Like RNA viruses in general, coronaviruses (CoV) exhibit high mutation rates which, in combination with their strong tendency to recombine, enable them to overcome the host species barrier and adapt to new hosts. It is currently known that six CoV are able to infect pigs. Four of them belong to the genus Alphacoronavirus [transmissible gastroenteritis coronavirus (TEGV), porcine respiratory coronavirus (PRCV), porcine epidemic diarrhea virus (PEDV), swine acute diarrhea syndrome coronavirus (SADS-CoV)], one of them to the genus Betacoronavirus [porcine hemagglutinating encephalomyelitis virus (PHEV)] and the last one to the genus Deltacoronavirus (PDCoV). PHEV was one of the first identified swine CoV and is still widespread, causing subclinical infections in pigs in several countries. PRCV, a spike deletion mutant of TGEV associated with respiratory tract infection, appeared in the 1980s. PRCV is considered non-pathogenic since its infection course is mild or subclinical. Since its appearance, pig populations have become immune to both PRCV and TGEV, leading to a significant reduction in the clinical and economic importance of TGEV. TGEV, PEDV and PDCoV are enteropathogenic CoV and cause clinically indistinguishable acute gastroenteritis in all age groups of pigs. PDCoV and SADS-CoV have emerged in 2014 (US) and in 2017 (China), respectively. Rapid diagnosis is crucial for controlling CoV infections and preventing them from spreading. Since vaccines are available only for some porcine CoV, prevention should focus mainly on a high level of biosecurity . In view of the diversity of CoV and the potential risk factors associated with zoonotic emergence, updating the knowledge concerning this area is essential.

Background Coronaviruses (CoVs) have long been known to cause infection in domestic and free-living birds and mammals including humans. The zoonotic origin of SARS-CoV-2 and the biological properties of CoVs, including ability to cross interspecies barriers, enable its emergence in populations of various animals, including companion animals (cats, dogs, rabbits) an area requiring further study. To date, several cases of cats and dogs positive for SARS-CoV-2 and/or specific antibodies have been described. The aim of our cross-sectional retrospective study is to determine seroprevalence of SARS-CoV-2 in domestic dog, cat and rabbit population during recent COVID-19 pandemic in Poland. Results In total, serum samples from 279 cats and 343 dogs and 29 rabbits were used in the study. The seroprevalence of SARS-CoV-2 in cats and dogs reached 1.79% (95% CI: 0.77 – 4.13) and 1.17% (95% CI 0.45 – 2.96), respectively (p ≥ 0.05). Anti- SARS-CoV-2 antibodies were detected in 5 cats (mean S/P% 106 ± 48.23) and 4 dogs (mean S/P% 78.5 ± 16.58). All 29 samples from rabbits were negative for SARS-CoV-2 antibodies. No significant gender or age differences in seroprevalence in dogs and cats (p ≥ 0.05) were found. None of the animals with anti-SARS-CoV-2 antibodies displayed respiratory or gastrointestinal signs at the time of sampling. Conclusions Our results confirmed previous findings that SARS-CoV-2 infections in companion animals occurs but are not frequent. Future serological testing of large pet population may provide a comprehensive picture of disease dynamics in companion animals.

Background: Simultaneous viral infections exhibit the phenomenon of viral interference, but understanding of the effect of one virus on another is limited. Objective: Evaluate and compare clinical characteristics, immune and acute phase response, viral shedding and viral load in pigs singly and doubly inoculated with swine influenza A virus (swIAV) and porcine reproductive and respiratory syndrome virus (PRRSV). Animals: Fifty-four 7-week-old piglets. Methods: Clinical status and gross lung lesions were scored. Titration of swIAV was carried out in Madin-Darby canine kidney cells. The PRRSV RNA was quantified using a commercial qPCR kit. Antibodies were detected by hemagglutination inhibition assay and commercial ELISA. A lymphocyte proliferation assay was used to measure antigen-specific T-cell responses. Acute phase proteins were determined using ELISA. Results: No differences were found between mean clinical scores, swIAV and PRRSV shedding, and magnitude of the humoral and T-cell response between single-inoculated and dual-inoculated groups. Concentrations of C-reactive protein and haptoglobin increased in PRRSV-inoculated and coinoculated groups, whereas serum amyloid A concentration was increased in groups inoculated or coinoculated with swIAV. Mean swIAV TCID 50 titers in the lungs did not differ significantly between coinoculated and swIAV single-inoculated pigs. A significantly higher mean copy number of PRRSV was found in the lungs of PRRSV only-inoculated pigs at 2 day postinoculation (DPI). From 4 DPI, no significant differences in PRRSV load were identified. Conclusions and Clinical Importance: Coinfection of pigs with swIAV and PRRSV did not potentiate clinical signs, lung lesions, immune response, and replication of the viruses in the respiratory tract.

