The effects of supplementing the diet of the sow with seaweed extracts and fish oil on aspects of gastrointestinal health and performance of the weaned piglet

A 2 × 2 factorial study (n = 10 sows/treatment) was performed to investigate the effects of maternal dietary supplementation with seaweed extract (SWE) (yes vs. no) and fish oil (FO) inclusion (0 vs. 100 g/day) from day 109 of gestation until weaning (24 days) on piglet performance and intestinal microflora, intestinal morphology and inflammatory gene expression in 9 day old weaned piglets. There was an interaction between SWE and FO on E. coli populations (P < 0.05) in the caecum and villous height to crypt depth ratio in the ileum (P < 0.01). Piglets from SWE supplemented sows had lower E. coli populations in the caecum and increased villous height to crypt depth ratio in the ileum compared to the basal diet (P < 0.05). However, there was no effect of SWE on E. coli populations and villous height to crypt depth ratio with FO inclusion. The mRNA expression of the pro-inflammatory cytokines (IL-1α and IL-6) was increased in the colon of FO supplemented piglets (P < 0.05) and SWE supplementation induced an increase in ileal TNF-α expression (P < 0.01). Piglets from SWE supplemented sows had improved daily gains (P < 0.05) post weaning while FO increased daily gain (P < 0.05) and gain to feed ratio (P < 0.01) from days 7–14. In conclusion, these results demonstrate the influence of the maternal diet on aspects of piglet gut health and post-weaning performance.