Élisabeth Chassé1, Mirka Thorsteinsson1,4, Mihai Victor Curtasu1, Marco Battelli2, Annette Bruhn3,4 and Mette Olaf Nielsen1,4
1Department of Animal Science, Aarhus University, Foulum, Denmark
2Dipartimento di Scienze Agrarie e Ambientali – Produzione, Territorio, Agroenergia, Università degli Studi di Milano, Milano, Italy
3Department of Ecoscience, Aarhus University, Aarhus, Denmark
4Center for Circular Bioeconomy, Aarhus University, Foulum, Denmark
In previous in vitro experiments simulating rumen fermentation, it has been found that two Fucus species. possess significant ability to suppress methane formation associated with rumen fermentation of feeds. In contrast to Asparagopsis species the anti-methanogenic activity of Fucus species cannot be ascribed to halomethanes. The aim of this experiment is to investigate, whether the anti-methanogenic properties of the Fucus spp. can also be obtained in vivo, considering the dynamic flow-through system in the forestomachs of ruminant animals. Three multi-cannulated (rumen, duodenum and ileum) Danish Holstein dairy cows are used in a 3 x 3 Latin square design experiment, with three periods of three weeks duration, where cows are fed three different total mixed ration (TMR): a control TMR without seaweed and two rations where the control TMR has been diluted on dry matter basis with 4% of either of the two Fucus species. The effects of adding seaweed to the rations are assessed for feed intake, feed digestibility, milk production, and methane emission. The first 14 days of each period is assigned to adaptation to the diet, followed by three days of digesta sampling and subsequently four days of gas exchange measurements in respiration chambers. Data will be available for presentation at the symposium.