Search Results (644)

Background/Objectives: Porcine circovirus type 2 (PCV2) infection causes porcine circovirus disease (PCVD), a global immunosuppressive disease in pigs. Its clinical manifestations include post-weaning multisystemic wasting syndrome (PMWS) and porcine dermatitis and nephropathy syndrome (PDNS), which cause significant economic losses to the swine industry. The Cap protein, which is the major protective antigen of PCV2, can self-assemble to form virus-like particles (VLPs) in the insect baculovirus expression system. Few studies have compared the expression of Cap proteins in different baculovirus expression systems. Methods: In this study, we compared two commonly commercialized baculovirus construction systems with the Cap protein expression in various insect cells. Results: The results demonstrate that the flashBAC system expressed the Cap protein at higher levels than the Bac-to-Bac system. Notably, when expressing four copies of the Cap protein, the flashBAC system achieved the highest protein yield in High Five cells, where it reached 432 μg/mL at 5 days post-infection (dpi) with 27 °C cultivation. Animal experiments confirmed that the purified Cap protein effectively induced specific antibody production in mice and swine. Conclusions: This study provides critical data for optimizing the production of the PCV2 Cap protein, which is of great significance for reducing the production cost of PCV2 vaccines and improving the industrial production efficiency. Full article

Porcine circovirus type 3 (PCV3) has been detected in wild boars across many countries in Europe, Asia, and South America. However, data regarding the presence of porcine circoviruses in wild boars and ticks remain limited. In this study, we investigated the presence and genetic characteristics of PCV3 in wild boars and parasitizing ticks in Jiangsu, China. Samples, including whole blood, serum, tissues, feces, and oral fluids from wild boars, as well as ticks collected from 47 wild boars, were obtained between March 2021 and November 2022. PCR results indicated that 34.0% (16/47) of wild boars tested positive for PCV3, while ELISA detected 41.9% (18/43) seropositivity. RT-qPCR results showed that 7.2% (6/83) were positive for PCV3 in 83 analyzed tick samples, with all positive samples identified as Amblyomma testudinarium. The PCV3 genome obtained from wild boars was classified as PCV3a and was closely related to the strain identified in domestic pigs in Nanjing, Jiangsu Province. Collectively, these findings confirm the presence of PCV3 in wild boars in Jiangsu and suggest a possible link of PCV3 infection among domestic pigs, wild boars, and ticks, providing new insights into the transmission risk of PCV3 at wildlife–livestock–human interfaces and highlighting the genetic homology between strains from wild and domestic pigs. Full article

Wild boars are recognized reservoirs of numerous viral pathogens, posing a significant risk to domestic pig populations, particularly in areas with poor biosecurity. This study assessed the prevalence and co-infection patterns of porcine circovirus type 2 (PCV2), porcine parvovirus (PPV), porcine cytomegalovirus (PCMV), African swine fever virus (ASFV), classical swine fever virus (CSFV), and pseudorabies virus (PRV) in wild boars from western Serbia and the Republic of Srpska (Bosnia and Herzegovina). Sixty-six spleen samples from legally hunted wild boars were analyzed by qPCR. All animals were negative for ASFV, CSFV, and PRV. The cumulative prevalence of infection with at least one of the other three viruses was 86.4% (95% CI: 76.2–92.8%). PCMV was detected in 74.2% of samples, PCV2 in 50%, and PPV in 28.8%. Co-infections were common: 42.4% of animals were positive for two viruses, and 12.1% for all three. A statistically significant association was observed between triple co-infection and sex, with higher rates in males. Subadult wild boars showed the highest PCV2 + PCMV co-infection rate (p = 0.0547). These findings highlight the need to expand molecular surveillance, particularly for PCMV, in both wild and domestic pigs, especially in regions reliant on low-biosecurity backyard farming. Full article

