Effect of season on slaughter performance, meat quality, muscle amino acid and fatty acid composition, and metabolism of pheasants (Phasianus colchicus)

SNPS within the SLC27A6 gene are highly associated with Hu sheep fatty acid content

Fatty acids (FA) are an important factor affecting meat quality and human health, and the important role of the solute carrier family 27 member 6 (SLC27A6) in FA metabolism has been demonstrated in several species. However, the expression profile of the SLC27A6 in different tissues and the effect of its polymorphism on FA in sheep are currently unknown. This study aimed to explore the differences in FAs in the longissimus dorsi (LD) of 1,085 Hu sheep, the expression profile of SLC27A6, and confirm the effect of single nucleotide polymorphisms (SNPs) on FA phenotypes. We found that many FA phenotypes differ significantly across different seasons, and winter promoted the deposition of polyunsaturated fatty acids (PUFA). The mRNA expression level of SLC27A6 in the lung was significantly higher than that in the heart, testis, and LD. A total of 16 SNPs were detected in the SLC27A6, and 14 SNPs were successfully genotyped by improved multiplex ligase detection reaction (iMLDR) technology. Correlation analysis showed that 7 SNPs significantly affected at least one FA phenotype. Among them, SNP14 contributes to the selection of lamb with low saturated fatty acid content and high PUFA content. Combined genotypes also significantly affected a variety of beneficial FAs such as C18:3n3, C20:4n6, C22:6n3, and monounsaturated fatty acids. This study suggests that SLC27A6 plays an important role in FA metabolism and SNPs that are significantly associated with FA phenotype could be used as potential molecular markers for later targeted regulation of FA profiles in sheep.

Effects of fulvic acid on broiler performance, blood biochemistry, and intestinal microflora

To study the effects of mineral fulvic acid (FuA) on broiler performance, slaughter performance, blood biochemistry index, antioxidant function, immune performance, and intestinal microflora, 360 Arbor Acres (AA) broiler chickens with similar body weights were randomly divided into 5 groups with 6 replicates in each group and 12 chickens in each replicate in the current study. Chickens in the control group (C) were fed with the basal diet, and chickens in the test groups (I, II, III, and IV) were fed with the diet supplemented with 0.05%, 0.1%, 0.2%, and 0.3% mineral FuA, respectively. The indicators were measured on the hatching day, d 21 and d 35. From the whole experimental period, FuA supplement significantly increased average body weight (ABW) (P < 0.05), average daily gain (ADG) of broilers (P < 0.05), and thymus weight (P < 0.05) in II and IV groups, but bascially reduced the pH value of thigh meat. FuA supplement significantly improved aspartate aminotransferase (AST) activity in the group III on d 35 (P < 0.05) and the serum levels of IgA and IgG on d 21 and d 35 (P < 0.05), but reduced glutathione peroxidase (GSH-Px) level on d 21 (P < 0.05) and malondialdehyde (MDA) level in serum on d 35 (P < 0.05). FuA supplement significantly affected the abundance of Barnesiella, Lachnospiraceae, Alistipes, Lactobacillus, and Christensenellaceae on genus level. Differences between group III and other groups were significant in the genera microflora composition on d 21 and d 35. Functional analysis showed that the cecum microbiota were mainly enriched in carbohydrate metabolism, amino acid metabolism, and energy metabolism. In conclusion, FuA may potentially have significant positive effects on the growth performance and immune function of AA chickens through the modulation of the gut microbiota, and the 0.1% FuA was the best in broiler diet based on the present study.

Dietary novel alkaline protease from Bacillus licheniformis improves broiler meat nutritional value and modulates intestinal microbiota and metabolites

BACKGROUND

Different types of exogenous protease supplements have a positive impact on animal performance, but their effects on the nutritional value of meat and the gut microbial community of broilers have not been extensively studied. The objective of this investigation was to determine the impact of supplementation with a novel alkaline protease derived from Bacillus licheniformis (at doses of 0, 100, 200, 300, and 400 g/t) on the fatty acid and amino acid profiles, inosine monophosphate (IMP) levels, total volatile basic nitrogen (TVB-N) content found within the breast muscle, as well as the impact on the cecal microbiota and metabolites.

