Effect of a Laminarin Rich Macroalgal Extract on the Caecal and Colonic Microbiota in the Post-Weaned Pig

Abstract

Dietary supplementation with 300 ppm of a laminarin rich macroalgal extract reduces post-weaning intestinal dysfunction in pigs. A comprehensive analysis of the impact of laminarin on the intestinal microbiome during this period is essential to inform on the mode of action of this bioactivity. The objective of this study was to evaluate the effects of supplementing the diet of newly weaned pigs with 300 ppm of a laminarin rich extract, on animal performance, volatile fatty acids, and the intestinal microbiota using 16S rRNA gene sequencing. Pigs fed the laminarin-supplemented diet had higher average daily feed intake, growth rate, and body weight compared to pigs fed the control diet (p < 0.05). Pigs fed the laminarin-supplemented diet had reduced abundance of OTUs assigned to Enterobacteriaceae and increased abundance of OTUs assigned to the genus Prevotella (p < 0.05) compared to pigs fed the control diet. Enterobacteriaceae had negative relationships (p < 0.05) with average daily feed intake (ADFI), average daily gain (ADG), and butyric acid concentrations. In contrast, Prevotellaceae were positively correlated (p < 0.05) with ADFI, ADG, total VFA, acetic, propionic, butyric acids, and negatively correlated with isovaleric acid. Hence supplementation with a laminarin enriched extract potentially improves performance during the post-weaning period by promoting the proliferation of bacterial taxa such as Prevotella that favourably enhance nutrient digestion while reducing the load of potentially pathogenic bacterial taxa including Enterobacteriaceae.

Effects of reducing dietary crude protein concentration and supplementation with laminarin or zinc oxide on the faecal scores and colonic microbiota in newly weaned pigs

“…These differing responses suggest that factors such as weaning weight, diet composition, sanitary and husbandry conditions, and the duration of supplementation prior to sampling may influence the outcome of laminarin supplementation. As the composition of the laminarin-rich extract used in this study was similar to that used in previous research by our laboratory group (Rattigan et al, 2020;Vigors et al, 2020), it is possible that variation in the structural properties of the laminarin is also a factor contributing to the inconsistencies in the response to laminarin supplementation. Differences may include the molecular weight, the ratio of (1,3) to (1,6) glycosidic bonds or the structure and ratio of the two types of polymeric chains M-type (terminate with mannitol) and G-type (terminate with glucose; Zargarzadeh, Amaral, Custodio, & Mano, 2020).…”

“…It was anticipated that laminarin supplementation would increase beneficial microbial populations, reduce Enterobacteriaceae and increase butyrate concentrations based on the observations of Rattigan et al (2020) and Vigors et al (2020). However, the results indicate that supplementation with laminarin for 9 days in healthy pigs with normal FS does not confer any additional benefits on the microbiota or on performance which was comparable to that of ZnO-supplemented pigs.…”

The Pros and Cons of Using Algal Polysaccharides as Prebiotics

“…This was accompanied by a lower count of potentially pathogen strains of attaching and effacing Escherichia coli (AEEC) while Lactobacillus and Enterobacteriaceae were not affected ( 72 ). The third study used 16S rRNA gene sequencing to evaluate the microbiota after laminaran supplementation ( 73 ). Compared to control animals, the supplemented pigs had lower abundances of Enterobacteriaceae and higher abundance of Prevotella , with more production of acetate and butyrate.…”

Evaluation of the in vitro effects of the increasing inclusion levels of yeast β-glucan, a casein hydrolysate and its 5 kDa retentate on selected bacterial populations and strains commonly found in the gastrointestinal tract of pigs

“…This is probably linked with the reduction of certain members of the microbiota due to YBG supplementation. Prevotella genus, for instance, has previously been correlated with increased butyrate production, 61 most likely via bacterial cross-feeding interactions.…”