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The aim of the study was to determine the level of antioxidant vitamins A and E in the liver of rats exposed to chlorpyrifos and/or enrofloxacin. Chlorpyrifos (Group I) was administered at a dose of 0.04 LD50 (6 mg/kg b.w.) for 28 days, and enrofloxacin (Group II) at a dose of 5 mg/kg b.w. for 5 consecutive days. The animals of group III were given both of the mentioned above compounds at the same manner as groups I and II, but enrofloxacin was applied to rats for the last 5 days of chlorpyrifos exposure (i.e. on day 24, 25, 26, 27 and 28). Chlorpyrifos and enrofloxacin were administered to rats intragastrically via a gastric tube. The quantitative determination of vitamins was made by the HPLC method. The results of this study indicated a reduction in the hepatic concentrations of vitamins A and E, compared to the control, which sustained for the entire period of the experiment. The four-week administration of chlorpyrifos to rats resulted in a significant decrease of vitamins in the initial period of the experiment, i.e. up to 24 hours after exposure. For vitamin A the maximum drop was observed after 24 hours (19.24%) and for vitamin E after 6 hours (23.19%). Enrofloxacin caused a slight (3-9%) reduction in the level of the analysed vitamins. In the chlorpyrifos-enrofloxacin co-exposure group reduced vitamins A and E levels were also noted, but changes in this group were less pronounced in comparison to the animals intoxicated with chlorpyrifos only. The decrease in the antioxidant vitamin levels, particularly noticeable in the chlorpyrifos- and the chlorpyrifos combined with enrofloxacin-treated groups, may result not only from the increase in the concentration of free radicals, but also from the intensification of the secondary stages of lipid peroxidation.

This study examined the effect of chlorpyrifos and/or enrofloxacin on the activity of acetylcholinesterase (AChE) in the blood and brain, and the activity of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum. The experiment was conducted on Wistar strain rats. Chlorpyrifos was administered with a stomach tube at a dose of 0.04 LD50 for 28 days and enrofloxacin at a dose of 5 mg/kg bw for 5 consecutive days. The experiment found that enrofloxacin changed the activity of the enzymes under study only to a small extent. At the dose applied in the experiment, chlorpyrifos decreased the activity of AChE significantly, both in blood and in the brain, and increased the activity of ALT and AST in rat serum. The administration of chlorpyrifos in combination with enrofloxacin changed the activity of the enzymes under study only slightly. A weaker, but longer, inhibition of AChE activity in both blood and the brain was observed in this group compared to the animals exposed only to chlorpyrifos. However, although enrofloxacin, like chlorpyrifos, increases the activity of ALT and AST in serum, their combined administration did not increase the hepatotoxic effect.

The study was undertaken to examine the effect of single and combined administration of dimethoate (an OP insecticide) and pyrantel embonate (an anthelmintic agent) on the concentration of reduced glutathione (GSH) and the activity of glutathione peroxidase (GPx) and glutathione reductase (GR) in rats. Dimethoate (Group I) was administered to rats at a dose of 1/10 LD50for 5 consecutive days and pyrantel embonate (Group II) at a dose of 1/5 LD50for 3 consecutive days. The animals of group III were given both of the mentioned above compounds in the same manner as group I and II, but pyrantel embonate was applied on day 3, 4, and 5 from the beginning of dimethoate intoxication. Material from 6 rats randomly selected from each group was obtained after 3, 6 and 12 hours and 2, 7 and 14 days following the last applied dose of the compounds under study. It was found that application of pyrantel embonate caused only slight changes in the analysed parameters i.e. GSH, GPx and GR. Dimethoate administration caused disturbances in the antioxidative system manifested as a decrease in GSH concentration in the liver (max. - 37.7% after 6 hours) and an increase of GPx and GR activities in erythrocytes (max. - 21.7% and 29.6% after 3 hours, respectively), compared to the control group. The profile of changes after combined intoxication was similar, but their intensity was higher compared to the group of animals exposed to dimethoate only. Based on current studies, it was concluded that both dimethoate and pyrantel embonate at the applied doses showed a pro-oxidative activity.

In the present study influence of doxazosin on the porcine urinary bladder contractility has been examined. Immature pigs were treated for 30 days with: a) doxazosin (n = 5) per os at a dose of 0.1 mg/kg b.w. or b) placebo (n = 5; control group). Thereafter, animals were sacrificed and urinary bladder strips from the trigone were suspended in organ baths. The tension of the smooth musce was measured before and after exposition to acetylocholine (ACh; 10-5 - 10-3 M), norepinephrine (NE; 10-9 - 10-7 M) and 5-hydroxytryptamine (5-HT; 10-7 - 10-5 M). Both the ACh and 5-HT at the highest doses significantly increased the contractility in each group, but this response was weaker in doxazosin-treated animals. NE caused relaxation in both groups, but the effect was weaker in doxazosine-treated group. The results of our study have shown that long-term administration of doxazosin caused a desensitization of the detrusor smooth muscle for in vitro applied mediators of the autonomic nervous systems.