Chicken anemia virus (CAV) and Eimeria tenella (E. tenella) are economically important pathogens of the poultry industry worldwide. However, the impact of dual infection of these two pathogens in chickens remains unclear. This study investigated the pathogenic effects of dual infection with CAV and E. tenella using two trials. In Trial A, chickens were infected at 21 days of age (D21) with either CAV and E. tenella simultaneously (C₂₁ + T₂₁), CAV alone (C_21a), E. tenella alone (T₂₁), or PBS as a negative control (NC). In Trial B, chickens received CAV at D21 followed by E. tenella at D28 (C₂₁ + T₂₈), CAV alone at D21 (C_21b), E. tenella alone at D28 (T₂₈), or PBS at D21 (NC). Assays of lesion scores (LS), oocysts per gram (OPG) of feces, packed cell volume (PCV), and thymus index (TI) were used to assess variations in pathogenicity. Both the C₂₁ + T₂₁ and C₂₁ + T₂₈ groups showed higher OPG than the group infected with E. tenella alone, with significantly elevated OPG in the secondary infection scenario and more severe lesions in the concurrent co-infection group (p < 0.05). Anemia, indicated by PCV < 27%, was observed in the C₂₁ + T₂₁ group at day 28 and in the C₂₁ + T₂₈ group at day 35, both of which had significantly lower PCV values than the group infected with CAV alone (p < 0.001). Thymus atrophy was most severe in C₂₁ + T₂₁ at 28 days old (p < 0.05; p < 0.01). In this study, preliminary observations suggested that concurrent and secondary infections with CAV and E. tenella showed variable trends that may indicate potential interactions; however, these exploratory findings require more systematic validation in older chickens. Full article

Background: Pneumococcal vaccination rates in the United States (US) remain suboptimal, especially for adults aged 19 to 64 with high-risk medical conditions. Community-pharmacy-based immunization services increase vaccine access, particularly in rural areas. This study describes the provision of pneumococcal immunization services, assesses the processes used to identify and confirm patient eligibility, and determines barriers to immunization services in rural community pharmacies. Methods: A cross-sectional survey was emailed to members of the Rural Research Alliance of Community Pharmacies, located in the southeastern US. The survey assessed which pneumococcal vaccines were offered, age groups, prescription requirements, and how patient eligibility was determined. In addition, participants were asked to rate a series of patient-related and organizational barriers to pneumococcal vaccination. Results: Ninety-four pharmacies completed the survey, with most (96.8%) offering pneumococcal vaccines, most commonly PCV20 (95.6%). Most pharmacies vaccinated patients upon request (98.9%) or when patients presented with a prescription (82.4%), but few proactively contacted patients to schedule the vaccination (17.6%). Pharmacists most often administered pneumococcal vaccines to patients aged 65 and older and used patient age and immunization information systems to identify eligible patients. The most common patient-related barrier was the patient’s belief that they do not need the vaccine. The most common organizational barriers were inadequate reimbursements for vaccine administration and vaccine products. Conclusions: Pneumococcal vaccinations are commonly offered in rural community pharmacies, which play an important role in immunization access. With recent guideline changes to the age-based recommendation, there is an opportunity to optimize strategies to increase vaccine uptake. Full article

