rss_2.0Journal of Veterinary Research FeedSciendo RSS Feed for Journal of Veterinary Research of Veterinary Research Feed of canine parvovirus occurrence in cats with clinical signs of feline panleukopenia in Slovakia – pilot study<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p>Feline panleukopenia is a contagious viral disease caused by the feline panleukopenia virus (FPV). A closely related pathogen is canine parvovirus (CPV), and amino acid substitutions in this virus allow it to acquire a feline host range. In feline hosts, the disease induced by CPV manifests with similar symptoms to those caused by FPV or milder ones, leading to its underdiagnosis. The aim of this study was to determine the presence of CPV type 2 (CPV-2) in cats with clinical symptoms of panleukopenia and to assess the use of commercial CPV antigen tests for the clinical diagnosis of FPV.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>Samples from 59 cats from central Slovakia were included in the study. Rectal swabs were collected and clinically tested for parvovirus infection using a commercial antigen test. Antigen-positive samples were confirmed by PCR targeting the viral <italic>VP2</italic> gene. The sequences of the PCR products were established with the Sanger method.</p> </sec> <sec> <title style='display:none'>Results</title> <p>Of 59 samples, 23 were revealed to be positive for parvovirus infection by both antigen and PCR test (38.9%). Analysis with the National Center for Biotechnology Information BLASTn application showed 99.78–100% pairwise identity with FPV. The mortality rate of parvovirus-infected cats included in this study was 8.69% (2/23).</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>Although feline disease with CPV-2 was not confirmed, the CPV antigen test was able to detect FPV infection.</p> </sec> </abstract>ARTICLEtrue evaluation of dogs’ exposure to benzophenones through hair sample analysis<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p>Benzophenones (BPs) are used in various branches of industry as ultraviolet radiation filters, but they pollute the natural environment, penetrate living organisms, and disrupt endocrine balance. Knowledge of the exposure of domestic animals to these substances is extremely scant. The aim of the study was to investigate long-term exposure of companion dogs to BPs and relate this to environmental factors.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>Hair samples taken from 50 dogs and 50 bitches from under 2 to over 10 years old were analysed for BP content with liquid chromatography–tandem mass spectrometry.</p> </sec> <sec> <title style='display:none'>Results</title> <p>The results revealed that dogs are most often exposed to 2-hydroxy-4-methoxybenzophenone (BP-3) and 4-dihydroxybenzophenone (BP-1). Concentration levels of BP-3 above the method quantification limit (MQL) were noted in 100% of the samples and fluctuated from 4.75 ng/g to 1,765 ng/g. In turn, concentration levels of BP-1 above the MQL were noted in 37% of the samples and ranged from &lt;0.50 ng/g to 666 ng/g. Various factors (such as the use of hygiene and care products and the dog’s diet) were found to affect BP concentration levels. Higher levels of BP-3 were observed in castrated/spayed animals and in animals that required veterinary intervention more often.</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>The results obtained show that the analysis of hair samples may be a useful matrix for biomonitoring BPs in dogs, and that these substances may be toxic to them.</p> </sec> </abstract>ARTICLEtrue of maceration treatment on ovarian follicular development, serum oestradiol, uterine growth and vascularisation in female albino rats<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p><italic>Curcuma longa</italic> is a well-known medicinal plant with various health benefits. This study was designed to evaluate the administration of Indonesian <italic>C. longa</italic> maceration for its effect on promoting growth and development of the ovary and uterus before mating in female albino rats.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>A total of 15 female Sprague Dawley rats in their dioestrous phase were assigned into three different groups: the Control group (mineral water); the Cur-Low group (mineral water with 1% <italic>C. longa</italic> maceration) and the Cur-High group (mineral water with 5% <italic>C. longa</italic> maceration). The treatments were given for 20 days. Serum concentrations of follicle-stimulating hormone, oestradiol and progesterone were determined. After the sacrifice of the rats, ovary and uterine relative weight, uterine cornua diameter and length, uterine gland diameter (by histology), the number of primary, secondary, tertiary, and Graafian follicles, the number of corpora lutea and vascular endothelial growth factor (VEGF) expression in the ovary were measured. Uterine vascularisation was also evaluated.