Construction of and evaluation of the immune response to two recombinant pseudorabies viruses expressing the B119L and EP364R proteins of African swine fever virus.

African swine fever (ASF) is an infectious disease caused by ASF virus (ASFV), which is characterized by high infectivity, rapid onset of disease, and a high mortality rate. Outbreaks of ASFV have caused great economic losses to the global pig industry, and there is a need to develop safe and effective vaccines. In this study, two recombinant pseudorabies virus (PRV) strains, rGXGG-2016-ΔgI/ΔgE-EP364R and rGXGG-2016-ΔgI/ΔgE-B119L, expressing the EP364R and B119L protein, respectively, of ASFV, were constructed by homologous recombination technology. Western blotting and immunofluorescence analysis showed that these foreign proteins were expressed in cells infected with the recombinant strains. The strains showed good genetic stability and proliferative characteristics for 20 passages in BHK-21 cells. Both of these strains were immunogenic in mice, inducing the production of specific antibodies against the expressed ASFV proteins while providing protection against lethal challenge with PRV. Thus, the recombinant strains rGXGG-2016-ΔgI/ΔgE-EP364R and rGXGG-2016-ΔgI/ΔgE-B119L could be used as candidate vaccines for both ASFV and PRV. In addition, our study identifies two potential target genes for the development of safe and efficient ASFV vaccines, provides a reference for the construction of bivalent ASFV and PRV vaccines, and demonstrates the feasibility of developing a live ASFV vector vaccine.

Description of Gut Mycobiota Composition and Diversity of Caprinae Animals.

The fungal community, also known as mycobiota, plays pivotal roles in host nutrition and metabolism and has potential to cause disease. However, knowledge of the gut fungal structure in Caprinae is quite limited. In this study, the composition and diversity of the gut mycobiota of Caprinae animals from different geographical locations (Anhui, Jilin, Guangxi, Shandong, Shanxi, and Tibet) were comprehensively characterized by analyzing the internal transcribed spacer 2 (ITS-2) sequences of the fungal community. The results showed that Ascomycota and Basidiomycota were the dominant phyla, which, respectively, accounted for 90.86 to 95.27% and 2.58 to 7.62% of sequences in samples from each region. Nonetheless, the structure of the gut mycobiota was largely different in Caprinae animals in the different provinces. Therein, Sporormiaceae and Thelebolaceae were the dominant fungal families in the samples from Tibet, whereas their abundance was generally low in other regions. The intestinal diversity of individuals from Guangxi was higher than that in other regions. In addition, there were 114 differential genera among all regions. Finally, the co-occurrence network revealed 285 significant correlations in cross-family pairs in the guts of Caprinae animals, which contained 149 positive and 136 negative relationships, with 96 bacterial and 86 fungal participants at the family level. This study has improved the understanding of the mycobiota of ruminants and provided support for the improvement in animal health and productivity. IMPORTANCE In this study, we elucidated and analyzed the structure of the gut mycobiota of Caprinae animals from different regions. This study revealed differences in the structure of the gut mycobiota among Caprinae animals from different geographical environments. Based on previous findings, correlations between fungal and bacterial communities were analyzed. This study adds to previous research that has expanded the present understanding of the gut microbiome of Caprinae animals.

Prevalence and related factors of Enterocytozoon bieneusi in cattle: A global systematic review and meta-analysis.

Enterocytozoon bieneusi (E. bieneusi) is an important zoonotic microsporidian pathogen that has a variety of hosts. Cattle are reservoir hosts of E. bieneusi, and play an important role in the epidemiology of E. bieneusi. However, no systematic research on the prevalence of E. bieneusi in cattle has been reported. Here, a systematic review and meta-analysis was performed to determine the prevalence of E. bieneusi in cattle. Six databases (PubMed, Web of Science, Springlink, Wanfang, CNKI, and VIP) were used for searching for relevant studies. The quantity of E. bieneusi infection in cattle was extracted and subjected to an estimation for the prevalence in cattle by using a random effects model. In total, forty articles from 12 countries were chosen from 524 studies from inception to 1st June 2021. An overall E. bieneusi prevalence (95% CI) in cattle was 12.9% (2566/19,791, 9.0-14.6%). The highest prevalence of E. bieneusi was 17.3% (13.9-20.3) in South America, and the lowest was 6.5% (4.1 - 9.4) in Africa 6.5%. The prevalence of E. bieneusi after 2016 (11.1%) was lower than 2016 and before (12.3%). Cattle aged 3-12 months had a higher prevalence (14.8%) as compared with cattle aged > 12 months (8.2%). The combined prevalence of E. bieneusi in the dairy cattle was 14.4%, which was higher than that in other species. In the subgroup of season, E. bieneusi prevalence in cattle was higher in spring (17.4%) and autumn (19.7%) than in summer (8.5%) and winter (8.5%). E. bieneusi prevalence in naturally grazed cattle was 3.6% and 13.7% in intensively fed cattle. A total of 83 E. bieneusi genotypes were prevalent in cattle, of which 15 genotypes found in the cattle had previously been found in humans. The global prevalence of E. bieneusi in cattle related to geographical and climate variables were evaluated as well. These data indicated that E. bieneusi was ubiquitous in cattle worldwide and carried a potential risk of infection in humans. Thus, the farm managers should provide a scientific mix of nutrients to improve cattle immunity, keep the environment clean, and disinfect regularly. Collectively, the control of E. bieneusi transmission in cattle is of importance for economic and public health.

