Comparative digestive ability, and response to urea supplementation of a whole barley grain and barley straw diet, of goats and sheep

Abstract

The world population of sheep and goats was estimated by the F.A.O. (1978) to be 1,055 and 435 millions respectively. Over half of the world sheep flock and nearly 95% of the goat herd is situated in developing countries. The poor quality of forages available in these areas for most of the year is well documented (El Hag 1976, Gihad 1976) and is recognized to be a major limiting factor to animal production. The lack of scientific and technical knowledge about goat husbandry in comparison with that known about other ruminants (Morand-Fehr, Bourbouze and de Simiane 1981), is a glaring omission considering the numbers of people dependant on goat farming within developing countries.

Of the few papers written concerning the comparative digestive ability of goats and other ruminants, none have presented unequivocal evidence and it was felt that an experiment using a 2x2x2 factorial change-over design would have much to contribute to the current controversy in this area.

Urea supplementation of poor quality forage diet is a simple, effective method of providing a nitrogen supplement to a low protein diet. The work done in this area has rarely included goats and it was felt appropriate to include an investigation into goat and sheep response to urea within this comparative trial.