</p> </sec> <sec> <title style='display:none'>Results</title> <p>Administration of <italic>C. longa</italic> maceration significantly improved the relative weights of the uterus and ovary; uterine cornua diameter, length and vascularisation; uterine gland diameter; and expression of VEGF in the ovary. It also increased the number of tertiary follicles and corpora lutea, albeit not significantly. Follicle-stimulating hormone serum concentrations were lower in the administered rats.</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>Oestradiol and progesterone levels rose with <italic>C. longa</italic> maceration treatment. The maceration improved the reproductive organs of unmated rats and had potential to optimise the uterine environment for supporting pregnancy in order to produce high-quality offspring.</p> </sec> </abstract>ARTICLEtrue characterisation of virus-like particles originating from native and mutated VP60 of rabbit haemorrhagic disease virus 2 and European brown hare syndrome virus<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p>Since lagoviruses cannot be cultivated <italic>in vitro</italic>, using expression systems is an alternative and promising way of producing diagnostic viral antigens. It opens up their use as active immunogens for vaccine production.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>Virus-like particles (VLPs) were produced in a baculovirus expression system in <italic>Spodoptera frugiperda</italic> 9 (Sf9) insect cells based on wild-type and mutated variants of the virus capsid VP60 protein from a Polish strain of European brown hare syndrome virus (EBHSV) and wild-type and mutated versions of this protein from a Polish strain of rabbit haemorrhagic disease virus 2 (RHDV2). The mutations were the substitution of an arginylglycylaspartic acid (Arg-Gly-Asp/RGD) motif in the P2 subdomain and, in the S or P2 domain, the substitution of three lysines. The VLPs were purified with sucrose gradient ultracentrifugation.</p> </sec> <sec> <title style='display:none'>Results</title> <p>Protein production was confirmed by Western blot analysis using rabbit or hare sera and ELISA tests with different types of monoclonal antibody. The haemagglutination properties of some VLPs were also evaluated. Electron microscopy of wild-type EBHSV, wild-type RHDV2 and the four VP60 variants produced in this experiment revealed the formation of characteristic VLP structures.</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>For the first time, mutated VLPs of RHDV2 with an RGD motif in the VP60 sequence were obtained, which could potentially be used to deliver cargo to eukaryotic cells. Virus-like particles based on the VP60 proteins of EBHSV and RHDV with a three-lysine substitution in the S or P2 domains were also obtained. Potential exists for VLPs of EBHSV and RHDV2 as vaccine candidates.</p> </sec> </abstract>ARTICLEtrue analysis of the trypanosomatid parasite in honey bees () in Poland<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p><italic>Lotmaria passim</italic> (<italic>L. passim</italic>) is a single-celled flagellate which colonises the bee gastrointestinal tract and is highly prevalent in honey bees. This parasite is associated with colony losses. Honey bee (<italic>Apis mellifera</italic>) colonies were sampled from five apiaries in the north-eastern part of Poland for the phylogenetic analysis of <italic>L. passim</italic>.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>Each apiary consisted of approximately 60 bee colonies, of which 20 were randomly selected. Samples of 60 differently aged worker bees were collected from each colony and pooled. A total of 100 bee colonies from five apiaries were examined. Protozoa of the Trypanosomatidae family were identified by PCR. <italic>L. passim</italic> was detected in 47 (47%) of the samples. The 18S ribosomal (r) RNA amplicons of <italic>L. passim</italic> were sequenced by a commercial service. Their sequences were analysed with BLASTN and noted to be compatible with the GenBank sequences of this region of the organism’s genome. A sequence analysis was performed using the BioEdit Sequence Alignment Editor and Clustal W software.</p> </sec> <sec> <title style='display:none'>Results</title> <p>The amplicon sequences of <italic>L. passim</italic> were 100% homologous with the sequences deposited in GenBank under accession numbers KM066243.1., KJ684964.1 and KM980181.1.</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>This is the first study to perform a phylogenetic analysis of <italic>L. passim</italic> in Polish honey bees. The analysis demonstrated high levels of genetic similarity between isolates of <italic>L. passim</italic> colonising apiaries in the north-eastern region of Poland.