Abstract

1. Male broilers (0 to 35 d) were given foods with two types of yellow sorghum substituted for maize in isonutrient diets. Sorghum‐based foods were also supplemented with extra phosphorus, to provide a total P of about 8 g/kg; the P being from either orthophosphoric acid or food grade dicalcium phosphate.

2. Both sorghums depressed growth and food:gain ratio and increased the incidence of locomotor disorder to about 0.50 (maize control = 0). Sorghum from Sudan, with higher concentrations of both tannin and phytate, caused more severe anti‐nutritive effects than sorghum from Egypt.

3. Within the limits of statistical significance the growth depressing effect of sorghum was completely reversed by extra P. With the more toxic Sudanese sorghum this amelioration was numerically less than complete (growth = 0.94, maize control=l). Locomotor disorders were also virtually, but not completely, eliminated by phosphorus treatment.

4. Treatment of sorghum by dry‐mixing with dicalcium phosphate could form the basis of a simple and economic method for extending the use of high‐tannin sorghum in poultry foods. The mode of action of the treatment remains to be determined.