Performance and gut permeability of post-weaned piglets are influenced by different sources of lignocellulose fiber

•Eubiotic lignocellulose fiber supplementation tends to improve overall performance of piglets.•Eubiotic lignocellulose fiber can be beneficial to improve gut integrity.•Eubiotic lignocellulose fiber provided less fecal excretion of Zn in the environment.•The use of eubiotic lignocellulose fiber allows a reduction of ZnO as an infeed antimicrobial. Antibiotics and ZnO as antimicrobial agents in post-weaning diets can improve growth performance of nursery piglets. However, this practice can lead to antibiotic resistance and contribute to zinc pollution to the environment. Therefore, the aim of this study was to evaluate the effect of replacing AGP (antibiotic as growth promotor) with a lignocellulose or an eubiotic lignocellulose associated with different inclusion rates of ZnO in post-weaning diets on the piglet's growth performance, intestinal permeability, diarrhea score, Escherichia coli excretion and concentration, Zn and Cu fecal excretion. A total of 90 piglets weaned at 25 d of age (7.84 ± 1.71 kg) were distributed in a randomized block design and were assigned to 5 treatments: a commercial control diet, T1 (tiamulin as AGP with high dose of ZnO); T2 (lignocellulose with high dose of ZnO); T3 (eubiotic lignocellulose with high dose of ZnO); T4 (lignocellulose with low dose of ZnO); T5 (eubiotic lignocellulose with low dose of ZnO), with 6 replicates and 3 piglets per pen. The nutritional program was divided into 4 phases (phase 1: 25 to 32 d; phase 2: 33 to 39 d; phase 3: 40 to 53 d; phase 4: 54 to 67 d). The overall nursery voluntary feed intake was affected by the treatments (P < 0.001), whereas T5 and T1 showed the highest intakes followed by T2, T4, T3. Still, the treatments did not influence the final weight of the piglets. There were differences (P < 0.05) between the phases for the sugar absorption test (SAT). The observed SAT values in the second phase (60 d of age) were lower compared to the first phase (1 wk post-weaning). In addition, pigs fed low doses of ZnO in the diets showed lower (P < 0.05) fecal Zn and Cu excretions. In conclusion, the use of eubiotic lignocellulose fiber in the diets for piglets in the nursery phase can be a viable strategy to allow the withdrawal of tiamulin as an AGP and reduce the use of dietary ZnO without affecting negatively on the growth performance of the piglets, as well as reducing the fecal excretion into the environment. Nevertheless, one must consider the possibility that there will be an increased us