</p> </sec> </abstract>ARTICLEtrue and icariin can inhibit bovine viral diarrhoea virus replication by promoting type I interferon response<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p>Bovine viral diarrhoea virus (BVDV) can cause diarrhoea (BVD) in an animal herd, leading to heavy economic losses. There are limited drugs available for treating and controlling BVD. This research aims to investigate the antiviral and immunoregulatory effects of two traditional Chinese herb extracts against BVDV infection. The extracts are matrine and icariin, which have been proved to have immunostimulant and antiviral effects.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>A cell counting kit-8 assay was used to analyse the toxicity of matrine and icariin to Madin–Darby bovine kidney (MDBK) cells. The model of MDBK cells infected with BVDV was utilised to uncover the antiviral mechanism of matrine and icariin, which along with their immunoregulatory ability was evaluated by quantitative reverse-transcription PCR and ELISA.</p> </sec> <sec> <title style='display:none'>Results</title> <p>The results showed that matrine and icariin can significantly inhibit the gene expression level of the BVDV 5′ untranslated region through various pathways. Both matrine and icariin can statistically upregulate the gene expression level of interferon alpha, interferon beta (IFN-β), toll-like receptor 3, retinoic acid–inducible gene I and interferon regulatory factor 3, and raise the concentration of IFN-β after BVDV infection.</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>This study proves that both matrine and icariin have inhibitory effects on BVDV replication by activating IFN production and the IFN signalling pathway. The finding is promising and should open up the possibility of larger-scale <italic>in vitro</italic> research followed by <italic>in vivo</italic> experiments evaluating matrine and icariin as therapeutic agents in BVD cases.</p> </sec> </abstract>ARTICLEtrue tropism and genetic traits of carp oedema virus isolates to enhance detection strategies<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p>Carp oedema virus (CEV) is a relatively understudied poxvirus. It exhibits an affinity for gill and skin epithelial cells. Investigations were conducted into selected aspects of CEV biology, with a focus on determining cell and tissue tropism of CEV, acquiring gene sequences and updating CEV tests in fish tissues.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>A total of 238 common carp tissue samples from nine aquaculture farms were analysed. The study evaluated the efficacy of intermediate detection of CEV by real-time PCR and <italic>in situ</italic> hybridisation. The genes encoding protein P4a were sequenced, analysed and aligned in a phylogenetic tree using a molecular evolution model.</p> </sec> <sec> <title style='display:none'>Results</title> <p><italic>In situ</italic> hybridisation revealed the necessity to validate the Centre for Environment, Fisheries and Aquaculture Science protocols for sampling for CEV detection and to use the tissues for which the virus has the highest tropism, namely the skin and kidneys, rather than solely the gills. The level of genetic variability was determined, and it was shown that CEV mutates systematically. The creation of two distinct phylogenetic clades confirms certain strains’ description as Polish isolates.</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>Determining the localisation of CEV genetic material in organs and tissues is pivotal for shaping the World Organisation for Animal Health guidelines. The utility of molecular diagnostics has been demonstrated in the skin and kidney of carp, in addition to the gills, impelling their inclusion in diagnostic protocols. The clusters identified in the phylogenetic tree offer valuable insights for developing the current PCR primers. The prevalence of CEV infection in aquaculture, juxtaposed with its notably lower detection in wild fish, underscores the significance of mandatory molecular diagnostic testing for CEV in carp farming.</p> </sec> </abstract>ARTICLEtrue of the season-dependent component in the evaluation of morphological and biochemical blood parameters in Shetland ponies of both sexes during exercise<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p>Determination of morphological and biochemical blood indices facilitates assessment of the health and welfare of horses, their nutrient demand, the effects of training already undertaken, and the horses’ suitability for exercise. Identification of the season-dependent components and the effects of sex and exercise on changes in frequently referenced haematological and biochemical parameters was the main goal of the current study.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>The blood morphology of 21 healthy adult Shetland ponies (11 mares and 10 stallions) aged 6.5 ± 1.4 years from the central Pomeranian region in Poland was analysed. Blood samples were taken once per season for one year.