Protective effect of phytogenic plus short and medium-chain fatty acids-based additives in enterotoxigenic Escherichia coli challenged piglets

Abstract

Post Weaning Diarrhea (PWD) is the most important multifactorial gastroenteric disease of the weaning in pig livestock. Phytogenic (PHY) natural extracts are largely studied as alternatives to antibiotic treatments in combating the global concern of the antimicrobial resistance. The aim of this study was to evaluate the protective effect of innovative phytogenic premix with or without short and medium chain fatty acids (SCFA and MCFA) in O138 Escherichia coli challenged piglets. Twenty-seven weaned piglets were allotted into four groups fed different diets according to the following dietary treatments: CTRL (n = 13) group fed basal diet, PHY1 (n = 7) fed the basal diet supplemented with 0.2% of phytogenic premix, PHY2 (n = 7) fed the basal diet supplemented with 0.2% of phytogenic premix added with 2000 ppm of SCFA and MCFA. After 6 days of experimental diet feeding, animals were challenged (day 0) with 2 × 109 CFU of E. coli and CTRL group was divided at day 0 into positive (challenged CTRL + ; n = 6) and negative control group (unchallenged CTRL-; n = 7). Body weights were recorded at -14, -6, 0, 4 and 7 days and the feed intake was recorded daily. E. coli shedding was monitored for 4 days post-challenge by plate counting. Fecal consistency was registered daily by a four-point scale (0–3; diarrhea > 1) during the post-challenge period. Tissue samples were obtained for gene expression and histological evaluations at day 7 from four animals per group. Lower average feed intake was observed in CTRL + compared to PHY2 and CTRL during the post-challenge period. Infected groups showed higher E. coli shedding compared to CTRL- during the 4 days post-challenge (p < 0.01). PHY2 showed lower frequency of diarrhea compared to PHY1 and CTRL + from 5 to 7 days post-challenge. No significant alterations among groups were observed in histopathological evaluation. Duodenum expression of occludin tended to be lower in challenged groups compared to CTRL- at 7 days post-challenge (p = 0.066). In conclusion, dietary supplementation of PHY plus SCFA and MCFA revealed encouraging results for diarrhea prevention and growth performance in weaned piglets.

Beneficial Effects of Phytogenic Feed Additives on Epithelial Barrier Integrity in an In Vitro Co-Culture Model of the Piglet Gut

“…Similar to acetylsalicylate compounds and products (“aspirin”), anti-inflammatory properties have been reported for methyl esters of salicylic acid and glycosides thereof [ 64 ]. Both PFAs also feature further plant-based additives and their active components with additional reported beneficial properties, e.g., a complex plant powder mix, including cinnamon bark, and its active component cinnamaldehyde [ 5 , 7 , 11 , 21 , 24 , 65 ], gentian root, grape seed and skin extract [ 66 , 67 ], and angelica root. Licorice extract, included only in D-DC2, has also been reported as a feed additive with various beneficial properties, e.g., on performance, intestinal health, and the immune system [ 12 , 68 ].…”

“…PFAs are subject to various in vivo and in vitro studies across species, shedding light on diverse areas of potential activity [ 5 , 6 , 7 , 11 , 12 , 21 ] such as immunological status and inflammation [ 16 , 21 , 22 , 23 , 24 , 25 ], gastrointestinal health and barrier integrity [ 16 , 22 , 23 , 24 , 25 , 26 , 27 ], protective effects against pathogens and toxins of various kinds [ 23 , 24 , 25 , 27 ], as well as overall animal growth and performance [ 15 , 21 , 24 , 26 , 27 ]. In general, suitable in vitro models are of significant importance and many available in vitro studies assess specific subprocesses of gut functionality and interactions.…”

Impacts of F18+ Escherichia coli on Intestinal Health of Nursery Pigs and Dietary Interventions

“…Multiple research investigations have linked F18 + E. coli to PWD and reduced growth performance [7,16,[66][67][68]76,77,79,81,83,[85][86][87][88]. These studies on nursery pigs challenged with F18 + E. coli showed an average reduction of 27% in ADG, 10% in ADFI, and 20% in feed efficiency (Figure 4A-C).…”

“…Moita et al [129] reported that a blend of castor oil and cashew nutshell liquid improved the microbiota composition by increasing the abundance of Lactobacillus and Pseudomonas, while reducing the abundance of Helicobacter and Campylobacter. According to Caprarulo et al [88], the use of a blend of phytobiotics was effective in reducing the effects caused by F18 + E. coli on the growth performance by increasing G:F (51%) and health of nursery pigs by inhibiting the proliferation of pathogens and increasing the abundance of beneficial bacteria. Chang et al [85] reported that a mixture of thymol, carvacrol, and bitter citrus extract improved immune responses by reducing TNF-α (23%), IL6 (21%), and intestinal integrity resulting in an increased ADG (49%) in nursery pigs challenged with F18 + E. coli.…”

Acetate and propionate effects in response to LPS in a porcine intestinal co-culture model

“…Fatty acids have been considered an alternative to antibiotics or zinc oxide [ 4 ] as they stimulate immunity by triggering local proliferation and the adaptive immune response [ 5 ], particularly against Salmonella enteritidis and enteropathogenic Escherichia coli [ 6 , 7 ]. SCFA are pivotal as a fuel for intestinal epithelial cells and as antibacterial agents, inducing cell lysis and inhibition of enzyme activity [ 8 ], as well as stimulating gastrointestinal motility [ 9 ].…”