PSVI-16 - Supplementing post-weaning diets with zinc and fiber: impact on performance and piglet health

Abstract: In pig production, weaning is a critical period where piglets face several environmental stressors. This transition leads to a significant growth reduction and can result in digestive disorders, including diarrhea. This project aimed to evaluate the impact of two sources of zinc and copper, as well as insoluble fiber, on the growth, intestinal health, and microbiota of weaned piglets. At weaning (21d of age), 180 piglets were allotted into 36 pens, with 5 piglets per pen, and fed according to a 2 × 3 factorial design that included insoluble fiber (lignocellulose source, 3% kg feed) and zinc/copper supplements. The zinc/copper supplements diets were composed as follows: Control: standard zinc oxide and copper sulfate (150 mg/kg each); Zn150: potentiated zinc oxide and monovalent copper (150 mg/kg each, Animine, France); Zn300: potentiated zinc oxide (300 mg/kg) and monovalent copper (150 mg/kg). The experimental diets were provided for 14 days (phase 1) post-weaning. Subsequently, all piglets received the same diets for phase 2 (14–28 days) and phase 3 (28–42 days). Piglets were weighed at weaning and on days 14, 28, and 42. At day 14, feces and blood samples were collected for microbiota analysis and gut health markers. During phase 1, fiber tended to reduce average daily gain (ADG; P = 0.085), while. average daily feed intake (ADFI) tended to be higher for Zn300 (P = 0.063) during phase 2. In the overall period ADG was higher for Zn300 (P = 0.038). A separate analysis was then performed considering the treatment Zn300 versus control, with or without fiber. In the first 14 days, no differences on performance were observed. At d14, superoxide dismutase (SOD) activity was influenced by the interaction between zinc and fiber, with higher activity observed in piglets receiving Zn300 without fiber in the diet (P = 0.047). Similarly, citrulline showed a tendency to be affected by the interaction between zinc and fiber (P = 0.061) with lower levels observed in Zn300 with fiber, suggesting a reduction of metabolic disorders. This is in line with overall performance from d1 to d42, where Zn300 improved ADFI (P = 0.031) regardless of fiber inclusion. Although the lack of significant difference on final BW, when fiber was not included, piglets fed potentiated Zn300 had 2 kg more than those fed control diet. The Shannon index of microbiota tended to be affected by fiber (P = 0.09). Supplementation of post weaning diets with potentiated zinc and monovalent copper at 300 mg/kg and 150 mg/kg, respectively, improved piglet growth during the post-weaning period, with some effects on inflammatory markers but reduced impact on fecal microbiota.