TITLE:
Effect of Natural Feed Supplement on Methane Mitigation Potential and Performance in Holstein Bull Calves
AUTHORS:
Tassilo Brand, Matthias Miller, Deepashree Kand
KEYWORDS:
Calves, Methane Emission, Mootral, GreenFeed
JOURNAL NAME:
Open Journal of Animal Sciences,
Vol.11 No.2,
April
20,
2021
ABSTRACT: Introduction of solid feeds in the ration of calves has been shown to increase rumen size
and stimulate rumen fermentation. With the initiation of bacterial fermentation
in the rumen, the intermediary metabolism moves from a glucose-based to a volatile
fatty acid-based metabolism, which releases methane. MootralTM
has been identified as a promising plant-derived feed supplement to reduce methane
emission in dairy and beef cattle. Therefore, the present study aimed at quantifying
and mitigating the methane emissions in calves until the slaughtering age of 28
weeks. The study consisted of 20 Holstein bull calves at a commercial farm, assigned
randomly into 2 groups (control n = 10; treatment n = 10), for 2 weeks of adaptation
and 8 weeks of sample collection. The calves were fed an increasing amount of milk
replacer and ad libitum wheat straw. Mootral
was fed once a day to the treatment calves. Methane was measured using GreenFeed
units where concentrate feed was offered as bait. The calves were weighed at the
start and every four weeks during the experiment. The calves in the treatment group
had lower methane emissions (54 g/d) compared to the control group (70 g/d), a reduction
of 22.8%. In contrast, carbon dioxide emission and dry matter intake did not differ
significantly between the study groups. Moreover, no negative impact on the average
daily weight gain and carcass weight was observed in Mootral fed calves. Although
the methane emission (g/kg body weight) was lower in treatment than in the control
group, the absolute difference between the groups narrowed with increasing age of
the calves. The results suggest a need to increase the dose in line with the increased
body weight and intake of the calves. In conclusion, Mootral effectively reduced
methane in calves. Further trials to determine the optimal dose for calves are warranted,
and as well studies to investigate if interventions (such as Mootral) applied at
an earlier life cycle stage would have an impact on methane emissions at later stages
of cattle’s life, would be of scientific interest.