Introduction: Due to their immunostimulatory properties TLR ligands are used prophylactically to protect against a variety of viral and bacterial pathogens in mammals. Knowledge of the molecular and functional aspects of TLRs is essential for a better understanding of the immune system and resistance to diseases in birds. For that reason, this study attempted to determine the impact of TLR21 stimulation by its synthetic ligand (CpG ODN, class B) on the chicken immune system. Material and Methods: Sixty embryonated chicken eggs were randomly allocated into three groups (control and two experimental groups). On day 18 of embryonic development, chickens in one experimental group were administered in ovo a low dose of CpG ODN and the birds of the second experimental group were given a high dose of the ligand. Spleens were collected at 1, 2, 5, and 10 days post-hatching (dph) for analysis of IFN-α, IFN-β, IFN-γ, IL-6, and IL-10 expression using qRT-PCR. Results: Significant differences were observed in mRNA expression levels of all the measured cytokines associated with the modulation and regulation of the immune response at different time points. Conclusion: The obtained data clearly demonstrate that immune response induction takes place after in ovo administration of class B CpG ODN, and that the ligand has the ability to induce cytokine responses in neonatal chicken spleen.

Introduction: A novel to Europe Schmallenberg virus (SBV) causes clinical disease manifested by reproduction disorders in farm ruminants. In free-living ruminants, SBV antibodies as well as the virus were detected. Recent studies also revealed SBV antibodies in wild boars. The study investigates SBV antibodies occurring in wild boars in Poland at the peak of recent virus epidemics in the country.Material and Methods: Samples collected from 203 wild boars culled during the 2012/2013 and 2013/2014 hunting season were serologically tested using multi-species cELISA. Attempted neutralisation tests failed due to poor serum quality. RT-PCR was implemented in seropositive and doubtful animals.Results: Two samples collected from wild boar in the winter of 2013 gave a positive result in ELISA, while another two from the 2012/2013 hunting season were doubtful. No SBV RNA was detected in spleen and liver tissues.Conclusion: Low SBV seroprevalence in wild boars, despite high incidence of SBV infections occurring simultaneously in wild ruminants, suggests that boars are unlikely to be a significant reservoir of the virus in the sylvatic environment in Poland.

Introduction: Vascular cell adhesion molecule 1 (VCAM-1) is a member of Ig superfamily. The aim of this study was to prepare highly specific polyclonal antibodies against bovine VCAM-1 and to evaluate the expression of VCAM-1 in the mammary lymph nodes of cows with subclinical mastitis.Material and Methods: The VCAM-1 gene was cloned from bovine Peyer’s patches and inserted into the pGEX-4T-1 and pET-28a vectors. The recombinant plasmids pGEX-4T-1/VCAM-1 and pET-28a/VCAM-1 were transferred into Escherichia coli BL21 and the recombinant strains were induced by isopropyl-D-thiogalactoside to produce fusion proteins tagged with polyhistidine (His) and glutathione S-transferase (GST), respectively. The expressed fusion proteins His-VCAM-1 and GST-VCAM-1 were identified by SDS-PAGE and Western blot. His-VCAM-1 protein was used as an antigen to immunise Wistar rats and polyclonal antibody serum against VCAM-1 was obtained.Results: The serum titre tested by indirect ELISA was 128,000 using GST-VCAM-1 as the well coating antigen. Western blots indicated that the antibody recognised recombinant VCAM-1 protein as well as endogenous VCAM-1. In addition, using qPCR and Western blot, VCAM-1 mRNA and protein expression levels were measured in dairy cows with subclinical mastitis. It was demonstrated that VCAM-1 levels in the mammary lymph nodes of the cows were significantly higher than those from healthy controls (P < 0.05).Conclusion: These results are to our knowledge the first report that VCAM-1 expression in the mammary lymph nodes is elevated in dairy cows with subclinical mastitis.

