Pulse Brain · Growing Health Evidence Index
Tier 3 — Observational / field trialPeer-reviewed

Geographical Variations in Egg Nutrient Density: A Comparative Study of Sustainable Layer Hen Systems in Ohio and Indiana in Late Fall and Early Winter Months

Julianna Adams; Rachel van Duinen; S. Sergin; Chad A. Bitler; Jenifer I. Fenton

Sustainability · 2025

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Summary

This study examines how geographical location and associated forage availability influence the nutritional profile of eggs from regenerative, pasture-raised layer hen systems in two US Midwest states during late autumn and early winter. Sampling across two consecutive years enabled comparison of egg quality metrics — including fatty acids, micronutrients, carotenoids, and yolk pigmentation — between an Ohio farm and an Indiana farm. The findings suggest that regional environmental conditions, including forage type and quality, may drive meaningful variation in egg nutrient density even within broadly similar production systems.

UK applicability

This US-based study is not directly applicable to UK conditions, but the principle that regional forage variation influences pasture-raised egg nutrient profiles is relevant to UK producers and researchers evaluating free-range and regenerative poultry systems, particularly given seasonal variation in UK pasture quality.

Key measures

Yolk colour fan score; fatty acid composition (GC-MS); micronutrient concentrations (commercial laboratory); carotenoid content (colorimetric); polyphenol content (colorimetric); forage nutrient composition

Outcomes reported

The study measured fatty acid profiles, micronutrient concentrations, carotenoids, polyphenols, and yolk colour scores in eggs from two regenerative pasture-raised layer hen farms in Ohio and Indiana, sampled monthly from September to December across two years. It also assessed forage composition to explore links between diet and egg nutrient density.

Theme
Farming systems, soils & land use
Subject
Livestock nutrition & product quality
Study type
Research
Study design
Field trial
Source type
Peer-reviewed study
Status
Published
Geography
United States
System type
Pasture-based poultry
DOI
10.3390/su17073208
Catalogue ID
NRmo3ep4ea-00k

Topic tags

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