The gastrointestinal tract of felines is inhabited by an active and intricate population of microorganisms whose alteration creates disturbances in the immune response and can affect health and disease states. Studies using various analytical methods have identified peculiar trends in various illnesses, with Firmicutes being the most prevalent phylum, followed by Bacteroidetes, Proteobacteria, and Actinobacteria. However, more Firmicutes and fewer Bacteroidetes have been observed in cats infected with Feline coronavirus. Alterations in the composition of these gut microbiota can be solved by microbiota modification through dietary fiber, probiotics, and fecal microbiota transplantation. Therefore, it is critical to understand the composition of the gut microbiota, the changes in and roles of the gut environment, and the importance of these concepts for overall health while considering the exchange of microbes between humans and domestic animals. This review provides comprehensive information on feline gut microbiota composition, modulation, and analytic methods used for characterizing the gut microbiota.

Porcine reproductive and respiratory syndrome virus (PRRSV) infection causes significant economic loss to the global pig industry. Genotype 1 and 2 PRRSV (PRRSV-1 and -2) infections have been reported in China, Europe and America. For accurate prevention, nanobodies were first used as diagnostic reagents for PRRSV typing. In this study three nanobodies targeting both PRRSV-1 and -2, two targeting PRRSV-1 and three targeting PRRSV-2, were screened and produced. To develop two competitive ELISAs (cELISAs), the g1-2-PRRSV-Nb3-HRP nanobody was chosen for the g1-2-cELISA, to detect common antibodies against PRRSV-1 and -2, and the g1-PRRSV-Nb136-HRP nanobody was chosen for the g1-cELISA, to detect anti-PRRSV-1 antibodies. The two cELISAs were developed using PRRSV-1-N protein as coating antigen, and the amounts for both were 100 ng/well. The optimized dilution of testing pig sera was 1:20, the optimized reaction times were 30 min, and the colorimetric reaction times were 15 min. Then, the cut-off values of the g1-2-cELISA and g1-cELISA were 26.6% and 35.6%, respectively. Both of them have high sensitivity, strong specificity, good repeatability, and stability. In addition, for the 1534 clinical pig sera, an agreement rate of 99.02% (Kappa values=0.97) was determined between the g1-2-cELISA and the commercial IDEXX ELISA kit. For the g1-cELSIA, it can specifically detect anti-PRRSV-1 antibodies in the clinical pig sera. Importantly, combining two nanobody-based cELISAs can differentially detect antibodies against PRRSV-1 and -2.

Enterotoxigenic E. coliis one of the bacterial pathogens contributing to the global resistance crisis in public health and animal husbandry. The problem of antibiotic resistance is becoming more and more serious, and phage is considered one of the potential alternatives to antibiotics that could be utilized to treat bacterial infections. Our study isolated and identified a lytic phage PGX1 against multidrug-resistant enterotoxigenic E. coliEC6 strain from sewage. The phage lysis profile revealed that PGX1 exhibited a lytic effect on multidrug-resistant enterotoxigenic E. colistrains of serotype O60. Through phage whole genome sequencing and bioinformatics analysis, PGX1 was found to be the class Caudoviricetes, family Autographiviridae,genus Teseptimavirus. The length of the PGX1 genome is about 37,009 bp, containing 54 open reading frames (ORFs). Notably, phage PGX1 lacks any lysogenic-related genes or virulence genes. Furthermore, phage PGX1 demonstrates strong adaptability, tolerance, and stability in various pH (pH4-10) and temperatures (4-40°C). The in vivo and in vitro tests demonstrated that phage PGX1 significantly removes and inhibits the formation of multidrug-resistant EC6 biofilm and effectively controls the Galleria mellonellalarvae and enterotoxigenic E. coliEC6 during mice infection. In conclusion, the above findings demonstrated that phage PGX1 may be a novel antimicrobial agent to control multidrug-resistant E. coliinfections.

