Pre-weaning milk replacer (MR) feeding program is a key factor affecting the health and welfare of lambs during their weaning. Weaning stress is well known as an inducement that negatively impacts the immune system of young ruminants, whose physiological and immune state is closely linked to the community of microbiota in their intestines. This study had two objectives: 1) To evaluate the innate immune response to weaning stress at both the physiological and molecular level; 2) To investigate changes to the jejunal chyme and mucosal adhesive microbiota between the control and high plane of MR groups. In this experiment, the plasma concentrations of cortisol, norepinephrine (NE) and tumor necrosis factor-α (TNFα) were higher in the C than the H group (P < 0.05), as was the expression of pro-inflammatory cytokines such as TNFα and CXCL8 (P < 0.05) in plasma. In jejunal tissue, the expression of TLR4 and TNFα were also higher in the C group (P < 0.01); histopathology showed the H group had lower lymphocyte infiltration. In the C group, however, major pathological changes were associated with extensive infiltration of lymphocytes, eosinophils, and neutrophils. Principal component analysis indicated the lamb immune response was influenced by weaning stress and modulated by the MR treatments. 16S-rRNA sequencing was used to evaluate jejunal mucosa and chyme bacterial diversity and composition. The C group’s chyme had a greater alpha index (ACE: P = 0.095; Chao1: P = 0.085) than H group. In jejunal mucosa, the relative abundance of Plesiomonas was 4-fold higher (P = 0.017) in the C than the H group. This study’s results revealed that weaning stress induced alterations to the lambs’ immune system that lasted beyond the 21 d measured, and that a long-term inflammatory response effect was evidenced by changes in their hematological and expressed pro-inflammatory cytokines. Pre-weaning with a differing MR allowance resulted in complicated biological responses and compositional changes to the lambs’ jejunal microbiota. Clearly, an intensive MR feeding program induced a milder immunity response and lower relative abundance of pathogenic bacteria when compared with the traditional feeding program.

The nettle Urticacannabina (U.cannabina) is not only a functional edible food for humans but also a potential alternative feed resource for poultry, providing protein, fatty acids, vitamins, and minerals. The present study was conducted to evaluate the effects of dietary U.cannabina on the production of high-quality eggs with enriched n-3 polyunsaturated fatty acids (PUFA) and lower cholesterol contents. One hundred and twenty laying hens were assigned to three groups [control, 15% alfalfa meal supplementation (TRTA), and 15% U.cannabina supplementation (TRTU)]. The results showed that the feed intake, yolk color, and shell thickness were increased (p < 0.05) in the U.cannabina group. Moreover, cholesterol contents of the yolk and serum were lower in the U.cannabina group (p < 0.05). The total n-3 PUFA concentration in the yolk was increased while the ratio of n-6/n-3 was reduced in the U.cannabina group (p < 0.01). In conclusion, the dietary inclusion of U.cannabina increased shell thickness, yolk n-3 PUFA levels, and yolk color, and reduced cholesterol contents of the yolk and serum without any negative impacts on health or laying performance.

Feeding regimens influence the fatty acid composition of animal-derived products. However, there is limited information on the effect of feeding regimens on the blood fatty acid composition and metabolic pathways of ruminant animals. In this study, 30 Wujumqin sheep were randomly assigned to three groups, PF (pasture feeding), PSF (pasture feeding plus corn supplementation) and BF (barn feeding), to examine the effects of feeding regimens on blood fatty acid composition and metabolic pathways through a metabolomic approach. The results showed that the BF sheep had increased serum n-6 polyunsaturated fatty acids levels, while the PF and PSF sheep had increased serum n-3 PUFA levels. Compared to the BF and PSF sheep that were fed ground corn, the PF sheep that only ate natural grass had up-regulated serum DHA levels. Meanwhile, blood metabolites from linoleic acid and arachidonic acid, including pro-inflammatory products (20-HETE, LTs, TX etc.) and anti-inflammatory products (LXB4, DHETs, HPETEs etc.) were elevated in the BF group. It was found that, compared to grazing, concentrate supplement feeding regimens, including either grazing plus supplements or feeding indoors, down-regulated blood n-3 PUFA biosynthesis and up-regulated the blood inflammatory compound metabolism by n-6 PUFA.

Nettle is not only a nutrient-rich forage but also possesses the potential to act as a nutritional and physiological regulator. This study investigated the effects of supplementing nettle hay into the total mixed rations (TMR) on milk yield, milk composition, antioxidant capacity, immune function, and plasma metabolome in dairy cows. Twenty multiparous Holstein cows with similar days in milk (102 ± 8 d), milk production (39 ± 3 kg/d), milk fat (3.78 ± 0.55%), and milk protein (3.24 ± 0.28%) were randomly assigned to two dietary treatments: a control group (AH group, n = 10) receiving a TMR with 10.5% alfalfa hay and a nettle group (NH group, n = 10) receiving a TMR with 10.5% nettle hay. The experiment lasted for 80 d, including a 20 d pre-feeding period. Milk yield and overall composition remained consistent across the groups. However, the NH group exhibited a significant decrease in milk aspartic acid (P = 0.025) and a concomitant increase in arginine (P = 0.031). Nettle supplementation significantly reduced blood aspartate aminotransferase levels (P = 0.005) and improved antioxidant status, as evidenced by a higher total antioxidant capacity (P = 0.039) and total superoxide dismutase activity (P = 0.016), along with lower malondialdehyde (P = 0.018). The metabolome analysis identified 1143 differential metabolites using the positive ionization mode and 1253 differential metabolites using the negative ionization mode. KEGG analysis revealed significant enrichment of differential metabolites in arachidonic acid, linoleic acid, and amino acid metabolism pathways. Lysophosphatidylcholines and enterolactone displayed a significant negative correlation with blood aspartate aminotransferase levels (r < −0.5, P < 0.05) and interleukin-6 levels (r < −0.5, P < 0.05). In conclusion, nettle supplementation significantly influenced the immune and antioxidant capacities of dairy cows by altering the blood metabolome profile. Lysophosphatidylcholines and enterolactone are proposed as potential biomarkers for evaluating the physiological and immune effects of nettle supplementation. Further research is warranted to elucidate the specific mechanisms underlying these effects and optimize the feeding regimen for optimal outcomes.