Effects of particle size and feed form on broiler performance

A study was conducted to evaluate the effect of feed form and corn particle size on broiler performance. Previously, broilers had an improvement in feed conversion when fed pelleted (P) diets as compared with mash (M) diets, but results for the effects of particle size were not as clear. This experiment was a 2 × 2 factorial design of feed form (P and M) and corn particle size (300 and 600 μm). Each of 8 replicate pens had 16 males and 16 females for each of the 4 interactions. The corn and soybean meal starter P diet was crumbled, whereas the grower and finisher P diets were fed as pellets. The average corn particle size in the 300 and 600 treatment diets was 267 and 570 μm, respectively. Pellet durability index of the P300 diets and P600 diets, produced with a hammermill equipped with either a 1.6- or 7.9-mm screen, averaged 88 and 84%, respectively. The chicks fed the P300 diet exhibited a significantly higher BW to 21 d, but the difference diminished thereafter. The 44-d BW of broilers in the P treatment was higher and FCR was better than for those fed M diets, as expected. No significant difference was observed in the FCR of birds fed the P300 (1.88) or P600 (1.85) diets at 44 d. On the basis of these results, broilers performed better when fed the P diets, and they demonstrated a positive BW response to feeding finer particles up to 21 d.