PSIII-15 - Weaning strategies in swine: Assessing the combined effects of zinc oxide supplementation and stall vs. traditional weaning methods on post-weaning outcomes

Abstract: Morbidity and mortality rates among weaned piglets have become increasingly concerning, particularly due to infections caused by Enterotoxigenic Escherichia coli. As regulations on antibiotic use in livestock tighten and concerns about antimicrobial resistance rise, there is an urgent need for alternative strategies to enhance the health of weaned piglets. Dietary and environmental approaches, like zinc oxide supplementation and varied housing methods, may provide solutions. This study aimed to assess the combined effects of zinc oxide supplementation and stall weaning compared to traditional weaning methods on post-weaning outcomes. The study involved 326 piglets from 23 litters (initial BW: 5.4 ± 0.2 kg), weaned at 19 ± 2 days and housed by litter (14 ± 2 pigs per pen). Twelve litters remained in STALLS, while 11 were moved to nursery PENS. Pigs were assigned to a control diet or supplemented with 2000 ppm zinc oxide, resulting in four treatment groups: STALLS with no zinc oxide (SxC), STALLS with 2000ppm zinc oxide (SxZ), PENS with no zinc oxide (PxC), and PENS with 2000 ppm zinc oxide (PxZ). Body weight (BW) and feed consumption were measured on days 0, 7, and 14 to calculate average daily gain (ADG), average daily feed intake (ADFI), and gain to feed ratio (G: F). Blood and fecal samples were collected from three pigs per litter on days 0 and 14 to analyze IgG, serum antibodies (PCV2), and fecal microbiome changes (analysis pending). Data were analyzed using the PROC MIXED procedure in SAS to test the fixed effects of treatment, housing, and their interaction on growth performance. On day 7 post-weaning, both STALL treatments had higher BW than the PEN treatments: SxC (6.1 kg) and SxZ (6.1 kg) Vs. PxC (5.1 kg) and PxZ (5.2 kg) (P < 0.001). On day 14, the SxZ treatment had greater BW (8.2 kg) than all other treatments (SxC: 7.6 kg; PxC: 7.1 kg; PxZ: 8 kg) (P = 0.04). Average daily feed intake tended to be greater in SxZ pigs (267 g/d) compared to SxC pigs (226 g/d) (P = 0.078), while no differences were observed between the PEN treatments (PxC: 237 g/d; PxZ: 253 g/d). In conclusion, stall weaning and zinc oxide supplementation can enhance post-weaning performance in piglets, leading to improved feed intake and growth. These strategies may help pig producers boost piglet health and overall productivity.