Gastrointestinal (GI) parasites not only significantly impact goat health and productivity but can also affect human health due to the zoonotic potential of some species. This study investigates the prevalence of internal parasites within the tropical monsoon ecosystem of southern Thailand, focusing on both phenotypic and molecular characteristics of the parasites and identifying associated risk factors in caprine farming systems. A total of 276 meat goats from Nakhon Si Thammarat province were examined, indicating an overall GI parasite prevalence of 88.8% (245/276), with strongyles and Eimeria spp. identified as the dominant parasites. In addition, mixed parasitic infections were observed in 72.2% of cases, whereas single infections comprised 27.8%. Strongyle-positive fecal samples were cultured and genetically sequenced, revealing the presence of Haemonchus contortus, Trichostrongylus colubriformis, and Oesophagostomum asperum. For associated risk factors, gender and grazing with other herds significantly impacted overall GI parasitic infections, while the gender, breed, and packed cell volume (PCV) affected the strongyle infection. A correlation analysis revealed a substantial relationship between strongyle egg per gram (EPG) counts and clinical parameters, indicating that monitoring animals with low body condition scores (BCS) and high Faffa Malan Chart (FAMACHA) scores could be an effective strategy for controlling strongyle infections. These findings highlight the importance of continued research and effective farm management practices to address strongyle infections in meat goats, improving their health and agricultural productivity in tropical regions. Moreover, the detection of four zoonotic parasites (Giardia spp., H. contortus, T. colubriformis, and Fasciola spp.) indicates the necessity for the routine surveillance and monitoring of zoonotic parasites in goats to mitigate potential human health risks. Full article

Porcine circoviruses are significant pathogens that affect swine populations worldwide, with implications for animal health and productivity. While PCV2 is well-documented, particularly due to widespread vaccination programs, PCV3 is less understood, and its epidemiological impact is still under investigation. This study screened for PCV2 and PCV3 in pigs and wild boars across Portugal to assess their prevalence. Also, nucleotide sequence determination was performed to evaluate the genetic diversity of these viruses. Stool samples from 160 pigs belonging to different groups (quarantine, nursery, fattening and adult pigs), as well as organ samples from 120 hunted wild boars, were analyzed. Samples were collected from twelve of the eighteen mainland Portuguese districts with positive cases being detected in nine of them. Pigs had a lower prevalence of PCV2 (1.9%) than PCV3 (11.2%), but the opposite was true in wild boars (76.7% for PCV2 and 55.0% for PCV3). The lower PCV2 prevalence in pigs can be attributed to the PCV2 vaccination program implemented. Additionally, these viruses were significantly more prevalent in wild boars (90.8% were infected with at least one of the viruses) than in domestic pigs (only 12.5%). This significant difference highlights the impact of the controlled environment in pig farms on disease prevention in contrast to the higher exposure risks faced by wild boars in their natural habitat. Compared to a previous study from 2023, we observed a slight decrease in the percentage of positive cases for both PCV2 and PCV3. Phylogenetic analysis of sequences obtained by Sanger sequencing allowed us to conclude that the samples from domestic pigs belong to the PCV2a and PCV3c clades, in contrast to the PCV2-positive cases detected in domestic pigs in 2023 that were classified in the PCV2d genotype. Conversely, samples from wild boars belong to the PCV2d and PCV3a clades. These results reveal genotype differences between wild and domestic pigs and shifts from 2023 to 2024. Our findings provide some information about the circulation of these viruses and emphasize the importance of vaccination and continued monitoring for a deeper understanding of their epidemiology to mitigate potential risks to swine health and production. Full article

Background/Objectives: Porcine Circovirus Type 2 (PCV2) impairs pigs’ immune systems and increases susceptibility to co-infections, including Classical Swine Fever (CSF), a highly contagious disease listed by the World Organisation for Animal Health (WOAH) as notifiable. Therefore, swine operations in CSF-endemic regions are encouraged to immunize piglets with both PCV2 and CSFV vaccinations. Currently, there is no commercially available bivalent vaccine for PCV2/CSFV. Methods: In this study, a total of twenty 4-week-old SPF pigs were administered our formulated PCV2/CSFV bivalent subunit vaccine, containing soluble CSFV-E2 (50 µg) and PCV2-ORF2 (100 µg) antigens with a porcine-specific CpG adjuvant. After 4 weeks of vaccination, all pigs were evaluated for efficacy against PCV2 and CSFV. Results: Pigs were only immunized once and showed significantly increased neutralizing or ELISA antibody titers against both viruses four weeks post-vaccination. After viral challenges, vaccinated pigs displayed no clinical signs or lesions and had markedly reduced CSFV and PCV2 viral loads in the serum and tissues compared to controls. Conclusions: These results demonstrate that a single dose of the PCV2/CSFV bivalent subunit vaccine is safe and effective in young pigs, induces strong antibody responses, and suppresses viral replication, making it a promising tool for swine disease control and cost-effective vaccination strategies. Full article

