title: Effect of dietary lysine on performance and expression of electron transport chain genes in the pectoralis major muscle of broilers.
abstract: 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.
authors.affiliation: 1Department of Animal Science,Universidade Federal de Sergipe,49100-000 São Cristóvão,SE,Brazil.
authors.forename: C O
authors.initials: CO
authors.lastname: Brito
authors.affiliation: 1Department of Animal Science,Universidade Federal de Sergipe,49100-000 São Cristóvão,SE,Brazil.
authors.forename: J L L
authors.initials: JLL
authors.lastname: Dutra
authors.affiliation: 1Department of Animal Science,Universidade Federal de Sergipe,49100-000 São Cristóvão,SE,Brazil.
authors.forename: T N
authors.initials: TN
authors.lastname: Dias
authors.affiliation: 1Department of Animal Science,Universidade Federal de Sergipe,49100-000 São Cristóvão,SE,Brazil.
authors.forename: L T
authors.initials: LT
authors.lastname: Barbosa
authors.affiliation: 1Department of Animal Science,Universidade Federal de Sergipe,49100-000 São Cristóvão,SE,Brazil.
authors.forename: C S
authors.initials: CS
authors.lastname: Nascimento
authors.affiliation: 2Department of Animal Science,Universidade Federal Rural de Pernambuco,52171-900 Recife,PE,Brazil.
authors.forename: A P G
authors.initials: APG
authors.lastname: Pinto
authors.affiliation: 3Department of Animal Science,Universidade Federal de Viçosa,36570-900 Viçosa,MG,Brazil.
authors.forename: L F T
authors.initials: LFT
authors.lastname: Albino
authors.affiliation: 4Department of Physiology,Universidade Federal de Sergipe,49100-000 São Cristóvão,SE,Brazil.
authors.forename: R P M
authors.initials: RPM
authors.lastname: Fernandes
authors.affiliation: 1Department of Animal Science,Universidade Federal de Sergipe,49100-000 São Cristóvão,SE,Brazil.
authors.forename: M S
authors.initials: MS
authors.lastname: Macário
authors.affiliation: 1Department of Animal Science,Universidade Federal de Sergipe,49100-000 São Cristóvão,SE,Brazil.
authors.forename: J S
authors.initials: JS
authors.lastname: Melo
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D030161:Avian Proteins / Q000235:genetics* / Q000378:metabolism; D002645:Chickens / Q000254:growth & development* / Q000378:metabolism; D004032:Diet / Q000662:veterinary; D004063:Digestion; D008239:Lysine / Q000378:metabolism*; D008297:Male; D010369:Pectoralis Muscles / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011897:Random Allocation
chemical_list: D030161:Avian Proteins; D012333:RNA, Messenger; D008239:Lysine
keywords: amino acids; genes; protein deposition; respiratory chain