Losses from cattle faeces during chemical analysis

Abstract

The effects of drying temperature and method of sample digestion on the determination of nitrogen and dry matter in the faeces of cattle grazing pastures of two different nitrogen contents were examined. Nitrogen loss varied from 8 to 20 per cent depending on the temperatures and associated length of drying time. The variation in the loss between samples from animals grazing the two pastures was small, tending to be higher for the samples taken from animals grazing a higher nitrogen pasture. Sample digestion by the H2SO4-H2O2 method was found to be as satisfactory as the micro-Kjeldahl method. Drying at 100°C for 24 hours gave the least loss of nitrogen. This procedure in conjunction with the H2SO4-H2O2 , digestion is proposed as a routine method for determination of nitrogen in faecal material.