Trypanosoma cruziis the etiologic agent of Chagas disease. This flagellated protozoan is transmitted to humans as well as different species of domestic and wild animals viavectors from the Reduviidae family (known as “kissing bugs”). Despite the fact that hundreds of species of wild mammals are part of the reservoir system, the morphological changes and clinical manifestations resulting from the pathogenesis of the infection have been largely neglected. The aim of this review is to systematically compile the available information regarding clinicopathological alterations in wild mammals due to natural infection by T. cruzi. Information was obtained from six online bibliographic data search platforms, resulting in the identification of 29 publications that met the inclusion criteria. Mortality was the most common clinical manifestation, cardiac damage was the main finding at necropsy, and lymphoplasmacytic inflammation was the most frequent microscopic injury. Thus, regardless of its role as a reservoir, T. cruzihas the potential to affect the health status of wild mammals, a situation that highlights the need for further research to analyze, measure, and compare its effects at both the individual and population levels.

Feline panleukopenia virus (FPV) is a single-stranded DNA virus that can infect cats and cause feline panleukopenia, which is a highly contagious and fatal disease in felines. The sequence of FPV is highly variable, and mutations in the amino acids of its capsid protein play crucial roles in altering viral virulence, immunogenicity, host selection, and other abilities. In this study, the epidemiology of FPV was studied using 746 gastrointestinal swab samples derived from cats that presented gastrointestinal symptoms specifically, diarrhea or vomiting during the period spanning from 2018 to 2022. The overall prevalence of FPV-positive patients among these samples was determined to be 45.4%. Capsid (virion) protein 2 (VP2) gene of each FPV-positive sample was sequenced and amplified, yielding 65 VP2 sequences. Among them, six VP2 gene sequences were detected in the majority of the samples test positive for FPV, and these positive samples originated from a diverse range of geographical locations. These isolates were named FPV-6, FPV-10, FPV-15, FPV-251, FPV-271 and FPV-S2. Additionally, the substitution of Ala300Pro (A300P) in VP2 was detected for the first time in feline-derived FPV (FPV-251). FPV-251 isolate, with this substitution in VP2 protein, exhibited stable proliferative capacity in Madin-Darby canine kidney (MDCK) cells and A72 cells. FPV-271 was selected as the FPV control isolate due to its single amino acid difference from VP2 protein of FPV-251 at position 300 (FPV-271 has alanine, while FPV-251 has proline). After oral infection, both FPV-251 and FPV-271 isolates caused feline panleukopenia, which is characterized by clinical signs of enterocolitis. However, FPV-251 can infect dogs through the oral route and cause gastrointestinal (GI) symptoms with lesions in the intestine and mesenteric lymph nodes (MLNs) of infected dogs. This is the first report on the presence of an A300P substitution in VP2 protein of feline-derived FPV. Additionally, FPV isolate with a substitution of A300P at VP2 protein demonstrated efficient replication capabilities in canine cell lines and the ability to infect dogs.

The widespread occurrence of carbapenem-resistant organisms has garnered significant public attention. Arthropods, including flies, are important vectors of multidrug-resistant bacteria. In this study, we reported the simultaneous carriage of four carbapenem-resistant isolates from different species, namely, Escherichia coli( E. coli), Providencia manganoxydans( P. manganoxydan), Myroides odoratimimus( M. odoratimimus) and Proteus mirabilis( P. mirabilis), from a single fly in China. These isolates were characterized through antimicrobial susceptibility testing, conjugation assays, whole-genome sequencing, and bioinformatics analysis. M. odoratimimusshowed intrinsic resistance to carbapenems. The mechanisms of carbapenem resistance in E. coli, P. manganoxydans, and P. mirabiliswere due to the production of NDM-5, NDM-1 and NDM-1, respectively. Genetic context of the bla _NDM genes in these three isolates varied. The bla _NDM-5 gene in E. coliwas located on an IncHI2/HI2A multidrug-resistant plasmid, which was conjugatively transferable. The bla _NDM-1 gene in P. mirabilisresided on the pPM14-NDM_123k-like nonconjugative plasmid. The bla _NDM-1 gene in P. manganoxydanswas found in a nonconjugatively transferable, multidrug-resistant region. The results of this study enhance our understanding of the dissemination of carbapenem-resistant organisms and suggest the need for a more comprehensive approach to antibiotic resistance research encompassing humans, animals, and the environment.

