Search

ABSTRACT: Novel Duck Reovirus (NDRV) that has been found throughout the world in waterfowl, and it has been extensively described. Here, we report the complete genome sequence of a NDRV strain isolated in China called NDRV YF10. This strain was collected from 87 samples with infected ducks in South Coastal Area. The NDRV genome consists of 23,419 bp. With the assistance of computer analysis, the promoter and terminator of each gene segment and 10 viral genes segments were identified, which encode polypeptides ranging from 98 to 1,294 amino acids. All gene fragments of this virus strain were determined and compared to previously reported strains, revealing genetic variation with similarity rates ranging from 96 to 99% for each gene segment. Each gene segment formed 2 host-associated groups, the waterfowl-derived reovirus and the avian-derived reovirus, except for the S1 gene segment, which was closely related to ARV evolution and formed a host-independent subcluster. This difference may be due to Avian Reovirus (ARV) evolving in a host-dependent manner. In order to evaluate the pathogenicity of YF10, a novel isolated strain of NDRV was tested in 2 types of ducks. It was observed that the YF10 isolated strain exhibits varying degrees of virulence, highlighting the potential risk posed to different types of ducks. In conclusion, our findings emphasize the importance of epidemiology studies, molecular characterization, and prevention of NDRV in waterfowl.

ABSTRACT: Intestinal damage from the duck plague virus (DPV) infection affects intestinal inflammation factors expression and barrier dysfunction. Here we report findings from the pathogenicity of the intestinal tract, intestinal morphological, intestinal permeability, inflammatory cytokines, and tight junction gene expression in 72 two-wk-old Muscovy ducks exposed to DPV. The characterization of intestinal metabolites and their classification were examined using 16-sequencing technology. The primary outcomes of the study evaluated the correlation between intestinal microbiota characteristics and the degree of infected tissue. The secondary outcomes were to determine whether the biosignatures that defined the microbiota were positively or negatively correlated with viral infection. The tissue was infected accompanied a mild damage of liver and spleen, and severe intestinal bleeding. Two inoculation routes were constructed with susceptible animals to assess the pathogenicity of the DPV in order to enrich the status of infection in Muscovy ducks. High levels of virus titer from Muscovy ducks were found being in the intestine. The expression of INF-α and IL-β with viral infection increased at 4, and 6 dpi, respectively, after detecting of the inflammatory factor and barrier function genes. At 4 and 6 dpi, barrier function gene of ZO-1 and Occludin reduced. The severity of viral infection was significantly correlated with the characteristics of the intestinal microbiota. Ducks infected with the DPV had an increase in the phylum Firmicutes, a decrease in the phylum Actinobacteriota, and differential enrichment with the genus Bacteroides, Tyzzerella, Enterococcus, and Escherchia-Shigella, while the genus Rothia, Streptococcus, and Ralstonia were differentially enriched in the control group. The findings from the current study demonstrated that DPV infection leads to an imbalance of the intestinal microbiota and disruption of the microbial homeostasis in the intestinal tissue in ducks, which might be one of the mechanisms whereby DPV infection might be established in Muscovy ducks. Na+/K+-ATPase and Ca2+/Mg2+-ATPase activity monitoring also showed that viral infection reduced these activities. These findings imply that changes in intestinal microbiota, intestinal barrier gene expression, and inflammatory factor are related to viral infection. When taken as a whole, this work provides fresh perspectives on the characteristics of intestinal microbiota and the infection damage caused by the DPV.

ABSTRACT: H9N2 subtype avian influenza virus (AIV) is a low pathogenic AIV, which is widely prevalent all over the world. The infection of H9N2 AIV often leads to secondary infection with other pathogens, causing serious economic losses to poultry industry. Up to now, several recombinant Newcastle disease viruses (NDV) expressing H9N2 AIV hemagglutinin (HA) protein had been developed. However, the efficacy of recombinant virus on tracheal and intestinal injury caused by H9N2 AIV was rarely reported. The aim of this study was to evaluate the efficacy of recombinant NDV expressing H9N2 AIV HA protein in respiratory and intestinal tract. In this study, based on Red/ET homologous recombination technology, H9N2 AIV HA gene was embedded into the genome of NDV LaSota vaccine strain to obtain the recombinant virus rNDV-H9. The recombinant virus rNDV-H9 showed similar replication kinetic characteristics with the parent LaSota strain and had good genetic stability. The immunization result showed that rNDV-H9 induced high HI antibody titer against H9N2 AIV. In the H9N2 AIV challenge experiment, rNDV-H9 could significantly reduce the virus shedding in trachea and cloaca. In addition, rNDV-H9 protected the barrier function of chicken intestinal mucosal epithelial cells and reduced the virus-induced inflammatory response to a certain extent, so as to inhibit the abnormal proliferation of E. coli. This study suggests that rNDV-H9 is a promising vaccine candidate against H9N2 AIV.

