Effects of variety, soil type and nitrogen fertilizer supply on the nutritive value of barley for growing-finishing pigs

Abstract

The effects of variety, soil type and nitrogen (N) fertilizer supply on the nutritive value of barley were studied with chemical analysis, in vitro digestibility and a growth experiment on 240 growing/finishing pigs (live-weight 25-95 kg). Twelve barley batches were formed from three varieties (two-rowed Kustaa and six-rowed Arra and Pokko) grown on mould or clay soil and fertilized with either a low or normal level of N (43 or 71 kg N/ha to mould soil and 76.5 or 110 kg N/ha to clay soil). In the growth experiment all the diets contained similar amounts of barley and soya bean meal (845/120 g/kg). Variety Arra contained 21 g/kg more CP than did Pokko or Kustaa. The N fertilizer supply slightly increased the CP content of the barley samples (133 vs. 141 g/kg) but decreased the amount of lysine in the protein (31 vs. 29 g/160g N). Regression equation showed that CP and beta-glucan were positively and neutral detergen fibre content negatively related to the in vitro digestibility of N in barley samples. The content of CP and the in vitro digestibilities of dry matter and N were highest in var. Arra. The daily gain and feed conversion ratio (FCR) of the pigs on Arra-based diets was better than that of those on Kustaa or Pokko (P