Porcine deltacoronavirus (PDCoV) is a swine enteropathogenic CoV that causes severe vomiting, diarrhea and dehydration in suckling piglets, leading to economic losses in the swine industry. There is a great need for a convenient method to detect circulating antibodies and help in accurate diagnosis and disease control. Previously, we demonstrated that a unique PDCoV accessory protein, NS6, is expressed during PDCoV infection in pigs and is incorporated into PDCoV virions; thus, we deduced that NS6 is likely an immunogenic target that can be used for the diagnosis of PDCoV infection. In this study, we first confirmed that NS6 is immunogenic in PDCoV-infected pigs by performing a serum western blot. Furthermore, we developed a novel NS6-based indirect enzyme-linked immunosorbent assay (iELISA) method and compared it to an established S1-based iELISA for the survey of anti-PDCoV IgG or IgA in pigs of different ages in China. The NS6-iELISA has high specificity for the detection of IgG antibodies and no cross-reactivity with other porcine enteric CoVs (transmissible gastroenteritis coronavirus, porcine epidemic diarrhea virus, or swine acute diarrhea syndrome coronavirus). This NS6 serology-based method has great sensitivity and good repeatability, making it a new and cost-saving option for the rapid diagnosis and immunosurveillance of PDCoV, which may also be important for the prevention and control of deltacoronavirus-related infection in pigs and other animals.

Lactobacillusspecies have excellent abilities to reduce intestinal inflammation and enhance gut barrier function. This study elucidated the potential mechanisms through which Lactobacillusmitigates lipopolysaccharide (LPS)-induced intestinal injury from the perspective of macrophage-intestinal epithelial cell interactions. Lactobacillusintervention improved the histopathological score; elevated ZO-1 and Occludin protein production; reduced CD16⁺ cell numbers; diminished IL-1β, IL-6, and TNF-α levels; decreased inducible nitric oxide synthase (iNOS) expression; increased CD163⁺ cell numbers; elevated IL-10 concentration; and increased arginase-1 (Arg1) expression in LPS-challenged piglets. Lactobacilluspretreatment also altered the colonic microbiota, thereby increasing the butyric acid concentration and GPR43 expression in the LPS-challenged piglets. Compared with those in the LPS group, sodium butyrate (SB) pretreatment decreased IL-1β, IL-6 and TNF-α secretion and iNOS expression but increased IL-10 secretion and Arg1 expression in macrophages. The SB-pretreated macrophages reduced the protein expression of TLR4, MyD88, and phosphorylated NF-κB p65 but increased the protein expression of ZO-1 and Occludin in intestinal epithelial cells. Moreover, GLPG0974 blocked the beneficial effects of SB on macrophages and intestinal epithelial cells. This study demonstrated that Lactobacillusimproves intestinal barrier function by regulating the macrophage phenotype through the control of butyric acid and GPR43 levels to further control inflammation.