Changes of gut microbiota structure in rats infected with Toxoplasma gondii.

Toxoplasma gondii (T. gondii) infection can cause intestinal inflammation in rodents and significantly alters the structure of gut microbiota. However, the effects of different T. gondii genotypes on the gut microbiota of rats remain unclear. In this study, acute and chronic T. gondii infection in Fischer 344 rats was induced artificially by intraperitoneal injection of tachyzoites PYS (Chinese 1 ToxoDB#9) and PRU (Type II). Fecal 16S rRNA gene amplicon sequencing was employed to analyze the gut microbiota structure at different stages of infection, and to compare the effects of infection by two T. gondii genotypes. Our results suggested that the infection led to structural changes of gut microbiota in rats. At the acute infection stage, the microbiota diversity increased, while both diversity and abundance of beneficial bacteria decreased at the chronic infection stage. The differences of microbiota structure were caused by strains of different genotypes. However, the diversity changes were consistent. This study demonstrates that the gut microbiota plays an important role in T. gondii infection in rats. The data will improve our understanding of the association between T. gondii infection and gut microbiota in rodents.

Dynamic description of temporal changes of gut microbiota in broilers.

The diversity of bacteria and fungi in the gut microbiota of commercial broilers that raised in cages from hatch to the end of the production cycle were examined by an analysis of 3,592 and 3,899 amplicon sequence variants (ASVs), respectively. More than 90% sequences in bacterial communities were related to Firmicutes and Proteobacteria. More than 90% sequences in fungal communities were related to Ascomycota, Basidiomycota, and Glomeromycota. A statistical analysis of the microbiota composition succession showed that age was one of the main factors affecting the intestinal microbial communities of broilers. The increasingly complex community succession of transient microbiota occurred along with an increase of age. This dynamic change was observed to be similar between bacteria and fungi. The gut microbiota had a special structure in the first 3 d after birth of broiler. The microbiota structure was quite stable in the period of rapid skeletal growth (d 14-21), and then changed significantly in the period of rapid gaining weight (d 35-42), thus indicating the composition of gut microbiota in broilers had unique structures at different developmental stages. We observed that several bacteria and fungi occupied key functions in the gut microbiota of broilers, suggesting that the gut homeostasis of broilers might be affected by losses of bacteria and fungi via altering interactions between microbiota. This study aimed to provide a data basis for manipulating the microbiota at different developmental stages, in order to improve production and the intestinal health of broilers.

Prevalence of bovine rotavirus among Bovidae in China during 1984-2021: A systematic review and meta-analysis.

Bovine rotavirus (BRV) is a potential zoonotic intestinal pathogen that brings a serious threat to calf health, and has resulted in huge economic losses to China's breeding industry. Here, a systematic review and meta-analysis was conducted to estimate the prevalence of BRV among Bovidae from 1984 to 2021 in China. A total of 64 publications on BRV investigation in China were screened from the databases Chinese National Knowledge Infrastructure (CNKI), Wan Fang Database, Technology Periodical Database (VIP), PubMed, and ScienceDirect. The random-effect model was used to calculate the pooled prevalence of BRV, and the analyzed data were derived from 25 provinces in China. The estimated pooled prevalence of BRV in China was 35.7% (8176/17,292). In addition, the prevalence of BRV in Southwestern China (77.1%; 2924/3600) was significantly higher than that in other regions of China. Regarding geographic and climatic factors, the prevalence of BRV in the subgroup of latitude 30-35° (76.8%; 3303/4659) was significantly higher than that in the subgroup of latitude less than 30° (37.0%; 485/1275) or more than 35° (32.6%; 1703/5722), while the prevalence of BRV in the subgroup of longitude 100-105° (75.4%; 2513/3849) was significantly higher than that in the subgroup of longitude less than 100° (32.6%; 619/2255) or more than 105° (48.9%; 2359/5552). Rainfall was positively correlated with the prevalence of BRV, whereas temperature was negatively correlated with the positive rate of BRV (P < 0.05). Our data showed that the prevalence of BRV was strongly correlated with geographical and climatic conditions. Thus, we recommend that the corresponding prevention and control programs should be formulated according to different geographical conditions. The strengthening of BRV surveillance in areas with high altitude, low temperature, and heavy rainfall may contribute to the decrease of the incidence of BRV infection among Bovidae herds in China.

Prevalence of Giardia duodenalis Among Dogs in China from 2001 to 2021: A Systematic Review and Meta-Analysis.

