An alternative method of administering alkane markers for estimating intake in dairy cows

Extract

Alkanes have been used for a number of years to estimate food intake in ruminants. The technique requires animals to be dosed with synthetic even-chained alkanes, usually C₃₂ and C₃₆; faecal concentrations of these are then compared with naturally-occurring alkanes, e.g. C₃₃, to estimate intake. Mayes et al. (1986) prepared capsules containing alkanes on shredded paper; Dove et al. (1988) used hard-shell gelatine capsules to administer dosed alkanes. Both methods required animal handling, extra material, like gelatine capsules or paper, and also some laboratory work for preparing alkane solutions, papers and capsules. We report here a less time-consuming method that can be used with dairy cows or other animals offered concentrates separately from a basal ration. The objective of the study was to see how accurately food intake in dairy cows could be estimated when dosed alkanes are administered via a compound feed.