This research aimed to investigate the time-course effect of epichlorohydrin (ECH) on epididymal histopathology in Sprague-Dawley rats. Twenty-four male rats were randomly assigned to four groups with 6 rats in each group and were administered a single oral dose of ECH (70 mg/kg) or its vehicle. Six animals each were sacrificed on days 0 (control), 1, 2, and 7 after treatment. During the study period, clinical signs, body weights, reproductive organ weights, testicular spermatid count, epididymal sperm count, motility and morphology, and histopathology were examined. No treatment-related effects on body weights and reproductive organ weights were noted at any time point. On the contrary, sperm motility decreased slightly on days 1 and 2 after treatment and then decreased significantly on day 7 after treatment. The first signs of histological changes were the appearance of cell debris in the ducts and vacuolization of the epithelial cells observed in the proximal caput epididymis on day 1 after treatment. The incidences and grades of the histological changes including cell debris in the ducts, epithelial vacuolization, oligospermia, and epithelial disruption increased on day 2 and then decreased slightly on day 7 after treatment. These results show that a single oral dose of 70 mg/kg ECH to male rats results in cell debris in the ducts and vacuolization of the epithelial cells in the proximal caput epididymis, followed by reversible oligospermia, epithelial disruption, and decreased sperm motility.

Pleurotus cornucopiae (PC) mushrooms are found in the field and commonly known in Japan as Tamogidake mushrooms. The present study investigated the protective effects of an aqueous extract of PC on carbon tetrachloride (CCl4)-induced hepatotoxicity and the possible mechanism involved in this protection including cytochrome P450 (CYP) 2E1. Wistar rats were pretreated with aqueous extracts of PC (0, 100, 200, and 400 mg/kg) orally for 8 days prior to the intraperitoneal administration of a single dose of CCl4 (0.5 ml/kg) or corn oil. Pretreatment with PC mushroom extract significantly prevented the increased serum enzyme activities of alanine and aspartate aminotransferases in a dose-dependent manner, and suppressed the expression of CYP2E1. PC mushroom extract also protected hepatocytes from the damage effects of CCl4 as remarked by histological and electromicroscopical findings. It was concluded that repeated daily doses of aqueous extracts of PC mushroom reduced the toxic effects exerted by CCl4 on the liver.

Results of studies of peculiar properties of progesterone content in blood serum of outbred female rats under the influence of intensive ionizing radiation against the background of stress stimulation realized in the conditions of the Republic of Belarus were presented. There were the following animal groups: 1. controlled rats; 2. irradiated rats; 3. stressed animals; 4. rats subjected to ionizing radiation and stress. Research results showed that concentration of progesterone in serum blood of female rats in 3 days after immobilized stress decreased on 40% in comparison with the control indexes. More intensive decreasing of hormone level took place after irradiation in dose of 1 Gy (on 62% in comparison with the controlled group). Combine activity of ionizing radiation and stress involved the decreasing of hormone concentration on 25% in comparison with the controlled group. In ten days there was the restoration of changes. Increase of progesterone concentration in blood serum took place in all tested groups. Hormone level in blood serum of irradiated rats increased on 46,04 nmol/l in comparison with results of the third day after irradiation. Hormone level in blood serum of stressed animals increased on 11,63 nmol/l, in group subjected to the combined activity of ionizing radiation and stress – on7,65nmol/l. On the thirtieth day the indexes of progesterone concentration in blood serum of irradiated rats, stressed rats and rats subjected to ionizing radiation and stress were almost similar to the control indexes

Investigation of acute and subacute toxicity of formulations of elecampane (Inula helenium) (herbal infusion, tincture, liquid and dry extracts) by the example of experimental white mice of both sexes ( body weight - 18-20 g) and white rats (body weight - 180-200 g) was realized in the conditions of the Republic of Belarus. In course of studies there were analyzed behavior (excitation or depression), physical activity, habitus, appetite, degree of reaction revelation to exogenous irritants, presence of shivering, cramps, paresis, comatose state, time and character of intoxication, dates of animal death). Results of the toxicological experiments showed that the developed preparative forms of elecampane could be referred to the substance hazard category 4, i.e. low-hazardous substances (lethal dose (LD) sub(50) more than 5000 mg/kg live weight). Median lethal dose of tincture was 14043 mg/kg for mice and 12684 mg/kg for rats. Median lethal dose of liquid extract was 13230 mg/kg for mice and 12285 mg/kg for rats

Investigation of acute sub-acute toxicity of preparative forms (herbal infusion, tincture liquid extract and pulvis) of marsh cinquefoil (Comarum palustre) by the example of laboratory animals was realized in the conditions of the Republic of Belarus. White mice of both sexes with body weight of 18-20 g and white rats with body weight of 180-200 g were used in the experiment. Experimental preparations were administrated on empty stomach after 12 hours of absolute diet. The animals were supervised in course of 14 days. All changes in behavior were registered. Calculations of parameters of acute and average toxicity of all analyzed forms were presented. Research results showed that all analyzed preparative forms could be referred to the substances hazard category 4 (low-hazardous substances) with lethal dose 50 more than 5000 mg/kg of live weight. It was determined that the analyzed preparative forms proved to be highly effective against strongylatosis (Strongylata) of gastro-intestinal tract of sheep and calves

Results of studies of acute and chronic toxicity of control samples of long acting boluses on the basis of fenbendazole for the treatment of strongylatosis (Strongylata) of gastro-intestinal tract of cattle realized in the conditions of the Republic of Belarus were presented. White rats and mice were used for studying of acute and chronic toxicity of the prolonged anthelmintic. The preparation was tested in doses of 400; 800; 1200; 1600; and 2000 mg/kg of body weight. Prolonged anthelmintic was administrated introgastrally in the form of suspension. Preparation was reduced to fragments before application. White rats with body weight of 80-100 g were divided in three groups and were used for testing. Bolus of prolonged activity was reduced to fragments and mixed with feed before application. Rats ate the preparation during 30 day in dozes of 250 mg/kg, 375 mg/kg, and 500 mg/kg. Study of acute toxicity of preparation established that LD0 for white mice was 400 mg/kg; LD16 - 620 mg/kg; LD50 - 1080 (1062,7 / 1097, 3) mg/kg; LD84 - 1660, LD100 - 200 mg/kg. Signs of animal toxicosis were revealed in shakiness, depression, whiteness of visually accessible mucous coat, cramps. Catarrhal-haemorrhagic gastroenteritis and numerous effusions of blood on mucous coat of digestive tract were established at postmortem examination. There were no morphological changes in tissues of lungs, heart, liver and nephros. Eating of prolonged anthelmintic with feed during 30 days did not render toxicological influence on rats. There were no signs of intoxication, physiological deviations and no animal death. Research results showed that the analyzed prolonged anthelmintic could be referred the substance hazard category 3