Nutritional composition of larvae of mealworm (Tenebrio molitor L) and crickets (Gryllus assimilis) with potential usage in feed / [Composição nutricional de larvas de Tenebrio molitor e de grilos (Gryllus assimilis) com potencial de uso na alimentação animal]

Atualmente, tem-se discutido a utilização de insetos na alimentação animal devido ao seu potencial para substituir as fontes tradicionais de proteína utilizadas. O objetivo deste trabalho foi determinar a composição nutricional de larvas de Tenebrio molitor e de grilos do gênero Gryllus assimilis. Os teores de energia bruta (kcal/kg), proteína bruta (g/kg), extrato etéreo (g/kg), cinza (g/kg), FDN (g/kg) e FDA (g/kg) encontrados nas larvas de Tenebrio molitor foram de 7.188,6, 490,2, 335,4, 36,8, 71,8, e 64,0 respectivamente; nos grilos (Gryllus assimilis), os valores foram de 5.942,6, 541,3, 75,2, 49,1, 277,8, e 193,0 respectivamente. Os macros e microminerais quantificados foram fósforo, potássio, sódio, cálcio, magnésio, ferro, manganês, zinco e cobre. Nas larvas de Tenebrio molitor, os valores encontrados foram de 8,56 g/kg, 8,39 g/kg, 1,39 g/kg, 0,44 g/kg, 2,3 g/kg, 48,4 mg/kg, 15 mg/kg, 189 mg/kg e 18 mg/kg respectivamente. Para os grilos (Gryllus assimilis), os teores encontrados foram respectivamente de 8,30 g/kg, 11,6 g/kg, 1,10 g/kg, 3,88 g/kg, 0,82 g/kg, 96,8 mg/kg, 23,7 mg/kg, 18,3 mg/kg e 21,7 mg/kg. Larvas de Tenebrio molitor e grilos do gênero Gryllus assimilis podem ser alternativas para reduzir o uso de fontes de proteína vegetal na alimentação animal.(AU)

Effects of free and dipeptide forms of methionine supplementation on oxidative metabolism of broilers under high temperature.

Our previous studies have shown that methionine supplementation could help to attenuate the effects of heat stress on the metabolism of broiler chickens. Here we investigated for the first time the effects of methionine supplementation in the form of DL-methionyl-DL-methionine on broilers subjected to heat stress during the growth phase. Broilers were divided into two groups; one group was reared under thermoneutral conditions and the other under continuous heat stress (30 ±â€¯1 °C, 60% relative humidity). Both groups were subdivided into three dietary treatments: a methionine-deficient (MD) diet, a diet supplemented with free methionine (DL-M), and a diet supplemented with methionine dipeptide (DL-MM). Broilers raised under chronic heat stress had lower feed intake and weight gain than broilers raised under thermoneutral conditions (P < 0.05). There were no differences in animal performance between methionine-supplemented diets (DL-M and DL-MM). Heat-stressed birds had significantly higher heterophil/lymphocyte (H/L) ratio than thermoneutral birds. Under heat stress, broilers fed DL-M and DL-MM diets had lower H/L ratio than birds fed the MD diet. Higher concentrations of carbonylated proteins and lower concentration of reduced glutathione were observed in broilers raised under heat stress. In comparing heat-stressed broilers, we found that birds fed the DL-M diet had lower concentrations of thiobarbituric acid-reactive substances and carbonylated proteins than those fed the MD diet (P < 0.05). Higher expression of glutathione peroxidase (GPX) and glutathione synthetase (GSS) genes was observed in heat-stressed broilers (P < 0.05). Under heat stress, the MD diet increased GPX expression compared with other diets. Under thermoneutral conditions, the DL-M diet resulted in the highest GSS expression. There was a negative correlation between DNA methylation and GPX and GSS expression. Our results showed that supplementation of broiler diets with free methionine or methionine dipeptide may help attenuate the effects of heat stress through enhanced activation of genes related to the glutathione antioxidant system. Methionine effects were found for gene regulation, gene expression, and post-translational processing.

