Urokinase plasminogen activator expression in canine malignant mammary tumours by immunohistochemical study

Immunohistochemical expression of urokinase plasminogen activator (uPA) was studied in 37 canine malignant mammary tumours to define the relationship between their histopathological type and grade. In 29 (78.4%) cases, expression of uPA by neoplastic cells was more than 10% and in 34 samples (91.9%) uPA expression by stromal cells (fibroblasts) was more than 10%. The uPA was expressed in epithelial and myoepithelial cells of carcinomas and carcinosarcomas and mesenchymal population of carcinosarcoma, chondrosarcoma, and carcinomas arising in benign tumours. The intensity and percentage of expression of uPA by stromal cells was associated with their histological grade (P < 0.05). However, no significant relationship was detected between uPA expression by neoplastic cells (epithelial, myoepithelial, and mesenchymal cell) and histological grade. Increased expression of uPA by tumour stroma was associated with poor prognostic factors. Stromal expression of uPA could be a prognostic indicator for canine mammary tumours.

Concentrations of toxic elements in tissues of slaughtered animals and cow’s milk - a five year study

The aim of the study was to evaluate the contamination of animal muscle, liver, and milk with lead, cadmium, mercury, and arsenic. Determination of the elements was carried out using several techniques of atomic absorption spectrometry. Between 2008 and 2012, samples of muscles and liver from 1305 cattle, 2345 pigs, 758 horses (only muscles), 1721 poultry (chickens, turkeys, geese, ducks), and 736 samples of raw milk were collected. Only 48 (0.7%) samples exceeded the maximum acceptable levels of the elements, especially lead and cadmium. In the case of lead, the highest number of samples exceeding the legal limits was found in muscles of pigs (6), where the maximum value reached 0.376 mg/kg. For cadmium, the highest number of samples (22) with values exceeding legal limits was found in muscles of horses. The cadmium content in muscles of horses, at both the mean (0.052 mg/kg) and median (0.023 mg/kg), was in order of magnitude higher than that observed in cattle and pigs. Small percentage of samples with values exceeding the maximum levels of toxic elements in food of animal origin indicates a low risk for the consumers’ health.

Influence of dietary soy isoflavones on immature hamster uterotrophic and Hershberger assays

To select appropriate diet for hamsters used in the uterotrophic and Hershberger assays two rodent diets were compared: Murigran (Agropol, Poland) and Altromin 7010 (Altromin Spezialfutter GmbH&Co., Germany). The contents of bioactive compounds in feeds were evaluated by liquid chromatography, and their oestrogenic activity by yeast enhanced green fluorescent protein assay. In opposition to Altromin, Murigran contained high amounts (μg/kg) of genistein (765 600) and daidzein (132 000), and the oestrogenic activity of these compounds, expressed as 17β-oestradiol equivalent concentration (EEQ), was found to be 9.54 μg EEQ/kg. In in vivo study, Murigran induced a high degree of oestrogenisation in immature hamsters, and females failed to exhibit a normal uterine response to recommended dose of a model oestrogen agonist 17α-ethinyloestradiol. There was no influence of the diet on the weight of five accessory sex organs (ASO): ventral prostate, seminal vesicles with coagulating glands, levator ani bulbocavernosus muscles, Cowper`s glands, and glans penis of control males. However, the impact on ASO response to model androgen agonist, testosterone propionate was observed. The obtained results provide the evidence that phytooestrogen-rich feed modulates the oestrogenic and androgenic response to chemicals.

Microbiological quality of feed materials used between 2009 and 2012 in Poland

The study was conducted at all regional veterinary diagnostic laboratories. Feed materials were examined for Salmonella prevalence and contamination by Enterobacteriaceae, aerobic mesophilic bacteria, total plate count, fungi, Clostridium sp., and Bacillus cereus. Assays were done following international and Polish standards used in food and feed microbiology. Salmonella sp. were most often detected in oil seeds. In most of the examined feed ingredients, the number of Enterobacteriaceae did not exceed 10 cfu/g. The contamination by aerobic bacteria ranged most often from 101to 107 cfu/g, and the highest mycological contamination was noted in cereal grains (108 cfu/g). The results showed that microbial contamination of feed materials in regard to Enterobacteriaceae, fungi, and total plate counts declined over the past years.

DNA based approaches for the detection and identification of bovine meat and bone meal in feeds

The aim of this paper was to present the results of comparative evaluation of the usefulness of PCR method for the detection and identification of bovine DNA in feeds. In the validation study, the limit of detection for PCR was determined as 0.05% for bovine meat and bone meal (MBM). Among 132 feed samples, bovine DNA was detected in eight (6.06%) samples. In the next stage of the study, sediment and flotate from the investigated samples were examined with PCR. Out of 132 sediment and flotate samples, bovine DNA was detected in eight (6.06%) and nine (6.82%) samples, respectively. On the basis of the results obtained with the use of the PCR, it is possible to state that the molecular biology methods can, at present, be used as supplementary tools for detection and identification of bovine MBM.

