Administration of potentiated Zn and monovalent Cu in weanling piglets diet

The aim of this study was to determine the suitability of potentiated Zn combined with a monovalent Cu as a replacement for pharmacological ZnO supplementation in piglets after weaning. A total of 120 piglets (7.143 ± 0.924 kg) were weaned at 27d and divided into 4 experimental treatments. A positive control (PC, 2500 ppm of Zinc through standard ZnO) was compared to 3 treatments in which Cu and Zn were supplemented through potentiated Zn (HiZox®) and monovalent Cu (CoRouge®) at European and non-European levels of inclusion: EU (120 ppm of Zn; 140 ppm of Cu), non-EU+ (300 ppm of Zn; 200 ppm of Cu) and non-EU- (300 ppm of Zn; 140 ppm of Cu). Performance data were analyzed using the MIXED procedure of SAS. Serum diamine oxidase (DAO) and D-lactate were analysed through a MIXED procedure of SAS at 0d and 14d. SIgA was evaluated with a GLM procedure of SAS (28d). Fecal samples (14d and 28d) and intestinal content (28d) were collected and the V3–V4 hypervariable regions of the bacterial 16S gene were sequenced in one MiSeq (Illumina) run. Performances were not affected by different Zn and Cu dosages. Plasma DAO was negatively (p<0.05) affected in non-EU- treatment. The level of sIgA was increased in PC group (157.73 ± 19.58 ng/ml) compared to EU (143.81 ± 12.96 ng/ml; p<0.05) and non-EU- group (138.01 ± 16.88 ng/ml; p<0.01). non-EU- contributed to a significant decrease in biodiversity in fecal microbiota as shown by the Shannon diversity and Simpson evenness indexes (p<0.05). A total of 18 differentially abundant genera (p<0.05) were identified in the caecal content with the presence of genera linked to the disruption of the gut barrier (Campylobacter) with non-EU- . These results suggest that a more balanced supplementation of the two trace elements, through more bioavailable sources, could represent a valid tool to enhance gut health of weaning piglets and reduce environmental impact.