对照组日粮与其余处理组的均值。实验结束后，终体重与日增重两项指标未出现显著差异，但对照组与SMPC-25%组的饲料转化率更低。研究同时分析了血浆与肝脏中的代谢参数，所有检测的血液参数均未发现显著差异。在肝脏检测指标（氨、蛋白质、氨基酸与丙氨酸转氨酶（ALAT））中，投喂SMPC-50%、CrMPC-50%及25% CrMPC日粮的鱼群肝脏蛋白质含量更低；而投喂SMPC-25%日粮的鱼群肝脏氨基酸含量更高。综上，相较于亚麻荠粕蛋白浓缩物，葵花籽粕蛋白浓缩物更易被鱼体利用，代谢效率更高。本研究证实，本研究新开发的SMPC与CrMPC可在无鱼粉（fish meal, FM）日粮中有效替代25%与50%的动物蛋白。