Can dietary quality of free-ranging ungulates be simply determined from faecal chemistry?

Feeding trials with a number of ungulate species in South Africa led Erasmus et al. (1978) to propose that linear relationships might exist between content of diet and content of dung for a number of key dietary nutrients, and that thus chemical analysis of dung might provide a simple method for determining available forage quality. These suggestions are tested, using three temperature ruminant species (fallow, sika and roe deer) and one non-ruminant (free-ranging domestic horses). Dietary content of dung in terms of a number of nutrients was related to dietary quality of ingesta (reconstructed from faecal dissection). Significant linear relationships were found amongst the deer for N, K, Ca content of diet and dung, but not for P, Mg or lignin.; a linear relationship was established in the horse only for lignin. The implications of these results for simple determination of forage quality are discussed.