The study aimed to evaluate the influences of the dietary supplementation of Chinese yam polysaccharide (CYP) on the carcass performance, antioxidant capacity, and meat quality of broilers. Three hundred and sixty healthy 1-day-old broilers with similar body weight (39 ± 1 g, gender balanced) were randomly divided into four groups (control, CYP1, CYP2, and CYP3 groups). In the control group, broilers were fed a basal diet with CYP, and the CYP1, CYP2, and CYP3 groups were fed diets supplemented with 250, 500, and 1000 mg/kg CYP, respectively. There were three replicates in each group, 30 birds in each replicate, and the feeding trial lasted for 48 days. Statistical analysis was performed using SPSS 17.0 (SPSS Inc., Chicago, IL, USA) by one-way analysis of variance. The results showed that compared with the control group, dietary supplementation with 500 mg/kg CYP can improve live weight, half-eviscerated carcass percentage, eviscerated carcass percentage, and thigh muscle percentage. Moreover, dietary supplementation with 500 mg/kg CYP can improve the contents of total antioxidant capacity (T-AOC), total superoxide dismutase (T-SOD), glutathione peroxidase (GPX), and glutathione s-transferase (GST) in serum (p < 0.05). Meanwhile, the mRNA expression levels of nuclear factor-erythroid 2-related factor 2 (Nrf2), heme oxygenase 1 (HO-1), quinone oxidoreductase (NQO1), superoxide dismutase 1 (SOD1), glutathione peroxidase 1 (GPX1), and catalase (CAT) in the liver; the mRNA expression levels of HO-1, NQO1, GPX1, and CAT in the breast muscle; and the mRNA expression levels of NQO1, SOD1, and CAT in the thigh muscle of broilers in the CYP2 group were significantly increased (p < 0.05). In addition, the yellowness and shear force of the thigh and breast muscles and the content of malondialdehyde (MDA) in the serum of broilers in the control group were higher than that in the CYP2 groups (p < 0.05). The results demonstrated that the CYP2 group had the best effect on improving meat quality. In conclusion, dietary supplementation with 500 mg/kg CYP can improve the meat quality of broilers by improving carcass quality, meat color, shear force, and antioxidant capacity.

The purpose of this study is to evaluate the influences of Chinese yam polysaccharide (CYP) dietary supplementation on the composition of intramuscular fat (IMF) and fatty acids (FA) in thigh and breast muscles of broilers. Three hundred and sixty healthy one-day-old broilers (the breed of Crossbred chicken is named 817) with gender-balanced and similar body weight (39 ± 1 g) were randomly allocated into four groups (control, CYP1, CYP2, and CYP3 groups). Broilers in the control group were only fed a basal diet, and broilers in CYP1 group were fed the same diets further supplemented with 250 mg/kg CYP, the CYP2 group was fed the same diets further supplemented with 500 mg/kg CYP, and the CYP3 group was fed the same diets further supplemented with 1000 mg/kg CYP, respectively. Each group consisted of three replicates and each replicate consisted of 30 birds. The feeding days were 48 days. The results observed that the CYP2 group (500 mg/kg) can up-regulate the mRNA expression levels of β-catenin in thigh muscle compared to the control group. At the same time, all CYP groups (CYP1, CYP2, and CYP3 groups) can up-regulate mRNA expression of Wnt1 and β-catenin in breast muscle, while mRNA expression of PPARγ and C/EBPα in breast and thigh muscles could be down-regulated (p < 0.05). In summary, 500 mg/kg of CYP dietary supplementation can reduce IMF content and improve the FAs composition, enhancing the nutritional value of chicken meat.