</p> </sec> <sec> <title style='display:none'>Results</title> <p>No statistically significant season-dependent differences were found in the blood morphology parameters in either mares or stallions before or after exercise. Beta-coefficient results revealed the strength and type of the relationship of red blood cell distribution width (RDW) and granulocyte count (GRA) with the season, of red blood cell count (RBC), haematocrit, mean corpuscular volume and mean platelet volume with the sex, and of RDW, white blood cell count, GRA and RBC with the exercise factor. Biomarkers demonstrating the relationship between aerobic and anaerobic levels of energy metabolism in the blood did not show any sex dependency in regression analysis.</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>The sex-independence of energy metabolism biomarkers may indicate the universality of these parameters. Both seasonality itself and its combination with the exercise factor took part in the formation of effective adaptive reactions for maintenance of morphological blood indices in the ponies during exercise.</p> </sec> </abstract>ARTICLEtrue of and in collected from dogs in eastern Poland<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p><italic>Ixodes ricinus</italic> ticks are an important vector and reservoir of pathogenic microorganisms causing dangerous infectious diseases in humans and animals. The presence of ticks in urban greenery is a particularly important public health concern due to the potential for humans and companion animals to be exposed to tick-borne diseases there. The study assessed the prevalence of <italic>Borrelia burgdorferi</italic> and <italic>Anaplasma phagocytophilum</italic> infection in <italic>I. ricinus</italic> ticks feeding on dogs.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>The study consisted in analyses of <italic>I. ricinus</italic> ticks collected in 2018–2020 from owned and stray dogs in the north-eastern part of Lubelskie province (eastern Poland). An AmpliSens PCR kit was used for qualitative detection and differentiation of tick-borne infections.</p> </sec> <sec> <title style='display:none'>Results</title> <p>Infections of <italic>B. burgdorferi</italic> and <italic>A. phagocytophilum</italic> were detected in 10.9% and 12.9% of the examined ticks, respectively. One tick (0.7%) was co-infected by both pathogens. Infection with <italic>B. burgdorferi</italic> was significantly more highly prevalent in ticks collected from the owned dogs than from the strays (18.7% and 2.8%, respectively), whereas the prevalence of <italic>A. phagocytophilum</italic> was similar in both groups (12.0% and 13.9%, respectively).</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>The co-infection observed in the study suggests the possibility of simultaneous infection by both pathogens from a single tick bite. The presence of pathogens in ticks collected from dogs is a factor in assessing infection risk not only to companion animals but also to their owners, who are in close contact with their dogs and visit the same green areas recreationally.</p> </sec> </abstract>ARTICLEtrue expression of porcine transient receptor potential mucolipin protein channels and their differential responses to porcine reproductive and respiratory syndrome virus infection<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p>Porcine reproductive and respiratory syndrome virus (PRRSV) infection results in a serious disease, posing a huge economic threat to the global swine industry. The transient receptor potential mucolipin proteins (TRPMLs) have been shown to be strongly associated with virus infection and other physiological processes in humans, but their tissue distribution and responses to PRRSV in pigs remain unknown.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>Quantitative reverse-transcription PCR analysis was undertaken to determine the optimal primer for TRPML expression detection and for quantifying that expression individually in different pig tissue samples. Meat Animal Research Center 145 (MARC-145) monkey kidney cells and the TRPML-specific activator mucolipin synthetic agonist 1 (ML-SA1) were used to reveal the relationship between TRPML and PRRSV-2 infection.</p> </sec> <sec> <title style='display:none'>Results</title> <p>The best primers for each TRPML gene used in a fluorescence-based quantitative method were identified and TRPML1 was found to be highly expressed in the kidneys and liver of pigs, while TRPML2 and TRPML3 were observed to be primarily expressed in the kidney and spleen tissues. The expression of TRPML2 was upregulated with the rise in PRRSV-2 infection titre but not the expression of TRPML1 or TRPML3, and ML-SA1 inhibited PRRSV-2 in a dose-dependent manner.</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>Our research revealed the gene expression of TRPMLs in pigs and identified that TRPML channels may act as key host factors against PRRSV infection, which could lead to new targets for the prevention and treatment of pig infectious diseases.