From 2,373 slaughtered pigs examined, 1,899 of them had visible evidence of pulmonary lesion. The lungs with pulmonary lesion were examined by grossly, histopathological technique to investigate the prevalence accordint to season, severity ofpulmonary lesion, types of the pneumonia and relationship between rearing management and prevalence of pulmonary lesion. The results were as follows: 1. Prevalence of pneumonia according to season was 72.3 % to 85.9% and the higher prevalence was in winter. 2. In the severity of pulmonary lesion, rates mild, moderate and severe lesions were 38.3%, 47.0% and 14.7%, respectively. Prevalence of mild lesion was the highest in autumn. Prevalence of moderate and severe lesions was the hihgest in winter. 3. In the type of pneumonia, rates of interstitial pneumonia and bronchopneumonia fibrinous pneumonia were 23.6%, 13.0%, and 3.4%, respectively. Prevalence of interstitial pneumonia was high in spring and autumn while that of broncho-pneumonia and fibrinous pneumonia was high in winter and summer, respectively. 4. In relationship of pulmonary lesions according to severityo fpulmonary lesion and types of pneumonia, similarity was observed in prevalence of mild lesion and bronchopneumonia.

The study was designated to investigate the electron microscopic findings following diethylnitrosamine (DEN) treatment in rats. Forty four male (Srague Dawley) rats were continuously given water containing 0.01% DEN for 13 weeks and livers of five rats with more tumor lesions at 16 and 17 weeks after initial treatment were used as EM materials. In transmission electron microscopic findings, most small-sized hepatocytes were active cells containing large mount of organelles, but light (pale staining) hepatocyte among small-sized hepatocytes were injured cells containg disorganized organelles. Tumor cells among small-sized hepatocytes were irregularly arranged and have ;leomorphic nuclei containing electron dense chromatin but the organelles in cytoplasm were swelled. Large-sized hepatocytes were active cells with condensed chromatin but the cytoplasm of these cells were pale due to be injured and dilated organelles. Dark hepatocytes were apoptotic cells with homogenous pyknotic nuclei and cytoplasm, and the cytoplasm of these cells contained dilated smooth endoplasmic reticulum (sER) but these sER were non-vesiculated. Cholangiocarninoma cells were crowed and were pale by far less number of organelles in cytoplasm and nuclei. In scanning electron microscopic findings, the lumens of portal veins, bile canaliculi, bile ductules, bile ducts and sinusoids were dilated and have irregular folded inner surface by protruded parenchyma.

Anatomical and histological changes were studied in the dorsal, ventral, third and splenic lobes of the pancreas of the chicken embryos (8 days of incubation, 10 days of incubation to hatching). From 13 days of incubation, all four pancreatic lobes, namely, dorsal, ventral, third and splenic lobes were observed. Histologically, the pancreas of 10-14 days of incubation were consisted of mesenchymal tissue, exocrine acini and pancreatic islets. But mesenchymal tissues were disappeared from 15 days of incubation. The pancreatic ducts were observed from 14 days of incubation. The dark and light typed pancreatic islets were observed in splenic lobe from 13 days of incubation, in the third lobe from 11 days of incubation, and in the dorsall lobe from 13 days of incubation. But no dark typed islets were observed in the ventral lobes.

Studies of morphological and morphometrical particularities of rennet of newborn calves with different degree of antenatal hypotrophy were realized in the conditions of the Republic of Belarus. Scientific-and-production researches were spent in 2007 - 2008 on the basis of agricultural production co-operative Dembrovo (Shchuchinskij district, Grodno area, Belarus), agricultural production co-operative Okhovo (Pinsk district, Brest region, Belarus) and research laboratory of Grodno State Agrarian University (Belarus). For an estimation of morphofunctional maturities there were used 165 1-day old calves. Research results showed that in the studied calves the basic indexes of glanderous apparatus of rennet proved the different degree of morphofunctional immaturity. In calves with hypertrophy in the first days after birth there stated an active morphogenesis of all cytological components of rennet