Impact of inulin on production of methane, carbon dioxide and gastrointestinal canal functionality in calves

Abstract

Ruminants produce a large amount of methane (CH 4 ) and carbon dioxide (CO 2 ) in their foregut. These gases cause greenhouse effect. There are a lot of studies about different feed additives which can reduce the production of greenhouse gases in ruminants. Prebiotics can also change the amount of bacteria in animal gastrointestinal tract and reduce the occurrence of diarrhoea. The aim of this study was to test whether the prebiotic inulin affects the production of CH 4 and CO 2 in calves' rumen and whether it affects the bacteria count in the rumen fluid and bacterial overgrowth in intestines. We used the flour of Jerusalem artichoke (Helianthus tuberosus L.) containing 50% of inulin. Approximately fifty days old, Holstein Friesian crossbreed calves were used in this study. Eight were in the control group, 8 received 12 g of flour and 8 received 24 g per day. On the 28 th and 56 th day of the research, we measured the amount of CH 4 and CO 2 in calves' rumen, took rumen fluid samples for bacterial analysis and urine to measure the level of phenol and indican. We concluded that adding the flour of Jerusalem artichoke at doses 12 g and 24 g did not significantly impact the production of CH 4 and CO 2 in calves' rumen, the prebiotic inulin may suppress the growth of anaerobic microorganisms in the rumen at concentration 12 g of inulin reaching 56 th day of experiment. The amount of phenol and indican in calves' morning urine did not correlate with the faecal consistency of calves.