Giardia duodenalis has a wide range of host species and is a common causative agent of diarrheal disease in humans and animals. This study conducted a systematic review and meta-analysis to evaluate the pooled prevalence of Giardia among dogs in China. We extracted 33 studies related to the prevalence of G. duodenalis in dogs, with samples taken from 2001 to 2021. The random-effect model was used to calculate pooled prevalence estimates with 95% confidence intervals, and the analyzed data were from 14 provinces in China. The estimated overall prevalence of G. duodenalis among dogs in China was 11.2%. The prevalence of Giardia was significantly higher in Northwestern China (35.7%) than in other regions. The prevalence in 2010 or later (11.8%) was significantly higher than in 2010 or before (6.9%). The estimated prevalence detected by microscopy (9.3%) was lower than molecular (12.3%) and serological (14.3%) ones. The prevalence was higher in dogs <1 year of age (12.2%) than that >1 year (5.4%). Among the genotype groups, the positive rate of assemblage A (5.2%) was significantly higher than that of other assemblages. Depending on the dog' type, the prevalence of G. duodenalis in stray dogs (3.5%) was lower than that in pet dogs (6.7%) and intensively breeding dogs (11.8%). In addition, no correlation was found between Giardia positive rate and the dogs' gender (p > 0.05). We also analyzed the effects of different geographic factor subgroups (longitude, latitude, precipitation, temperature, humidity, and altitude) on the prevalence of G. duodenalis in dogs in China. The results showed that giardiasis was widespread in dogs in China. It is suggested that corresponding control scheme and effective management measures should be formulated and applied to reduce the transmission of G. duodenalis according to the difference in geographical conditions in different areas.

The global prevalence and risk factors of Cryptosporidium infection among cats during 1988-2021: A systematic review and meta-analysis.

Cryptosporidiosis is an important zoonosis caused by Cryptosporidium. This disease causes a global public health problem. The cat is considered to be one of the potential hosts for transmitting Cryptosporidium to humans. In this study, a global meta-analysis for Cryptosporidium infection in cats was performed. The articles related to Cryptosporidium infection in cats were systematically searched in databases China National Knowledge Infrastructure (CNKI), Wanfang data, VIP Chinese Journal Database, PubMed, and ScienceDirect. Finally, 92 articles published from 1988 to 2021, which met the criteria of systematic review and meta-analysis, were collected. During the selected period, the overall prevalence of Cryptosporidium among cats was identified to be 6.0%. The prevalence of Cryptosporidium detected by microscopy, coproantigens, and molecular biology methods were 4.2%, 8.2%, and 5.0%, respectively. Among 9 species/genotypes (C. felis, C. parvum, C. muris, Cryptosporidium rat genotype IV, C. baileyi, C. ryanae, C. hominis, Cryptosporidium sp. rat genotype III and most closely related to Cryptosporidium sp. rat genotype III), the prevalence of C. parvum (4.2%) was significantly higher than that of other species/genotypes. Among five continents, the prevalence of Cryptosporidium in Africa (30.5%) was significantly higher than in other continents. We also analyzed the effects of different geographical factors (longitude, latitude, altitude, mean temperature, precipitation, and humidity) on Cryptosporidium infection among cats. The results showed that cryptosporidiosis was common in cats all over the world. This systematic review and meta-analysis has systematically introduced the global epidemiology of Cryptosporidium in cats and correlated risk factors. Health authorities, doctors, veterinarians and cat owners' awareness of the prevalence, risk factors and complications of Cryptosporidium are important for the development of effective prevention strategies for cryptosporidiosis.

Total Flavonoids of Glycyrrhiza uralensis Alleviates Irinotecan-Induced Colitis via Modification of Gut Microbiota and Fecal Metabolism.

Irinotecan (CPT-11)-induced gastrointestinal toxicity strongly limits its anticancer efficacy. Glycyrrhiza uralensis Fisch., especially flavonoids, has strong anti-inflammatory and immunomodulatory activities. Herein, we investigate the protective effect of the total flavonoids of G. uralensis (TFGU) on CPT-11-induced colitis mice from the perspective of gut microbiota and fecal metabolism. The body weight and colon length of mice were measured. Our results showed that oral administration of TFGU significantly attenuated the loss of body weight and the shortening of colon length induced by CPT-11. The elevated disease activity index and histological score of colon as well as the up-regulated mRNA and protein levels of TNF-α, IL-1ß, and IL-6 in the colonic tissue of CPT-11-treated mice were significantly decreased by TFGU. Meanwhile, TFGU restored the perturbed gut microbial structure and function in CPT-11-treated mice to near normal level. TFGU also effectively reversed the CPT-11-induced fecal metabolic disorders in mice, mainly call backing the hypoxanthine and uric acid in purine metabolism. Spearman's correlation analysis further revealed that Lactobacillus abundance negatively correlated with fecal uric acid concentration, suggesting the pivotal role of gut microbiota in CPT-11-induced colitis. Since uric acid is a ligand of the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome, TFGU was further validated to inhibit the activation of NLRP3 inflammasome by CPT-11. Our findings suggest TFGU can correct the overall gut microbial dysbiosis and fecal metabolic disorders in the CPT-11-induced colitis mice, underscoring the potential of using dietary G. uralensis as a chemotherapeutic adjuvant.