Multi-class and multi-residue analyses are very complex procedures because of the physico-chemical properties of veterinary drug residues and other contaminants. The purpose of the study was to develop an analytical method for the sensitive determination of 69 analytes in bovine milk by liquid chromatography electrospray ionisation–tandem mass spectrometry. Antimicrobial, anabolic hormone, lactone, β-agonist, mycotoxin and pesticide residues were analysed in 120 raw milk samples from different dairy farms in North Macedonia. Stable isotopically labelled internal standards were used to facilitate effective quantification of the analytes. The linear regression coefficients were higher than 0.99, the limits of detection ranged from 0.0036 to 47.94 μg/L, and the limits of quantification ranged from 0.053 to 59.43 μg/L. The decision limit values ranged from 0.062 to 211.32 μg/L and the detection capability from 0.080 to 233.71 μg/L. Average recoveries of the analytes spiked in raw milk were in the range of 70.83% to 109%, intra-day coefficient of variation (CV) values from 2.41% to 22.29%, and inter-day CV values from 3.48% to 23.91%. The method was successfully applied in the testing of bovine milk samples. In five samples residues were detected. They were sulfadimethoxine (in two samples), enrofloxacin, tetracycline and oxytetracycline and were at concentrations below the EU maximum residue limit. The method is useful for routine testing for this group of chemical hazards in bovine milk.

Multi-class and multi-residue analyses are very complex procedures because of the physico-chemical properties of veterinary drug residues and other contaminants. The purpose of the study was to develop an analytical method for the sensitive determination of 69 analytes in bovine milk by liquid chromatography electrospray ionisation–tandem mass spectrometry.

It has been suggested that coagulase-negative staphylococci can serve as reservoirs of virulence genes for other bacteria. This study assessed the presence of such genes in selected isolates recovered from meat of the giant African snail (Achatina achatina). Virulence genes were detected using a polymerase chain reaction targeting specific primers. Two representative isolates were identified using 16S rRNA gene sequencing. The results showed that the staphylococcal enterotoxin A gene (sea) was present in five out of the eight isolates studied. The isolates expressed resistance mainly to three antibiotics: chloramphenicol, norfloxacin and cloxacillin in descending order of incidence. Most importantly, the Staphylococcus sciuri isolate NEDU 181, in addition to being resistant to the three aforementioned antibiotics, also harboured the sea gene. Our findings demonstrate, for the first time, the presence of toxigenic and antibiotic-resistant coagulase-negative Staphylococcus spp. in commercially-available fresh snail meat. With staphylococcal enterotoxin A known to survive cooking temperature, this presents a food safety concern.

It has been suggested that coagulase-negative staphylococci can serve as reservoirs of virulence genes for other bacteria. This study assessed the presence of such genes in selected isolates recovered from meat of the giant African snail (Achatina achatina).

Highly pathogenic avian influenza (HPAI) outbreaks caused by the Gs/Gd lineage of H5Nx viruses occur in Poland with increased frequency. The article provides an update on the HPAI situation in the 2020/2021 season and studies the possible factors that caused the exceptionally fast spread of the virus. Samples from poultry and wild birds delivered for HPAI diagnosis were tested by real-time RT-PCR and a representative number of detected viruses were submitted for partial or full-genome characterisation. Information yielded by veterinary inspection was used for descriptive analysis of the epidemiological situation. The scale of the epidemic in the 2020/2021 season was unprecedented in terms of duration (November 2020–August 2021), number of outbreaks in poultry (n = 357), wild bird events (n = 92) and total number of affected domestic birds (approximately ~14 million). The major drivers of the virus spread were the harsh winter conditions in February 2020 followed by the introduction of the virus to high-density poultry areas in March 2021. All tested viruses belonged to H5 clade 2.3.4.4b with significant intra-clade diversity and in some cases clearly distinguished clusters. The HPAI epidemic in 2020/2021 in Poland struck with unprecedented force. The conventional control measures may have limited effectiveness to break the transmission chain in areas with high concentrations of poultry.