As a new data management paradigm, knowledge graphs can integrate multiple data sources and achieve quick responses, reasoning and better predictions in drug discovery. Characterized by powerful contagion and a high rate of morbidity and mortality, porcine reproductive and respiratory syndrome (PRRS) is a common infectious disease in the global swine industry that causes economically great losses. Traditional Chinese medicine (TCM) has advantages in low adverse effects and a relatively affordable cost of application, and TCM is therefore conceived as a possibility to treat PRRS under the current circumstance that there is a lack of safe and effective approaches. Here, we constructed a knowledge graph containing common biomedical data from humans and Sus Scrofaas well as information from thousands of TCMs. Subsequently, we validated the effectiveness of the Sus Scrofaknowledge graph by the t-SNE algorithm and selected the optimal model (i.e., transR) from six typical models, namely, transE, transR, DistMult, ComplEx, RESCAL and RotatE, according to five indicators, namely, MRR, MR, HITS@1, HITS@3 and HITS@10. Based on embedding vectors trained by the optimal model, anti-PRRSV TCMs were predicted by two paths, namely, VHC-Herb and VHPC-Herb, and potential anti-PRRSV TCMs were identified by retrieving the HERB database according to the pharmacological properties corresponding to symptoms of PRRS. Ultimately, Dan Shen's ( Salvia miltiorrhiza Bunge) capacity to resist PRRSV infection was validated by a cell experiment in which the inhibition rate of PRRSV exceeded 90% when the concentrations of Dan Shen extract were 0.004, 0.008, 0.016 and 0.032 mg/mL. In summary, this is the first report on the Sus Scrofaknowledge graph including TCM information, and our study reflects the important application values of deep learning on graphs in the swine industry as well as providing accessible TCM resources for PRRS.

African swine fever (ASF) is a highly contagious disease of domestic and wild pigs caused by African swine fever virus (ASFV). The mortality rate associated with ASF is remarkably high, almost approaching 100%. Since the introduction of ASF into China in 2018, its rapid spread has caused marked economic losses in the country’s swine industry. To date, there are no safe and effective commercial vaccines or antiviral drugs against ASF; thus, there is an urgent need to develop novel prevention and control strategies. Traditional Chinese medicine (TCM), which comprises various herbs that are abundant in various potential functional components, holds great promise for the prevention and control of ASF. Here, we provide a comprehensive review of the advancements in TCM and the effects of its compound formulas against ASF, including the antiviral abilities, immunoregulatory activities, and practical application of these formulas for the prevention and control of ASF. We specifically examined the potential and constraints of natural product-derived extracts and TCM formulas in combating ASFV. This review aims to offer insights and ideas for the holistic management and containment of ASF.

African swine fever (ASF), caused by the ASF virus (ASFV), is an acute, severe, and highly contagious infectious disease in domestic pigs and wild boars. Domestic pigs infected with a virulent ASFV strain can have morbidity and mortality rates of up to 100%. The epidemic of ASF has caused serious economic losses to the global pig industry. Currently, there is no safe and effective vaccine or specific drug for treating ASF. Therefore, ASFV still poses a great threat to pig factories. ASFV is a double-stranded DNA virus with a complex icosahedral multilayer structure. The ASFV genome contains 150-170 open reading frames (ORFs) that encode 150-200 proteins. Some ASFV-encoded proteins are involved in virus invasion, genome replication, DNA repair, and virion formation. Some ASFV proteins execute immunomodulatory functions by regulating the host antiviral innate immune response. Accumulating studies have shown that the immunomodulatory functions of ASFV genes are closely related to the virulence and pathogenicity of ASFV isolates. This review summarizes the research advances on ASFV immune evasion mechanisms in African swine fever patients and provides new insights for developing attenuated live vaccine candidates to prevent and control ASF.

The prevalence of bacterial digestive diseases in plateau animals has caused considerable losses to the Tibetan livestock industry. Therefore, this study aimed to isolate safe lactic acid bacteria (LAB) with beneficial probiotic properties to protect yaks from intestinal diseases. After 16S rDNA matching, four strains of Lactobacillus fermentum(A4), Pediococcus pentosaceus(A3.4 and A1.2), and Pediococcus acidilactici(B1.9) were isolated from the intestinal tissues and content of healthy yaks. The results indicated that A4 was more tolerant to bile salt (0.3%), while A3.4 had better stability in an acidic (pH=3.0) environment. The results of the antibacterial activity test suggested that the isolates inhibited most pathogenic bacteria by up to 20%, except for A3.4, which inhibited Pasteurellaand Staphylococcus aureusby more than 20%. Moreover, the results of the antioxidant test demonstrated that A4 and A3.4 had potent antioxidant activity. In addition, the drug sensitivity test revealed that the isolates were susceptible to commonly used antibiotics. In terms of safety, the isolates promoted growth, enhanced intestinal development, and protected the intestinal barrier without causing any adverse effects. In conclusion, LAB isolated from yak intestinal contents are potential probiotics with excellent antibacterial properties.

