Effect of Processing on Feed Quality and Bio-Economic Performances of Broiler Chickens in Benin

Abstract

The purpose of this study was to compare the quality of feeds and the performances of broilers fed with diets processed by six processing methods. Unsexed 450 day-old chickens (Red Bro) were fed up to 49 days of age with a pelleted and five mashed feeds. The feeds were processed in factories using hammer grinders or cereal mill and different types of mixer (small versus big, vertical versus oblique, manual). Dry sieving and chemical analyses of feeds were done using samples from three bathes (top, middle and bottom) defined during the collection of the feed from the mixers. The physical and chemical uniformity of the feeds did not vary with the batches (P>0.05). The contents of ash, crude protein, gross and metabolizable energy were similar between feeds. However, crude fibre content was significantly higher (P = 0.03) in feeds processed in a company supplying mainly feeds for rabbits. About 91% of particles in pelleted feed had more than 4.75 mm, whereas 45 to 54% of particles in mashed feeds had less than 1 mm. The proportion of particles having 2.36–4.75 mm was significantly lower in the feed from cereal mill, while that of particles having 1–2.36 mm increased significantly with the capacity of the mixer. However, the geometric mean diameter (GMD), were similar between mashed feeds (1.12 – 1.21 mm) and significantly higher in pelleted feed (6.01 mm). In spite of the variations in particles size, the daily feed intake, the daily weight gain (WG), the feed conversion ratio and the economic feed efficiency were similar between diets indicating an adaptation of chickens to the particles size of the feeds to fulfill their requirements. However, at three week of age (d21), broilers fed with diets from the cereal mill and bigger mixers had significantly higher final body weight (FBW). At d49, the broilers fed grower pelleted feeds (HP) diet had a significantly higher FBW compared to those fed mashed diets (1812 g vs 1534 to 1607 g). Unfortunately, up to d21 the feeding cost was significantly higher in HP than mashed diets (0.794 vs 0.610 to 0.659 €/kg WG). On the whole, the pelleted feed was cost effective due to a high pelleting cost. The quality of pelleted feeds processed in Benin was more profitable for grower than starter chickens. The bioeconomic performances were similar between mashed feeds; but the bigger mixers appeared more suitable than the smaller for the processing of starter feeds of broilers.