Formaldehyde treated diets for drought feeding of sheep

Abstract

Three experiments are reported in which formaldehyde treatment of various components of survival rations was examined. In experiment 1, Merino weaner ewes were fed survival diets composed of either wheat or sorghum grain with meat and bone meal and low quality roughage. The grain and the meat and bone meal components were treated or untreated with formaldehyde (HCHO), and half the animals were treated with vitamin A. Both HCHO treatment of the grain and vitamin A treatment significantly increased liveweight gains over the 20-week experimental period. There was no wool growth response to HCHO treatment but wool growth rates were higher in sheep on the wheat based diets. Vitamin A treatment had no effect on survival rates, which were, however, lower in sheep on wheat diets. In experiment 2, similar sheep, maintained on a basal diet of low quality sorghum silage, were supplemented with meat and bone meal treated or untreated with HCHO and half the sheep were treated with vitamin A. HCHO treatment resulted in a lower rate of liveweight loss but only for the first 30 days of the experiment. Neither wool growth rates nor survival rates were affected by HCHO or by vitamin A treatment. In experiment 3, Merino wethers were used and the effectiveness of HCHO treatment of either wheat or sorghum grain diets was further examined. HCHO treatment had no effect on either liveweight or clean wool production, which was, however, higher in sheep on wheat based diets.