Does algae β-glucan affect the fecal bacteriome in dairy calves?

Abstract

β-glucans has been reported to be associated with many health-promoting and improvements in animal performance, however, information about their effects on the bacterial community remains unknown. This study aimed to investigate how the addition of β-glucans can affect the fecal bacterial community with possible consequences on animal growth and health. For this, newborn Holstein calves (n = 14) were individually housed in tropical shelters and blocked according to sex, date, and weight at birth and randomly assigned to one of the following treatments: (1) Control: milk replacer (14% solids, 24% CP, 18.5% fat); (2) β-glucans: milk replacer supplemented with β-glucans (2 g/d). All calves were bucket fed 6 L/d of milk replacer and received water and starter concentrate ad libitum starting on d 2. To evaluate the bacteriome, fecal samples were collected at weeks 1, 2, 4, and 8. The bacterial community was assessed through sequencing of the V3-V4 region of the 16S rRNA gene on the Illumina MiSeq platform and analyzed using the DADA2 pipeline. No differences for Shannon and Chao1 indexes were observed for treatments, but both indexes increased with age (P < 0.001). There were dissimilarities in the structure of the bacterial community during the pre-weaning period (P = 0.01). In a deeper taxonomic level, Collinsella (Actinobacteriota), Prevotella (Bacteroidota), and Lactobacillus (Firmicutes) were the most abundant genera (9.84, 9.54, and 8.82% of the sequences, respectively). β-glucans promoted a higher abundance of Alloprevotella and Holdemanella, which may indicate a beneficial effect of supplementation on dairy calves. The bacterial community was highly correlated with the fecal score at weeks 1 and 2 and with starter concentrate intake at week 8. In conclusion, algae β-glucan supplementation could be beneficial to fecal bacteriome and consequently to the health and performance of dairy calves.

Effect of β-1,3/1,6-glucan on gut microbiota of yellow-feathered broilers

“…Bacteroides encodes polysaccharide binding proteins in the outer membrane through polysaccharide utilization sites (PUL) to capture polysaccharides and decompose polysaccharides into oligosaccharides to promote the utilization and uptake of dietary polysaccharides by Bacteroides (Tamura et al 2017 ). Faecalibacterium facilitates the utilization of acetate in the intestine (Virginio Junior et al 2021 ). Acetate is used as an energy source for the liver and peripheral tissues and as a signal molecule in gluconeogenesis and lipogenesis (Zambell et al 2003 ).…”

“…β-glucan is considered a natural prebiotic with various biological functions, such as antioxidant, free radical scavenging, anti-tumor, anti-cancer, and immune activation, competing with pathogenic microorganisms for binding sites in intestinal epithelial cells to prevent inflammation (Baldassano et al 2017 ; De Marco et al 2021 ; Mo et al 2017 ; Virginio et al 2021 ; Xu et al 2009 ). The main chain of β-1,3/1,6-glucan is a linear skeleton with β-1,3 bonds, and the side chain is a highly branched β-1,6 bond (Baldassano et al 2017 ).…”

“…Jayachandran et al reported that the gut microbiota might realize the immunomodulatory effect of β-glucan as the mediator of the immune response (Jayachandran et al 2018 ). At present, the research on β-glucan and gut microbiota mainly include rats (Aoe et al 2019 ), mice (Shi et al 2020 ), fish (Harris et al 2020 ), dogs (Van et al 2020 ), weaned piglets (Metzler-Zebeli et al 2011 ), and calves (Virginio et al 2021 ), which have not been reported in broilers. Among them, β-glucan distinctly raised the number of Lactobacilli and Bifidobacteria in the colon of weaned pigs, and also increased the concentration of butyrate in the stomach, cecum and colon, which may be beneficial to the intestinal development of weaned pigs (Metzler-Zebeli et al 2011 ).…”

Beta-Glucan Alters Gut Microbiota and Plasma Metabolites in Pre-Weaning Dairy Calves

“…Ma et al [ 16 ] found that dietary supplementation of 75 mg/kg β-glucan increased average daily gain (ADG) and gain-to-feed ratios in calves during the milk-feeding period. Studies have reported that milk replacer supplemented with 2g of β-glucan per day are beneficial to health and growth in preweaning calve, increasing the abundance of Alloprevotella and Holdemanella in gut [ 17 ]. However, the relationship of gut microbiota-host metabolism and β-glucan supplementation in pre-weaning dairy calves remains unclear.…”

Effect of supplementation with algae β-glucans on performance, health, and blood metabolites of Holstein dairy calves

“…There are 2 common sources of bioavailable β-glucans: one is algae such as Euglena gracilis; these algae were shown to have highly water soluble portions in an in vitro study (Phillips et al, 2019). Recently, supplementation of algae β-glucans to calves promoted greater abundance of the Alloprevotella and Holdemanella genera in feces, suggesting that feeding algae β-glucans to calves may positively alter the ratio of commensal bacteria in the lower gut (Virginio Junior et al, 2021). However, to our knowledge, no study has investigated the effect of algae-derived β-glucans on calf health and performance, and this warrants investigation.…”