The influence of the variety of barley and level of nitrogen fertilisation on the digestibility and metabolisable energy value of barley meal in the pig

Metabolism studies were carried out with 45 kg pigs to examine barley meal from the varieties Golden Promise, Maris Mink, Lami, Zephyr and Abacus, all with similar nitrogen (N) content, and barley meal from the variety Zephyr which had received four different levels of N fertilisation. There were no significant differences (P > 0.05) between varieties for the apparent digestibility coefficients of gross energy (GE) and proximate constituents, the least significant difference for GE and N being 0.025 and 0.089 of the respective means. The mean digestible energy (DE) and metabolisable energy (ME) values were 14.48 and 14.07 MJ/kg dry matter (DM). The mean apparent digestibility of N was 0.685. The apparent digestibility coefficients of GE and N of meal from the variety Zephyr increased with N content. The increase in DE value with N content could be attributed to the increase in N digestibility.