The objective of this study was to investigate the rumen degradation characteristics of grain amaranth hay (Amaranthus hypochondriacus) at four different growth stages. The aim of this study was to evaluate the nutritional value of grain amaranth hay at different growth stages by chemical composition, in vivo digestibility, and in situ degradability. Three Boer goats with permanent ruminal fistulas were selected in this study. Amaranthus hay at four different growth stages (squaring stage (SS), initial bloom stage (IS), full-bloom stage (FS) and mature stage (MS)) was crushed and placed into nylon bags. Each sample was set up with three replicates, and two parallel samples were set up in fistulas at each time point. The rumen degradation rates of dry matter (DM), crude protein (CP), neutral detergent fibre (NDF) and acid detergent fibre (ADF) were determined at 0, 6, 12, 24, 36, 48 and 72 h. The results were as follows: (1) The concentration of CP in SS was the highest and was significantly higher than that in other stages (p < 0.05), whereas the contents of NDF and ADF gradually increased with the extension of the growing period and reached a maximum in MS; (2)The degradation of CP in the rumen at 72 h of SS and IS was more than 80%. Compared with other stages, the effective degradability of CP was highest in SS (p < 0.05) and reached 87.05% at 72 h, and the degradation rate was the lowest in MS; and (3) The effective degradability of NDF in IS was the highest (p < 0.05) and reached 69.326% at 72 h. The effective degradability of ADF in MS was the highest (p < 0.05) and reached 65.728% at 72 h. The effective degradability of DM and CP in SS was the highest. In conclusion, among the four stages, IS was superior in chemical composition and rumen degradability characteristics.

This study aimed to conduct precise supplementation for pregnant cashmere goats under grazing based on the feeding standard. Eight Inner Mongolian pregnant cashmere goats of near-average body weight were selected at early gestation (44.41 ± 4.03 kg) and late gestation (46.54 ± 4.02 kg) to measure their nutrient intake. Then, two pregnant cashmere goat flocks, No. 10 (control group, on-farm supplement) and No. 11 (supplemented group, supplement based on standard), with the same goat herd structure and grassland type, were chosen to conduct the supplemental feeding experiment. The results showed that pregnant cashmere goats lacked daily the intake of dry matter, digestive energy, crude protein and most essential mineral elements under grazing. After supplemental feeding, the supplementation based on the feeding standard increased the cashmere length and cashmere length growth volume and decreased the cashmere fineness, with no statistical significance. The goat cashmere yield, goat weight after shearing, single and twin-birth kid weight and kids’ mature secondary hair follicle density were significantly higher in the supplemented group (p < 0.05). In conclusion, supplementation in accordance with “Nutrient Requirements of Cashmere Goats” can enhance pregnant cashmere goats’ fiber production, growth performance, fertility and kids’ secondary hair follicles development, which is of great importance for the healthy and precise nutrition and management of cashmere goats.

This study was conducted to investigate the rumen degradability and intestinal digestibility of mutton sheep diets different in concentrate-to-forage ratio, NFC/NDF, and ingredient combination, providing a guideline for the selection of a fattening diet for mutton sheep. Twenty-eight diets composed of four raw material combinations and seven concentrate-to-forage ratios and four three-year-old mutton sheep with permanent rumen fistulas were used in the experiments. The nutrient composition of the diets was first analyzed, and then an in situ method and in vitro three-step method were separately used to measure the rumen degradability and intestinal digestibility, mainly focusing on the effects of dietary concentrate-to-forage ratio and NFC/NDF as well as the effects of soybean meal and soybean meal replacement and peanut vine and peanut vine replacement. The results showed that a dietary concentrate-to-forage ratio of 70:30~80:20 and an NFC/NDF ratio of 1.5~2.0 are recommended for fattening mutton sheep, and low-cost cottonseed meal and rapeseed meal can be feasible alternative protein sources to soybean meal. In addition, the nutritional values of sunflower seed hulls and rice hulls for mutton sheep are lower than that of peanut vine. Such a study can provide practical guidelines for enterprises and farmers, being of important significance for the high-quality development of the mutton sheep industry.