Introduction: The toxinotyping and antimicrobial susceptibility of Clostridium perfringens strains isolated from processed chicken meat were determined. Material and Methods: Two hundred processed chicken meat samples from luncheon meats, nuggets, burgers, and sausages were screened for Clostridium perfringens by multiplex PCR assay for the presence of alpha (cpa), beta (cpb), epsilon (etx), iota (ia), and enterotoxin toxin (cpe) genes. The C. perfringens isolates were examined in vitro against eight antibiotics (streptomycin, amoxicillin, ampicillin, ciprofloxacin, lincomycin, cefotaxime, rifampicin, and trimethoprim-sulfamethoxazole) Results: An overall of 32 C. perfringens strains (16%) were isolated from 200 processed chicken meat samples tested. The prevalence of C. perfringens was significantly dependent on the type of toxin genes detected (P = 0.0), being the highest in sausages (32%), followed by luncheon meats (24%), burgers (6%), and nuggets (2%). C. perfringens type A was the most frequently present toxinotype (24/32; 75%), followed by type D (21.9 %) and type E (3.1%). Of the 32 C. perfringens strains tested, only 9 (28%) were enterotoxin gene carriers, with most representing type A (n = 6). C. perfringens strains differed in their resistance/susceptibility to commonly used antibiotics. Most of the strains tested were sensitive to ampicillin (97%) and amoxicillin (94%), with 100% of the strains being resistant to streptomycin and lincomycin. It is noteworthy that the nine isolates with enterotoxigenic potential had a higher resistance than the non-enterotoxigenic ones. Conclusion: The considerably high C. perfringens isolation rates from processed chicken meat samples and resistance to some of the commonly used antibiotics indicate a potential public health risk. Recent information about the isolation of enterotoxigenic C. perfringens type E from chicken sausage has been reported.

Introduction: The aim of this study was to evaluate the effect of lipoprotein fraction isolated from ostrich egg yolk (LPFo) on the metabolic activity of boar spermatozoa following liquid semen storage in different extenders and temperatures. Material and Methods: Boar ejaculates were extended in Androhep, Beltsville thawing solution (BTS), and Martín-Rillo and Alias (MR-A) without (control) or with the addition of LPFo and stored for three days at either 5°C or 16°C. The analysed sperm parameters included total motility (TMOT), plasma membrane integrity (PMI), mitochondrial membrane potential (MMP), oxygen consumption, and adenosine triphosphate (ATP) production. Results: The sperm metabolic activity seemed to be higher in the LPFo-based extenders following storage for three days, irrespective of the storage temperature. Compared with the LPFo-free extenders, significantly higher (P < 0.05) sperm PMI and MMP were observed in BTS and MR-A extenders supplemented with LPFo during storage for three days at 5°C. Spermatozoa stored in the BTS-LPFo extender exhibited higher (P < 0.05) TMOT and oxygen consumption, whereas higher (P < 0.05) PMI was observed in spermatozoa stored in Androhep-LPFo and MR-A-LPFo for three days at 16°C. No significant differences (P > 0.05) in ATP content were observed between the LPFo-free and LPFo-based extenders during storage. Conclusions: Supplementation of LPFo to semen extenders had varying effects on the metabolic activity of boar spermatozoa stored at different temperatures. It can be suggested that the interactions of various components of the extenders and seminal plasma with LPFo exert beneficial effects on the sperm metabolic activity during liquid storage of boar semen.

Introduction: Pregnancy is a physiological state in which the immune system undergoes certain changes. On the one hand, by depleting cell defence mechanisms, it favours development and maintenance of the pregnancy. At the same time cells of the immune system ensure resistance to many risk factors, including infectious agents.Material and Methods: The study was carried out on 24 Polish Konik breed mares which were divided into two equal groups. The first group (group I) included mares living in the reserve. The second group (group II) comprised mares maintained under conventional conditions in the stables. The blood samples were collected for the first time in the perinatal period, i.e. 2 weeks before parturition (trial 0), then within the first 24 h after delivery, and then on 7ᵗʰ and 21ˢᵗ day after foaling. Flow cytometric analysis of lymphocyte expressing TCD4+, TCD8+, CD2+, and MHC class II antigens was performed.Results: Before the delivery, in group I there was a significantly higher CD4:CD8 ratio compared to group II (P ≤0.05). Similarly, significantly increased CD4:CD8 ratio in group I was noted within 24 h after parturition (P ≤0.001) and it was also observed on 7ᵗʰ day (P ≤0.03) and 21ˢᵗ day after foaling (P ≤0.02). In the first 24 h after parturition, a significant decline of lymphocytes CD8+ (P ≤0.02) was noted. No significant differences in terms of lymphocytes CD2+ and CD3+ were observed. Expression of MHC-II molecules before and after the parturition was higher in group I compared to group II; however, the difference between the groups was not significant.Conclusion: The results obtained indicate that mares living in the reserve display higher activity of cell defence mechanisms.

