The effect of feeder space access and crumble- or pellet-to-fine ratio on 38-day-old broiler performance

Abstract

SUMMARY Research conducted at universities often exposes broilers to conditions that are less stressful than encountered in typical commercial production. Research utilizing small floor pens and industry-style feed pans frequently provides much greater feeder space access than broilers receive in commercial barns. Feeder space access could be an important variable influencing research results, especially when coupled with crumble- or pellet-to-fine ratio variations. The objective of the study was to assess the effects of feeder space and crumble- or pellet-to-fine ratio on broiler performance. The study utilized a 2 × 2 factorial arrangement in a randomized complete block design using the main effects: high or low crumble- or pellet-to-fine ratio (70:30 vs. 40:60) and increased or industry feeder space access (5.9 cm/bird vs. 1.2 cm/bird). Diets met Agristat nutrient values and were pelleted at the West Virginia University pilot feed mill. A total of 1,840 Hubbard × Cobb straight run broilers were randomly placed in one of 40 pens. Broilers and feed were weighed to calculate feed intake (FI) per bird, live weight gain (LWG) per bird, ending bird weight (EBW), and mortality corrected FCR, percent mortality, and pen coefficient of variation for EWB (d 38). The effect of crumble- or pellet-to-fine ratio depended on the amount of feeder space for overall one to 38 d FI. High crumble- or pellet-to-fine ratio increased feed intake with the effect being more pronounced with increased feeder space. Broilers fed a high crumble- or pellet-to-fine ratio from d one to 38 demonstrated increased LWG and decreased FCR (P