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.

The Effects of Fermentable Dietary Fiber on Performance and Metabolism of Nile Tilapia (Oreochromis niloticus)

Abstract This study was conducted to evaluate the inclusion of new prebiotics in the diet on performance and metabolism (liver protein, glucose and glycogen) of Nile tilapia. For 60 days, 720 Nile tilapia (3.4 ± 0.60 g) were maintained in 24 polypropylene tanks (280 liters). Fish were fed with experimental diets with addition of 2.5 and 5 g kg-1 of dietary fiber of citrus pulp (DFCP), dietary fiber of linseed (DFL) and Actigen®. The experimental design was completely randomized with a 3x2 factorial arrangement. At the end of the period, there was higher final weight of tilapias fed on diets containing DFCP and DFL, and regardless of prebiotic, the best results in the final weight and length were observed for inclusion of 2.5 g kg-1. There was higher body protein deposition in tilapia fed on diets containing DFCP, without differences from those with inclusion of DFL. Total fat deposition was higher for the lowest level of inclusion (2.5 g kg-1). The digestive somatic index was higher for the diet with inclusion of DFCP, which did not differ from the diet with inclusion of Actigen®. There were higher concentrations of liver glycogen in the diets containing DFCP and Actigen®. Faced with the search for alternative growth promoters, this study confirms the possibility of using the new prebiotics (DFCP and DFL) in nutrition of Nile tilapia, because they showed efficiency equivalent to the prebiotic Actigen®.

Nutritional evaluation of phosphorylated pumpkin seed (Cucurbita moschata) protein concentrate in silver catfish Rhamdia quelen (Quoy and Gaimard, 1824).

An 8-week feeding trial was conducted to evaluate the effect of replacing fish meal with pumpkin seed meal (PSM) or phosphorylated protein concentrate of pumpkin seed meal (PPCPS) on growth and metabolic responses of silver catfish. Five isonitrogenous and isocaloric diets were formulated. Control diet contained fish meal as the main protein source. The treatment groups contained 25 and 50% of either PSM or PPCPS protein replaced the fishmeal protein. A total of 400 silver catfish, with initial mean weight of 24 ± 0.46 g, were distributed into 20 tanks. For data four orthogonal contrasts were applied: control diet versus PSM diets; control diets versus PPCPS diets; control versus other diets; PSM diets versus PPCPS diets. The results indicated that the fish fed PSM diets had lower weight gain when compared to either control diet or PPCPS. The PPCPS do not affect growth and protein efficiency ratio. Lower albumin contents were found for the control diet fish for the contrasts control diet versus PPCPS diet and control diet versus other diets. The hepatic ALAT enzyme activity was higher in the fish fed the control diet (P < 0.05). The hepatic ALP was most active in fish that received the PPCPS diets, when comparing control diet versus PPCPS diets and control diet versus other diets. The hepatosomatic index was higher for fish fed the PPCPS. Our results indicated that PPCPS presents relevant nutritional quality for fish and can replace the fish meal protein up to 50% without affecting growth, PER and intermediate metabolites in silver catfish.

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.