Performance of steers fed grain sorghum (Sorghum bicolor) of varying sorghum midge (Contarinia sorghicola) resistance

Abstract

This experiment examined the association between the level of sorghum midge resistance of a grain sorghum hybrid and its ultilisation by cattle. Twenty-five Hereford steers were placed in individual pens and fed a feedlot ration (80% grain) for 8 weeks containing 1 of the following grain sorghum hybrids: Pacific 810, DK55plus (susceptible to midge); Barrier (low resistance to midge); AQL39/QL36, DK470 (moderate resistance to midge). There was no significant (P>0.05) difference between the hybrids in dry matter intake, liveweight gain, feed conversion efficiency, apparent nitrogen digestibility, and digestibility of the dry matter. No tannins were detected in the grain of any of the hydrids. It was concluded that the development of grain sorghum hybrids resistant to sorghum midge will not affect the utilisation of the grain in steers.