Immunohistochemical studies have become an indispensable element of establishing the correct histopathological diagnosis of poorly differentiated lesions, proving particularly suitable, and occasionally indispensable, for diagnosis of poorly differentiated neoplastic tumours. Knowledge of the mechanism of action and normal reaction of individual proteins is required in selection of the antibody pattern for a given tissue and in evaluation of the obtained results. This paper aims to promote the application of immunohistochemical techniques in routine diagnosis, especially in cases of poorly differentiated or undifferentiated tumours.

Introduction: Thyroid hormones affect protein turnover, and in the case of hypothyroidism a decrease in protein synthesis and reduced release of certain amino acids from skeletal muscles are observed. Changes in the amino acid system of skeletal muscles may be responsible for the occurrence of muscle disorders. Material and Methods: The study measured the content of selected amino acids in the gastrocnemius muscle of Wistar rats during experimental hypothyroidism induced by oral administration of methimazole at a concentration of 0.05% in drinking water for 90 d. The rats were divided into four groups: E1 (n = 6) - experimental males, E2 (n = 6) - experimental females, C1 (n = 6) - control males, and C2 (n = 6) control females. Results: A statistically significant reduction occurred in leucine, isoleucine, and 1-methylhistidine levels in males, and 1-methylhistidine in females, in comparison to the control groups. Conclusion: The hypothyroidism-induced changes in amino acid content may be responsible for the occurrence of skeletal muscle function disorders.

The aim of this article was to evaluate the influence and effects of chosen bioaccumulative substances i.e. heavy metals, pesticides, and polychlorinated biphenyls (PCBs) on fish, as well as provide information on time trends and potential threat to human health. Chemical substances which pollute water may affect living organisms in two ways. First of all, large amounts of chemical substances may cause sudden death of a significant part of the population of farmed fish, without symptoms (i.e. during breakdown of factories or industrial sewage leaks). However, more frequently, chemical substances accumulate in tissues of living organisms affecting them chronically. Heavy metals, pesticides, and polychlorinated biphenyls are persistent substances with a long-lasting biodegradation process. In a water environment they usually accumulate in sediments, which makes them resistant to biodegradation processes induced by, e.g., the UV light. These substances enter the fish through direct consumption of contaminated water or by contact with skin and gills. Symptoms of intoxication with heavy metals, pesticides, and PCBs may vary and depend on the concentration and bioavailability of these substances, physicochemical parameters of water, and the fish itself.

Introduction: The aim of the study was to evaluate the effect of administration of therapeutic doses of ceftiofur and tulathromycin on the circulating lymphocyte subpopulations in healthy pigs. Material and Methods: The study was conducted on thirty healthy 7- to 10-week-old pigs, assigned to three groups: the TUL group, injected with tulathromycin (n = 10); the CEF group, injected with ceftiofur (n = 10); and the C group, the control with no antibiotic administration (n = 10). Blood samples were collected before, during, and after treatment with antimicrobials. Lymphocyte subpopulations circulating in the blood were determined by immunostaining and flow cytometry analyses. Results: Following administration of a therapeutic dose of tulathromycin, there were no changes in the lymphocyte subpopulations circulating in blood. In contrast, administration of ceftiofur at the recommended dose decreased the absolute number of CD3+, CD21+, CD4+CD8-, CD4-CD8+, and double positive CD4CD8 cells. Conclusion: Results from the study indicate that ceftiofur possesses the ability to modulate the immune system in healthy pigs by decreasing lymphocyte subpopulations circulating in blood.

Introduction: Growing consumption of shellfish is associated with an increased risk of food poisoning. The study was carried out on live bivalve molluscs available on the Polish market between 2009 and 2013. Material and Methods: ELISA was used for the determination of the following marine biotoxins: paralytic shellfish poison (PSP), amnaesic shellfish poison (ASP), and diarrhoeic shellfish poison (DSP). The molluscs, of which seven species were examined, were obtained from wholesale companies and markets. Results: Marine biotoxins were detected below the permitted levels in 67.6% of the samples. The maximum amounts of PSP and ASP biotoxins were found in great scallops (532.6 μg/kg and 1.0 mg/kg respectively) and the peak for DSP was in blue mussels (107 μg/kg). Conclusion: The analysis of toxicological status of raw bivalve molluscs available on the market in Poland indicates that they are safe for consumers.

