Influence of Eimeria maxima coccidia infection on gut microbiome diversity and composition of the jejunum and cecum of indigenous chicken

The Impact of Essential Amino Acids on the Gut Microbiota of Broiler Chickens

The research involving the beneficial aspects of amino acids being added to poultry feed pertaining to performance, growth, feed intake, and feed conversion ratio is extensive. Yet currently the effects of amino acids on the gut microbiota aren't fully understood nor have there been many studies executed in poultry to explain the relationship between amino acids and the gut microbiota. The overall outcome of health has been linked to bird gut health due to the functionality of gastrointestinal tract (GIT) for digestion/absorption of nutrients as well as immune response. These essential functions of the GI are greatly driven by the resident microbiota which produce metabolites such as butyrate, propionate, and acetate, providing the microbiota a suitable and thrive driven environment. Feed, age, the use of feed additives and pathogenic infections are the main factors that have an effect on the microbial community within the GIT. Changes in these factors may have potential effects on the gut microbiota in the chicken intestine which in turn may have an influence on health essentially affecting growth, feed intake, and feed conversion ratio. This review will highlight limited research studies that investigated the possible role of amino acids in the gut microbiota composition of poultry.

Effect of an Alliaceae Encapsulated Extract on Growth Performance, Gut Health, and Intestinal Microbiota in Broiler Chickens Challenged with Eimeria spp

This study analyzed the effects of an Alliaceae encapsulated extract (AE-e) on daily gain (ADG), feed intake (ADFI), feed conversion ratio (FCR), oocysts per gram of feces (OPG), intestinal lesion (LS), and microbiota composition in broilers challenged with Eimeria spp. A total of 4800 one day Cobb-500 were allotted into 10 treatment groups with 12 replicates of 40 birds in a 2 × 4 + 2 factorial arrangement. The first factor was non-challenged (NC) or challenged (C), the second was four levels of AE-e added in the basal diet, 0 (AE0), 250 (AE250), 500 (AE500), and 750 mg·kg-1 (AE750), plus two ionophore controls, non-challenged (NC-Ion) and challenged (C-Ion). No interactions were observed between factors (NC0, NC250, NC500, NC750, C0, C250, C500, and C750), while C-Ion improved FCR at 21 d. The challenge affected negatively ADG and FCR and promoted enteropathogens in cecum. AE750 improved FCR in the finisher and cumulative phases, while C-Ion had fewer total OPG than C0 and C250. Likewise, at 21d, C250, C500, and C-Ion had fewer LS than C0, while at 28 d, C750 showed lower than C-Ion. In the cecum microbiota, C500 had more Ruminococcus, Firmicutes b, and Intestinimonas than C-Ion. In summary, AE-e showed beneficial results in broilers infected with Eimeria spp.

Dietary peptide-specific antibodies against interleukin-4 differentially alter systemic immune cell responses during Eimeria challenge with minimal impacts on the cecal microbiota

Eimeria spp. induce host interleukin (IL)-4 production, a potent immune regulator, during coccidiosis to evade immune responses. Dietary anti-IL-4 may preserve bird performance during challenge; however, specific mechanisms have not been investigated. Study objectives were to develop peptide-specific anti-IL-4 antibodies and evaluate immune cell profiles and the cecal microbiota during Eimeria challenge. Four candidate IL-4 peptides were selected based on antigenicity and location. Hens were injected with conjugated peptide or carrier-only control (3/injection), eggs were collected post-vaccination and yolks were pooled by peptide before freeze-drying. On d 0, 300 Ross 708 broilers were placed in floor pens (10/pen) and assigned to 5 diets consisting of basal diet + 2% egg yolk powder containing antibodies against 1 of 4 target peptides or carrier-only control for 14-d starter and grower periods (28 d total). Baseline blood and cecal contents were collected on d 14 (6 birds/diet) before half the remainder were inoculated with 10X Coccivac-B52 (Merck Animal Health, Kenilworth, NJ). Body weight (BW) and feed intake (FI) were recorded weekly and blood and cecal samples were collected at 3, 7, and 14 d post-inoculation (pi; 3/treatment). Immune cell profiles in peripheral blood mononuclear cells (PBMC) were evaluated flow cytometrically and cecal microbial communities determined by 16S/18S rRNA gene amplicon sequencing. Data were log-transformed when necessary and analyzed with diet, Eimeria, and timepoint fixed effects plus associated interactions (SAS 9.4; P ≤ 0.05). Anti-IL-4 did not alter baseline performance but generally increased PBMC Bu-1+ B cells 38.0 to 55.4% (P < 0.0001). Eimeria challenge reduced FI and BWG 16.1 and 30.3%, respectively, regardless of diet (P < 0.0001) with only birds fed peptide 4 antibodies not recovering feed conversion by d 28. Minimal diet-associated cecal microbiota changes were observed, indicating that anti-IL-4 effects were likely host-specific. Eimeria-challenged birds fed peptide 3 antibodies displayed minimal immune cell fluctuations compared to unchallenged counterparts, suggesting these antibodies potentially modulated intestinal immune responses to minimize systemic requirements, making them good candidates for further research.