Porcine circovirus type 2 (PCV2) plays a key role in PCV2-associated disease (PCVAD) etiology and has yielded significant losses in the pig husbandry in the last 20 years. However, the impact of two recently described species of porcine circoviruses, PCV3 and PCV4, on the pork industry remains unknown. The presence of PCV3 has been associated with several clinical presentations in pigs. Reproductive failure and multisystemic inflammation have been reported most consistently. The clinical symptoms, anatomopathological changes and interaction with other pathogens during PCV3 infection in pigs indicate that PCV3 might be pathogenic for these animals and can cause economic losses in the swine industry similar to PCV2, which makes PCV3 worth including in the differential list as a cause of clinical disorders in reproductive swine herds. Moreover, subsequent studies indicate interspecies transmission and worldwide spreading of PCV3. To date, research related to PCV3 and PCV4 vaccine design is at early stage, and numerous aspects regarding immune response and virus characteristics remain unknown.

Background Swine influenza A virus (IAV) and porcine reproductive and respiratory syndrome virus (PRRSV) are considered key viral pathogens involved in the porcine respiratory disease complex. Concerning the effect of one virus on another with respect to local immune response is still very limited. Determination of presence and quantity of cytokines in the lung tissue and its relation to the lung pathology can lead to a better understanding of the host inflammatory response and its influence on the lung pathology during single or multi-virus infection. The aim of the present study was to explore and compare the patterns of lung cytokine protein response in pigs after single or dual infection with swine IAV and/or PRRSV. Results Inoculation with IAV alone causes an increase in lung concentration of IFN-α, IFN-ɣ, TNF-α, IL-6, IL-8 and IL-10, especially at 2 and 4 DPI. In PRRSV group, beyond early IFN-α, IFN-ɣ, IL-6, IL-8 and IL-10 induction, elevated levels of cytokines at 10 and 21 DPI have been found. In IAV+PRRSV inoculated pigs the lung concentrations of all cytokines were higher than in control pigs. Conclusions Current results indicate that experimental infection of pigs with IAV or PRRSV alone and co-infection with both pathogens induce different kinetics of local cytokine response. Due to strong positive correlation between local TNF-α and IL-10 concentration and lung pathology, we hypothesize that these cytokines are involved in the induction of lung lesions during investigates infection. Nevertheless, no apparent increase in lung cytokine response was seen in pigs co-inoculated simultaneously with both pathogens compared to single inoculated groups. It may also explain no significant effect of co-infection on the lung pathology and pathogen load, compared to single infections. Strong correlation between local concentration of TNF-α, IFN-ɣ, IL-8 and SwH1N1 load in the lung, as well as TNF-α, IL-8 and PRRSV lung titres suggested that local replication of both viruses also influenced the local cytokine response during infection.

Prevention and control of African swine fever virus (ASFV) in Europe, Asia, and Africa seem to be extremely difficult in view of the ease with which it spreads, its high resistance to environmental conditions, and the many obstacles related to the introduction of effective specific immunoprophylaxis. Biological properties of ASFV indicate that the African swine fever (ASF) pandemic will continue to develop and that only the implementation of an effective and safe vaccine will ensure a reduction in the spread of ASFV. At present, vaccines against ASF are not available. The latest approaches to the ASFV vaccine’s design concentrate on the development of either modified live vaccines by targeted gene deletion from different isolates or subunit vaccines. The construction of an effective vaccine is hindered by the complex structure of the virus, the lack of an effective continuous cell line for the isolation and propagation of ASFV, unpredictable and stain-specific phenotypes after the genetic modification of ASFV, a risk of reversion to virulence, and our current inability to differentiate infected animals from vaccinated ones. Moreover, the design of vaccines intended for wild boars and oral administration is desirable. Despite several obstacles, the design of a safe and effective vaccine against ASFV seems to be achievable.

Due to increasing bacterial antibiotic resistance and the consumers’ tendency to choose organic products, cattle farmers are interested in alternative methods of calf diarrhoea treatment. This is a major challenge for veterinarians. Few methods of non-antibiotic treatment that bring satisfactory results have been reported in the related literature so far. In this article, the authors compare different non-antibiotic methods of diarrhoea prevention and treatment in calves. Among the alternatives discussed are herbs, probiotics, prebiotics and synbiotics, lactoferrin, and bacteriophages. It was found that the best results could be achieved through the use of pro-, pre- and synbiotics. However, the authors would like to point out that with the expansion of knowledge about the practical use of broad-scale bacteriophages, they could be the best alternative to antibiotics.

Hedgehogs are small insectivorous mammals common across Europe, Asia, and Africa. The increased encroachment of humans into hedgehog habitats has disrupted the human-animal-environment interface. With growing interest in the zoonotic diseases of wildlife species, more studies have been devoted to this subject in the last few years. These papers provide information about known and new emerging diseases. Here we review the current knowledge regarding bacterial, viral, protozoic, and mycotic pathogens with zoonotic potential and assess the importance of hedgehogs as their carriers. Both wild and pet hedgehogs were included in the review. Data from several countries and various hedgehog species were included. The study shows the importance of hedgehogs as carriers of zoonotic diseases and reservoirs of zoonotic pathogens in varied habitats.