title: Effects of dietary leucine supplementation in low crude protein diets on performance, nitrogen balance, whole-body protein turnover, carcass characteristics and meat quality of finishing pigs.
abstract: Eighteen Duroc × Landrace × Yorkshire barrows, with an average initial body weight (BW) of 75.4 ± 2.0 kg, were randomly allotted to one of three diets with six replicates per treatment for 25 days. The diets comprised a normal protein diet (NP, 14.5% crude protein), a low crude protein diet supplemented with 0.27% alanine (LP + Ala, 10.0% crude protein), or a low crude protein diet supplemented with 0.40% leucine (LP + Leu, 10.0% crude protein). The whole-body protein synthesis rate, whole-body protein breakdown rate and protein deposition rate in pigs fed the LP + Leu diet were similar to the NP diet (P > 0.05), and both were significantly higher than pigs fed the LP + Ala diet (P < 0.05). The Longissimus muscle area (LMA) of pigs fed the LP + Leu diet was larger than those fed the LP + Ala diet (P = 0.05). In addition, drip loss and intramuscular fat of pigs fed the LP + Ala diet were higher than that of the others (P < 0.05). In conclusion, supplementation of leucine in low protein diet could stimulate protein deposition and improve the meat quality of finishing pigs more than an alanine-supplemented one.
authors.affiliation: State Key Laboratory of Animal Nutrition, Ministry of Agriculture Feed Industry Centre, Beijing.
authors.forename: Shihai
authors.initials: S
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Animal Nutrition, Ministry of Agriculture Feed Industry Centre, Beijing.
authors.forename: Licui
authors.initials: L
authors.lastname: Chu
authors.affiliation: State Key Laboratory of Animal Nutrition, Ministry of Agriculture Feed Industry Centre, Beijing.
authors.forename: Shiyan
authors.initials: S
authors.lastname: Qiao
authors.affiliation: Animal Nutrition Institute, Sichuan Agricultural University, Key Laboratory of Animal Disease-Resistance Nutrition, Ministry of Education, Ya'an, Sichuan, China.
authors.forename: Xiangbing
authors.initials: X
authors.lastname: Mao
authors.affiliation: State Key Laboratory of Animal Nutrition, Ministry of Agriculture Feed Industry Centre, Beijing.
authors.forename: Xiangfang
authors.initials: X
authors.lastname: Zeng
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism; D000821:Animal Feed; D000824:Animal Nutritional Physiological Phenomena / Q000502:physiology*; D000818:Animals; D004032:Diet / Q000662:veterinary*; D004044:Dietary Proteins / Q000008:administration & dosage*; D019587:Dietary Supplements; D063427:Food Quality; D007930:Leucine / Q000008:administration & dosage*; D008297:Male; D008460:Meat / Q000032:analysis; D018482:Muscle, Skeletal / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism*; D013552:Swine / Q000254:growth & development* / Q000378:metabolism*
chemical_list: D004044:Dietary Proteins; D011506:Proteins; D007930:Leucine; D009584:Nitrogen
keywords: carcass characteristics; finishing pig; low crude protein diet; meat quality; protein turnover