1.Effects:

As a bioactive component of natural herbal medicine, curcumin demonstrates the following:

1.1 Pharmacological effects: Anti-inflammatory effects: By inhibiting signaling pathways such as nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK), it reduces the release of pro-inflammatory factors including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β). Additionally, it suppresses the activity of inflammation-related enzymes like cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS), thereby alleviating both acute and chronic inflammatory responses.

1.2 Antioxidant effects: It directly neutralizes reactive oxygen species (ROS) and hydroxyl radicals, while activating the nuclear factor E2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway to enhance the activity of endogenous antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px), thereby boosting the body's antioxidant capacity.

1.3 Broad-spectrum antibacterial activity: It inhibits Gram-positive bacteria (e.g. Staphylococcus aureus, Streptococcus), Gram-negative bacteria (e.g. Escherichia coli, Salmonella) and fungi (e.g. Candida albicans). The mechanism includes disrupting bacterial cell membrane integrity, inhibiting nucleic acid and protein synthesis, and inhibiting bacterial biofilm formation, reducing the risk of drug resistance.

1.4 Immune regulation: Promote the proliferation and differentiation of T lymphocytes and B lymphocytes, enhance the phagocytic function of macrophages, promote the secretion of immune-enhancing factors such as interferon-γ (IFN-γ) and IL-2, and regulate immune balance to reduce the damage of excessive immune response to tissues.

Other effects: It also has a variety of biological activities, such as protecting liver (improving liver injury, promoting the repair of hepatocytes), antiviral (inhibiting virus replication and invasion), and regulating metabolism (improving the disorder of sugar and lipid metabolism).

2. Application in poultry farming:

2.1 Curcumin enhances production performance in laying hens

Egg production rate increasedS：pecifically, 50mg/kg curcumin increased peak egg production by 5.7%, with particularly significant results observed in older hens (>60 weeks of age), achieving a 7.3% improvement.

Prolonged egg-laying cycle: Continuous supplementation can extend the effective egg-laying period by 2-3 weeks, delaying ovarian decline by regulating ovarian antioxidant levels.

Egg yolk color intensity: Enhanced by 1.5-2.0 levels using Roche colorimetric fan. Eggshell thickness: Increased by 12.5% (reaching 0.42mm).

Egg breakage rate: Reduced by 30%-40%.

2.2 Quantitative effects of curcumin on broiler growth performance

Weight gain: Adding 0.5%-1% curcumin increased broiler weight by 5%-10% at 42-day age. A U.S. study showed a 3.8% weight gain (P<0.05) at 200mg/kg dose, while a Brazilian study reported a 9.2% weight gain in the 1% curcumin powder group.

Feed conversion ratio ：(FCR) improved by 3%-8%. When the supplementation reached 0.5%, the feed-to-meat ratio decreased by 7.5%, with more significant effects under high-density farming conditions .

Control of mortality: The mortality was reduced by 1.5%-3% at the dosage of 100-150 mg/kg, which was mainly achieved by enhancing the intestinal barrier function and immune response.