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: Aujeszky’s disease virus (ADV) infects a wide range of animals, including members of the Suidae family, i.e. domestic and wild pigs, as well as wild boar. Since wild boar are a potential ADV reservoir and a source of infection for domestic pigs, the aim of the study was to evaluate ADV antibody prevalence in the Polish wild boar population, during the years 2011 to 2014. Material and Methods: Wild boar blood samples were collected during three consecutive hunting seasons; i.e. 2011/2012, 2012/2013, and 2013/2014, and tested for ADV antibodies by ELISA. Results: ADV antibodies were detected in samples from all tested voivodships. The average seroprevalence reached 32.2%. Seroprevalence, over the examined hunting seasons, was 27.4% in 2011/2012, 32.4% in 2012/2013, and 35.5% in 2013/2014. The highest percentage of seroreagents was detected in four voivodships, situated along the western border of Poland, i.e. Zachodnio-Pomorskie (ZP), Lubuskie (LB), Dolnośląskie (DS), and Opolskie (OP). This area is positively correlated with the highest density of the wild boar population and the highest wild boar hunting bag. Conclusion: The results of this study confirm that the wild boar population may still pose a threat to domestic pigs, which is of special importance at the final stage of Aujeszky’s disease eradication programme in Poland.

Introduction: The genomes of nine H5 subtypes of low pathogenic avian influenza virus (LPAIV) strains identified in wild birds in Poland between 2010 and 2015 were sequenced, and their phylogenetic relationship was determined. Material and Methods: AIV genome segments were amplified by RT-PCR and the PCR products were sequenced using Sanger method. Phylogenetic trees were generated in MEGA6 software and digital genotyping approach was used to visualise the relationship between analysed strains and other AIVs. Results: High genetic diversity was found in the analysed strains as multiple subgroups were identified in phylogenetic trees. In the HA tree, Polish strains clustered in two distinct subclades. High diversity was found for PB2, PB1, PA and NP, since 5-8 sublineages could be distinguished. Each strain had a different gene constellation, although relationship of as much as six out of eight gene segments was observed between two isolates. A relationship with poultry isolates was found for at least one segment of each Polish strain. Conclusion: The genome configuration of tested strains indicates extensive reassortment, although the preference for specific gene constellation could be noticed. A significant relationship with isolates of poultry origin underlines the need for constant monitoring of the AIV gene pool circulating in the natural reservoir.

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: Data collection on the Salmonella occurrence is crucial in effective implementation of different actions or control programmes aiming to protect consumers’ health and to reduce the level of Salmonella prevalence in farm animals. The goal was to describe Salmonella serovar distribution along the food chain in Poland during 2010–2015 and to identify their epidemiological importance.Material and Methods: Slide agglutination according to White-Kauffmann-Le Minor scheme was used to identify Salmonella serovars of 6,928 isolates originating from animals, food, feeds, and fertilisers.Results: In total, 160 Salmonella serovars were identified. Differences in serovar distribution were observed depending on animal species. Among isolates from hens, S. Enteritidis and S. Infantis were the most prevalent. Serovar pattern in turkeys differed from those in hens, with S. Kentucky, S. Newport, S. Saintpaul being the most prevalent. Monophasic S. Typhimurium was predominant in pigs. Serovars found in food reflected those observed among livestock animals. Nine out of the ten most prevalent serovars in animals and humans were also found in organic fertilisers.Conclusion: Serotyping of large number of isolates from different sources is essential for insight on emerging serovars and trends of Salmonella occurrence. This may increase the value of epidemiological data and result in updating of Salmonella control programmes to target further epidemiologically important serovars in animals and better protection of consumers’ health.

Introduction: The objective was to evaluate the epizootic and epidemiological situation of Trichinella sp. infection in Poland between 2006 and 2015 against the dynamics of the wild boar population and its primary reservoir host.Material and Methods: Boar and porcine trichinosis epizootic analysis was based on General Veterinary Inspectorate data from RRW-6 bulletins. The epidemiological situation was evaluated on the basis of the data supplied by the Department of Epidemiology of the National Institute of Hygiene - National Institute of Public Health. The wild boar hunting harvest and population dynamics were estimated, as these animals remain the basic infection source for humans. Population size and harvest data were obtained from hunting statistics.Results: The study timeframe showed an almost 2.5-fold increase in Trichinella infection cases in wild boars but a significant decline in human cases. In the domestic pig, the incidence rate did not exceed 0.00037%. The highest infection risk exists in West Pomerania, Greater Poland, and Kuyavian-Pomeranian Provinces. Over the study period, the wild boar population increased more than 1.5-fold, while the hunting harvest more than tripled. During the last two seasons the total hunt surpassed 100% of the spring population.Conclusion: Wild boar management by increasing the hunting take of the annual population growth should limit that growth and decrease the take in the future. Thereby, over some years intra-species trichinosis spread should reduce, for a substantial safety gain for wild boar meat.