This study investigates the complex interactions between environmental, genetic, and structural factors that influence two key parameters: the density of Phytophthora spp. propagules per gram of dry soil (NPSS) and the number of colonies (NC). Using advanced statistical approaches, we examined the combined effects of variables such as soil moisture, dry weight, temporal fluctuations, and rootstocks. The results show a significant linear relationship between NPSS and soil moisture, as well as a strong positive correlation between NPSS and NC. Genetic analyses reveal a predominant contribution of environmental factors to trait variability, with high phenotypic coefficient of variation (PCV) and low broad-sense heritability. Mixed models highlight the synergistic impact of soil moisture, NC, and dry soil weight on NPSS, as well as significant temporal effects. Mediation analysis confirms that soil moisture influences NPSS primarily through an indirect effect transmitted by NC, with a mediated proportion exceeding 94%. Finally, multivariate analysis reveals significant differences between rootstocks, with Citrus Volkameriana B2 28613 (R4) and Mandarin Sunki x P.T. B2 38581 (R7) standing out as the most performant. These results highlight the importance of an integrated management of environmental variables and rootstocks to optimize soil productivity and agronomic quality. The implications of this study provide a solid foundation for guiding genetic improvement and soil management strategies, balancing environmental constraints and the opportunities offered by targeted genetic selection. Full article

Since its emergence in China in 2018, African swine fever virus (ASFV) has posed a severe threat to the pig farming industry due to its high transmissibility and mortality rate. The clinical signs of ASFV infection often overlap with those caused by other swine viruses such as classical swine fever virus (CSFV), porcine reproductive and respiratory syndrome virus (PRRSV), pseudorabies virus (PRV), and porcine circovirus type 2 (PCV2), making timely and precise diagnosis a considerable challenge. To address this, we established a TaqMan-based multiplex real-time quantitative PCR (qPCR) assay capable of simultaneously detecting ASFV, CSFV, PRRSV, PRV, and PCV2. Specific primer-probe sets were developed targeting conserved genomic regions: the ASFV P72 gene, CSFV 5’UTR region, PRRSV ORF6, PCV2 cap gene, and PRV gB gene. After thorough optimization, the assay demonstrated robust analytical performance, exhibiting strong target specificity with no cross-detection of non-target pathogens. The detection threshold was determined to be 10 copies/μL per virus, indicating high assay sensitivity. Repeatability analysis revealed low variability, with intra- and inter-assay coefficient of variation values remaining below 2.3%. When applied to 95 clinical samples, the multiplex assay yielded results that were fully consistent with those obtained using commercially available singleplex qPCR kits. In conclusion, the multiplex TaqMan qPCR method developed in this study is characterized by high specificity, sensitivity, and reproducibility. It provides a reliable and efficient diagnostic tool for the simultaneous detection and differential diagnosis of ASFV and other clinically similar viral infections in swine, thereby offering robust technical support for swine disease surveillance and control. Full article

Background: A comparative analysis was conducted between two immunisation protocols using different amounts of protein extracts from adult Haemonchus contortus worms, purified by thiol-Sepharose chromatography (625 μg/animal vs. 200 μg/animal). These protocols involved either five or two inoculations of the immunogen, respectively. Methods: To evaluate the level of immunoprotection, animals were challenged with L3 of H. contortus two weeks after the last inoculation of the immunogen and humanely sacrificed at 8 weeks post-infection. Parasitological, biopathological, and serological parameters were monitored through the experiment. Parasite burden, abomasal-specific antibody responses, and histopathological changes were determined at the end of the trial. Results: The immunisation protocols resulted in similar reductions in cumulative faecal egg counts (60.5–64.9%) and the total worm burden (47.5–50%) compared to non-immunized (control) animals. Overall, these parasitological data showed an early recovery of the haematocrit (PCV) after challenge in the immunised groups relative to control. Similarly, levels of H. contortus-specific IgG and IgA antibodies increased in both the serum and gastric mucus of immunised groups. Conclusions: These findings represent a further step towards the potential application of this type of immunogen under field conditions, as protective responses (associated with a reduction in faecal egg output) were achieved using a simplified protocol, with lower immunogen doses and fewer inoculations required to induce immunoprotection, thereby mitigating the pathological effects of the parasite and reducing its ability to spread and infect susceptible hosts. Full article

