Effects of lysine/ideal protein level on performance, carcass characteristics, digestibility and blood parameters of Duroc barrows from 30 to 50kg

• Autor(a) principal: Palhares, L. O.
• Data de Publicação: 2020
• Outros Autores: Dutra Junior, W. M., Lourenco-Silva, M. [UNESP], Carmo, M. R., Serafim, J. E., Gasparini, S. P., Lima, T. S., Holanda, M. C. R.
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1590/1678-4162-11240; http://hdl.handle.net/11449/208789
• topic: amino acid; ideal protein; growth phase; nutritional requirements

The objective of this study was to evaluate digestible lysine levels, keeping the relation among amino acids for Duroc barrows from 30 to 50kg. Fifty Duroc barrows (30.35 +/- 1.96kg live weight) were allotted in a completely randomized experimental design, divided in five treatments with five replicates and two animals in each experimental unit. The treatments consisted of digestible lysine levels (0.73%; 0.83%; 0.93%; 1.03% and 1.13%), keeping the relation with other essential amino acids. Performance, carcass characteristics, blood parameters and digestibility of the diets were evaluated. There was a quadratic response on weight gain, feed conversion and creatinine serum concentration as a function of the digestible lysine levels, with the greater levels obtained at 0.92%, 0.93% and 0.93%, respectively. The carcass characteristics were not influenced by the treatments. There was a linear increase of apparent digestibility of crude protein, total serum protein and urea. Results suggest that the requirement of protein and digestible lysine was 16.70% and 0.93%, respectively, providing improvements on weight gain, feed conversion and creatinine serum concentration of Duroc barrows in the growth phase.