Introduction: The objective of the present research was to carry out a comparative assessment of copper, zinc, and selenium concentrations in the meat of edible land snails collected in Poland (Helix pomatia, Cornu aspersum maxima, and Cornu aspersum aspersum), as well as to determine the effect of preliminary processing of Roman snails (Helix pomatia) on the content of the aforementioned elements. Material and Methods: In the first stage, determinations were made on unprocessed snail meat. In the second stage, the study focused on Roman snails and consisted in an additional evaluation of frozen meat after full processing. Zinc and copper contents were determined by flame atomic absorption spectrometry and the selenium content was established by graphite furnace atomic absorption spectrometry. Results: The selenium content differed significantly among all three species. The copper content in Roman snails differed significantly from that in farmed snails. No significant difference in the zinc level was noted among the three snail species. The selenium content in raw and processed meat of Roman snails did not show any significant difference while the copper and zinc level was significantly higher in processed meat samples. Conclusion: The present research on the meat of edible snails showed different levels of selenium, copper, and zinc, depending on the species, collection site, and subjection to processing.

Introduction: The aim of this study was to assess the seroprevalence of swine influenza A virus (SIV) in Polish farrow-to-finish pig herds.Material and Methods: Serum samples collected from 5,952 pigs, from 145 farrow-to-finish herds were tested for the presence of antibodies against H1N1, H1N1pdm09, H1N2, and H3N2 SIV subtypes using haemagglutination inhibition (HI) test. Samples with HI titres equal or higher than 20 were considered positive.Results: HI antibodies to at least one of the analysed SIV subtypes were detected in 129 (89%) herds and in 2,263 (38%) serum samples. Antibodies to multiple SIV subtypes were detected in 104 (71.7%) herds and in 996 (16.7%) serum samples. Concerning the seroprevalence rate, according to age category, the highest prevalence of the antibodies was detected in weaners, with regard to the H1N1, H1N2, and H3N2, and in sows, with regard to the H1N1pdm09. The lowest seroprevalence for all evaluated SIV subtypes was detected in finishers.Conclusion: The study indicates that antibodies against single and multiple SIV subtypes are circulating in Polish farrow-to-finish herds and highlights the importance of conducting a molecular surveillance programme in future studies.

Introduction: The prevalence of arrhythmias in dogs and the influence of sex, breed, age, and body weight were analysed over a seven-year span. Material and Methods: In total, 1189 referrals for cardiological examination by electrocardiography were received at one academic centre in Poland between 2008 and 2014. The largest proportion of the examined dogs were cross-breeds with body weight below 25 kg (n = 153, 12.87%), followed by German Shepherds (n = 122, 10.26%), Labrador Retrievers (n = 68, 5.72%), Yorkshire Terriers (n = 63, 5.3%), and Boxers (n = 60, 5.05%). Retrospective analysis was made of 1201 standing or right recumbent electrocardiograms without pharmacological sedation. The prevalence of arrhythmias was examined in terms of sex, age, body weight, and breed of the dogs. Results: A total of 630 (52.46%) electrocardiograms showed no signs of arrhythmia, but 96 (7.99%) and 475 (39.55%) pointed to physiological and pathological arrhythmias respectively. The most commonly diagnosed type was atrial fibrillation with 33.68% incidence, followed by ventricular arrhythmias (28%), sinus pauses (27.58%), supraventricular arrhythmias (24%), and atrioventricular blocks (22.95%). Pathological arrhythmias were most commonly found in male dogs and in German Shepherds. Conclusions: Atrial fibrillation predominated, followed by premature ventricular complexes. Male dogs were generally more prone to heart rhythm disturbances.

Introduction: The aim of this study was to evaluate the dependence between ejaculate traits, sperm morphology, and ejaculate volume in Duroc boars. Material and Methods: The analysis involved 121 ejaculates collected from 12 Duroc boars kept in three artificial insemination centres located in central Poland. Ejaculates were collected manually at one-month intervals, over a period of 10 months. At least 10 ejaculates were collected from each boar. The material was divided by ejaculate volume and each ejaculate was assigned to one of three volume groups: 160 mL and lower, 161–200 mL, and 201 mL and higher. The ejaculates were assessed to identify the basic physical traits and determine the incidence of morphological abnormalities in the spermatozoa, specifying major and minor abnormalities. Furthermore, the morphological structure indices for the spermatozoa were also calculated. Results: In large-volume ejaculates, spermatozoa were more elongated in shape, their heads were more elongated and had the largest flagella. With an increase in the ejaculate volume, sperm concentration in the ejaculate decreased. Moreover, while the total number of sperm in the ejaculate increased, the number of insemination doses obtained from a single ejaculate were higher. Conclusion: The volume of ejaculate has little impact on the occurrence of morphological abnormalities and the size of sperm cells. Ejaculate volume is important for the shape of the sperm cells.