RESULTS

Supplementation with 200-400 g/t of the novel protease resulted in a significant elevation in the concentration of essential amino acids (P < 0.001), flavor amino acids (P < 0.001), and total protein (P = 0.013) within the breast muscle. Results derived from the 16S rRNA sequencing and untargeted metabolomics analysis of the cecal content revealed that the novel protease reshaped the cecal microbial and metabolite profiles. In particular, it led to increased relative abundances of Bacteroides, Lactobacillus, Alistipes, and Eubacterium, while simultaneously causing a reduction in the metabolites of D-lactic acid and malonic acid. Moreover, correlation analyses unveiled significant relationships between distinct microbes and metabolites with the contents of IMP, fatty acids, and amino acids in the broiler's breast muscle.

CONCLUSION

In summary, the novel protease regulated the intestinal microbial community and metabolism, thereby inducing changes in the compositions of fatty acids and amino acids profiles, as well as IMP levels in broiler meat. These alterations significantly contributed to the enhancement of the nutritional value and flavor of the meat.

Seasonal adaptation of Mangalica pigs in terms of muscle morphology and metabolism

The skeletal muscle plays an important role in maintaining body temperature, which is mediated by thermogenesis and glucose or lipid metabolism. Mangalica is a native Hungarian pig that has cold tolerance and can live in grazing environments throughout the year. We evaluated the morphological and genetic aspects of Mangalica using muscle tissues to elucidate the mechanisms underlying the tolerance to seasonal effects in grazing environments. The muscle tissues in each season were analysed using morphological evaluation and electron microscopy. The cross-sectional area of skeletal muscle cells in summer was significantly larger than that in winter. The thickness of myofibrils in summer was significantly higher than in winter. The thickness of the Z-line in winter was significantly higher than in summer. The expression of MYH4 and GLUT4 was significantly lower in winter than in summer. The result of ATPase staining indicated significantly increase the muscle fibre ratio of type 1 in winter than that in summer. These findings indicate that the muscle fibre in Mangalica shifts from fast-twitch to slow-twitch fibre, and the metabolic physiology of the muscle was adapted to the cold environment. This study demonstrates that Mangalica gained tolerance to both seasonal heat and cold stresses that are caused by significant changes in ambient temperature in a year because of changes in their muscle fibre type and metabolic function. This study may contribute to elucidating the mechanism of thermogenetic adaptation in cold and heat environments among mammals.

Effects of fermented herbal tea residue on meat quality, rumen fermentation parameters and microbes of black goats

Herbal tea residue (HTR) is generally considered to be a reusable resource which has still retains considerable proportion of nutrients and active substances. This study aimed to investigate the effects of substitution of whole corn silage with fermented herbal tea residue (FHTR) on meat quality, serum indices, rumen fermentation, and microbes in Chuanzhong black goats. Twenty-two female Chuanzhong black goats (4 months old) with similar weight (9.55 ± 0.95 kg) were selected and randomly divided into two groups. FHTR was used to replace 0% (CON group) and 30% (FHTR group) of whole corn silage in the diets and fed as a total mixed ration (TMR) for Chuanzhong black goats. The adaptation feeding period was 7 days, and the experimental period was 35 days. Results illustrated that the FHTR group had higher value of a* and concentrations of DM and CP and lower rate of water loss (P < 0.05) than the CON group. For the serum indices, goats fed with 30% FHTR had higher (P < 0.05) concentration of CR on day 35. For rumen fermentation, the pH and ratio of acetic acid/propionic acid (AA/PA) in the FHTR group were significantly lower than those in the CON group (P < 0.05). In addition, we studied the goats's rumen microbial community composition and found that the dominant phyla were Firmicutes, Bacteroidetes,and Tenericutes; and the dominant genera were Quinella, Candidatus_Saccharimonas, and Saccharofermentans. There was a significant difference in the beta diversity of the rumen microbiota between groups (P < 0.05). To sum up, the addition of FHTR can affect the meat quality, serum indices, improved rumen fermentation by adjusted the diversity and function of the rumen microbiota.