Bacillus Amyloliquefaciens-9 as an Alternative Approach to Cure Diarrhea in Saanen Kids

Combining 16S rRNA Sequencing and Metabolomics Data to Decipher the Interactions between Gut Microbiota, Host Immunity, and Metabolites in Diarrheic Young Small Ruminants

Diarrhea is associated with gut microbiota, immunity, and metabolic alterations in goat kids and lambs. This study used 28 lambs (11 healthy and 17 diarrheic) and 20 goat kids (10 healthy and 10 diarrheic) to investigate the association between diarrhea occurrence and changes in gut microbiota, metabolism, and immunity in goat kids and lambs. The results revealed that Firmicutes, Proteobacteria, and Bacteroidetes were the dominant phyla in goat kids and lambs. In addition, Enterobacteriaceae and Lachnospiraceae families were identified in both diarrheic goat kids and lambs. Furthermore, functional prediction of microbiota showed that it was involved in cell motility and cancer pathways. The identified differential metabolites were implicated in the bile secretion pathway. Lambs had significant differences in immunoglobulin G (IgG), immunoglobulin M (IgM), interleukin-1β (IL-1β), and tumor necrosis factor-alpha (TNF-α) compared to goat kids. IgG and IL-1β were positively correlated to Patescibacteria, Clostridiaceae, and unclassified_Muribaculaceae in both diarrheic goat kids and lambs. In addition, weighted gene co-expression network analysis (WGCNA) revealed that the MEgreen module was positively associated with IgG, IgM, IL-1β, TNF-α, and triglyceride (TG). In conclusion, our results characterized the gut microbiota, metabolism, and immune status of lambs and goat kids suffering from diarrhea.

Review: Feeding strategies for rearing replacement dairy goats - from birth to kidding

Goat kid rearing is a key profit driver and the cornerstone of future herd productivity in dairy systems. As goat kids get older, and progress from liquid (i.e., colostrum, milk) to solid feed (i.e., concentrate, hay, pasture), there is a reduction not only in feed cost but also in labour cost, disease susceptibility and mortality rates. Hence, research on rearing dairy goats has traditionally focused on improving early neonatal performance. However, recent research reveals that early-life nutrition may have long-term effects, and consequently, impact the lifetime productive performance and health of dairy goats. Therefore, this literature review has collected research on the various aspects of rearing replacement dairy goat kids in different production systems. It summarises research on areas such as colostrum management (i.e., colostrum quality, time, volume and frequency of colostrum feeding), liquid feeding in preweaned kids (i.e., maternal suckling vs artificial, restricted vs unrestricted), weaning strategies (i.e., abrupt vs step-down), and postweaning to postpubertal nutrition in replacement dairy goats, whilst highlighting gaps in the existing literature, and areas where it would be beneficial to refine and validate current recommendations. Such information can be used in the development of management plans to maximise the benefits of early-life nutrition on the long-term productivity of dairy goats.

Clinical implications of gut microbiota and cytokine responses in coronavirus disease prognosis

Objectives

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infects gut luminal cells through the angiotensin-converting enzyme-2 receptor and disrupts the gut microbiome. We investigated whether the gut microbiome in the early stage of SARS-CoV-2 infection was associated with the prognosis of coronavirus disease (COVID-19).

Methods

Thirty COVID-19 patients and 16 healthy controls were prospectively enrolled. Blood and stool samples and clinical details were collected on days 0 (enrollment), 7, 14, and 28. Participants were categorized into four groups by their clinical course.

Results

Gut microbiota composition varied during the clinical course of COVID-19 and was closely associated with cytokine levels (p=0.003). A high abundance of the genus Dialister (linear discriminant analysis [LDA] effect size: 3.97856, p=0.004), species Peptoniphilus lacrimalis (LDA effect size: 4.00551, p=0.020), and Anaerococcus prevotii (LDA effect size: 4.00885, p=0.007) was associated with a good prognosis. Starch, sucrose, and galactose metabolism was highly activated in the gut microbiota of the poor prognosis group. Glucose-lowering diets, including whole grains, were positively correlated with a good prognosis.

Conclusion

Gut microbiota may mediate the prognosis of COVID-19 by regulating cytokine responses and controlling glucose metabolism, which is implicated in the host immune response to SARS-CoV-2.

