Calcium supplementation in low nutrient density diet for meat ducks improves breast meat tenderness associated with myocyte apoptosis and proteolytic changes

Integrated metabolome and microbiome analysis reveals the effect of rumen-protected sulfur-containing amino acids on the meat quality of Tibetan sheep meat

Introduction

This study investigated the effects of rumen-protected sulfur-containing amino acids (RPSAA) on the rumen and jejunal microbiota as well as on the metabolites and meat quality of the longissimus lumborum (LL) in Tibetan sheep.

Methods

By combining 16S rDNA sequencing with UHPLC-Q-TOF MS and Pearson correlation analysis, the relationship between gastrointestinal microbiota, muscle metabolites and meat quality was identified.

Results

The results showed that feeding RPSAA can increase the carcass weight, abdominal fat thickness (AP-2 group), and back fat thickness (AP-2 and AP-3 group) of Tibetan sheep. The water holding capacity (WHC), texture, and shear force (SF) of LL in the two groups also increased although the fatty acids content and brightness (L*) value significantly decreased in the AP-2 group. Metabolomics and correlation analysis further showed that RPSAA could significantly influence the metabolites in purine metabolism, thereby affecting L* and SF. In addition, RPSAA was beneficial for the fermentation of the rumen and jejunum. In both groups, the abundance of Prevotella 1, Lachnospiraceae NK3A20 group, Prevotella UCG-003, Lachnospiraceae ND3007 group in the rumen as well as the abundance of Eubacterium nodatum group and Mogibacterium group in the jejunum increased. In contrast, that of Turicibacter pathogens in the jejunum was reduced. The above microorganisms could regulate meat quality by regulating the metabolites (inosine, hypoxanthine, linoleic acid, palmitic acid, etc.) in purine and fatty acids metabolism.

Discussion

Overall, reducing the levels of crude proteins in the diet and feeding RPSAA is likely to improve the carcass quality of Tibetan sheep, with the addition of RPMET (AP-2) yielding the best edible quality, possibly due to its ability to influence the gastrointestinal microbiota to subsequently regulate muscle metabolites.

Chromium propionate supplementation to energy- and protein-reduced diets reduces feed consumption but improves feed conversion ratio of yellow-feathered male broilers in the early period and improves meat quality

Growth performance and carcass traits may be retarded by low nutrient density diets. Organic chromium propionate (CrProp) can improve growth, carcass traits, and meat quality in farmed lambs, white broilers, and fish. Limited data regarding CrProp's impacts on yellow-feathered broilers are available. Eight hundred yellow-feathered male broilers (1-day old) were randomly allocated to 4 dietary groups and reared for 56 d. The trial was a 2 (dietary nutrient density) ×2 (CrProp) factorial arrangement with 4 diets: regular nutrient diet and low nutrient density (LND, reduction in metabolizable energy by 81 kcal and crude protein by 0.43%) diet supplemented with or without 200 mg/kg CrProp. Broilers were euthanized at d 56 after blood collection. The results indicated that the LND diet led to greater average daily feed intake (ADFI) from d 1 to 42 and feed conversion ratio (FCR) from d 22 to 42 (P < 0.05). Supplementation of CrProp improved body weight (BW) from d 1 to 56, average daily gain (ADG), and FCR during d 1 to 42 but reduced ADFI during d 1 to 21, as well as lowered abdominal fat percentage (P < 0.05). Supplementation with CrProp to regular and LND diets reduced ADFI but improved FCR from d 1 to 21 (P < 0.05). The LND diet lowered total antioxidant capacity (T-AOC) concentration and total superoxide dismutase (T-SOD) activity in the jejunal mucosa. CrProp elevated T-AOC levels and glutathione peroxidase activity (GSH-Px, P < 0.05). Dietary CrProp upregulated (P < 0.05) the expression of fatty acid transporter (FABP1) gene and peptide transporter (Pept1) gene. CrProp administration increased jejunal FABP1 expression and lowered cooking loss of breast meat (P < 0.05) in the LND group while reducing shear force (P = 0.009) of broilers treated by regular diet. In summary, CrProp administration to the LND diet can improve growth performance in the starter period and meat quality on d 56, possibly through upregulated nutrient transporter gene expression in the jejunum and enhanced antioxidant capability.

Dietary yucca extract and Clostridium butyricum promote growth performance of weaned rabbits by improving nutrient digestibility, intestinal development, and microbial composition

Yucca has abundant amounts of polyphenolics, steroidal saponins, and resveratrol and its extract can be used as a feed additive in the animal husbandry, which might contribute to the improvement in the growth and productivity in rabbit production. Hence, the current study aimed to examine the effects of yucca extract alone and in combination with Clostridium butyricum (C. butyricum) on growth performance, nutrient digestibility, muscle quality, and intestinal development of weaned rabbits. A total of 400 40-day-old male rabbits were randomly divided into 4 treatment groups for 40 days: (1) basal diet group, (2) basal diet contained 300 mg/kg of yucca extract, (3) basal diet supplemented with 0.4 × 10¹⁰ colony-forming units (CFU)/kg of C. butyricum, and (4) the blend of 0.4 × 10¹⁰/kg CFU of C. butyricum and 300 mg/kg of yucca extract. The supplementation of yucca extract or C. butyricum increased body weight (BW) of rabbits depending on the age, the combined addition of yucca extract and C. butyricum significantly increased BW, weight gain, and feed intake, companying with increased the digestibility of crud protein, fiber, phosphorous, and calcium as compared to control diet (P < 0.05). Furthermore, yucca extract and C. butyricum treatment alone and in combination notably increased the villus high and the ratio of villus high to crypt depth of rabbits (P < 0.05). The combined supplementation of yucca extract and C. butyricum altered the intestinal microbiota of rabbits, as demonstrated by increased the abundance of beneficial bacteria Ruminococcaceae and decreased the proportion of pathogenic bacteria such as Pseudomonadaceae and S24-7. In addition, the rabbits fed the diet with yucca extract and the blend of yucca extract and C. butyricum had significantly increased pH_45min, decreased pressing loss, drip loss, and shears force when compared with rabbits received control diet (P < 0.05). Diet with C. butyricum or its mixture with yucca extract increased the fat content of meat, while the combined addition of yucca extract and C. butyricum declined the content of fiber in meat (P < 0.05). Collectively, the combined use of yucca extract and C. butyricum showed better results on growth performance and meat quality, which might be closely associated with the improved intestinal development and cecal microflora of the rabbits.