1. The experiment was conducted in order to determine the effect of the direction of turkey crossing on quality traits of their thigh muscle.
2. In total, 1358 turkeys of slow- (SG) and fast-growing (FG) lines as well as SF crosses (SG × FG) and FS crosses (FG × SG) were reared with access to free range to 21 weeks of age in the case of males and 15 weeks of age in the case of hens.
3. After slaughter of 15 males and 15 hens from each genetic line, their thigh muscles were examined and the following traits were measured after 5-min, 45-min, 2-h and 24-h post-mortem: temperature, pH, glycogen content (G), lactate content (L) and electrical conductivity (EC). Quality attributes were evaluated based on chemical composition, water holding capacity, cooking loss (%) and colour.
4. The rate of post-mortem changes in temperature, G, L and pH in muscles differed among the 4 lines of turkeys, with the highest metabolic rate determined for muscles of SG turkeys, followed by muscles of SF, FS and FG birds. A more beneficial muscle water holding capacity of both sexes of turkeys and better results of cooking loss in male muscles were found in SG and SF turkeys. The thigh muscles of the crosses were characterised by a higher content of protein and a lower content of fat compared to the muscles of FG turkeys, and in the case of the males also by a higher protein content compared to the muscles of SG birds.
5. Owing to the faster post-mortem metabolism, better water holding capacity, lower cooking loss and fat content at a similar content of protein, the thigh muscles of SF crosses raised in the free range system represent a better quality of meat for consumers compared to the thigh muscles of FS turkeys. 相似文献
Liver metabolism is affected by nutrients. The aim of this study was to explore the effects of low‐protein diets (17% crude protein, CP) supplemented with branched‐chain amino acids (BCAAs), including leucine (Leu), isoleucine (Ile) and valine (Val), on hepatic amino acid profile and lipid metabolism in growing pigs. The ratio of Leu : Ile : Val in all groups was 1 : 0.51 : 0.63 (20% crude protein, CP), 1 : 1 : 1 (17% CP), 1 : 0.75 : 0.75 (17% CP), 1 : 0.51 : 0.63 (17% CP) and 1 : 0.25 : 0.25 (17% CP) respectively. Results revealed that compared to the positive control group (1 : 0.51 : 0.63, 20% CP), the low‐protein diets significantly augmented the concentrations of most essential amino acids and non‐essential amino acids (p <.05), with the greatest values observed in the 1 : 0.25 : 0.25 group. Moreover, relative to the control, the low‐protein diets with the Leu : Ile : Val ratio ranging from 1 : 0.75 : 0.75 to 1 : 0.25 : 0.25 markedly downregulated the mRNA abundance of acetyl‐CoA carboxylase (ACC), lipoprotein lipase (LPL) and fatty acid‐binding protein 4 (FABP‐4) (p <.05), and upregulated the mRNA expression of hormone‐sensitive lipase (HSL), peroxisome proliferator‐activated receptor‐g coactivator‐1α (PGC‐1α), uncoupling protein 3 (UCP3) and liver carnitine palmitoyltransferase 1 (L‐CPT‐1) (p <.05). Therefore, our data suggest that protein‐restricted diets supplemented with optimal BCAA ratio, that is, 1 : 0.75 : 0.75–1 : 0.25 : 0.25, induce a shift from fatty acid synthesis to fatty acid oxidation in the liver of growing pigs. These effects may be associated with increased mitochondrial biogenesis. 相似文献
We investigated effects of Rendement Napole (RN ) genotype on metabolic markers in Ossabaw pigs fed diets with different levels of dietary fat. Thirty‐two pigs, belonging to either the wild‐type (WT , rn+/rn+) or carrier (CAR , RN ?/rn+) genotypes (n = 16/genotype), were divided into two dietary groups, (high fat [HF ] or low fat [LF ]) diets, for 12 weeks (n = 8 pigs/genotype/diet) after which pigs were killed for gene expression analysis by RT ‐PCR . Feeding HF diet caused increased daily gain (ADG , p <.05) and final body weight (BW ) (p <.05) in comparison with the LF diet (p <.05). Feed efficiency (gain:feed) was higher (p <.05) in pigs on the HF and was higher (p <.05) in CAR pigs compared to WT . There was genotype × diet interaction (p =.05) on final BW such that CAR animals on LF diet had the same final BW as animals of both genotypes on HF diet. Carrier pigs on LF diet had higher (p <.05) average daily gain and gain:feed than WT pigs. There was a trend (p <.08) for a higher feed consumption in pigs on the LF diet. Backfat thickness was higher (p <.01) in pigs on the HF diet. Serum triglyceride was higher (0.62 vs. 0.33 mg/dl, p <.01) in pigs on HF diet. Serum insulin was higher (p <.05) in CAR versus WT pigs (0.40 vs. 0.015 μg/ml). Pigs on the HF diet had a higher (p <.05) serum insulin compared to those on the LF diet (0.032 vs. 0.023 μg/ml). Carnitine palmitoyl transferase 1‐alpha was higher (p <.05) in the longissimus dorsi and semitendinosus muscles of pigs on HF diet. Acyl‐CoA oxidase I was elevated (p <.05) in the liver of pigs on HF diet. Fatty acid synthase was lower in the longissimus dorsi muscle, liver and mesenteric fat (p <.05) of carrier pigs. The RN gene regulates specific metabolic markers in the Ossabaw pigs. 相似文献