Effect of dietary fiber fermentation on short-chain fatty acid production and microbial composition in vitro.

BACKGROUND: The efficient utilization of fiber-rich co-products is important for optimizing feed resource utilization and animal health. This study was conducted to evaluate the fermentation characteristics of fiber-rich co-products, which had equal quantities of total dietary fiber (TDF), at different time points using batch in vitro methods. It considered their gas production, short-chain fatty acid (SCFA) production, and microbial composition. RESULTS: The fermentation of wheat bran (WB) and oat bran (OB) showed higher and faster (P < 0.05) gas and SCFA production than corn bran (CB), sugar beet pulp (SBP), and soybean hulls (SH). The α-diversity was higher in the CB, SBP, and SH groups than in the WB and OB groups (P < 0.05). At the phylum level, OB and WB fermentation showed lower (P < 0.05) relative abundance of Actinobacteria than the CB, SBP, and SH groups. At the genus level, OB and WB fermentation increased the Enterococcus population in comparison with the CB, SBP, and SH groups, whereas CB and SBP fermentation improved the relative abundance of the Christensenellaceae R-7 group more than the WB, OB, and SH groups (P < 0.05). CONCLUSION: Overall, WB and OB were rapidly fermented by fecal microbiota, in contrast with SBP, SH, and CB. Fermentation of different fiber-rich co-products with an equal TDF content gives different responses in terms of microbial composition and SCFA production due to variations in their physicochemical properties and molecular structure. © 2020 Society of Chemical Industry.

Maternal Fish Oil Supplementation Affects the Social Behavior, Brain Fatty Acid Profile, and Sickness Response of Piglets.

BACKGROUND: Maternal dietary docosahexaenoic acid (DHA) intake is thought to affect development in the offspring. OBJECTIVE: We assessed the impact of maternal dietary DHA on behavior, brain fatty acid (FA) profile, and sickness response of offspring in pigs, a pertinent model for human nutrition. METHODS: Sows (n = 24) were fed a diet with DHA-rich fish oil (FO) (20 g/kg) or high-oleic acid sunflower oil (HOSF) (20 g/kg) from day 61 of gestation through lactation. At 4 wk of age, 4 piglets per litter were weaned and mixed with piglets from other litters. Behavior was observed in 4- to 8-wk-old piglets, and brain FA composition was analyzed at 4 (n = 15) and 14 (n = 12) wk. Thirteen-week-old piglets (n = 48) were subjected to a lipopolysaccharide (LPS) challenge. Body temperature, plasma cytokines, and motivation to approach a familiar human, indicative of a sickness response, were measured. RESULTS: FO-fed pigs displayed more social activities (+262%, P = 0.02), played more (+61%, P = 0.03), and tended to show fewer oral manipulative behaviors directed at pen mates (-25%, P = 0.06) than did HOSF-fed pigs up to 4 wk after weaning. Brain DHA concentrations were higher in FO- than in HOSF-fed pigs up to 10 wk after supplementation (+10-50%, P < 0.001), although differences declined with age. Body temperature (P < 0.001) and tumor necrosis factor α and interferon Î³ concentrations (P < 0.05) increased after LPS injection, but no diet effect was found (P > 0.10). LPS-treated pigs were less likely to approach the human than saline-treated pigs in the HOSF-fed (-29%, P = 0.0003), but not in the FO-fed group (-13%, P = 0.11). CONCLUSIONS: Maternal DHA beneficially affected offspring social behavior after weaning and mildly attenuated sickness behavior after an inflammatory challenge in pigs. These behavioral changes may be mediated by increased brain DHA proportions.