Studies on carbon-13 turnover in eggs and blood of commercial layers

This paper aimed at evaluating the influence of diets containing different isotopic values of carbon-13 turnover on the half-life of egg (yolk + albumen), yolk and albumen individually, and blood of poultry using δ‰ 13C isotopic variation. Commercial layers fed four experimental isocaloric and isonitrogenous diets (RC 4, RC 3, RMC 4 and RMC 3) containing different isotopic values, during an experimental period of 56 days. Turnover of the studied tissues was influenced by the experimental diets. Blood and albumen were more influenced by dietary treatments as compared to egg and yolk. The RMC 3 diet induced better performance (better feed intake and higher egg production) due faster rate of carbon substitution than the RC 4 diet, and lower half-life for egg (yolk + albumen), yolk, and albumen

Methionine to cystine ratio in the total sulfur amino acid requirements and sulfur amino acid metabolism using labelled amino acid approach for broilers

Background[br/] Assuming that part of Methionine (Met) is converted into Cystine (Cys), but ignoring the rates with which such phenomenon occurs may lead to an excessive supply of Met in poultry diets. Such inconvenient could be easily avoided with the knowledge of the ideal Met:Cys/Total sulfur amino acids (TSAA) ratio and the rates of Met conversion into Cys.[br/] Results[br/] Met sources did not affect performance. Met:Cys/TSAA ideal ratio was determined using curvilinear-plateau regression model. Both optimum body weight gain and feed conversion ratio were estimated in 1007 g/day and 1.49, respectively, at 52% Met/TSAA ratio. Feed intake was not affected by Met:Cys/TSAA ratios. In the labelled amino acid assay, the rates with which Met was converted into Cys ranged from 27 to 43% in response to changes in Met:Cys/TSAA ratios, being higher at 56:44.[br/] Conclusion[br/] Based on performance outcomes, the minimum concentration of Met relative to Cys in diets for broilers from 14 to 28 d of age based on a TSAA basis, is 52% (52:48 Met:Cys/TSAA). The outcomes from labelled amino acid assay indicate that highest the Met supply in diets, the highest is its conversion into Cys

Rastreabilidade da farinha de carne e ossos bovinos em ovos de poedeiras comerciais pela técnica dos isótopos estáveis do carbono e nitrogênio Traceability of bovine meat and bones meal in eggs of commercial laying hens through carbon and nitrogen stable isotopes technique

Objetivou-se com este estudo rastrear a inclusão de farinha de carne e ossos bovinos em dietas para poedeiras comerciais, por meio da análise dos ovos e de suas frações (gema e albúmen), pela técnica dos isótopos estáveis do carbono e nitrogênio e avaliar o índice analítico mínimo detectável. Foram utilizadas 240 galinhas poedeiras da linhagem Shaver White de 73 semanas de idade, distribuídas em delineamento inteiramente casualizado, com cinco tratamentos e seis repetições. Foram avaliados cinco níveis de inclusão (0; 1,5; 3,0; 4,5 e 6,0%) de farinha de carne e ossos bovinos em uma dieta à base de milho e farelo de soja. No 35º dia, foram tomados aleatoriamente 24 ovos por tratamento: 12 serviram para amostragem de gema e albúmen e os outros 12 para amostragem do ovo (gema + albúmen). Os resultados isotópicos foram submetidos à análise multivariada de variância e, a partir das matrizes de erro, com 95% de confiança, foram determinadas elipses para identificar as diferenças entre os resultados obtidos com o fornecimento das dietas experimentais e a dieta controle, sem farinha de carne e ossos bovinos. No ovo e na gema, a partir do par isotópico da dieta com 3,0% de farinha de carne e ossos, houve diferenciação do par do tratamento controle, enquanto, no albúmen, a diferenciação ocorreu a partir do nível de 1,5% de farinha de carne e ossos bovinos na dieta. Pela técnica dos isótopos estáveis, é possível rastrear o uso de farinha de carne e ossos bovinos na alimentação de poedeiras; no albúmen, o nível mínimo de inclusão detectável é de 1,5% e, no ovo e na gema, 3,0%.<br>The objective of this study was to trace the inclusion of bovine meat and bones meal in diets of laying hens analyzing eggs and theirs fractions (yolk and albumen), by carbon and nitrogen stable isotopes, as well as to evaluate the detectable analytical minimal index. Two hundred and forty (240) Shaver White laying hens aging 73 weeks were distributed in a completely randomized design, with five treatments and six replicates. Five increasing levels (0; 1.5; 3.0; 4.5 and 6.0%) of bovine meat and bones meal in a diet based on corn and soybean meal were evaluated. On the 35th day, 24 eggs per treatment were randomly collected, twelve for yolk and albumen sampling and another twelve for egg (yolk + albumen) sampling. The isotopic results were analyzed in a multivariate analysis of variance. Through an error matrix (95% confidence) the ellipses were determined to identify the differences between results obtained with supply of experimental diets and control diet, without 3% bovine meat and bones meal. In egg and yolk, from the isotopes pair of the diet with 3% bovine meat and bones meal, there was differentiation in the pair of the control treatment, whereas in the albumen it was possible to detect the 1.5 bovine meat and bones meal. The stable isotopes technique is able to trace the use of bovine meat and bones meal in laying hens feed; the minimal traceable level of inclusion is 1.5% in the albumen and 3.0% in the egg and yolk

Efeito da linhagem e do nível de lisina da dieta sobre a qualidade da carne do peito de frangos de corte Effect of strain and dietary lysine level on breast meat quality of broiler chickens