Highly pathogenic avian influenza (HPAI) outbreaks caused by the Gs/Gd lineage of H5Nx viruses occur in Poland with increased frequency. The article provides an update on the HPAI situation in the 2020/2021 season and studies the possible factors that caused the exceptionally fast spread of the virus.

Dogs with chronic kidney disease (CKD) may have alterations in the glomerular filtration barrier, including podocyte loss. Detection of podocyte mRNA in urine could be useful for assessing podocyturia in dogs with kidney disease. The objective of this study was to evaluate the presence of nephrin mRNA (NPHS1) and podocin mRNA (NPHS2) in urine sediments of dogs with naturally occurring CKD and healthy dogs. Twenty-four dogs, 14 with CKD and 10 as healthy controls, underwent clinical evaluation. The dogs with CKD were divided into two groups, according to the International Renal Interest Society criteria: stage 1 or 2 CKD (n = 5) and stage 3 or 4 CKD (n = 9). Urine was collected by catheterisation or free catch and RNA isolation from the urine sediments was optimised using glycogen as a co-precipitant. Detection of NPHS1 and NPHS2 in the sediment samples was performed using quantitative real-time PCR. Both types of mRNA were detected in samples from all groups, but the percentages of detection were higher in the group of dogs with stage 1 or 2 CKD and lower in the group of dogs with stage 3 or 4 disease. Physiological podocyturia was observed in healthy dogs, and the results suggest differential podocyturia in dogs with CKD, according to the stage of the disease, i.e. an increase in podocyturia in dogs at stage 1 or 2 and a reduction in podocyturia in dogs at stage 3 or 4.

Dogs with chronic kidney disease (CKD) may have alterations in the glomerular filtration barrier, including podocyte loss. Detection of podocyte mRNA in urine could be useful for assessing podocyturia in dogs with kidney disease. The objective of this study was to evaluate the presence of nephrin mRNA (NPHS1) and podocin mRNA (NPHS2) in urine sediments of dogs with naturally occurring CKD and healthy dogs.

Dairy cows may infrequently give milk tinged with blood after calving, which is a condition termed haemolactia. Economic losses for dairy farmers are caused by cases of haemolactia because of the condemnation of such milk, potential contamination of good bulk tank milk with haemolactic milk, and need for veterinarian intervention. This study was performed to elucidate the oxidative status of dairy cows with haemolactia during the peripartum period. Plasma glutathione peroxidase, malondialdehyde (MDA) and superoxide dismutase concentrations along with serum vitamin A, C and E concentrations were determined as indices of oxidative stress. The sampled dairy cows comprised two haemolactic (n = 11 and n = 6) and two non-haemolactic (n = 11 and n = 6) groups. On the first day when haemolactia was identified in colostrum (at mean 2.1 days after parturition), a significantly increased concentration of plasma MDA was noted in the haemolactic group. During the prepartum period, low levels of serum vitamin E were continuously observed from prepartum week 4 to the parturition day but only in the haemolactic group. These results demonstrate that continuous low levels of serum vitamin E in the prepartum period may play a pivotal role as a requisite factor in the onset of haemolactia after calving.

Dairy cows may infrequently give milk tinged with blood after calving, which is a condition termed haemolactia. Economic losses for dairy farmers are caused by cases of haemolactia because of the condemnation of such milk, potential contamination of good bulk tank milk with haemolactic milk, and need for veterinarian intervention. This study was performed to elucidate the oxidative status of dairy cows with haemolactia during the peripartum period.

The aim of the study was to present cases of botulism in animals found in Poland in 2019–2021. The analytical laboratory diagnosis and difficulties that occurred in the interpretation of the results are described. From 2019 to 2021, samples of serum, intestinal content, liver, spleen, kidney, faeces, wet feed, dry feed, ensilage, water and mixed samples of internal organs associated with 10 suspected animal botulism cases were sent to the National Veterinary Research Institute. Samples were analysed using a mouse bioassay and culture methods in combination with ntnh and bont gene detection. Among the ten putative botulism cases, only four (40%) were confirmed in the laboratory on the basis of the detection of botulinum toxin (BoNT) or the ntnh or bont genes. The remaining six (60%) were determined as probable despite observable characteristic clinical signs. The diagnosis of botulism in animals is a very difficult task, made so by the heterogeneity of Clostridium botulinum strains and possible loss of toxinogenicity during laboratory processing or the potential degradation of toxins. Laboratory diagnosis is a complex and problematic process which should utilise different prescribed methods for specific types of sample.