To study the effects of antibacterial peptides (ABPs) on feeding broilers, this experiment compared the 2 combinations of ABP with antibiotics by separately adding the supplement to the diet of 818 broilers as follows—antibiotics, Pratt and Full-tide, and Pratt and plant essential oil—and then the effect of them on production performance, immune function, antioxidant capacity, serum biochemical indicators, and microorganisms of the experimental flocks was investigated and compared. It was found that the aforementioned indicators among the 2 groups of ABP and the antibiotic group were close to or even better than those of antibiotics, and the combination added with plant essential oils had generally better effects. These results indicated that ABPs could improve economic benefits by promoting growth, preventing disease, and reducing the rate of death. This study deepened the research on the action mechanism of ABPs and not only explored the feasibility of ABPs as a novel feed additive for broilers but also provided experimental data and theoretical basis for the application of ABPs.

The goal of the study was testing the effects of chlorogenic acid (CA) supplementation on small intestine healthiness, growth performance, oxidative stress, inflammatory response, and blood biochemical indices in specific-pathogen-free (SPF) chickens after infection with Clostridium perfringens (CP) type A. In this study, 324 1-day-old male SPF chickens were randomly distributed into 6 groups: control group; CA group; CP infection group; CA + CP group; antibiotic group; antibiotic + CP group. All 1-day-old chickens were fed with CA or antibiotic in corresponding treatment group for 13 d. On the 14 d, the chickens in corresponding infection group were challenged with CP type A for 3 d. Samples in each group were collected when the chickens were 17 and 21 d old. This study proves for the first time that CA, a Chinese herbal medicine, can effectively improve growth performance, inhibit small intestine structural damage, improve antioxidant capacity, inhibit damage to ileal mucosal layer construction and tight junctions, inhibit inflammatory cytokines, and ameliorate blood biochemical indices. Therefore, this study provides data for CA being able to effectively alleviate small intestine damage caused by CP type A infection in chickens.

A novel homogeneous polysaccharide, designated as PLPN-2, was screened from the dried root of Paeonia lactiflora Pall. using an activity-oriented approach, demonstrating remarkable anti-inflammatory properties. Structural analysis revealed that PLPN-2 is an α-glucan comprising an α-(1 → 4)-glucan backbone with α-Glcp-(1→/α-Glcp-(1 → 6)-β-Glcp-(1→ linked to the backbone at C-6. PLPN-2 exhibited efficacy in alleviating inflammatory symptoms associated with DSS-induced colitis in mice and inhibiting the release of pro-inflammatory elements including IL-6, TNF-α, IL-1β from RAW264.7 macrophages promoted by LPS. Moreover, PLPN-2 demonstrated ability to impede the nuclear translocation of the p65 protein and reduce the phosphorylation levels of JNK, ERK1/2, p38, p65, and IκBα. The findings suggest that PLPN-2 exhibits potential as an anti-inflammatory agent through the inhibition of the MAPK and NF-κB signaling pathways. Therefore, PLPN-2 shows promising prospects as a functional agent for relieving inflammation-related disorders.

The rhizome of Polygonatum sibiricum is traditionally used as a tonic-type edible herb. In this study, a homogenous polysaccharide (PSPW) was isolated from P. sibiricum. PSPW primarily consisted of fructose and glucose in a molar ratio of 18:1 with a molecular weight of 14.35 kDa. PSPW presented a triple-helical conformation with a rough surface and hill-shaped microstructure. Furthermore, after oral administration of PSPW, the serum levels of fasting blood glucose, glycosylated serum protein and insulin were respectively decreased by 22.5%, 28.4%, and 46.4%, and glucagon-like peptide-1 (GLP-1) secretion showed a 1.7-fold increase in type 2 diabetic (T2D) mice. The glucose tolerance, insulin sensitivity, and hepatic glucose metabolism were improved by PSPW treatment. The elevated PI3K and Akt phosphorylation and reduced FoxO1 and GSK3β phosphorylation were found in liver of PSPW-treated T2D mice, suggesting the potential hypoglycemic mechanism of PSPW may be associated with the activation of insulin-mediated PI3K/AKT signaling pathway.