A preliminary study of effects of the red Bonnemaisonia hamifera seaweed on methane emission from dairy cows

The red seaweed Bonnemaisonia hamifera has shown potential as a CH4 mitigating feed additive invitro, and hence, this pilot study aimed to investigate the potential of the seaweed when fed to dairy cows. The study was conducted as a 4 x 4 Latin square using 4 Danish Holstein cows with 4 periods of 7 d where the cows were placed in respiration chambers for the last 3 d. Milk yield and feed intake were recordeddaily. The cows were fed a TMR without B. hamifera (CON) or the same diet with the addition of, onDM basis, 0.33% (LOW), 0.66% (MED), and 1% (HIGH) B. hamifera. Rumen samples were collected through the cannula once per period. RNA was extracted and meta transcriptome sequenced.