The Effect of Particle Size of Commercial Soybean Meal on Performance and Nutrient Utilization of Broiler Chicks

Abstract

An experiment was conducted to determine the effects of soybean meal (SBM) particle size on broiler performance, particularly P utilization. This experiment utilized a 2 x 2 x 2 factorial design with the following variables: SBM particle size, P level, and diet type, either corn-SBM or semipurified. SBM was obtained from a processing plant before (geometric mean diameter 1,239 microm) and after (891 microm) hammer milling. The P levels were 0.5% total P for deficient diets and 0.7% total P for adequate P diets. The coarse SBM improved bone ash (P < 0.05), gain:feed ratios (P < 0.1), and plasma P levels (P < 0.1). The diets with 0.5% P resulted in overall poorer performance as 16-d BW was reduced, gain:feed ratio decreased, bone ash decreased, and rickets incidence increased. Chicks fed the semipurified diets also had lower 16-d BW, lower gain-to-feed ratio, and lower bone ash. There was a significant interaction between the diet type and the soy particle size when the corn-SBM meal diets were fed because the coarse SBM increased plasma P levels, whereas there was little effect when the semipurified diets were fed. There were also significant interactions observed between these variables on growth and gain:feed ratio in that the coarse SBM elicited a much more dramatic response when incorporated into the semipurified diets as opposed to the corn-SBM diets. The results suggest that large particle size soybean meal may be more efficiently utilized than fine particle size soybean meal.

Abrupt Temporal Fluctuations in the Chicken Fecal Microbiota Are Explained by Its Gastrointestinal Origin

“…This suggests that chickens fed with coarse BSG have a stronger barrier for releasing the lactic acid bacteria through the digestive system than for those fed with fine BSG. This interpretation is in accordance with previous studies showing that feed structure stimulates the gizzard barrier function (1,18). Component 1 (Shigella/E.…”

Phytate degradation in broilers

“…Contrary to our hypothesis, it was not confirmed in the current study that dietary structure the levels of phytate degradation and precaecal P digestibility further improved. The current findings were partly in line to those of Kilburn and Edwards (2004), who observed that feeding coarse maize diet to broilers did not increase the level of P retention, but that the coarse maize diet improved phytate P retention and plasma P levels. In the current study, values for P digestibility (82.8%) and phytate degradation (96.2%) were already very high, which gave not many space for further improvement.…”

“…Among other benefits, the process of continued particle size reduction increases both the number of particles and the surface area per unit volume, allowing greater access to digestive enzymes (Goodband et al, 2002). It was suggested by Kilburn and Edwards (2004) that coarse soybean meal may be more efficiently utilized than fine soybean meal. These authors found interaction between SBM particle size and P level when tested at different dietary P contents (0.7 and 0.5%).…”

Particle size and feed form in broiler diets: impact on gastrointestinal tract development and gut health

“…Nir et al (1994a) reported that when day-old chicks were fed medium and coarse maize particles, gizzard weight increased by 26 and 41%, respectively, compared to those fed fine particles. Kilburn and Edwards (2004) stated that larger particles were retained longer, allowing more time for nutrient digestion and absorption. These benefits were reduced when the diet was fed in pelleted or crumbled form, presumably as a result of concomitant degradation of larger particles during the pelleting process.…”