The aim of the study was to present cases of botulism in animals found in Poland in 2019–2021. The analytical laboratory diagnosis and difficulties that occurred in the interpretation of the results are described.

Nontuberculous mycobacteria (NTM) are increasingly recognised as causative agents of opportunistic infections in humans for which effective treatment is challenging. There is very little information on the prevalence of NTM drug resistance in Poland. This study was aimed to evaluate the susceptibility to antibiotics of NTM, originally isolated from diseased ornamental fish. A total of 99 isolates were studied, 50 of them rapidly growing mycobacteria (RGM) (among which three-quarters were Mycobacterium chelonae, M. peregrinum, and M. fortuitum and the rest M. neoaurum, M. septicum, M. abscessus, M. mucogenicum, M. salmoniphilum, M saopaulense, and M. senegalense). The other 49 were slowly growing mycobacteria (SGM) isolates (among which only one was M. szulgai and the bulk M. marinum and M. gordonae). Minimum inhibitory concentrations for amikacin (AMK), kanamycin (KAN), tobramycin (TOB), doxycycline (DOX), ciprofloxacin (CIP), clarithromycin (CLR), sulfamethoxazole (SMX), isoniazid (INH) and rifampicin (RMP) were determined. The majority of the isolates were susceptible to KAN (95.95%: RGM 46.46% and SGM 49.49%), AMK (94.94%: RGM 45.45% and SGM 49.49%), CLR (83.83%: RGM 36.36% and SGM 47.47%), SMX (79.79%: RGM 30.30% and SMG 49.49%), CIP (65.65%: RGM 24.24% and SGM 41.41%), and DOX (55.55%: RGM 9.06% and SGM 46.46%). The majority were resistant to INH (98.98%: RGM 50.50% and SGM 48.48%) and RMP (96.96%: RGM 50.50% and SGM 46.46%). The drug sensitivity of NTM varies from species to species. KAN, AMK, CLR and SMX were the most active against RGM isolates, and these same four plus DOX and CIP were the best drugs against SGM isolates.

Nontuberculous mycobacteria (NTM) are increasingly recognised as causative agents of opportunistic infections in humans for which effective treatment is challenging. There is very little information on the prevalence of NTM drug resistance in Poland. This study was aimed to evaluate the susceptibility to antibiotics of NTM, originally isolated from diseased ornamental fish.

Trypanosomosis is an important disease of dromedary camels caused by the pathogenic protozoan Trypanosoma evansi. This study aimed to compare three different tests for its diagnosis in this species: conventional microscopy, the card agglutination test for trypanosomosis/T. evansi (CATT/T. evansi) and real-time PCR. Whole blood and serum samples collected from 77 dromedary camels of Abu Dhabi, United Arab Emirates, were analysed with the test methods stated. Statistical analysis was done using McNemar’s chi-squared test, and Cohen’s kappa index (κ) was calculated. We obtained results with positivity of 18% (14/77) by microscopy, 22% by CATT (17/77) and 60% (46/77) by real-time PCR, with the chain reaction detecting at a respectively three- and two-fold greater rate than the other techniques. Analysis of the data revealed a relative sensitivity of 30.4% and 37.0% for microscopy and CATT, respectively, compared to real-time PCR. The difference between the real-time PCR’s sensitivity and those of the other methods was statistically significant, with X² values of 30.03 and 20.1, respectively (df = 1 and P = 0.05 in both cases). Agreement of microscopy results with those of with CATT was good (κ = 0.72; 95% CI = 0.62–0.82). Cohen’s kappa index showed fair agreement of real-time PCR with microscopy (κ = 0.26; 95% CI = 0.16–0.36) whereas it was in poor agreement with CATT (κ = 0.09; 95% CI = 0.02–0.15). Real-time PCR was found to be more sensitive than microscopy and CATT.

