Effect of different doses of coated butyric acid on growth performance and energy utilization in broilers.

We recently applied four dietary treatments in experiments I and II to determine the effect of protected calcium butyrate (BP) on growth performance and nutrient digestibility in broiler chickens. A group of one-day-old male Ross 308 broiler chicks (total 960, 480 per trial) were used in the study. In experiment I, the basal diets were fed with protected BP inclusion (0.2, 0.3, or 0.4 g/kg of finished feed) (BP) or without (C). In experiment II, 4 different diets were tested: 1) basal diet with no supplementation (C), 2) basal diet supplemented with protected BP (0.3 g/kg) (BP), 3) basal diet supplemented with avilamycin (6 mg/kg, active substance) a common antibiotic growth promoter (AGP) (Av), and 4) basal diet supplemented with the combination of both avilaymicin and BP. In experiment I, considering the entire study period, the use of BP improved feed conversion ratio (P<0.05) irrespective of the dose. Apparent total tract crude fat digestibility and apparent metabolizable energy corrected for nitrogen (AMEN) were improved after BP supplementation (P<0.05). In experiment II, A or AB diets improved (P<0.05) body weight gain compared to the control treatment. The diets Av, BP, and AvB improved (P<0.05) feed conversion ratio compared to the control treatment. Birds from the treatment diet were characterized by having the thickest mucosa (P<0.05). On days 14, 35, and 42, the use of AB diets improved AMENcontent compared to the control treatment (P<0.05). The apparent ileal digestibility of amino acid data showed that Av or AvB treated birds were characterized by higher Asp, Glu, Cys, Gly, and Ala ileal digestibility than the control animals (P<0.05). The use of Av, BP, or AvB increased ileal digestibility of Thr, Ser, and Pro (P<0.05). There is an indication that BP, alone or in combination with avilamycin, improve the digestion and absorptive processes and consequently birds performance results.