Digestible methionine+cysteine in the diet of commercial layers and its influence on the performance, quality, and amino acid profile of eggs and economic evaluation
| Autor: | Diego Pereira Vaz, Nelson Carneiro Baião, Lorena Salim de Sousa, Mariana Masseo Saldanha, Leonardo José Camargos Lara, M.V. Triginelli, T.S.M. Carvalho, M.F.V.S. Pinto, Flávia Aparecida Nogueira |
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| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
Cost-Benefit Analysis Feed conversion ratio 03 medical and health sciences chemistry.chemical_compound Random Allocation Animal science Methionine Valine Animals Proline Cysteine Eggshell Amino Acids Ovum chemistry.chemical_classification Dose-Response Relationship Drug 0402 animal and dairy science 04 agricultural and veterinary sciences General Medicine 040201 dairy & animal science Animal Feed Amino acid Diet 030104 developmental biology chemistry Dietary Supplements Animal Science and Zoology Female Isoleucine Leucine Chickens |
| Zdroj: | Poultry science. 97(6) |
| ISSN: | 1525-3171 |
| Popis: | This work aimed at evaluating the effects of 4 digestible Met+Cys levels on the diet of commercial layers and their influence on the productive performance, quality, and amino acid profile of eggs and economic viability of the activity. A total of 576 white Lohmann LSL-Lite layers was distributed into 6 replicates of 24 birds for each diet. The experimental design was completely randomized, with 4 treatments defined by levels evaluated in the feed (0.465, 0.540, 0.581, and 0.647%). The productive performance was measured for 30 weeks. The quality (34 and 50 wk old) and the amino acid profile of eggs (43 wk old) also were evaluated. A linear positive response was observed at higher Met+Cys levels for feed intake, number of eggs per housed bird, and digestible Met+Cys intake. Egg production, egg weight, egg mass, feed efficiency, and weight gain had their optimal values determined by the quadratic regression model at 0.638, 0.654, 0.647, 0.644, and 0.613% digestible Met+Cys, respectively. In the 34th wk, eggshell thickness decreased linearly at higher Met+Cys levels. In the 50th week, the optimal levels detected for eggshell thickness and percentage were 0.571 and 0.570% digestible Met+Cys, respectively. The percentages of proteins, branched-chain amino acids (leucine, isoleucine, and valine), histidine, and proline in eggs (albumen+yolk) showed a linear negative response in function of higher Met+Cys levels. Higher digestible Met+Cys levels (>0.630%) led to a good performance of layers, while lower Met+Cys levels improved the eggshell quality of layers in peak production. Optimal Met+Cys levels may change according to the price of the synthetic amino acid. |
| Databáze: | OpenAIRE |
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