Supplemental material for: Methane category, immune response, feed efficiency, and rumen microbial community in lactating dairy cows

The supplementary material provides information for the article published in Journal of Dairy Science, entitled \"Methane category, immune response, feed efficiency, and rumen microbial community in lactating dairy cows\". This study aims to assess relationships of enteric methane (CH4) yield (g/kg of dry matter intake (DMI)) with immune response, feed efficiency (energy corrected milk (ECM)/DMI), and rumen microbiome in dairy cows, both in early and in late lactation. The DMI, body weight, ECM yield, and CH4 emission were measured in respiration chambers in early (n = 20, 32 ± 7 days in milk (DIM)) and non-pregnant late lactating (n=14, 359 ± 90 DIM) multiparous Holstein cows. The in vitro immune response was studied in response to (1) lipopolysaccharide using whole blood, and (2) phytohemagglutinin and concanavalin A using peripheral blood mononuclear cells. The DNA was extracted from rumen content samples (esophageal tubing) for 16S rRNA microbial analysis. Cows were divided retrospectively into an equal number of cows with low (LMY) and high (HMY) CH4 yield within each lactation group.