Effect of benzoic acid, sodium butyrate and sodium butyrate coated with benzoic acid on growth performance, digestibility, intestinal morphology and meat quality in grower-finisher pigs

Abstract

Organic acids and their salts have the potential to promote growth in weaner and grower-finisher pigs. The aim of this project was to evaluate the effects of benzoic acid, sodium butyrate and sodium butyrate coated with benzoic acid on the growth performance, total tract energy digestibility, gut morphology and meat quality in grower-finisher pigs between 30 and 90 kg live weight. Sixty-four Duroc x (Large White x Landrace) pigs were balanced for live weight within sex and allocated to 4 dietary treatment groups (8 males and 8 females per group): control diet (C), C + benzoic acid (4.95 g/kg diet), C + sodium butyrate (1.47 g/ kg diet) and C + sodium butyrate (0.9 g/kg diet) coated with benzoic acid (2.1 g/kg diet). There was no significant difference between sexes or between dietary treatments for the organic or energy digestibility or the histological measurements: mucosal depth, villi length, crypt depth, number of goblet cells in villi, and number of goblet cells in crypt. Male pigs had a higher daily feed intake (P<0.05) and higher average daily gain (P<0.05), a lower feed conversion ratio (P<0.05), were heavier at slaughter (P<0.05) and consequently had a higher carcass weight (P<0.05) than female pigs. The ultimate pH was higher for male pigs than female pigs. No statistically significant differences (P>0.05) were found between the diets for any of the growth performances or meat quality parameters. However, when butyrate was added to the diet, L* values (P = 0.052) and percentage (%) drip losses after 24 h tended to be higher (P = 0.053). The supplementation of benzoic acid, sodium butyrate or sodium butyrate coated with benzoic acid in the diet, had no significant effect on growth performance, meat quality, digestibility or gut morphology in grower-finisher pigs kept under nutritional and environmental low-stress conditions.