Tenderness is the most important characteristic of meat, determining consumer approval. There are numerous methods of its improvement, although of diverse effectiveness. addition of vitamin D₃ to the feed for a short period before slaughter (7–10 days) is one of the natural ways to enhance the tenderness. Vitamin D₃ is responsible for Ca²⁺ mobilisation in serum and increase in activity of proteolytic enzymes belonging to calpains, which results in significant improvement of beef tenderness and reduction of ageing time. The use of vitamin D₃ is an application tool determining tenderness improvement of beef with substantial reduction in processing costs. Moreover, shorter post mortem ageing process will exceed the retail display time, which will consequently reduce losses due to unsold meat being returned from shops to the manufacturers. Based on the results of studies conducted over the last 15 years, this paper presents the possibility and the effects of the use of vitamin D₃ to improve beef tenderness.

Introduction: Studies of anabolic hormone residues in the tissues of slaughter animals have been carried out in Poland for more than 25 years. During the period of 2011 to 2015, a total of 35 387 samples from different animal species were tested in the National Residue Control Programme for the presence of residues of compounds that cause hormonal effects, as listed in Annex 1 of Directive 96/23/EC. Material and Methods: The research was conducted in the National Reference Laboratory and eight regional laboratories in departments of veterinary hygiene located throughout the country. Urine, muscle tissue, serum, kidney fat, and drinking water were the targeted matrices. Test methods based on instrumental techniques such as gas and liquid chromatography coupled with mass spectrometry were applied, as well as enzyme-linked immunosorbent assays (ELISA). Results: The concentration of detected hormones exceeded the decision limits in 30 samples, the consequence of which was 41 non-compliances with current applicable criteria. The hormones found present pseudo-endogenous (nortestosterone and boldenone) only, while synthetic hormones were not identified. Conclusion: The non-compliant findings constitute a small percentage (0.085%) of the five-year analysis compilation. On this basis the related food produced in Poland can be accepted as safe for human consumption with regard to the hormone residues tested.

Introduction: There are many veterinary products containing β-lactam antibiotics which are used for mastitis treatment in cows. The aim of the study was to determine whether mastitis could have any effect on amoxicillin (AMX) or penicillin G procaine (PEN) withdrawal period from milk, in the context of current maximum residue limits established by the European Commission. Material and Methods: The study was conducted on 17 dairy Black and White cows with clinical mastitis during the lactation period. The first group (n = 8) received 200 mg of amoxicillin (AMX), whereas the second group (n = 9) received 200,000 IU/mg of penicillin G procaine (PEN) by intramammary administration. For the measurement of AMX and PEN concentrations in milk, the liquid chromatography tandem mass spectrometry method was applied. Pharmacokinetic calculations were performed using Phoenix WinNonlin 6.4 software. Results: The determined AMX and PEN half-life values in the mammary gland suggest that the drug withdrawal is at a level of 99.9% within 81 h (≈3.5 days) and 116 h (≈5 days) after administration of AMX and PEN, respectively. The present research indicates that, at 60 h after administration, the average PEN concentration in the milk from cows with clinical signs of mastitis may still reach 4.96 g/kg and that of AMX can even be 6.92 g/kg. Conclusion: The results obtained confirm that, in mastitis cases, a 72-h withdrawal period is sufficient for elimination of AMX to a lower level than the established maximum residue limit (MRL) values. However, in the case of PEN, at 69 h after administration, the drug concentration may be close to that of the determined MRL.

Introduction: Chronic gastritis is a common diagnosis in dogs with signs of chronic vomiting. However, there is no data concerning endoscopic and histopathological agreement in dogs with chronic gastritis. Thus, a question should be raised whether taking gastroduodenal biopsies in dogs with chronic gastritis is necessary or not. Consequently, the purpose of the study was to compare the endoscopic and histopathological agreement in dogs with chronic gastritis. Material and Methods: A total of 22 non-pregnant client-owned dogs with the signs of chronic gastritis were enrolled in this prospective study. Procedures including clinical examination, blood analysis, and diagnostic imaging were performed before anaesthesia. Biopsies obtained from gastroduodenal sites were histopathologically evaluated. A total of 110 gastroduodenal samples were examined. Results: Sixtyeight samples had abnormal histopathology and endoscopy while 11 showed normal histopathological and endoscopic evidence. Conclusion: The obtained data demonstrated that it is not necessary to take extra gastroduodenal biopsies in dogs with evidence of endoscopic gastroduodenitis. We also believe that further prospective studies, including cost and time effectiveness and more specific comparison between endoscopic appearance and histopathology, are necessary to make final recommendations regarding the need of using both procedures for definitive diagnosis.