Abstract
A series of experiments was carried out to compare the various methods for determining the forage intake of grazing animals. Two Hereford heifers were used in the following trials. Trial 1: During the 11-day trial period, the heifers remained in their respective stantions and were supplied with freshly harvested green forages. The animals were given 10g of chromic oxide in a gelatin capsule twice daily, at 8a.m. and 4p.m. Total fecal collections were made manually. Chromogen contents of the green forages and feces were determined by the usual method. The fecal samples were dried and analyzed for chromic oxide. Two indicator methods, chromogen and chromogen-chromic oxide method, gave good estimations of forage intake (Table 1). Trial 2: When the heifers were confined to a pasture, forage intake was determined by these indicator methods. The value estimated by the chromogen-chromic oxide method showed close agreement with that by the chromogen method (Table 1). Trial 3: The chromogen-chromic oxide method and a forage meter, an electronic capacitance meter for estimating forage yields, were used to estimate the forage intake of the grazing heifers. The forages intake estimated by the forage meter was comparable to that by the indicator method (Table 2). The correlation coefficient between these estimated values was 0.61 and was statistically significant at the 5% level. In view of the result it seems likely that the forage meter can be used for estimating the forage intake of grazing animals.