WC1+ cells in cattle exhibit both regulatory and effector activities. However, it has not been elucidated whether they are so plastic that both activities co-exist in one cell or there are separate subpopulations of effector and regulatory cells. Since the production of IFN-gamma and IL-10 seems to be related to WC1+ cells' effector and regulatory function, respectively, the main aim of this study was to determine whether those cytokines are produced by separate subpopulations of WC1+, or are co-produced by the same cells. Due to increasingly frequent emphasised role of consumption of IL-2 in the mechanism of suppressor action of mouse CD25+CD4+ T regulatory cells, expression of the receptor's alpha chain for interleukin 2 (CD25) on WC1+ lymphocytes has been evaluated. An average of 5.21% of WC1+ cells obtained from PBMCs of 12-month-old heifers show constitutive expression of the CD25 molecule, with CD25(high)WC1+ and CD25(low)WC1+ cells accounting for 1.05% and 4.10% of WC1+ lymphocytes, respectively. For detection of intracellular cytokine production, PBMCs were stimulated with concanavalin A. Both IFN-gamma(-) and IL-10-producing cells within the CD25(-)WC1+ and CD25+WC1+ subpopulations were mainly separate subpopulations. The average percentage of IFN-gamma(+)IL-10(-), IFN-gamma(-)IL-10+ and IFN-gamma(+)IL-10+ cells among CD25(-)WC1+ lymphocytes was 4.03%, 2.67% and 0.51%, respectively. A positive correlation was observed between the presence of the CD25 molecule on WC1+ lymphocytes and production of IL-10 and TGF-beta, because the average percentage of IFN-gamma(-)IL-10+ and IFN-gamma(+)IL-10+ among CD25+WC1+ lymphocytes was 3 and 4.5 times higher as compared to the corresponding cells in the CD25(-)WC1+ subpopulation, whereas the percentage of IFN-gamma(+)IL-10(-) cells in both the subpopulations was not significantly different. The percentage of TGF-beta+ cells within the CD25+WC1+ subpopulation was 2.72 times as high as that of CD25(-)WC1+ lymphocytes. Therefore, with respect to the production of IFN-gamma, IL-10 and TGF-beta, CD25+WC1+ lymphocytes turn out to have a more suppressor profile than CD25(-)WC1+.

WC1+ cells in cattle exhibit both regulatory and effector activities. However, it has not been elucidated whether they are so plastic that both activities co-exist in one cell or there are separate subpopulations of effector and regulatory cells. Since the production of IFN-gamma and IL-10 seems to be related to WC1+ cells' effector and regulatory function, respectively, the main aim of this study was to determine whether those cytokines are produced by separate subpopulations of WC1+, or are co-produced by the same cells. Due to increasingly frequent emphasised role of consumption of IL-2 in the mechanism of suppressor action of mouse CD25+CD4+ T regulatory cells, expression of the receptor's alpha chain for interleukin 2 (CD25) on WC1+ lymphocytes has been evaluated. An average of 5.21% of WC1+ cells obtained from PBMCs of 12-month-old heifers show constitutive expression of the CD25 molecule, with CD25(high)WC1+ and CD25(low)WC1+ cells accounting for 1.05% and 4.10% of WC1+ lymphocytes, respectively. For detection of intracellular cytokine production, PBMCs were stimulated with concanavalin A. Both IFN-gamma(-) and IL-10-producing cells within the CD25(-)WC1+ and CD25+WC1+ subpopulations were mainly separate subpopulations. The average percentage of IFN-gamma(+)IL-10(-), IFN-gamma(-)IL-10+ and IFN-gamma(+)IL-10+ cells among CD25(-)WC1+ lymphocytes was 4.03%, 2.67% and 0.51%, respectively. A positive correlation was observed between the presence of the CD25 molecule on WC1+ lymphocytes and production of IL-10 and TGF-beta, because the average percentage of IFN-gamma(-)IL-10+ and IFN-gamma(+)IL-10+ among CD25+WC1+ lymphocytes was 3 and 4.5 times higher as compared to the corresponding cells in the CD25(-)WC1+ subpopulation, whereas the percentage of IFN-gamma(+)IL-10(-) cells in both the subpopulations was not significantly different. The percentage of TGF-beta+ cells within the CD25+WC1+ subpopulation was 2.72 times as high as that of CD25(-)WC1+ lymphocytes. Therefore, with respect to the production of IFN-gamma, IL-10 and TGF-beta, CD25+WC1+ lymphocytes turn out to have a more suppressor profile than CD25(-)WC1+.

