Effects of feeding barley on growth performance and diet nutrient digestibility of weaned pigs

Abstract Text: Cereal grains vary considerably in price and quality. Barley is usually priced 10-20% lower than wheat in Western Canada. Wheat contains more NE than barley and is preferred during the energy-dependent phase of growth. We investigated if feeding of low quality barley (LB) will reduce growth performance and diet apparent total tract digestibility (ATTD) in weaned pigs compared to high quality barley (HB) or hard red spring wheat. Diets contained 20% soybean meal and 62% cereal grain varying in NE (Mcal/kg) content (2.33, 2.23 and 2.44 for HB, LB, and wheat, respectively). Grain constituents used to predict the NE value were predicted by near infra-red reflectance spectroscopy. Starting 1 wk after weaning at 28 d of age, 280 weaned pigs (initial BW 8.7 ± 0.9 kg) were fed diets for 3 wk (d 1 to 21). Five pelleted diets were formulated as (Mcal NE/kg using canola oil; g standardized ileal digestible (SID) Lys/Mcal NE using synthetic AA): A) wheat (2.39, 4.47); B) HB (2.39, 4.46); C) LB (2.33, 4.57); D) LB, corrected for NE (2.39, 4.45); and E) LB, low NE (2.25, 4.68). Feed intake and BW were measured weekly to calculate pen ADFI, ADG, and G:F. Feces were collected to calculate diet ATTD of DM, GE, and CP and diet DE and NE value. Compared with diet A and B, pigs fed diet D had greater (P < 0.05) ADFI (542, 596 vs. 652 g/d), ADG (365, 403 vs. 443 g/d) and G:F (0.646, 0.662 vs. 0.681); while differences were not observed among diets C, D, and E. Pigs fed diet A had ADFI and ADG lower (P < 0.05) than pigs fed other 4 diets. The ATTD of CP, GE, and DM of diet E (77.0, 77.3, 76.9%) was greater (P < 0.05) than of diet B (72.4, 74.3, 74.0%) and C (74.9, 75.3, 74.7%) and similar to diet D (75.9, 76.4, 75.8%), respectively. Pigs fed diet A had ATTD of GE greater (P < 0.05) than pigs fed other 4 diets. The DE value (Mcal/kg) of diet D (3.62) and E (3.55) were greater (P< 0.05) than of diet B (3.46) and lower than of diet A (3.71). In conclusion, feeding LB instead of HB and wheat did not reduce growth performance. Feeding barley instead of wheat is economical and achieved greater growth performance even though diet energy digestibility was lower. 

Keywords: barley, pig, digestibility