Background and Aim: Pneumococcal pneumonia is a major cause of death globally, emphasizing the importance of vaccination, especially in low- and middle-income countries. In Iran, the 13-valent pneumococcal conjugate vaccine (PCV13) is available exclusively through private healthcare systems, resulting in a lack of studies on the prevalence of Streptococcus pneumoniae (S. pneumoniae) serotypes among vaccinated children. This research aimed to explore and compare the prevalence of nasopharyngeal pneumococcal carriage, serotype distribution, and antibiotic resistance patterns in healthy PCV13-vaccinated and -unvaccinated children. Methods: From August 2023 to November 2024, a multi-center, cross-sectional observational study was conducted in Tehran, Iran. This study included 204 nasopharyngeal samples collected from children aged from 18 to 59 months, involving both cases of children vaccinated with PCV13 and unvaccinated populations. S. pneumoniae was identified through a combination of culture methods and biochemical tests, confirmed by real-time PCR. Serotyping was achieved using cpsB sequencing, and the minimum inhibitory concentration method was employed to assess antibiotic resistance. Results: This study revealed similar S. pneumoniae carriage rates between PCV13-vaccinated and -unvaccinated Iranian children (20.6% vs. 21.6%). Serotypes 23F and 19F were prevalent in unvaccinated children, while 15B/15C was more prevalent in PCV13-vaccinated children. The included S. pneumoniae serotypes in PCV13 were detected more in the unvaccinated group. PCV13-vaccinated children exhibited no penicillin-resistant pneumococcal isolates, although four isolates were non-susceptible in unvaccinated children. Both groups showed substantial resistance to erythromycin and SXT. Previous respiratory infections, daycare attendance, residence in Tehran, and a history of antibiotic consumption increased the risk of pneumococcal carriage. Conclusions: PCV13 vaccination influences pneumococcal serotype distribution and antimicrobial susceptibility, although there was no significant difference regarding carriage rates between vaccinated and unvaccinated groups. These findings highlight the critical importance of vaccination in reducing invasive serotypes and antimicrobial resistance in children under five years old, emphasizing the importance of national PCV vaccination programs alongside continuous serotype surveillance. Full article

Pneumonia is a major issue that affects calves’ health and performance and causes numerous losses despite treatment. Investigating genetic and molecular differences, as well as immunological and antioxidant responses, in calves at risk for pneumonia was the aim of this study. A total of 225 calves were studied, including 180 Holstein calves with respiratory signs and 45 calves that were apparently healthy. Blood samples were collected for CBC, RNA extractions, and immunological and antioxidant analysis. In contrast to the control group, the pneumonic one showed a considerable (p < 0.05) increase in the expression levels of cytokines and antioxidant genes IL1α, IL-1β, IL-6, IFN-γ, TNF-α, and NOX4. In contrast, the values of IL10, PRDX6, ATG7, and NDUFS6 were in the opposite range. The pneumonic and healthy calves were found to differ in the nucleotide sequences of the genes under analysis. In pneumonic calves, a substantial (p ˂0.05) reduction was detected in RBCs, Hb count, PCV%, and lymphocytes count, and a notable (p ˂ 0.05) increase in WBCs and neutrophil count was correlated with healthy control calves. The findings of the serum profile showed that there was a meaningful (p ˂ 0.05) rise in the serum values of IL-1α, IL-1β, IL-6, TNF-α, IFN-γ, and MDA, with significant reductions in the SOD, GSH, TAC, and IL-10 in the pneumonic compared to the healthy calves. Our results provide valuable information about the nucleotide sequence, gene expression, and serum profile differences of putative indicators for pneumonia in calves. This could be applied in monitoring calves’ pneumonia through the discriminate breeding of naturally resistant animals. Full article