</p> </sec> </abstract>ARTICLEtrue secretion in stem cells of cattle infected with bovine leukaemia virus<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p>Bovine leukaemia virus (BLV) is a Deltaretrovirus responsible for enzootic bovine leukosis, the most common neoplastic disease of cattle. It deregulates the immune system, favouring secondary infections and changes in the blood and lymphatic tissues. Blood homeostasis depends on functional haematopoietic stem cells (HSCs). Bone marrow is populated by these cells, which express CD34<sup>+</sup> and CD35<sup>+</sup> surface antigens and produce and release cytokines involved in the maintenance of haematopoiesis. The aim of the study was determination of the profile of cytokine production by CD34<sup>+</sup> stem cells of cattle naturally infected with BLV.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>The HSCs were generated from the blood and lymphoid organs of cows infected with BLV and healthy control cows with immunomagnetic separation and anti-CD34<sup>+</sup> monoclonal antibodies. Isolated CD34<sup>+</sup> cells were cultivated for two weeks with interleukin (IL)-4 and granulocyte-macrophage colony-stimulating factor. The levels of IL-6, IL-10, IL-12p40, IL-12p70, interferon gamma (IFN-γ) and tumour necrosis factor alpha (TNF-α) were determined in culture fluid by flow cytometry.</p> </sec> <sec> <title style='display:none'>Results</title> <p>The expression of IL-6, IL-12p70 and TNF-α in blood HSCs was higher in BLV<sup>+</sup> cows than in the control animals. In bone marrow HSCs of infected cows, IL-12, TNF-α and IFN-γ were more concentrated, but in these cows’ spleen HSCs only expression of IL-10 was elevated. In HSCs isolated from the lymph nodes of leukaemic cows, only TNF-α secretion was lower than in control cows, the other cytokines being more potently secreted.</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>Infection with BLV caused statistically significant differences in cytokine expression by HSC CD34<sup>+</sup> cells.</p> </sec> </abstract>ARTICLEtrue survey and genetic diversity of sp. infesting domestic poultry in northeastern Thailand<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p>Haemosporidian parasites are prevalent worldwide and can cause economic losses in poultry production. These parasites are arousing interest in Thailand and are found in many avian species. There is insufficient information on the genetic diversity of these alveolates from the largest families – Plasmodidae, Haemoprotidae and Leucocytozoidae – specifically parasitising ducks, turkeys, and geese.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>Blood samples from 116 backyard poultry (60 ducks, 36 turkeys and 20 geese) in northeastern Thailand were investigated for <italic>Plasmodium</italic> spp., <italic>Haemoproteus</italic> spp. and <italic>Leucocytozoon</italic> spp. infections using microscopic examination and molecular approaches.</p> </sec> <sec> <title style='display:none'>Results</title> <p>A total of 37/116 birds (31.9%) had confirmed <italic>Plasmodium</italic> infections. The prevalence was 69.4% (25/36) in turkeys, 18.3% (11/60) in ducks, and 5.0% (1/20) in geese. Of these 37 positives, 86.5% were <italic>Plasmodium</italic> sp., 10.8% were <italic>P. gallinaceum</italic> and 2.7% were <italic>P. juxtanucleare</italic>. Sequence analysis based on the cytochrome <italic>b</italic> gene identified seven lineages, of which two were new lineages in backyard poultry.</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>This is the first report on the prevalence of haemosporidian parasites in backyard poultry in northeastern Thailand. The results provide important data for better understanding the molecular epidemiology of haemosporidian parasites infection in poultry in this region, which will be helpful in controlling these blood parasites.</p> </sec> </abstract>ARTICLEtrue supplementation as an alternative to antibiotics in broiler chickens<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p>The broiler chicken digestive tract microbiome maintains the bird’s immunity. Its composition has been shown to be important not only for the immune system but also for the gastrointestinal function and productivity of broiler chickens. If the microbiome is populated by supplementation with <italic>Lactobacillus, Pediococcus</italic> and <italic>Saccharomyces</italic> spp. – microorganisms with probiotic properties and alternatives to antibiotics – the immune system is stimulated. The use of probiotic supplements in the broiler production cycle can boost bird immunity and prevent adenovirus infection. The resilience of broiler chickens in different feeding schemes including supplementation with these microorganisms was assessed.