Production, milk iodine, and nutrient utilization in Jersey cows supplemented with the brown seaweed Ascophyllum nodosum (kelp meal) during the grazing season

This study investigated the impact of Ascophyllum nodosum (kelp meal) supplementation in grazing dairy cows, focusing on intake, production, and iodine metabolism.
Cows receiving seaweed showed increased pasture intake and a tendency toward higher total feed intake, but milk yield and composition remained unchanged.  Blood metabolites such as cortisol and thyroid hormones were also largely unaffected, indicating no major physiological disruption.
As in previous work, supplementation led to higher milk iodine concentrations, which varied across grazing periods and exceeded the recommended human consumption threshold in one of them.
The authors emphasize that, despite some intake effects, the lack of production response means economic considerations are critical when using seaweed in grazing systems.