This experiment was conducted to evaluate the effects of dietary Chinese yam polysaccharides (CYP) on myogenic differentiation 1 (MYOD1), myogenin (MYOG), and myostatin (MSTN) mRNA expression of breast and thigh muscle tissues in broilers. A total of 360 (1-day-old, gender-balanced) crossbred broilers chicks with similar body weight (BW) were randomly distributed into four groups, with three replicates in each group and each replicate included 30 broilers. The feeding trial lasted for 48 days. Experimental broilers were fed 0.00 mg/kg basal diet (control group), 250 mg/kg, 500 mg/kg, and 1000 mg/kg CYP, respectively. The results showed that CYP250 and CYP500 groups had higher thigh muscle percentage (TMP) compared to the control group (p < 0.05). Meanwhile, the expression of MYOD1, MYOG mRNA in breast muscle tissues of CYP500 and CYP1000 groups was higher (p < 0.05), and the expression of MSTN mRNA in thigh muscle of CYP250, CYP500, and CYP1000 groups was lower than that of the control group (p < 0.05). In addition, there was no significant difference in the expression of MYOD1 mRNA in the thigh muscle tissue of each group (p > 0.05). Bivariate correlation analysis showed that the expression levels of MYOD1, MYOG, and MSTN mRNA in the thigh muscle tissue of broiler chickens in the CYP500 group were positively correlated with TMP. However, the expression of MYOG mRNA in thigh muscle tissue of the CYP1000 group was negatively correlated with TMP. In general, this study indicated that appropriate dietary CYP supplementation influenced the growth and development of thigh muscle tissue in broilers by altering TMP and muscle tissue development-related genes expression. Therefore, CYP could be used as a potential feed additive to promote the development of muscle tissues in broilers.

Coat color is a crucial production trait for fur-bearing animals and significantly influences their economic value. The remarkable diversity of coat colors in rex rabbits not only provides a wide range of market options but also serves as an essential resource for investigating the genetic mechanisms underlying coat color formation. In this study, we conducted integrated transcriptomic and proteomic profiling of skin tissues from black and white Rex Rabbits, revealing the presence of 52 co-expressed genes/proteins. Proteomic analysis revealed a significant upregulation of PMEL (p = 0.030, FC = 2.194), while transcriptomic data indicated an even more pronounced upregulation (p = 0.028, FC = 35.279). Therefore, PMEL (Premelanosome Protein) may serve as a pivotal regulator of melanogenesis in Rex Rabbits. Our findings indicate that PMEL overexpression in melanocytes increases melanin content, promotes melanocyte proliferation, and enhances the expression of melanin-related genes (MITF, TYR, TYRP1, and GPNMB) while inhibiting melanocyte apoptosis. Conversely, PMEL knockdown significantly reduces melanin content, melanocyte proliferation, and the expression of melanin-related genes while promoting melanocyte apoptosis. These findings suggest that PMEL contributes to melanogenesis in Rex Rabbits.

The rumen microbiome plays an important role in converting dietary carbohydrates into metabolites associated with host physiology, yet the relationships between microbial carbohydrate metabolism and host lipid metabolism remain incompletely understood. Here, we compared Japanese Wagyu and Nanyang cattle to investigate microbiota–metabolite–host associations in relation to breed-associated differences in intramuscular fat (IMF) deposition. Metagenomic analysis revealed differences in rumen microbial community composition and functional profiles between breeds, including differential abundances of carbohydrate-active enzyme (CAZyme) families associated with polysaccharide degradation. Wagyu cattle exhibited higher abundances of glycoside hydrolase (GH) families GH5 (cellulose degradation) and GH92 (alpha-mannan degradation), whereas GH13 (starch degradation) and GH43 (arabinoxylan and arabinan degradation) were enriched in Nanyang cattle, together with differences in carbohydrate-degrading genera, including Prevotella , Fibrobacter , and Butyrivibrio . These microbial functional differences were accompanied by distinct fermentation profiles, with higher ruminal acetate and butyrate concentrations in Wagyu cattle and higher propionate concentrations in Nanyang cattle. Proteomic analysis of the longissimus dorsi muscle identified breed-associated differences in proteins involved in lipid synthesis, lipid storage, and energy metabolism, including FABP4, FASN, PLIN1, ACSS2, and IDH1, which showed higher abundances in Wagyu cattle. Correlation analyses identified associations among microbial taxa, CAZyme families, fermentation metabolites, and host proteins related to lipid metabolism and IMF deposition. Overall, these findings reveal coordinated breed-associated differences in rumen microbial functions, fermentation characteristics, and host lipid metabolic profiles, providing insights into microbiota–host metabolic associations related to IMF deposition in cattle. Keypoints: • Rumen carbohydrate-active enzyme (CAZyme) profiles differ between Wagyu and Nanyang cattle. • Wagyu cattle show higher acetate and butyrate levels. • Microbiota–volatile fatty acids (VFAs)–proteome axis is linked to intramuscular fat (IMF) deposition