Hair follicles, unique skin appendages, undergo cyclic phases (anagen, catagen, telogen) governed by melatonin and associated molecular pathways. Melatonin, synthesized in the pineal gland, skin, and gut, orchestrates these cycles through antioxidant activity and signaling cascades (e.g., Wnt, BMP). This review examines melatonin’s biosynthesis across tissues, its regulation of cashmere growth patterns, and its interplay with non-coding RNAs and the gut–skin axis. Recent advances highlight melatonin’s dual role in enhancing antioxidant capacity (via Keap1-Nrf2) and modulating gene expression (e.g., Wnt10b, CTNNB1) to promote hair follicle proliferation. By integrating multi-omics insights, we construct a molecular network of melatonin’s regulatory mechanisms, offering strategies to improve cashmere yield and quality while advancing therapies for human alopecia.

Melatonin’s capacity to improve cashmere production and quality in goats is well established, but its underlying mechanisms, particularly those concerning the gastrointestinal microbiome, remain inadequately understood. This study aims to elucidate the effects of melatonin implantation on the production performance, blood biochemical parameters, nutrient digestibility, and gastrointestinal microbiome of Liaoning cashmere goats. Thirty newborn Liaoning cashmere goat lambs were selected and randomly assigned to control and melatonin groups using a paired test design. The melatonin group received three melatonin implantations at 15, 75, and 135 days of age, respectively, with a dosage of 2 mg/kg body weight, while the control group received no treatment. Digestive metabolism tests were conducted at 150 and 300 days of age; prior to these tests, blood, rumen fluid, and rectal feces were collected. Apparent nutrient digestibility and blood biochemical indexes were determined, and rumen fluid and rectal feces were analyzed using microbial 16S rRNA sequencing. The results indicated that melatonin significantly reduced daily weight gain and body weight at 60 days (p < 0.05) while significantly increasing daily weight gain at 300 days (p < 0.05). Additionally, it significantly increased cashmere length and reduced its fineness (p < 0.05). Melatonin significantly enhanced nitrogen deposition (p < 0.05), elevated plasma levels of T-AOC, CAT, GSH-PX, and BUN (p < 0.05), and reduced plasma levels of MDA, GOT, GPT, and AKP (p < 0.05). Moreover, melatonin significantly elevated the microbial Ace and Chao1 indices in rectal feces (p < 0.05), increasing genera beneficial for feed digestion and absorption, including Prevotella, Lachnospiraceae, Ruminococcus, and Synergistaceae (p < 0.05); the abundance of these beneficial genera were positively correlated with improved cashmere production performance, antioxidant activity, and liver and kidney function. In conclusion, melatonin enhances cashmere production by modulating gastrointestinal microbiota, antioxidant activity, liver and kidney function, and nitrogen metabolism in cashmere goats. This study provides a theoretical foundation for melatonin’s role in microbiota modulation, which is essential for promoting high-quality and sustainable development in the cashmere goat industry.

Liaoning cashmere goats is a dual-purpose breed valued for premium cashmere fiber and meat yields, and there is currently a lack of optimized strategies for meat quality, including skeletal muscle development and lipid partitioning. This investigation systematically examines how melatonin administration modulates gastrointestinal microbiota and antioxidant capacity to concurrently enhance skeletal muscle hypertrophy and redirect lipid deposition patterns, ultimately improving meat quality and carcass traits in Liaoning cashmere goats. Thirty female half-sibling kids were randomized into control and melatonin-treated groups (2 mg/kg live weight with subcutaneous implants). Postmortem analyses at 8 months assessed carcass traits, meat quality, muscle histology, plasma metabolites, and gut microbiota (16S rRNA sequencing). Melatonin supplementation decreased visceral adiposity (perirenal, omental, and mesenteric fat depots with a p < 0.05) while inducing muscle fiber hypertrophy (longissimus thoracis et lumborum (LTL) and biceps femoris (BF) with p < 0.05). The melatonin-treated group demonstrated elevated postmortem pH₂₄h values, attenuated muscle drip loss, enhanced intramuscular protein deposition, and improved systemic antioxidant status (characterized by increased catalase and glutathione levels with concomitant reduction in malondialdehyde with p < 0.05). Melatonin reshaped gut microbiota, increasing α-diversity (p < 0.05) and enriching beneficial genera (Prevotella, Romboutsia, and Akkermansia), while suppressing lipogenic Desulfovibrio populations, and concomitant with improved intestinal morphology as evidenced by elevated villus height-to-crypt depth ratios. These findings establish that melatonin-mediated gastrointestinal microbiota remodeling drives anabolic muscle protein synthesis while optimizing fat deposition, providing a scientifically grounded strategy to enhance meat quality.