Growth performance, plasma and hepatic biochemistry of jundiá Rhamdia quelen fed dephytinized rice bran protein concentrate.

A 45-day feeding assay was carried out to evaluate the effects of crescent levels of dephytinized rice bran protein concentrate (DRBPC) on growth performance, nutrient deposition, plasma and liver parameters of jundiá Rhamdia quelen. Five experimental diets were formulated with inclusion of 0 (control), 10, 15, 20, and 30% of DRBPC. In total 500 jundiás (initial body weight 6.28 ± 0.12 g) were allocated in 20 tanks (230 L) to give four groups for each treatment. Fish were fed to apparent satiation for 45 days. Weight gain and specific growth rate were evaluated by cubic regression analysis (P < 0.05) and displayed maximal growth on the inclusion level of 25% of DRBPC. The results indicated that fish fed DRBPC15 and DRBPC30 had lower body protein deposition and hepatosomatic index compared to CONTROL diet, respectively. No significant differences (P > 0.05) were assessed in plasma parameters. The alanine aminotransferase activity was higher in fish fed DRBPC30 compared to CONTROL group. The present study has demonstrated that DRBPC displayed significant nutritional quality for the jundiá. Thus, this new ingredient could be included as a protein source in fish for minimizing the use of fish meal.

Fractionation of linseed and obtaining ingredients rich in protein and fibers: alternatives for animal feed.

BACKGROUND: Linseed fractionation was performed in laboratory scale to obtain concentrated protein and fiber fractions. Three methods were tested to obtain the linseed protein concentrate (LPC). The isoelectric pH method was more efficient in increasing the protein content and also provided higher yield. In the fractions obtained, the chemical composition (dry matter, ash, lipids, crude protein, total dietary fiber, calcium and phosphorus), total phenolic compounds and the physicochemical properties were evaluated. The profile of amino acids was determined for linseed meal and LPC, and the profile of monosaccharides was evaluated for linseed grain, soluble and insoluble fractions of the fiber. RESULTS: The results indicated that the protein concentration method by isoelectric pH improved the amino acidic profile and in vitro digestibility of LPC. The fractioning of the linseed fiber was efficient, since the soluble fiber of the soluble fraction corresponded to 675 g kg-1 . The separation of the fiber from the linseed concentrated the phenolic compounds in the insoluble fraction. For linseed grain there was a higher concentration of glucose, followed by xylose, galacturonic acid and arabinose. The same monosaccharides were identified in the insoluble fraction, with the exception of arabinose. In the soluble fraction, higher levels of xylose were found, followed by glucose, galacturonic acid and arabinose. CONCLUSION: The present study allows us to conclude that it is possible to separate the linseed into different fractions, obtaining a protection concentrate and fibers. The inclusion of these products in animal feed needs to be evaluated to determine levels of acceptance. © 2021 Society of Chemical Industry.

Linseed fibers modulate the production of short-chain fatty acids and improve performance and plasma and skin mucus parameters of silver catfish (Rhamdia quelen).

This study was conducted to evaluate the prebiotic action of distinct linseed fibers on diets for silver catfish (Rhamdia quelen) juvenile. For this, soluble and insoluble fractions of linseed fiber were concentrated separately and combined in four ratios (1:0.5, 1:1, 1:2, 1:4), which were added in diets and evaluated along with a control diet. After 45 days receiving the experimental diets, the animals were submitted to biometry for data collection and samples. The experimental design was completely randomized, data were submitted to analysis of variance, and the means were compared by Tukey's test (P < 0.05). Fish performance was higher for the group that received the 1:2 and 1:4 diets. The production of intestinal acetic acid was higher in fish fed on the 1:2 diet, and butyric acid was higher with 1:4 diet and the propionic acid with the control diet. The control diet led to lower counts of goblet cells. Total proteins and globulins in plasma, mucoprotein, total immunoglobulins, and cutaneous mucus pH were higher in fish fed on diets 1:2 and 1:4. Cortisol levels and intestinal pH were lower in these treatments. The linseed fiber intake increased total plasma immunoglobulins and plasma alkaline phosphatase activity and in mucus. It was concluded that the use of 1:2 and 1:4 soluble fiber/insoluble linseed in the diet beneficially modulates the production of short-chain fatty acids in the digesta, with reflection on growth performance, number of goblet cells in the intestinal epithelium, and improvement in plasma and skin mucus parameters of fish.

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

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.

Própolis em dietas para o jundiá / Propolis in diets for silver catfish

O objetivo deste estudo foi avaliar o uso da própolis como promotor de crescimento para o jundiá na fase inicial. Foram utilizados 450 juvenis de jundiá com 2,02 ± 0,55 g, alimentados com dietas contendo quatro níveis de própolis (0,5; 1,0; 1,5 e 2,0%), além de um tratamento controle (sem inclusão de própolis). Utilizou-se um sistema de recirculação de água, composto por 15 tanques (230 L de volume útil). Durante o ensaio experimental os parâmetros de qualidade da água foram mantidos em condições ideais para os peixes. Foram avaliados parâmetros de crescimento, proteína corporal, gordura corporal e glicose. Foi utilizado um delineamento inteiramente casualizado, com 5 tratamentos e 3 repetições. Os dados obtidos foram submetidos ao teste de normalidade e análise de variância. Quando a ANOVA foi significativa para as médias, aplicou-se o teste de Dunnet, utilizando o programa Statistical Analysis System®. Não foram observadas diferenças significativas (P>0,05) da suplementação de própolis na dieta sobre os parâmetros de crescimento. A quantidade de gordura corporal foi reduzida com a adição de própolis acima de 0,5%. Maior nível de glicose foi observado nos peixes alimentados com 2% de própolis na dieta. Conclui-se que a própolis testada na dieta não foi eficaz como promotor de crescimento para o jundiá.

The aim of this study was to evaluate the use of propolis as a growth promoter for South American catfish in the initial phase. Were used 450 jundiá juvenile with 2.02 ± 0.55 g, these were fed diets containing four propolis levels (0.5, 1.0, 1.5 and 2.0%), plus a control treatment (without inclusion of propolis). It was used a water re-use system, composed by 15 tanks (230 L). During the experimental test water quality parameters were maintained in optimal conditions for fish. It was evaluated growth parameters, body protein body fat and glucose. The DIC was used, completely randomized design with 5 treatments and 3 replicates. The data were submitted to normality tests and analysis of variance. When ANOVA was significant for the means, was applied the Dunnett test, using the program Statistical Analysis System®. Were not observed significant differences (P>0.05) of the propolis inclusion on growth parameters. The amount of fat was reduced with the addition of propolis above 0.5%. Increased glucose level was observed in the fish fed with 2.0% propolis in the diet. It was concluded that the propolis tested in the diet is not effective as growth promoter for the jundiá.