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Cortisol levels were measured in hair, blood and milk in two different cattle breeds, kept under different breeding conditions and with different genetic merit for milk production. Cows and heifers of Holstein and Busha breeds were selected for the study. Cortisol concentration was determined by immunoassays. Cortisol accumulation was determined in proximal (close to the skin) and distal (far from the skin) segments of the hair shaft. The influence of hair colour and washing prior to extraction and analysis was also examined in order to establish additional factors that may have an impact on hair cortisol concentrations. Concentrations of cortisol determined in the proximal and distal segments of the shaft were significantly higher in Holstein than Busha cows and heifers (P<0.05 and P<0.01, respectively). In Holstein cows, no significant difference was found between concentrations in black and white hair. In hair washed with isopropanol, cortisol concentration was significantly lower compared to unwashed hair (P<0.01). Thus, cortisol concentration in hair varies with the technique of hair processing (washing), but not with colour in Holstein cows. Blood serum cortisol concentrations in Holstein cows and heifers were significantly higher than in Busha cows and heifers, (P<0.01 and P<0.05, respectively). Milk cortisol in Holstein cows was significantly higher than in Busha cows (P<0.05). The higher cortisol concentrations in Holstein cows are assumed to be the result of intensive breeding and physiological adaptation to high milk production.

Residues of acaricide coumaphos were assessed in honey, bee brood, and beeswax during a 2-year field experiment. Honey, bee brood, and beeswax samples were collected before and after routine use of coumaphos in the treatment of bee colonies against varroosis in two consecutive years. Determination of coumaphos in honey and bee brood was based on RP-HPLC with UV detection after a liquid-liquid extraction with hexane or ethyl acetate. Coumaphos in beeswax was identified and quantified by GC/MS. Results indicate the undetectable presence of coumaphos in honey. In bee brood, coumaphos was observed after the treatment. In beeswax, the accumulation of coumaphos was determined not only in hives where it was used but also in hives nearby in which coumaphos was not used. Results indicate the accumulation of coumaphos in bee brood and beeswax. Due to the coumaphos accumulation this drug should be used only in strongly affected bee colonies.

The aim of the present study was to investigate the effect of meloxicam and meloxicam with misoprostol on prostaglandin E2 (PGE2) and prostaglandin I2 (PGI2) serum concentration, as well as on gastrointestinal permeability. NSAIDs, such as meloxicam, have gastrointestinal side effects, which are due to prostaglandins depletion and topical damage. Seven adult beagle dogs were included in the study. Three different 20 days long treatments were carried out (placebo, meloxicam and meloxicam with misoprostol). The same seven dogs participated in all three treatments. On days 1 to 10 the dogs received placebo, meloxicam or meloxicam together with misoprostol PO. Dogs were than monitored from day 11 to 20. Samples for serum PGE2 and PGI2 concentration and plasma lactulose, mannitol and sucrose concentration determination were drawn on day 0, 2, 6, 11 and 20. Lactulose/mannitol (L/M) index was calculated. Treatment with meloxicam and meloxicam with misoprostol resulted in lower PGE2 and PGI2 serum concentrations in comparison to the placebo. L/M index and sucrose plasma concentration were increased in both groups in comparison to the placebo. According to the results of the study, meloxicam has altered gastrointestinal permeability and depleted prostaglandins production. Misoprostol was shown to be an effective preventing treatment

The influence of sublethal doses of 2,4-dichlorophenoxyacetic acid (2,4-D) on serum T3 and T4 concentrations in Hsd Cpb: Wistar rats of both sexes was studied. The trial was performed on 24 males and females respectively, each divided into three groups of 8 animals (control, groups 1 and 2). Aqueous solution of the compound (11 mg/kg body weight--group 1 and 110 mg/kg body weight--group 2) or clean tap water (control group) was used. Aliquots of 2.4 ml/kg body weight were administered with a stomach tube from the 1st to 10th day of the experiment. Three days before the first treatment and on the 6th and 13th day of the experiment the serum T3 and T4 concentrations were determined by commercial radioimmunoassay kits (Byk-Sangtec Diagnostica), validated for rats. A significant decrease of serum T4 (P < 0.01) and T3 (P < 0.001) was determined in males of groups 1 and 2 during the experiment. On the 6th day of experiment serum T4 and T3 values were significantly lower (P < 0.001 and 0.01 respectively) in group 2 than in the controls and group 1 of both males and females. During the whole experiment serum T4 levels were lower in females than in males (P < 0.05).

Introduction. The aim of this study was to determine estrone (E1), 17β-estradiol (E2) and progesterone (P4) concentrations in processed milk with different fat contents and to compare the concentrations of these hormones in commercial ultrahigh temperature (UHT) processed milk and commercial pasteurized milk. Materials and Methods. Commercial milks with different fat contents (UHT 0.5 %, UHT 1.5 %, UHT 3.5 % and pasteurized 3.5 % (10 samples of each type of milk)) were purchased in local stores. E1, E2 and P4 concentrations were determined by commercial ELISA kits. Results and Conclusions. E1 concentrations were below the limit of detection (15 pg mL-1) in all milks except in two UHT 3.5 % (out of 10) and two pasteurized 3.5 % (out of 10) milk samples. Mean E2 and P4 concentrations in UHT 3.5 % milk (25.37 ± 1.15 pg mL-1 and 10.76 ± 0.43 ng mL-1 , respectively) were significantly higher than in UHT 0.5 % milk (19.38 ± 0.79 pg mL-1 and 7.06 ± 0.26 ng mL-1 , respectively). Significant positive correlations were determined between hormone concentrations and milk fat contents. Relatively high E2 and P4 concentrations indicate that the bulk of milk in the commercial milks examined originated from pregnant cows.

The aim of the present study was to determine changes in plasma malondialdehyde (MDA) concentration and haematological and biochemical profiles in 10 clinically healthy standardbred horses subjected to a selected field exercise test. Correlations between plasma MDA, the main lipid peroxidation end-product, and muscle enzymes: creatine kinase (CK) and aspartate aminotransferase (AST) were determined in serum samples. Venous blood samples for determination of selected blood parameters were collected, immediately post exercise, and 24 and 48 hours post exercise.Significant changes in most of the biochemical and haematological parameters determined immediately after exercise reflect the normal physiological response of horses to a selected field exercise test. Most of these parameters returned to or close to the stall values within 48 hours. The concentration of plasma MDA increased immediately post exercise, though not significantly; however it increased significantly 24 hours post exercise and reached its highest value 48 hours post exercise. Thus exercise-induced oxidative stress is evidenced by increased lipid peroxidation. From the rapid decline of serum CK activity post exercise and the absence of significant correlations between MDA and serum muscle enzymes, we concluded that the selected field exercise test caused no permanent alteration in muscle cell integrity or muscle damage.