Introduction: Peroxiredoxin 6 (Prdx6) is a bifunctional protein and a unique 1-Cys Prdx of the peroxiredoxin family. The expression and regulation of Prdx6 are implicated in numerous physiological and pathological processes.

Introduction: The aim of the study was to explore the effect of enrofloxacin on production of selected cytokines by porcine peripheral blood mononuclear cells (PBMCs).

Increased incidence of protothecal mastitis has been recorded in several countries in the past ten years. The main goal of this article is to draw the attention of scientific and professional community to the emerging issue of mammary protothecosis. The article collates currently known facts about infection reservoirs, predisposing factors for the development of mastitis, clinical manifestations of the disease, and potential transmission routes within the herd as well as the measures for control and eradication. We would like to point out that identification of protothecal mastitis on a dairy farm is associated with a range of problems. Early detection of infected animals can be difficult because of predominantly subclinical course of early-stage infection, which easily spreads between cows via the milking system. Spontaneous recovery has not been recorded and infected cows typically develop chronic mastitis with granulomatous infiltration and progressive loss of functional parenchyma of the mammary gland. Substantial economic losses and health damages associated with mammary protothecosis strongly emphasise the need for developing effective prevention strategies aimed at control of the infection.

Introduction: The current study was designed to detect Mycoplasma agalactiae (Ma), Mycoplasma mycoides subsp. capri (Mmc), Mycoplasma capricolum subsp. capricolum (Mcc) and Mycoplasma putrefaciens (Mp) in sheep and goats with clinical signs consistent with contagious agalactia.Material and Methods: A total of 299 samples were collected from 55 mixed herds in Azarbaijan-e-Sharghi province, Iran. Samples were examined using PCR and culture methods.Results: The findings showed that in 40 herds at least one sample was positive by PCR or culture method. Moreover, out of 274 sheep samples, 101 were proved to be positive using the PCR technique and 76 were found positive using the culture method. Out of 25 goat samples, 10 were found positive using PCR and 9 were positive through the culture method. Less than 20% of isolated mycoplasmas were Ma. Ma was detected from almost all studied regions in the province while Mmc, Mcc, and Mp were detected only in a very limited area that was deemed by the research group the mixed infection zone.Conclusion: In vaccination or eradication projects, it would be more economical to focus on mixed infection zones. Further investigation on mixed infection zones could facilitate better understanding of contagious agalactia epidemiology.

Introduction: The aim of the experiment was to establish the enterotoxigenic Escherichia coli K88 (ETEC K88)-induced BALB/c mouse duodenum inflammation model. Material and Methods: Mice were administered different concentrations of E. coli K88 (1.0 × 10⁷-10⁹ CFU/mL) for 3 d by means of an esophageal catheter. Results: The results showed that the treated group expressed several significant clinical symptoms, such as reduced dietary demands and weight loss, an increased presence of IL-1α, TNF-α, and MPO in the peripheral blood, and some pathological changes in the duodenum. On the 6ᵗʰ-8ᵗʰ days, the body weight of the mice was the lowest. On the 8ᵗʰ day, there were significant differences in IL-1α, TNF-α, and MPO levels compared to the control group (P < 0.05), the gap between the duodenum mucous layer and the muscular layer had widened, the number of goblet cells was increased, and the inflammatory infiltrate and inflammation changes in the lamina propria and the mucous layer were the most obvious. Conclusion: The duodenum inflammation was the most severe on day 8; thus, the model was successfully established. In addition, varying concentrations of ETEC K88 did not significantly influence the duodenum inflammation (P > 0.05).