Bordetella bronchiseptica( Bb) is recognized as a leading cause of respiratory diseases in dogs and cats. However, epidemiological data on Bbin dogs and cats in China are still limited, and there is no commercially available vaccine. Live vaccines containing Bbthat are widely used abroad are generally effective but can establish latency and potentially reactivate to cause illness in some immunodeficient vaccinated recipients, raising safety concerns. In this study, 34 canine-derived and two feline-derived Bbstrains were isolated from 1809 canine and 113 feline nasopharyngeal swab samples collected from eight provinces in China from 2021 to 2023. The PCR results showed that the percentage of positive Bbwas 22.94% (441/1922), and more than 90% of the Bbisolates had four virulence factor-encoding genes (VFGs), namely, fhaB, prn, betAand dnt. All the isolated strains displayed a multidrug-resistant phenotype. The virulence of 10 Bbstrains isolated from dogs with respiratory symptoms was tested in mice, and we found that eight isolates were highly virulent. Furthermore, the eight Bbisolates with high virulence were inactivated and intramuscularly injected into mice, and three Bbstrains (WH1218, WH1203 and WH1224) with the best protective efficacy were selected. Dogs immunized with these three strains exhibited strong protection against challenge with the Bbfield strain WH1218. Ultimately, the WH1218 strain with the greatest protection in dogs was selected as the vaccine candidate. Dogs and cats that received a vaccine containing 10⁹ CFU of the inactivated WH1218 strain showed complete protection against challenge with the Bbfield strain WH1218. This study revealed that Bbis an important pathogen that causes respiratory diseases in domestic dogs and cats in China, and all the isolates exhibited multidrug resistance. The present work contributes to the current understanding of the prevalence, antimicrobial resistance, and virulence genes of Bbin domestic dogs and cats. Additionally, our results suggest that the WH1218 strain is a promising candidate safe and efficacious inactivated Bbvaccine.

Bovine coronavirus (BCoV) poses a significant threat to the global cattle industry, causing both respiratory and gastrointestinal infections in cattle populations. This necessitates the development of efficacious vaccines. While several inactivated and live BCoV vaccines exist, they are predominantly limited to calves. The immunization of adult cattle is imperative for BCoV infection control, as it curtails viral transmission to calves and ameliorates the impact of enteric and respiratory ailments across all age groups within the herd. This study presents an in silico methodology for devising a multiepitope vaccine targeting BCoV. The spike glycoprotein (S) and nucleocapsid (N) proteins, which are integral elements of the BCoV structure, play pivotal roles in the viral infection cycle and immune response. We constructed a remarkably effective multiepitope vaccine candidate specifically designed to combat the BCoV population. Using immunoinformatics technology, B-cell and T-cell epitopes were predicted and linked together using linkers and adjuvants to efficiently trigger both cellular and humoral immune responses in cattle. The in silico construct was characterized, and assessment of its physicochemical properties revealed the formation of a stable vaccine construct. After 3D modeling of the vaccine construct, molecular docking revealed a stable interaction with the bovine receptor bTLR4. Moreover, the viability of the vaccine’s high expression and simple purification was demonstrated by codon optimization and in silico cloning expression into the pET28a (+) vector. By applying immunoinformatics approaches, researchers aim to better understand the immune response to bovine coronavirus, discover potential targets for intervention, and facilitate the development of diagnostic tools and vaccines to mitigate the impact of this virus on cattle health and the livestock industry. We anticipate that the design will be useful as a preventive treatment for BCoV sickness in cattle, opening the door for further laboratory studies.