Obtenção do concentrado proteico de linhaça e sua aplicação na nutrição do jundiá

• Autor(a) principal: Pianesso, Dirleise
• Data de Publicação: 2018
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Manancial - Repositório Digital da UFSM
• dARK ID: ark:/26339/00130000173dp
• Texto Completo: http://repositorio.ufsm.br/handle/1/15646
• topic: Rhamdia quelen; Concentração proteica; Proteína vegetal; Linum uistatissimum L; Protein concentration; Vegetable protein; CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA

The objective of this study was to evaluate the effects of diets containing increasing levels of fish meal (FM) protein replacement by linseed protein concentrate (LPC) on growth, nutrient deposition, somatic indexes, digestive enzymes activity, metabolic responses and counting of goblet cell in silver catfish (R. quelen). The LPC obtained by means of the isoelectric pH of the amino acids presented lower protein content (P<0.05) but higher protein digestibility (P<0.05) than fish meal. Subsequently, the LPC was included in levels (0, 10, 20, 30 or 40%) of substitution of the FM protein in the diets. During 60 experimental days, 500 jundias, with initial mean weight of 6.13 ± 0.97 g were distributed in 20 tanks (70L), fed five experimental diets in four replicates. For statistical analysis, the data were submitted to normality test (Shapiro-Wilk), variance analysis (ANOVA), and the means were compared by Tukey test (5% significance) and correlation analysis. Were evaluated growth performance, somatic indexes, body nutrient deposition, trypsin and chymotrypsin digestive enzyme activities, as well as metabolic parameters in plasma and liver besides, goblet cell counts. The replacement of FM protein by LPC did not significantly influence (P>0.05) the productive parameters of body deposition and somatic indexes the fish. There was a positive correlation (P<0.05) between the growth variables (weight gain, length, specific growth rate, relative weight gain and final biomass) and the somatic digestive index, but feed conversion apparent presented a negative correlation (P<0.05) with this same variable. When the FM protein was replaced by 30 or 40% LPC in the diet, there was an increase (P<0.05) in the activity of the chymotrypsin enzyme, differing from fish those fed the 0% LPC diet. Serum albumin levels were higher (P<0.05) in fish fed with the diet in which 20% of the FM protein was replaced by LPC, compared to treatments 10 and 30% LPC. Diets containing higher levels (30 or 40%) of LPC in substitution of the FM protein promoted a higher (P<0.05) concentration of free amino acids in plasma. Replacement of FM protein by 30% LPC promoted a higher (P<0.05) concentration of hepatic protein differing from treatment without substitution of FM protein. Hepatic ammonia was higher (P<0.05) in fish fed the 0% LPC diet, without differing from treatments 10 and 40% LPC. There was an increase in the goblet cell count with the replacement of 30% of the FM protein by LPC in the diet, when compared to the treatment without the addition of LPC (P<0.05). Thus, it can be concluded that LPC presents nutritional quality to replace fish meal protein in up to 40%, as it does not alter the growth, efficiency of protein and fat utilization for body deposition and may promote beneficial effects on cell renewal the intestinal.