Emulsifier and enzymatic complex in diet for free range broiler chicken in the western amazon

Abstract

This study aimed to evaluate the effects of adding levels of emulsifier based on soy lecithin and enzymatic complex (xylanase, β-glucanase, galactosidase, protease, amylase, and β-mannanase) on the basal diet during the raising of free-range broiler chickens. The experimental design was completely randomized, with five treatments and six replications. Treatments were: T1: control diet, without enzymatic complex and emulsifier; T2: 0.2 kg t⁻¹ of enzymatic complex; T3: 0.5 kg t⁻¹ of emulsifier; T4: 0.2 kg t⁻¹ of enzymatic complex + 0.5 kg t⁻¹ of emulsifier; and T5: 0.3 kg t⁻¹ of enzymatic complex + 1 kg t⁻¹ of emulsifier. Performance data were collected every 14 days, and the animals were euthanized at 70 days to obtain carcass, breast, drumstick, and thigh yield and intestine collection for pH analysis and morphometry. The periods from 1 to 56 and 1 to 70 days showed a difference (P<0.05) in the parameters of zootechnical performance, the feed intake was lower in T4 and T5, and weight gain was better in T1, T2, T3, and T4. Feed conversion was better in T1, T2, and T4. No difference (P>0.05) was observed for poultry livability, carcass yield, viscera, and pH of duodenum and cecum. A difference was found for intestinal morphometry (P<0.05), and T5 showed the best villus/crypt ratio. The level with 0.3 kg t⁻¹ of enzymatic complex and 1 kg t⁻¹ of emulsifier indicated a better relationship between villi and crypts. However, the level with 0.2 kg t⁻¹ of enzymatic complex and 0.5 kg t−1 of emulsifier added to the commercial diet led to benefits such as decreased feed intake, without affecting weight gain, thus inducing a good feed conversion.
Keywords: Additives; Performance; Intestinal morphometry; Carcass yield.