O experimento foi conduzido com o objetivo de avaliar o efeito da linhagem e do nível de lisina da dieta sobre o rendimento e a qualidade da carne de peito de frangos de corte. Foram utilizados 2250 pintos não sexados, de três linhagens comerciais, identificadas como A, B e C, distribuídos em delineamento inteiramente casualizado em esquema fatorial 3x3 (linhagens e níveis de lisina), com cinco repetições de 50 aves. As aves receberam ração à vontade, à base de milho e farelo de soja, suplementadas com 1,18; 1,24 e 1,30% de lisina nas rações pré-iniciais (1 a 7 dias); 1,10; 1,16 e 1,22% nas rações iniciais (7 a 21 dias); 1,0; 1,06 e 1,12% nas rações de crescimento (21 a 35 dias) e 0,85; 0,91 e 0,97% nas rações de terminação (35 a 42 dias). Foram avaliadas as características de rendimento de peito e carne de peito e as medidas de espessura, largura, comprimento, pH, perda de peso por cozimento e força de cisalhamento da carne de peito. Para o rendimento de peito não foram observadas diferenças significativas, enquanto para rendimento de carne de peito houve efeito significativo da linhagem, em que a linhagem A apresentou o maior rendimento e a linhagem B, o menor. Para as medidas físicas da carne do peito, foram encontradas diferenças significativas entre as linhagens para comprimento de peito, com a linhagem C apresentando o maior resultado. O pH da carne diferiu significativamente para linhagens e níveis de lisina. As linhagens tiveram efeito sobre o rendimento, comprimento e pH da carne de peito, em que a linhagem A apresentou maiores valores para rendimento e pH e a linhagem C para comprimento.<br>The objective of this experiment was to evaluate the effect of broiler strain and dietary lysine level on breast meat yield and quality. Two thousand two hundred and fifty day old straightrun chicks from commercial strains named A, B and C were reared in a factorial 3x3 arrangement (strain and dietary lysine level) with five replicates of 50 birds per pen. The broiler chikens were feed ad libitun with a corn and soybean diet withing the following lysine levels: 1.18, 1.24 and 1.30% in pre-starter diets (1-7 days); 1.10, 1.16 and 1.22% in starter diets (7-21 days); 1.00, 1.06 and 1.12 % in grower diets (21-35 days) and .85, .91 and .97% in finishing diets (35-42 days). Total breast yield, breast meat yield, pH, breast measures (high, width and lenght), weight cooking loss, and breast meat shear force were evaluated. There were no effect of strain and diet on breast yield. Related to breast meat yield, strain A presented higher values than strain B. Strain C presented the highest breast lenght. There were effects of lysine level only for pH. pH was affected by strain and dietary lisine level. It was concluded that lysine level affected only pH value. Strain affected breast meat yield, lenght and pH, where strain A showed the highest values for yield and pH and strain C for breast lenght

Glutamina e turnover do carbono da mucosa intestinal de leitões desmamados Glutamine and carbon turnover of the intestinal mucosa of weaned piglets

Um experimento foi conduzido para verificar a influência da glutamina no turnover do carbono na mucosa intestinal de leitões desmamados. Nove matrizes receberam dietas compostas basicamente de plantas do ciclo fotossintético C4 durante toda a gestação (d&#8240;13C = 17,12) e lactação (d&#8240;13C = -19,26). Os leitões foram desmamados aos 21 dias de idade e 68 deles foram alimentados com ração composta de plantas do ciclo fotossintético C3 (d&#8240;13C = -25,12). Os leitões foram aleatoriamente distribuídos em duas dietas: uma sem suplementação de glutamina; e outra suplementada com 1% de glutamina. Aos 0; 1; 1,5; 2; 2,5; 3; 3,5; 4; 4,5; 5; 5,5; 8; 11; 15, 20; 29 e 46 dias pós-desmame, dois leitões de cada dieta foram abatidos para coleta de amostras da mucosa intestinal, que foram analisadas quanto à composição isotópica de d&#8240;13C e mensurada a velocidade de substituição do carbono no tempo. Os valores da meia-vida do carbono para a mucosa intestinal foram de 6,0 e 3,5 dias para as dietas controle e com glutamina, respectivamente. A glutamina acelerou a velocidade de substituição do carbono na mucosa intestinal, evidenciando sua ação benéfica na recuperação da estrutura do intestino após o desmame.<br>An experiment was carried out to evaluate the influence of glutamine on the carbon turnover in the intestinal mucosa of weaned piglets. Nine matrices received diets predominantly composed by photosintetic cycle C4 plants during the gestation (d&#8240;13C = -17.12) and lactation (d&#8240;13C = -19.26). The piglets were weaned at 21 days of age, and 68 animals were fed rations composed by photosintetic cycle C3 plants (d&#8240;13C = -25.12). The piglets were distributed at random in two treatments: one diet without glutamine supplementation and the other diet supplemented with 1% of glutamine. On days 0; 1; 1.5; 2; 2.5; 3; 3.5; 4; 4.5; 5; 5.5; 8; 11; 15, 20; 29 and 46 after weaning, two piglets from each diet were slaughtered for collection of samples of the intestinal mucosa which were analyzed for their isotopic composition in d&#8240;13C and the carbon substitution speed was measured, in terms of the time. The half-life values of the carbon for the intestinal mucosa were 6.0 and 3.5 days, in control and glutamine treatments, respectively. Glutamine accelerated the carbon substitution speed of the intestinal mucous membrane, evidencing its beneficial action in the recovery of the intestine structure after weaning