Effects of feed form (pellet or mash), corn particle size, and <i>Bacillus</i>-based probiotic supplementation on performance traits and digestive tract health of broiler chickens

Abstract

A total of 720 Ross 308, male broiler chicks were used to study the effect of feed form, corn particle size, and probiotic supplementation as a completely randomized block design with 2×2×2 factorial arrangement (eight treatments and five replications). The factors included the type of feed (pellet or mash), the average size of corn particles (590 and 1220 μm), and the addition or absence of a probiotic (DIPro) to the diet. At the end of the experiment, relative weights (% of BW) of abdominal fat and gizzard were calculated as a percentage of live weight. Using pellets increased the body weight gain (BWG), feed intake (FI), and improved feed conversion ratio (FCR). Feeding coarse corn particles substantially reduced the body weight gain and increased the feed conversion from 1–10, 25–42, and 1–42 days of age. Feed intake reduced from 1–42 d and 42–25 d by consuming coarse corn particles. The use of probiotics increased feed intake and body weight gain from 25–42 and 1–42 d. The pelleted diet increased gizzard and proventriculus pH, whereas coarse corn particles reduced pH. The pelleted feed decreased the relative weight of the gizzard and increased the abdominal fat percentage. Coarsely ground corn increased the abdominal fat and gizzard percentage. Probiotic supplementation improved feed intake, body weight gain, and feed conversion from 1–42 d. Pelleted feed plus probiotics and a 590-μm particle size produced the best performance in broilers.