-The objective of this work was to estimate requirements of digestible methionine + cystine for broiler chickens from 1 to 42 days of age. It was carried out four experiments for each one of the following phases: pre-initial, initial, growing and final. The birds were distributed in a completely randomized experimental design, with six treatments and six replicates. Treatments consisted of a basal feed for each phase, deficient in digestible methionine + cystine and supplemented with DL-methionine to supply six levels of digestible methionine + cystine, resulting in different digestible methionine + cystine:digestible lysine ratios. In the pre-initial phase, levels of digestible methionine + cystine did not influence feed intake and feed conversion. However, weight gain responded in a quadratic way. In the initial phase, levels of digestible methionine + cystine had decreasing linear effect on feed intake whereas weight gain and feed conversion were influenced in a quadratic manner. In the growth and final phases, feed intake was not influenced by levels of digestible methionine + cystine, but weight gain and feed conversion presented quadratic response. The levels of 0.873; 0.755; 0.748 and 0.661% of digestible methionine + cystine in the diet or the daily intake of 183; 575; 1,104 and 1,212 mg of digestible methionine + cystine are recommended for the pre-initial, initial, growth and final phases, respectively, which corresponds to the ratios of 71; 70; 76 and 72% of digestible methionine + cystine to digestible lysine.
The incorporation of polyunsaturated fatty acids in chicken eggs by adding oils to the diets has been extensively studied. This experiment aimed at evaluating possible changes in the fatty acid profile of the eggs of layers fed diets supplemented with linseed and soybean oils. The experiment was performed using 192 29 week-old laying hens, distributed in a completely randomized design, into six treatments with four replicates of eight birds each. Treatments consisted of a control diet (no vegetable oil) and diets including 2% of vegetable oil. Linseed oil replaced 0, 25, 50, 75, and 100% soybean oil in the diets, corresponding to 0.0, 0.5, 1.0, 1.5, and 2.0% of linseed oil in the diet. A pool of two egg yolks from each treatment was submitted to lipid extraction and fatty acid methylation, and subsequent gas chromatography (GC) analysis to detect seven fatty acids. Saturated (myristic and palmitic) fatty acids concentration was affected by lipid dietary source, with the lowest concentration in birds were fed feeds containing linseed oil. Polyunsaturated fatty acids (PUFA) concentration in the eggs was influenced by different levels of linseed oil inclusion. Linoleic acid egg content increased when linseed oil was used on diet as compared to the control diet. Linseed oil was considered an excellent source of linolenic acid incorporation in the eggs
RESUMOO objetivo do trabalho foi determinar o melhor nível de proteína bruta na alimentação de codornas japonesas em fase de produção. Foram utilizadas 300 codornas com 16 semanas de idade, alojadas em gaiolas, em um delineamento inteiramente casualizado, com cinco tratamentos, seis repetições e dez aves por unidade experimental. Os níveis avaliados foram 14, 17, 20, 23 e 26% de proteína bruta, e as dietas foram formuladas para serem isoenergéticas. Foi verificado efeito quadrático para consumo de ração, peso de ovo, massa de ovo, ingestão de energia, eficiência energética por dúzia de ovo, coeficiente de digestibilidade de nitrogênio, retenção de nitrogênio, peso de gema, casca e albúmen. Efeito linear foi verificado para produção de ovos, ingestão de proteína, conversão alimentar por massa de ovos, eficiência energética por massa de ovo em kg, peso final e gravidade específica. Não houve efeito significativo para conversão alimentar por dúzia e concentração sérica de ácido úrico. Recomenda-se nível de 20% de proteína bruta para codornas japonesas em fase de postura.
