Subject(s)
Altitude , Transients and Migrants , Humans , Electron Transport , Leukocytes, MononuclearABSTRACT
This study investigated the effects of ramie (0, 3, 6, 9, or 12%) included in finishing diets on carcass traits and meat quality of Xiangcun black pigs. Results showed that ramie decreased (linear, Pâ¯<â¯.05) backfat depth while it increased (linear, Pâ¯<â¯.05) loin-eye area. A quadratic effect of shear force in longissimus thoracis (LT) was observed, and the lowest value was noted in the 6% ramie group. Protein content in LT was linearly increased by ramie (linear, Pâ¯<â¯.01). Meanwhile, dietary ramie linearly decreased lipogenic genes mRNA levels and fiber cross-sectional area, but it linearly increased total fiber number of LT. These results suggest that ramie included in the diet <9% is an effective feed crop to partly improve carcass trait and muscle chemical composition without negatively affecting growth performance, and the underlying mechanism may be due to the changed lipogenic potential and myofiber characteristics induced by ramie.
Subject(s)
Adipose Tissue, White/chemistry , Animal Feed , Boehmeria/chemistry , Dietary Fats/analysis , Food Quality , Meat/analysis , Muscle, Skeletal/metabolism , Adipose Tissue, White/growth & development , Animal Nutritional Physiological Phenomena , Animals , Animals, Inbred Strains , China , Dietary Proteins/analysis , Gene Expression Regulation, Developmental , Humans , Muscle Proteins/analysis , Muscle Proteins/genetics , Muscle Proteins/metabolism , Muscle, Skeletal/growth & development , Nutritive Value , Plant Leaves/chemistry , Plant Shoots/chemistry , Random Allocation , Shear Strength , Sus scrofa , Weight GainABSTRACT
Leucine (Leu) and its metabolites α-ketoisocaproate (KIC) and ß-hydroxy-ß-methyl butyrate (HMB) are potent regulators of protein turnover. The aim of this study was to compare the inhibitory effects of Leu, KIC, and HMB on protein degradation and to investigate the mechanisms involved. The results showed that the inhibitory effect of HMB (0.38 ± 0.04) was more potent than that of Leu (0.76 ± 0.04) and KIC (0.56 ± 0.04, P < 0.01), and was significantly abolished in the presence of LY294002 (1.48 ± 0.02) and rapamycin (1.96 ± 0.02, P < 0.01). In the presence of insulin, the inhibitory effect of HMB (0.34 ± 0.03) was still more effective than that of Leu (0.60 ± 0.04) and KIC (0.57 ± 0.08, P < 0.05). Interestingly, LY294002 treatment markedly attenuated the effect of HMB, while rapamycin treatment failed to exert the same effect. Thus, HMB appears to be more potent than Leu and KIC in inhibiting protein degradation in the absence or presence of insulin, and this inhibitory effect may be dependent on PI3K/Akt signaling pathway regardless of insulin, and mTOR signaling was only involved in this effect of HMB in the absence of insulin.
Subject(s)
Leucine/pharmacology , Muscle Fibers, Skeletal/drug effects , Proteolysis/drug effects , Valerates/pharmacology , Animals , Cell Line , Insulin/pharmacology , Keto Acids/pharmacology , Mice , Muscle Fibers, Skeletal/metabolism , Muscle Proteins/genetics , Muscle Proteins/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , SKP Cullin F-Box Protein Ligases/genetics , SKP Cullin F-Box Protein Ligases/metabolism , TOR Serine-Threonine Kinases/metabolism , Tripartite Motif Proteins/metabolism , Ubiquitin-Protein Ligases/metabolismABSTRACT
A 60-days feeding trial was conducted to determine the effect of dietary supplementation of Lonicera macranthoides leaf (LML) on growth performance, meat quality, and free amino acid profiles in growing-finishing pigs. L. macranthoides leaves were harvested, air-dried and milled to powder. A total of 288 crossbred barrows (Large White × Landrace) with an average initial BW of 54.0 ± 3.4 kg were randomly allocated to 3 treatment groups and fed either a basal diet or a diet supplemented with 0.5% or 1.0% LML powder. Results showed that diet supplemented with LML powder did not affect average daily feed intake (ADFI) and feed: gain ratio (P > 0.05) in growing-finishing pigs. Moreover, diet supplemented with LML powder showed no significant effects on carcass traits (P > 0.05) including dressing percentage, backfat thickness and loin muscle area, and meat quality traits (P > 0.05) including meat color, intramuscular fat and cooking loss. However, diet supplemented with LML powder significantly improved free amino acid profiles in serum and longissimus thoracis muscle in growing-finishing pigs. Most importantly, dietary LML powder increased total free amino acids content (P < 0.001) and essential free amino acid content (P < 0.001) in longissimus thoracis muscle. These results indicate that LML has the potential to improve the nutritional value of meat through improving free amino acid profiles.