Rumen and fecal microbiota profiles associated with immunity of young and adult goats

Low immunity at birth increases risk of disease of young livestock, such as goat kids. Microbiomes change as animals mature, and a healthy microbiome is related to decreased risk of disease. The relationship between microbiota profiles and immunity at different developmental stages remains unclear. Young (female, n = 12, 30 d) and adult (female, n = 12, 2 yrs. old) Saanen dairy goats were used to investigate changes in rumen microbiomes, fecal microbiomes, and their correlations to circulating immune factors. Serum IgG (P = 0.02) and IgM (P < 0.01) were higher at 2 years than 30 d of age, but there were no differences in IgA (P = 0.34), IL-2 (P = 0.05), IL-4 (P = 0.37) and IL-6 (P = 0.73) between ages. Amplicon sequencing analysis revealed young goats had a higher diversity of bacterial communities in rumen and lower diversity in feces compared with adult goats. Ten genera in rumen and 14 genera in feces were positively correlated with serum IgM concentration across both ages. Olsenella, Methanosphaera, Quinella, Candidatus_Saccharimonas, and Methanobrevibacter in rumen and Ruminobacter, Treponema, Rikenelaceae_ RC9_ gut_ Group in feces were positively correlated with the concentration of IgG. The correlation analysis using weighted gene co-expression network analysis showed the MEblue module was positively associated with the IgG and IgM. These data provide novel insight into the association between rumen-feces microbiota and immune response. Further experiments are needed to investigate whether inoculating young livestock with immune-related bacteria identified can improve the immune status. Our data suggest a possible strategy to improve the immunity of the kids by alterative microbiota profiles.

Antimicrobial Bacillus: Metabolites and Their Mode of Action

The agricultural industry utilizes antibiotic growth promoters to promote livestock growth and health. However, the World Health Organization has raised concerns over the ongoing spread of antibiotic resistance transmission in the populace, leading to its subsequent ban in several countries, especially in the European Union. These restrictions have translated into an increase in pathogenic outbreaks in the agricultural industry, highlighting the need for an economically viable, non-toxic, and renewable alternative to antibiotics in livestock. Probiotics inhibit pathogen growth, promote a beneficial microbiota, regulate the immune response of its host, enhance feed conversion to nutrients, and form biofilms that block further infection. Commonly used lactic acid bacteria probiotics are vulnerable to the harsh conditions of the upper gastrointestinal system, leading to novel research using spore-forming bacteria from the genus Bacillus. However, the exact mechanisms behind Bacillus probiotics remain unexplored. This review tackles this issue, by reporting antimicrobial compounds produced from Bacillus strains, their proposed mechanisms of action, and any gaps in the mechanism studies of these compounds. Lastly, this paper explores omics approaches to clarify the mechanisms behind Bacillus probiotics.

Bacillus amyloliquefaciens-9 Reduces Somatic Cell Count and Modifies Fecal Microbiota in Lactating Goats

Subclinical mastitis is one of the major problems affecting dairy animals’ productivity and is classified based on milk somatic cell counts (SCC). Previous data showed that marine-derived Bacillus amyloliquefaciens-9 (GB-9) improved the immunity and the nonspecific immune defense system of the body. In this study, the potential role of GB-9 in improving subclinical mastitis was assessed with Radix Tetrastigmae (RT) as a positive control in subclinical mastitis Saanen dairy goats. The current data showed that GB-9 and RT significantly reduced the SCC in dairy goats. After being fed with GB-9 or RT, the decreased concentrations of malondialdehyde, IgA, IgM, IL-2, IL-4, and IL-6 were observed. The amplicon sequencing analysis of fecal samples revealed that GB-9 significantly altered the bacterial community. Bacteroides and Phascolarctobacterium were the major genera that respond to GB-9 feeding. The correlation analysis using weighted gene co-expression network analysis showed a MePink module was most associated with the serum concentrations of immunoglobulin and interleukin. The MePink module contained 89 OTUs. The feeding of GB-9 in decreasing the SCC was associated with the altered abundance of Bacteroides, which was correlated with the concentrations of immunoglobulins and chemokines. Collectively, the current data suggested that marine-derived GB-9 could be a helpful probiotic to control subclinical mastitis.