Plasma ¹H-nuclear magnetic resonance metabolomics reveals avian responses to long-term seaweed supplementation in two genetic lines of <i>Gallus gallus domesticus</i>

Blood metabolic profile may be useful for assessing bird responses and identifying key biomarkers and pathways linked to host health and production. We used a prebiotic supplement and heat stress in Lohmann LSL-Lite (White) and Lohmann Brown-Lite (Brown) laying hens to investigate the utility of plasma metabolome in understanding chicken physiological responses. In a short-term trial, red seaweed Chondrus crispus (CC) at 3% was offered to 100 laying hens of the two genetic lines for 21 days. In a long-term trial, 240 hens of the same two strains were given 0%, 3% CC, or 0.5% brown seaweed Ascophyllum nodosum for 41 weeks, then assigned to a control or heat-stress period for 4 weeks. Seaweed supplementation induced the greatest metabolite changes, affecting 50 of 57 compounds, while genetic strain induced the least metabolic change (30 compounds, p &lt; 0.05). Heat stress affected 40 metabolites ( p &lt; 0.05). The short-term inclusion of CC impacted more pathways than the long-term (nine versus four). Heat stress and genetic strain were associated with four and two metabolic pathways, respectively. These results suggested that metabolomics could be used in poultry to identify pathways that explain the effects of genetic and environmental factors linked to chicken health and production.