The aim of this study was to evaluate the effect of protein reduction and supplementation of l-glutamic acid in male broiler diets. A total of 648 chicks of the Cobb 500 strain were distributed in a completely randomized design with six treatments and six replications with eighteen birds per experimental unit. The study comprised pre-starter (1-7 days), starter (8-21 days), growth (22-35 days) and final (36-45 days) phases. The first treatment consisted of a control diet formulated according to the requirements of essential amino acids for each rearing phase. The second and third treatments had crude protein (CP) reduced by 1.8 and 3.6 percentage points (pp) in relation to the control diet respectively. In the fourth treatment, l-glutamic acid was added to provide the same glutamate level as the control diet, and in the last two treatments, the broilers were supplemented with 1 and 2 pp of glutamate above that of the control diet respectively. The reduction in CP decreased the performance of broilers and the supplementation of l-glutamic acid did not influence performance when supplied in the diets with excess of glutamate. The lowest excreted nitrogen values were observed in the control diet, and treatments 2 and 3, respectively, in comparison with treatments with the use of l-glutamic acid (5 and 6). Retention efficiency of nitrogen was better in the control diet and in the treatment with a reduction of 1.8 pp of CP. It was verified that the serum uric acid level decreased with the CP reduction. A reduction in CP levels of up to 21.3%, 18.8%, 18.32% and 17.57% is recommended in phases from 1 to 7, 8 to 21, 22 to 35 and at 36 to 42 days, respectively, with a level of glutamate at 5.32%, 4.73%, 4.57%, 4.38%, also in these phases.
The aim of this research was to determine the nutritional requirements of sodium for Japanese quail (Coturnix coturnix Japonica) during the periods of 1 to 21 d and 22 to 40 d of age, as well as to evaluate the residual effect on egg production and densitometry bone traits from 41 to 63 d. Two experiments were developed. Experiment 1: 360 Japanese quail were used, from 1 to 21 d of age. Treatments consisted of 5 sodium levels (0.06, 0.12, 0.18, 0.24, and 0.30%). Experiment 2: 240 Japanese quail were used, from 22 to 40 d. Treatments consisted of 5 sodium levels (0.04, 0.12, 0.20, 0.28, and 0.36%). In both experiments, weight gain, final weight, and feed conversion presented a quadratic trend, whereas water intake presented a linear trend. Treatments did not affect the densitometry of bone traits, although they presented a quadratic influence on tibia ash, calcium, and calcium:phosphorus ratio. Therefore, the nutritional requirement of sodium for Japanese quail from 1 to 21 d and from 22 to 40 d is 0.222% and 0.253%, respectively.
RESUMOO óleo essencial de erva-doce (OED) foi avaliado como alternativa aos antimicrobianos na ração de frangos de corte alojados em cama nova (CNo) e reciclada (CRe). Foram alojadas 1.050 aves, e adotou-se o delineamento inteiramente ao acaso, em que de um a 21 dias as aves foram mantidas somente em CNo, resultando em sete tratamentos com 10 repetições de 15 aves: T1= dieta controle positivo (CP) com antimicrobiano (ANT); T2= dieta controle negativo (CN) sem ANT e sem OED; T3= CN + 0,004% OED; T4= CN + 0,008% OED; T5= CN + 0,016% OED; T6= CN + 0,032% OED e T7= CN + 0,064% OED. De 22 a 42 dias, metade das aves foram criadas em CRe, e a outra metade em CNo, resultando em 14 tratamentos com cinco repetições de 15 aves. O OED foi adicionado pela manhã, na proporção de 1/4 do consumo diário da dieta, e, na parte da tarde, o fornecimento foi à vontade. Na fase pré-inicial, a inclusão de 0,015 e 0,026% de OED melhorou o consumo de ração e o ganho de peso, respectivamente. A inclusão de 0,031% de OED melhorou a conversão alimentar dos frangos de um a 21 dias. O OED promoveu maior peso de carcaça de aves alojadas em CNo, maiores pesos de coxa, sobrecoxa e rendimento de sobrecoxa de frangos criados em CRe. O OED melhorou o desempenho de frangos alojados sob condições de CRe. (Silva et al., 2007).A substituição total da cama a cada lote de frangos, embora possa ser considerada ideal sob o aspecto de preservação da saúde animal, resulta
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