Relação zinco cobre em dietas de codornas japonesas em postura / Zinc copper ratio of Japanese quails diets posture

Objetivou-se verificar o efeito da suplementação de diferentes relações de zinco orgânico e de cobre inorgânico, bem como comparar os resultados com a dieta controle de codornas japonesas, sobre o desempenho produtivo e a qualidade dos ovos. Foram realizados dois experimentos na área experimental da Universidade Federal do Espírito Santo: variando os níveis de zinco orgânico e mantendo os de cobre recomendados e outro variando os níveis de cobre inorgânico. O período experimental foi de 84 dias, divididos em períodos de 21 dias. Foram usadas cinco pré-misturas minerais. Foram analisadas variáveis de desempenho e qualidade dos ovos. Foi observado primeiramente que as variáveis avaliadas não foram afetadas de forma significativa pelas diferentes relações dos minerais, exceto para pesos relativo e absoluto da casca. No segundo ensaio, não houve interação entre os níveis de zinco e de cobre nem entre estes e a dieta controle, para nenhuma das variáveis observadas; quando analisadas as médias individuais, foi observada diferença significativa para taxa de postura, relação ovos comerciais e totais, consumo de ração e na unidade Haugh. Pode-se concluir que a relação de 35mg/kg de zinco orgânico e a de 3,5mg/kg de cobre inorgânico atenderam as necessidades nutricionais dos animais para desempenho e qualidade de ovos.(AU)

The objective of this study was to verify the effect of the supplementation of different organic zinc and inorganic copper ratios and to compare the results with the Japanese quail control diet on the productive performance and egg quality. Two experiments were carried out in the experimental area of the Federal University of Espírito Santo, varying the levels of organic zinc and maintaining the recommended copper and the other varying levels of inorganic copper. The experimental period was 84 days. Five mineral premixes were used. Performance and egg quality variables were analyzed. It was first observed that the evaluated variables were not affected significantly by the different mineral relations, except for relative and absolute weight of the bark. In the second test, there was no interaction between the zinc and copper levels, neither between the control and the control diet, for any of the variables observed, when analyzing the individual means, a significant difference was observed for posture rate, commercial and total eggs ratio, feed intake, and in the Haugh Unit. It can be concluded that the ratio of 35mg/kg organic zinc and 3,5mg/kg of inorganic copper met the nutritional requirements of the animals for performance and egg quality.(AU)

Effect of dietary lysine on performance and expression of electron transport chain genes in the pectoralis major muscle of broilers.

The aim of this study was to evaluate the effect of dietary lysine on performance, protein deposition and respiratory chain gene expression in male broilers. A total of 252 Cobb 500 broilers were distributed, in a completely randomized design, into four treatments with seven replicates of nine birds per experimental unit. Experimental treatments consisted of diets based on corn and soybean meal, with four levels of digestible lysine: 1.016%, 1.099%, 1.182% and 1.265%. The increase in the level of digestible lysine in the diet provided higher weight gains, feed efficiency and body protein deposition. Birds fed the lowest level of dietary lysine (1.016%) showed a lower expression of genes such as NADH dehydrogenase subunit I (ND1), cytochrome b (CYTB) and cytochrome c oxidase subunits I (COX I), II (COX II) and III (COX III), displaying the worst performance and body protein deposition. This demonstrates the relationship existing between the expression of the evaluated genes and the performance responses. In conclusion, results indicate that broilers fed diets with higher levels of digestible lysine have increased messenger RNA expression of some genes coded in the mitochondrial electron transport chain (ND1, CYTB, COX I, COX II and COX III). It may be stated that diets with proper levels of digestible lysine, within the 'ideal protein' concept, promote the expression of genes, which increases the mitochondrial energy, thereby fostering body protein deposition and the performance of broilers in the starter phase.