Calcium anacardate and citric acid as growth promoters for weaned piglets

•Dietary supplementation of Ca anacardate and citric acid improved the growth performance of nursery piglets.•Dietary supplementation of Ca anacardate and citric acid did not affect the diarrhea incidence of nursery piglets.•Dietary supplementation of Ca anacardate and citric acid improved the intestinal morphometry of weaned piglets. The objective of this study was to evaluate the effects of dietary supplementation of Ca anacardate and citric acid for weaned piglets on growth performance, diarrhea incidence, pH of gastrointestinal contents, blood profile, intestinal morphometry, and immunohistochemistry in the periods I (d 0 to 12), II (d 12 to 22), III (d 22 to 42), and total (d 0 to 42). A total of 96 barrows weaned at 21 d of age (5.96 ±0.81 kg) were allocated to 4 treatments with 8 replicates pens and 3 piglets per pen in a randomized block design. The experimental treatments were: positive control, diet with addition of antibiotic growth promoter (AGP, 0.05% zinc bacitracin); negative control, diet without addition of AGP; negative control diet with addition of 1% citric acid and 0.6% Ca anacardate; and negative control diet with addition of 1% citric acid and 1% Ca anacardate. Piglets fed the diets containing AGP or Ca anacardate and citric acid had decreased values of feed:gain during the period III and total period (P