Background/Objectives: This study describes multiple trials demonstrating the safety and efficacy of a tri-valent vaccine against diseases caused by Porcine Circovirus Types 2a and 2d (PCV2a, PCV2d), Mycoplasma hyopneumoniae, and Lawsonia intracellularis. Methods: For each of the PCV2a and PCV2d onset of immunity (OOIs) and duration of immunity (DOI) studies, 25 pigs were vaccinated with a tri-valent vaccine and 25 with placebo. After dual challenge with PCV2a and porcine reproductive and respiratory virus (PRRSV) (OOI) or single challenge with PCV2d (OOI and DOI), respectively, viremia and lymphoid depletion data were collected. For each of the M. hyopneumoniae OOI and DOI studies, 35 to 70 pigs were vaccinated with the tri-valent vaccine and 35 to 70 with placebo. After M. hyopneumoniae challenge, the lungs were scored for disease. For the L. intracellularis OOI study, 40 to 50 pigs were vaccinated with the tri-valent and 40 to 50 with placebo. After L. intracellularis challenge, the intestines were scored for disease. All pigs were vaccinated at approximately 3 weeks of age, and all placebo vaccines were product matched. Results: Vaccinating pigs with a tri-valent vaccine reduced viremia and lymphoid depletion due to PCV2a and PCV2d, reduced lung lesions due to M. hyopneumoniae and reduced ileum and colonization scores due to L. intracellularis. Conclusions: The trials reported here demonstrated the safety and efficacy of the first ready-to-use PCV2, M. hyopneumoniae, and L. intracellularis vaccine for pigs. Full article

Background/Objectives: Porcine circovirus type 2d (PCV2d) is the predominant genotype associated with porcine circovirus-associated disease (PCVAD), leading to significant economic losses. In South Korea, current vaccine lot-release testing relies on a T/C-ratio-based guinea pig assay, which lacks scientific justification and methodological robustness. This study aimed to develop and validate a statistically defined in-house ELISA using rabbit-derived polyclonal antibodies against PCV2d for the standardized evaluation of immunogenicity. Methods: Polyclonal IgG was generated by immunizing a rabbit with inactivated PCV2d, and it was purified through Protein A chromatography. Guinea pigs (n = 18) were immunized with IMMUNIS^® DMVac, an inactivated PCV2d vaccine candidate developed by WOOGENE B&G, at different doses. In-house ELISA parameters were optimized (antigen coating, blocking agent, and substrate incubation), and analytical performance was evaluated by ROC, linearity, reproducibility, and specificity. Sera from guinea pigs and pigs were analyzed under validated conditions. Results: The optimal performance was achieved using 10⁵ genomic copies/mL of the antigen coating and a 5% BSA blocking agent. The assay showed strong diagnostic accuracy (AUC = 0.97), reproducibility (CVs < 5%), and linearity (R² = 0.9890). Specificity tests with PCV2a, PCV2b, and PRRSV showed minimal cross-reactivity (<7%). The cross-species comparison revealed a positive correlation (R² = 0.1815) and acceptable agreement (bias = −0.21) between guinea pig and porcine sera. The validated cut-off (S/P = 0.4) enabled accurate classification across both species and aligned well with commercial kits. Conclusions: The in-house ELISA offers a robust, reproducible, and scientifically validated platform for immunogenicity verification, supporting its application in Korea’s national lot-release system. Homologous competition assays with PCV2d are planned to further confirm antigen specificity. Full article