“Hemp (Cannabis sativa L.) products have gained attention in poultry nutrition for their rich content of polyunsaturated fatty acids (PUFAs), bioactive compounds, and potential functional benefits. However, findings on their impact on laying-hen performance, egg quality, and yolk fatty acid profiles have been inconsistent.
This meta-analysis aimed to evaluate the effects of dietary hemp products on laying-hen performance, egg quality traits, and yolk fatty acid composition, while exploring potential sources of heterogeneity across studies.
A comprehensive literature search identified 21 studies that met the inclusion criteria. A random-effects model was used to calculate standardized mean differences (SMDs) with 95% confidence intervals (CIs) for various outcomes, including production performance, egg quality, and yolk fatty acid profiles. Subgroup and meta-regression analyses assessed the influence of factors such as inclusion level, hen age, and hemp product type.
The results showed that hemp supplementation had no significant effect on hen-day production, egg mass, feed conversion ratio, or feed intake. However, yolk redness (SMD = 4.40; 95% CI: 2.46, 6.33; p < 0.001) and yellowness (SMD = 4.45; 95% CI: 2.75, 6.16; p < 0.001) were significantly enhanced. Hemp feeding also increased n-3 PUFA levels in egg yolk, including C18:3n3, C20:5n3, and C22:6n3, while reducing saturated and monounsaturated fatty acids. Subgroup analysis indicated that inclusion levels > 10% and hen age ≤ 25 weeks were associated with slight reductions in hen-day production, whereas older hens (>25 weeks) showed increased egg weight.
In conclusion, hemp products can enrich yolk pigmentation and n-3 PUFA content in eggs, supporting the production of functional, value-added eggs without compromising the laying-hen performance.”
https://pubmed.ncbi.nlm.nih.gov/40723525/
“This meta-analysis underscores the potential of hemp-derived products as functional feed ingredients in laying-hen nutrition. Supplementation with hempseed, hempseed cake, or hempseed oil was found to significantly enhance yolk pigmentation and enrich long-chain omega-3 fatty acids, particularly DHA, without adversely affecting key performance metrics such as hen-day egg production, egg mass, or feed conversion ratio when inclusion levels are appropriately managed. Subgroup analyses revealed that inclusion levels above 10% and use in younger hens (≤25 weeks) may negatively impact productivity, whereas older hens exhibited improved egg weight. Among the different hemp product types, hemp oil demonstrated the most pronounced benefits for yolk coloration and fatty acid enrichment.”