Immunomodulatory effect of Mycoplasma bovis in experimentally infected calves

The effect of three different field isolates of Mycoplasma bovis on selected immunological parameters in experimentally infected calves was studied. Calves were kept separately in 4 experimental groups, and animals of 3 groups were infected intratracheally with one of the three selected isolates of M. bovis. The control group was inoculated intra-tracheally with sterile physiological saline. Nasal swabs and blood samples were collected just before the calf inoculation, then daily for seven days, and then weekly for another three weeks. The presence of M. bovis antigen, M. bovis antibodies, total protein, gamma globulins, IgA, IgM, IgG, acute phase proteins (haptoglobulin and serum amyloid A), as well as interferon-γ and interleukin-4 concentrations were determined. M. bovis was detected intermittently during the study in the infected groups from day 1, whilst the control group remained free of the pathogen. M. bovis antibodies were detected in some of infected animals in the second, third, and fourth week after infection. The stimulation and/or immunological suppression varied between the M. bovis isolates used for the inoculation. All M. bovis isolates induced a rise of APP and gamma globulin concentrations in infected calves. However, in this study the mucosal immune response appeared to be down-regulated, which was expressed with a general lack of IgA stimulation.

Prevalence and molecular characteristics of rotaviruses from Polish turkey flocks between 2008 and 2011

Between 2008 and 2011, commercial turkey flocks in Poland were examined for the presence of rotaviruses. Ten faecal swabs from each of 207 turkey flocks (turkeys aged one to 19 weeks) were collected in different regions of the country and tested using a PCR assay that targeted the NSP4 gene. The prevalence of rotavirus was 20.3% in the flocks tested. Phylogenetic analysis revealed a clear division into groups dependent on geographical origin of the analysed viruses. All Polish rotaviruses belonged to the European group. However, they were found to be genetically variable based on the sequence analysis. The most frequently identified rotaviruses belonged to RV-1 subgroup and two of them formed a distinct subgroup of RV-2. Rotaviruses were detected in healthy and enteric turkeys. The observed amino acid changes probably did not affect the group affiliation, nor the pathogenecity of the studied rotavirus strains.

Influence of fluoroquinolones on viability of Balb/c 3T3 and HepG2 cells

The cytotoxic potential of fluoroquinolones (enrofloxacin, ciprofloxacin, difloxacin, sarafloxacin, danofloxacin, norfloxacin and marbofloxacin) was investigated using mouse fibroblasts Balb/c 3T3 and human hepatoma HepG2 cell lines. The cells were exposed for 24, 48, and 72 h to drugs at eight concentrations ranged from 0.78 to 100 μg/mL. Four independent cytotoxicity assays were applied, in which various endpoints were assessed: mitochondrial activity - MTT reduction, lysosomal activity - neutral red uptake, total protein content, and cellular membrane integrity - lactate dehydrogenase release. Mean effective cytotoxic concentrations (EC50) calculated at different time points from concentration-response curves ranged from 10 to 100 μg/mL. The most affected endpoint in both cell lines was mitochondrial activity. The EC50-MTT-72 h <10 μg/mL was found for difloxacin, marbofloxacin (fibroblasts), sarafloxacin, and norfloxacin (HepG2). The data shows that cytotoxicity of the fluoroquinolones appears after longer exposure of both cell cultures to these compounds.

Official control of ochratoxin A in food of animal origin in Poland between 2003 and 2012

Between 2003 and 2012, 1413 samples of kidneys, liver, and muscles from swine, cattle, sheep, horses, chickens, turkeys, geese, ducks, and fish were examined for the presence of ochratoxin A. The examination was performed in the framework of “The National Residue Control Programme for Chemical, Biological, and Drug Residue in Animal Tissues and in the Food of Animal Origin”. The mycotoxin was determined by liquid chromatography with fluorescence detection after immunoaffinity column clean up. The limit of quantification was 0.2 μg/kg. Ochratoxin A was found only in swine kidney samples (n = 1092). It was detected in 28.8% of the kidney samples at the concentrations from 0.2 to 29.2 μg/kg. The most of the samples (25.5%) contained OTA at the concentration ranging from 0.2 to 5 μg/kg, which is below the provisional action level for OTA in kidneys, established in Poland at the concentration of 5 μg/kg. Furthermore, 24 (2.2 ) samples had mycotoxin concentrations between 5 and 10 μg/kg and 13 (1.2 ) samples above 10 μg/kg.

ERIC-based differentiation and antimicrobial susceptibility of Yersinia enterocolitica O:9 isolated from animals serologically positive and negative for brucellosis

The paper presents the results of genotypic differentiation and antimicrobial susceptibility of Y. enterocolitica O:9 isolates that originated from cows and pigs positive in serological reactions for brucellosis, and also from the animals, which were serologically negative. The genetic relationship between Y. enterocolitica O:9 isolates originating from different sources was determined by the use of ERIC-PCR, and resulted in detection of 6 to 13 DNA amplicons of different size. The clonal analysis was based on dendrogram created by Unweighted Pair Group Method with arithmetic mean and Jaccard’s coefficient, which enabled to divide Y. enterocolitica O:9 isolates into 16 different clonal groups. Among all Y. enterocolitica O:9, MIC value was >32 mg/L for the ampicillin, ≤0.008 mg/L for ciprofloxacin, ≤8 mg/L for sulphametoxazole, ≤2 mg/L for colistin, and ≤1 mg/L for tetracycline. The wide range of MIC for ceftazidime (≤0.25-2 mg/L) and cefotaxime (≤0.06-1 mg/L) among Y. enterocolitica O:9 isolates was also observed. No significant differences were observed between MIC values of Y. enterocolitica O:9 isolates originating from animals serologically positive for brucellosis, and the isolates from cows and pigs, which provided serologically negative reactions.