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>Four groups of Ross 308 chickens vaccinated on the standard scheme were investigated over 42 days. Group P received probiotics, prebiotics and vitamins; group AO received antibiotics; group P&amp;AO received probiotics, prebiotics, vitamins and antibiotics; and the control group C received none of these. The birds’ immunocompetence against common viral poultry pathogens and their immune response to an experimental challenge with a field strain of infectious bronchitis was evaluated by ELISA and production parameters were recorded.</p> </sec> <sec> <title style='display:none'>Results</title> <p>Mortality was only observed in the control group and was 10%. All birds from the P, P&amp;AO and AO groups responded to the challenge as would be expected of appropriately immunised chickens.</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>The obtained results indicated that supplementation with synbiotic products and vitamins can enhance broiler chicken immunity and result in better production parameters.</p> </sec> </abstract>ARTICLEtrue determination of sulfonamides, trimethoprim, amoxicillin and tylosin in medicated feed by high performance liquid chromatography with mass spectrometry<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p>The article presents a rapid and simple analytical procedure for determination of four sulfonamides (sulfadiazine, sulfamerazine, sulfamethazine and sulfamethoxazole), trimethoprim, tylosin and amoxicillin in animal medicated feed.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>Eighteen medicated feed samples were analysed for active substances. The analytical protocol used a mixture of acetonitrile and 0.05 M phosphoric buffer, pH 4.5 for the extraction of seven antibacterial substances. After extraction, the samples were diluted in Milli-Q water and analysed by liquid chromatography with mass spectrometry. The developed procedure was subjected to validation in terms of linearity, selectivity, limits of quantification and determination, repeatability, reproducibility and uncertainty.</p> </sec> <sec> <title style='display:none'>Results</title> <p>The validation of the method was carried out in accordance with the criteria set out in Commission Implementing Regulation (EU) 2021/808 and ICH guidelines. This method provided average recoveries of 90.8 to 104.5% with coefficients of variation for repeatability and reproducibility in the ranges of 3.2–6.9% and 5.2–8.3%, respectively for all analysed antibacterial substances. The limit of detection and limit of quantification for all seven analytes ranged from 5.4 mg/kg to 48.3 mg/kg and from 10.4 mg/kg to 119.3 mg/kg, respectively. The uncertainty of the method depending on the compound varied from 14.0% to 24.0%. The validated method was successfully applied to the 18 medicated feeds.</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>The developed method can be successfully used to routinely control the content and homogeneity of seven antibacterial substances in medicated feed.</p> </sec> </abstract>ARTICLEtrue first confirmed cases of pigeon rotavirus A (RVA) infection in domestic pigeons in Poland<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p>Although the presence of rotaviruses in pigeon samples has been reported since the 1980s, its importance as an aetiological agent of the “classical” young pigeon disease (YPD) was not proven until 2020, when the Henle–Koch postulates were confirmed for pigeon-type rotavirus A (RVA) genotype G18P(17).</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>From 2011 to 2020, archived liver samples from 117 pigeons submitted by 74 individual lofts were tested for the presence of pigeon-type RVA using a VP6-specific RT-qPCR test. For four positive racing pigeons, a more detailed necropsy and histopathological analysis was performed.</p> </sec> <sec> <title style='display:none'>Results</title> <p>Indicators of an acute RVA infection were found in 24 out of 117 (20.5%) samples tested, the earliest in 2014. Necropsies of the four selected RVA-positive pigeons showed changes mainly in the liver, spleen and kidneys similar to those described by other researchers. The histopathological examination revealed mainly hyperaemia and necrosis in the liver, as well as mononuclear cell infiltrates in these organs.</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>Pigeon-type RVA is also a cause of YPD in Poland and is a serious challenge for racing pigeon breeders and veterinarians, especially during the training and flights of young pigeons.</p> </sec> </abstract>ARTICLEtrue first complete genome sequence and genetic evolution analysis of bovine norovirus in Xinjiang, China<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p>Viruses are among the main pathogens causing diarrhoea in calves. The current study found that bovine norovirus (BNoV) is one of the principal viruses causing diarrhoea in calves in Xinjiang, China.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>A total of 974 calf faecal samples from six regions in Xinjiang were tested for BNoV using reverse-transcriptase PCR. The genomic characteristics of BNoV and the genetic evolution of the VP1 gene, protein three-dimensional structure characteristics and amino acid variation were analysed using bioinformatics methods.