Trypanosomosis is an important disease of dromedary camels caused by the pathogenic protozoan Trypanosoma evansi. This study aimed to compare three different tests for its diagnosis in this species: conventional microscopy, the card agglutination test for trypanosomosis/T. evansi (CATT/T. evansi) and real-time PCR.

Fasciola hepatica is a trematode infecting ruminants worldwide and occasionally affecting other animal species, including humans. It causes significant economic losses. Geographic distribution and patterns of infection must be considered before control and management measures are developed for this parasite. DNA molecular markers are useful for the identification of flukes and elucidation of their genetic evolution. Therefore, the population structure of F. hepatica was studied using this method in sheep in Xinjiang, China. The molecular characteristics, genetic relationships within the population and dispersal patterns of F. hepatica isolates were analysed based on the cox1 and nad1 genes. The population structure of F. hepatica from three regions of Xinjiang was explored and a neutrality test was conducted. The cox1 and nad1 genes have 21 and 42 variable sites, respectively, which can be classified into 34 and 33 haplotypes. Median-joining network and phylogenetic tree analyses showed that there was no significant variation in F. hepatica isolates between the three geographical regions. Analysis of variance revealed that the genetic variation of F. hepatica was mainly present within the populations. The neutrality test indicated that the populations were relatively stable but the Hami population may have undergone short-term expansion. This study revealed for the first time the molecular characteristics, genetic diversity and dispersal patterns of F. hepatica isolates from sheep in Xinjiang, thus providing new insights into the genetic variation and haplotype diversity of F. hepatica from indigenous sheep.

Fasciola hepatica is a trematode infecting ruminants worldwide and occasionally affecting other animal species, including humans. It causes significant economic losses. Geographic distribution and patterns of infection must be considered before control and management measures are developed for this parasite. DNA molecular markers are useful for the identification of flukes and elucidation of their genetic evolution. Therefore, the population structure of F. hepatica was studied using this method in sheep in Xinjiang, China.

Cadmium and zinc are often found in aquatic environment and may accumulate in living organisms. The aim of this study was to evaluate the genotoxic effect of Cd, Zn, and their binary mixture on the peripheral blood erythrocytes of Prussian carp (Carassius gibelio B.).

Introduction: Cadmium and zinc are often found in aquatic environment and may accumulate in living organisms. The aim of this study was to evaluate the genotoxic effect of Cd, Zn, and their binary mixture on the peripheral blood erythrocytes of Prussian carp (Carassius gibelio B.). Material and Methods: The fish were exposed to 4.0 mg/L Cd, 4.0 mg/L Zn or a mixture of 4.0 mg/L Cd and 4.0 mg/L Zn for a period of 14, 21 or 28 days. Genotoxic effects were investigated in peripheral blood cells using the comet assay and the erythrocyte micronucleus assay. Results: The results demonstrated that the frequencies of micronuclei (MN) and both nuclear and cellular abnormalities in erythrocytes were significantly higher in all exposure groups as compared to the control group. The fish exposed to the mixture of Cd and Zn presented the highest frequency of MN. Furthermore, there was a decrease in the frequency of MN and an increase in the occurrence of DNA integrity defects (DNA damage) with longer time of exposure to the metals studied. Conclusion: Erythrocyte micronucleus and comet assays confirmed the genotoxicity of Cd and Zn. The results of the tests applied (which showed considerable variability) suggest the involvement of various toxicity mechanisms. Therefore, an integrative and comprehensive approach, using a set of assays for toxicity profile determination, should be adopted during ecotoxicological studies and environmental risk assessment pertaining to these elements. | genotoxicity, heavy metals, erythrocyte micronucleus assay, comet assay, Prussian carp. | 140 | 619-628 | 4