Association of sodium butyrate and phytase on the performance, bone quality and intestinal development in broilers

This study assessed the effect of the combination of microencapsulated sodium butyrate (SB) and phytase (PH) on the performance, intestinal integrity, and bone development of broilers. The experiment comprised 736 chicks distributed in a completely randomised design in a 2 × 2 factorial scheme (with and without the inclusion of SB and with the inclusion of PH at the recommended dose and superdosing) totalling four treatments and eight repetitions of 23 birds each. SB was added at 0.750 kg/tonne and PH was included at 750 phytase units (FTU)/kg and 1 500 FTU/kg of diet. The live weight (LW), feed intake (FI) and feed conversion (FC) were evaluated weekly. Bone measurements of the tibia and femur, densitometry, length, the Seedor index, and diameter were performed at seven and 28 days. In the same ages, fragments of the jejunum and ileum segments were collected and subjected to a morphometry analysis. At seven days of age, the birds supplemented with the phytase superdosing showed a better FI and LW, and the microencapsulated SB in the diet showed a better LW and FC. In the period from one to 28 days, the treatment supplemented with SB provided a higher FI and LW. The SB supplementation resulted in greater bone measurements at seven and 28 days. The use of the superdosing phytase increased the villus length and width of the jejunum at seven days and at 28 days. There was an increase in the villus length, villus-to-crypt ratio, absorption area, and muscular layer of the jejunum and a decrease in the crypt width of the jejunum. The SB supplementation increased the ileum crypt width at seven days and there was no effect on any intestinal segment at 28 days. The supplementation of SB or PH 1 500 FTU/kg in the broiler diets' growth promoter or antibiotic-free resulted in a better performance and bone measurements, while the association of the additional PH 1 500 FTU/kg and SB supplementation resulted in the greater depth and width of the jejunum crypt and villus : ileum crypt at seven days and greater villus length and ileum absorption area at 28 days. The association of SB and PH may be a strategy to improve the performance and bone quality and intestinal integrity in broilers.