</p> </sec> <sec> <title style='display:none'>Results</title> <p>Epidemiological survey results showed that the infection rate of BNoV was 19.82%, and all samples tested positive in five regions. The results of the genetic evolution analysis showed that BNoV strains from Tacheng of northern Xinjiang and Kashgar of southern Xinjiang both belonged to the GIII.2 genotype of BNoV but were not on the same cluster of evolutionary branches. Additionally, the amino acid variation of the VP1 protein was not observed to significantly affect its spatial structure.</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>This study is the first to report the genetic characteristics of the BNoV complete genome sequence in Xinjiang and provides a scientific basis for BNoV vaccine development and pathogenesis research.</p> </sec> </abstract>ARTICLEtrue of herpesvirus in fish<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p>Herpesviruses are common agents in animals of the aquatic environment. They infect many species of fish but only lead to disease in one or two species. Nevertheless, infected fish without clinical symptoms can actively transfer infectious agents to disease-susceptible species. The aim of the study was to identify and prove the natural presence of different herpesviruses.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>Koi, Nile tilapia, grass carp, goldfish and crucian carp were infected with a herpesvirus isolate 99% identical to goldfish herpesvirus (GHV) or cyprinid herpesvirus 2 (CyHV-2) obtained from crucian carp. Before and after infection, samples were collected non-lethally at different time points from all five fish species to identify and evaluate the replication of viruses naturally infecting the fish as well as the CyHV-2 experimentally infecting them. Gill swabs and separated leukocytes were subjected to PCR and the results compared.</p> </sec> <sec> <title style='display:none'>Results</title> <p>These samples yielded DNA of koi herpesvirus (KHV, also referred to as CyHV-3), GHV and a new herpesvirus. While Asian-lineage CyHV-3 DNA was detected in samples from crucian carp and goldfish, CyHV-2 DNA was found in samples from koi and tilapia. A new, hitherto unknown herpesvirus was identified in samples from grass carp, and was confirmed by nested PCR and sequence analysis. The survival rates were 5% for grass carp, 30% for tilapia, 55% for crucian carp, 70% for koi and 100% for goldfish at 20 days post infection. Evolutionary analyses were conducted and five clusters were visible: CyHV-1 (carp pox virus), CyHV-2 with sequences from koi and tilapia, CyHV-3 with sequences from crucian carp and goldfish, probable CyHV-4 from sichel and a newly discovered herpesvirus – CyHV-5 – from grass carp.</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>The results obtained with the molecular tools as well as from the animal experiment demonstrated the pluripotency of aquatic herpesviruses to infect different fish species with and without visible clinical signs or mortality.</p> </sec> </abstract>ARTICLEtrue resistance of biovar isolates from chickens<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p><italic>Gallibacterium anatis</italic> is an opportunistic bacteria inducing a range of clinical signs in poultry. <italic>Gallibacterium anatis</italic> strains show multidrug resistance to antibacterial substances. The purpose of this study was to examine the susceptibility of <italic>G. anatis</italic> biovar <italic>haemolytica</italic> isolates collected from the respiratory, reproduction and gastrointestinal tracts of chickens to different antibiotics from various classes.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p><italic>Gallibacterium anatis</italic> biovar <italic>haemolytica</italic> was identified in tracheal swab and gastrointestinal and reproductive tract tissue samples from Polish layer and broiler chicken flocks. Twenty six isolates with β-haemolysis capability, each from a different flock, obtained from the respiratory (n = 8), reproductive (n = 10) and gastrointestinal (n = 8) tracts were selected and identified by matrix-assisted laser desorption/ionisation–time-of-flight mass spectrometry after culturing. A PCR method targeting the 16S genes was used for verification of isolates. The isolates’ susceptibility to 20 antimicrobials was evaluated using the disc diffusion method for 8 drugs and the dilution method for the other 12. In addition, they were tested for the presence of the <italic>Gtx</italic>A, <italic>gyr</italic>B and <italic>flf</italic>A virulence genes and <italic>bla</italic>ROB, <italic>aph</italic>A, <italic>tet</italic>B and <italic>tet</italic>H antibiotic resistance genes by PCR.