The effect of chemical curing with paraquat on the intake and digestibility of phalaris pasture

Abstract

A phalaris-dominant pasture received three treatments: no spray, sprayed with paraquat herbicide at early head emergence (spray 1) and at 50 per cent flowering (spray 2). A series of digestibility trials from November 1966 to March 1967 measured the voluntary intakes by sheep, and the nutrient digestibilities of the material resulting from each treatment. The level of crude protein in the sprayed pasture remained higher throughout the summer than in the unsprayed pasture. However, digestibility of crude protein was only higher for sprayed treatments during January 1967. Spraying did not significantly affect intakes or dry matter and crude fibre digestibilities throughout the period. Sheep receiving spray 2 pasture lost more weight than those receiving pasture from the other two treatments.