Gut microbiota in parasite-transmitting gastropods

BACKGROUND

Gastropoda, the largest class within the phylum Mollusca, houses diverse gut microbiota, and some gastropods serve as intermediate hosts for parasites. Studies have revealed that gut bacteria in gastropods are associated with various biological aspects, such as growth, immunity and host-parasite interactions. Here, we summarize our current knowledge of gastropod gut microbiomes and highlight future research priorities and perspectives.

METHODS

A literature search was undertaken using PubMed, Web of Science and CNKI for the articles on the gut microbiota of gastropods until December 31, 2022. We retrieved a total of 166 articles and identified 73 eligible articles for inclusion in this review based on the inclusion and exclusion criteria.

RESULTS

Our analysis encompassed freshwater, seawater and land snails, with a specific focus on parasite-transmitting gastropods. We found that most studies on gastropod gut microbiota have primarily utilized 16S rRNA gene sequencing to analyze microbial composition, rather than employing metagenomic, metatranscriptomic, or metabolomic approaches. This comprehensive review provided an overview of the parasites carried by snail species in the context of gut microbiota studies. We presented the gut microbial trends, a comprehensive summary of the diversity and composition, influencing factors, and potential functions of gastropod gut microbiota. Additionally, we discussed the potential applications, research gaps and future perspectives of gut microbiomes in parasite-transmitting gastropods. Furthermore, several strategies for enhancing our comprehension of gut microbiomes in snails were also discussed.

CONCLUSIONS

This review comprehensively summarizes the current knowledge on the composition, potential function, influencing factors, potential applications, limitations, and challenges of gut microbiomes in gastropods, with a specific emphasis on parasite-transmitting gastropods. These findings provide important insights for future studies aiming to understand the potential role of gastropod gut microbiota in controlling snail populations and snail-borne diseases.

Natural Magnolol ameliorates coccidiosis infected with Eimeria tenella by affecting antioxidant, anti-inflammatory, and gut microbiota of chicks

Magnolol, a natural extract from magnolia officinalis, has received growing interest in its bioactive properties such as antioxidant, anti-inflammatory, and antibacterial activities. Nevertheless, there is little research on Magnolol in the treatment of parasitic infections currently. Eimeria tenella (E. tenella) infection causes damage to epithelial cells and cecal mucosa, resulting in increased intestinal permeability, which is pretty detrimental to the balance of the intestinal microenvironment. However, at present, in the treatment of chicken coccidiosis, the abuse of antibiotics is quite serious, which has brought losses and harms to the chicken farming industry that cannot be ignored. In this study, based on the excellent antioxidant and anti-inflammatory properties of Magnolol, we proved that it does have a desirable therapeutic potential on chicks infected with E. tenella. Actually, the results showed that the clinical symptoms of the chicks infected with E. tenella were relieved and their growth performance was restored by Magnolol treatment. Furthermore, Magnolol improved the antioxidant and anti-inflammatory properties of chicks. Meanwhile, the Magnolol reversed the imbalance of the intestinal microbiota of sick chicks, which recovered the diversity, promoted the potential beneficial bacteria, and inhabited the potential pathogenic bacteria. Overall, Magnolol may be an alternative to chemical drugs that are effective in treating E. tenella infections.

Comprehensive analysis of gut microbiome and host transcriptome in chickens after Eimeria tenella infection

Background

Coccidiosis is an intestinal parasitic disease caused by Eimeria protozoa, which endangers the health and growth of animals, and causes huge economic losses to the poultry industry worldwide every year. Studies have shown that poultry gut microbiota plays an important role in preventing the colonization of pathogens and maintaining the health of the host. Coccidia infection also affects host gene expression. However, the underlying potential relationship between gut microbiome and host transcriptome during E. tenella infection in chickens remain unclear.

Methods

In this study, metagenomic and transcriptome sequencing were applied to identify microbiota and genes in cecal contents and cecal tissues of infected (JS) and control (JC) chickens on day 4.5 postinfection (pi), respectively.

Results

First, microbial sequencing results of cecal contents showed that the abundance of Lactobacillus, Roseburia sp. and Faecalibacterium sp decreased significantly after E. tenella infection (P < 0.05), while the abundance of Alistipes and Prevotella pectinovora increased significantly (P < 0.05). Second, transcriptome sequencing results showed that a total of 434 differentially expressed mRNAs were identified, including 196 up-regulated and 238 down-regulated genes. These differentially expressed genes related to inflammation and immunity, such as GAMA, FABP1, F2RL1 and RSAD2, may play an important role in the process of host resistance to coccidia infection. Functional studies showed that the enriched pathways of differentially expressed genes included the TGF-beta signaling pathway and the ErbB signaling pathways. Finally, the integrated analysis of gut microbiome and host transcriptome suggested that Prevotella pectinovora associated with FABP1, Butyricicoccus porcorum and Colidextribacter sp. associated with RSAD2 were involved in the immune response upon E. tenella infection.

Conclusion

In conclusion, this study provides valuable information on the microbiota and key immune genes after chicken E. tenella infection, with the aim of providing reference for the impact of coccidia infection on cecal microbiome and host.