</p> </sec> <sec> <title style='display:none'>Results</title> <p>The most prevalent antibiotic resistance was to tilmicosin, tylosin and quinupristin/dalfopristin (all 100%), erythromycin (96.2%), tetracycline (96.2%), linezolid (92.3%) and teicoplanin (92.3%). Universal susceptibility was to only one antibiotic, chloramphenicol. Statistically significant differences were found between the resistance of gastrointestinal tract strains and that of strains from other tracts to daptomycin, gentamicin, ciprofloxacin and colistin. The <italic>Gtx</italic>A and <italic>gyr</italic>B genes were detected in 100% of isolates and <italic>flf</italic>A in 19.2%. The isolates most frequently contained <italic>tet</italic>B and less frequently <italic>tet</italic>H and <italic>aph</italic>A, and did not contain <italic>bla</italic>ROB.</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>Most <italic>G. anatis</italic> biovar <italic>haemolytica</italic> isolates were resistant to many classes of antibiotics. Therefore, it is necessary and important to be vigilant for the occurrence of these bacteria and thorough in their diagnosis.</p> </sec> </abstract>ARTICLEtrue activity of monocyte-derived macrophages after stimulation with platelet-rich and platelet-poor concentrates. Study on an ovine model of insertion of a tibial implant coated with silicon-doped diamond-like carbon<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p>Macrophages are crucial immune cells that play a role in tissue repair and can exhibit pro- or anti-inflammatory behaviour based on environmental stimulation. Their functional phenotype can be affected by platelet-derived products as determined by those products’ composition. When the inflammatory response caused by implantation is excessive, it can lead to rejection of the implant. Therefore, a thorough evaluation of implant haemocompatibility is necessary to minimise undesirable consequences.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>In an <italic>in vitro</italic> study, monocyte-derived macrophages (MDMs) were obtained from the whole blood of sheep after a silicon-doped diamond-like carbon–coated implant insertion. These MDMs were then exposed to autologous platelet-derived products for functional marker analysis.</p> </sec> <sec> <title style='display:none'>Results</title> <p>Platelet-poor plasma (PPP) and pure platelet-rich plasma (P-PRP) stimulation increased arginase-1 activity, while leukocyte-rich PRP stimulation produced a mixed response involving higher O<sub>2</sub><sup>−</sup> (6.49 ± 2.43 nM <italic>vs</italic> non-stimulated 3.51 ± 1.23 nM, P-value &lt; 0.05) and NO (3.28 ± 1.38 μM <italic>vs</italic> non-stimulated 2.55 ± 0.32μM, P-value &lt; 0.05) generation.</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>Using PPP and P-PRP stimulation in post-implantation procedures may contribute to the polarisation of macrophages towards the M2-like pro-resolving phenotype, thereby accelerating wound healing. This would also prevent implant degradation due to an excessive inflammatory process.</p> </sec> </abstract>ARTICLEtrue analysis of skin lesions of cod from the southern part of the Baltic Sea<abstract> <title style='display:none'>Abstract</title> <sec> <title style='display:none'>Introduction</title> <p>Since the middle of the 1980s, severe skin disorders have been observed in Baltic cod (<italic>Gadus morhua</italic>) each year. Available data on the spectrum of bacteria isolated from the clinical cases being limited, and evaluation of the microbial background of fish skin lesions being useful, a bacteriological examination has been undertaken.</p> </sec> <sec> <title style='display:none'>Material and Methods</title> <p>A total of 1,381 cod were caught during two voyages of the Baltica research vessel in the Polish exclusive economic zone of the southern Baltic Sea. After an examination which found lesions in 164 of the fish, a microbiological analysis was performed to isolate bacteria from them. The collected strains were phenotyped and genotyped, and their antimicrobial resistance was analysed by minimum inhibitory concentration (MIC) techniques.</p> </sec> <sec> <title style='display:none'>Results</title> <p>Bacteriological examinations provided 850 isolates. The dominant microorganisms were mesophilic <italic>Aeromonas</italic> spp., <italic>Pseudomonas</italic> spp. and <italic>Shewanella baltica</italic>. Opportunistic bacteria potentially hazardous to human health were also isolated, <italic>e.g</italic>. <italic>Alcaligenes faecalis</italic>, <italic>Staphylococcus epidermidis</italic>, <italic>Stenotrophomonas maltophilia</italic> and <italic>Vibrio</italic> sp. The MIC analysis determined the highest number of bacteria to resist sulphamethoxazole and amoxicillin and clavulanic acid.</p> </sec> <sec> <title style='display:none'>Conclusion</title> <p>Most of the collected bacteria were opportunistic pathogens for fish, widespread in the aquatic environment, and potentially threatening to humans.</p> </sec> </abstract>ARTICLEtrue