This study presents the results of research concerning the effect of single and combined application of pyrantel tartrate and dimethoate on selected antioxidative enzymes: catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx), in rat erythrocytes. Pyrantel tartrate was applied twice, at a dose of 85 mg/kg bw at a two week interval, i.e. on day 14 and 28 of the experiment, orally, in a water solution with a stomach tube. Dimethoate was administered with drinking water for 28 days at a dose of 25 mg/kg bw/day. It was found that pyrantel tartrate caused only small changes in the activity of the antioxidative enzymes under analysis. Subchronic exposure of rats to dimethoate caused a significant increase in the activity of CAT, SOD and GPx in erythrocytes, indicating the existence of strong oxidative stress. In combined intoxication, no significant effects of administering pyrantel tartrate on the activity of CAT, SOD and GPx was found in animals poisoned with dimethoate. The profile of changes was similar to that observed in rats exposed only to the organophosphorus insecticide. This may indicate a lack of interaction between the compounds used in the experiment.

The aim of the study was to investigate the influence of administration of chlorpyrifos and/or enrofloxacin on the activity of chosen antioxidative enzymes i.e.: superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) in erythrocytes of rats. Chlorpyrifos was administered by stomach tube during 28 days at a dose of 3 mg/kg bw (0.02 LD50), and enrofloxacin was administered by stomach tube at a dose of 5 mg/kg bw during 3 subsequent days. It was stated that administration of enrofloxacin at applied dose did not cause any major changes in the activity of investigated antioxidative enzymes. The four-week exposure of rats to chlorpyrifos caused noticeable decrease in SOD and CAT activity in erythrocytes of rats at the beginning of the experiment (up to 24th hour) in comparison with the control group. The activity of GPx during all periods of the experiment was increased. In the group of animals in which both chlorpyrifos and enrofloxacin were applied, the profile of changes in activity of examined enzymes was similar to that one, which was observed after administration of chlorpyrifos exclusively, what may indicate lack of co-action between compounds used in the experiment.

"Effective Microorganisms" (EM)--a mixture of lactic acid bacteria, photosynthetic bacteria, yeasts and fungi are used mainly in agriculture and organic waste treatment. Recently, they have also been added to water and feed for animals, as well as to processing their excrements into compost and to eliminate the stench. The objective of the present study was to assess the influence of a 14-day administration of an EM solution in drinking water to layer hens on chosen haematological and biochemical indexes. The research was carried out on 120 hens divided into two equal groups. The birds in the experimental group were given drinking water with dissolved EM (5% solution), and those in the control group--water without the preparation. On the 64th day of the aviculture, the hens were weighted and their blood was taken from the wing vein for haematological and biochemical examinations. Administering EM with water to hens did not influence significantly their body weight nor chosen haematological and biochemical indexes. A significant increase was found only in the number of platelets, the level of albumins, the content of total cholesterol and the LDH activity, however, a decrease in the ALT activity was observed.

The behaviour of Dermanyssus gallinae was investigated on two layer farms where two different light programs were introduced in the 40th week of hen life. In layer house No. 1, light was applied continuously for 16 hours during the day, while layer house No. 2 was subjected to 4 hours of light and 2 hours of darkness applied alternately during the day. To monitor the level of red mite infestation, 30 tube traps were placed in every layer house corridor at a height of 1.5 m above the floor. In the first layer house, 280 Dermanyssus gallinae females, 50 nymph larvae and 198 eggs were found in 100 mg of tube trap material during 16 hours of the light phase, while during the 8-hour darkness phase, 1240 females, 70 nymph larvae and 110 eggs were collected. In the other layer house (with an alternating light phase of 4 hours and a darkness phase of 2 hours per day), 387 Dermanyssus gallinae females, 401 nymph larvae and 1060 eggs were found in trap tubes over the 8-hour dark phase, while 343 females, 202 nymph larvae and 1106 eggs were discovered over the 16-hour light phase.

The study was aimed at determining the dimethoate residues in the liver and acetylcholinesterase (AChE) activity in blood of rats exposed to dimethoate (individual intoxication), and dimethoate and pyrantel embonate (simultaneous intoxication). The experiment was carried out in two stages where various doses of preparations and exposure manners were used. In the first stage of the experiment, dimethoate (1/25 LD50) was administered to animals per os for 28 days, and pyrantel embonate (1/2 LD550) twice, i.e. on the day 14th and 28th. In the second stage, dimethoate was administered for 5 days (1/10 LD50), and pyrantel embonate (1/5 LD50) on day 3, 4 and 5 from the beginning of dimethoate intoxication. The short presence of the dimethoate residues in the liver of the animals examined was found until the 2nd day after 28-day intoxication (1/25 LD50) and until 14th day after 5-day intoxication (1/10 LD50), however, a distinct decrease in this insecticide residues in the liver of (analysed groups of) rats occurred between the 3rd hour and the 2nd day after exposure. Dimethoate in both applied doses significantly reduced AChE activity in blood. After application of the higher dose, the inhibition of AChE was more pronounced, and the return of its activity to physiological values lasted considerably longer. Co-administration of pyrantel embonate and dimethoate, slightly influenced changes of the parameters analysed, which have been dependent not only on a dose and manner of pyrantel application but also on time which lapsed from exposure.