Mouse metaphase two (M two) oocytes were exposed to 50 mug/ml etoposide (ETO) before and after parthenogenetic activation with 7% ethanol and they were washed with 0.75 M sucrose. The ETO treated parthenogenetically activated oocytes were cultured or fused to single blastomeres of late 2-cell stage mouse embryo to test their ability to support development in vitro. In parallel untreated parthenogenetically activated oocytes were cultured to serve as control. None of ETO treated oocytes developed beyond the 2-cell stage, whereas 4% of the reconstituted embryos and 35% of control developed to blastocysts. It is concluded that mouse M two oocytes can be functionally enucleated by ETO treatment and can be used for nuclear transfer experiments

The protective effects of high levels of dietary iron, copper, zinc or protein on lead toxicity were studied in chicks. Growth retardation, reduction of feed intake, anemia and accumulation of lead in the bone and kidney were observed in chicks fed a diet containing 500mg lead as chloride/kg of feed for 42 days. Early changes due to ingested lead were inhibition of red blood cell 8-aminolevulinic acid dehydrase at all doses and no effect of iron, copper, zinc or protein addition were observed

The methods and results of determination of safety and relative biological value of carps (Cyprinus carpio) with philometroidosis and breams (Abramis brama) with ligulosis depending on infestation intensity with application of test-object Tetrahymena pyriformis realized in the conditions of the Republic of Belarus were presented. Research results showed that lowering of reproduction degree of protozoan on 20-30% could testify to the presence of light toxicity. Suppression of infusoria reproduction up to 30% with the simultaneous lowering of actions activity, disturbance of its character and availability up to 10% of inflected cells could testify on the moderate degree of toxicity. Lowering of infusoria reproduction degree on 30-50% with the simultaneous presence of 10-20% of cells with the affected character of motion, form and dead testified to evident toxicity of products. Lowering of infusoria toxicity on 50% and higher, presence of cysts, distorted cells, and ghosts testified to high product toxicity. Research results established that in case of high invasion intensity meat of carp philometroidosis had low toxicity (2 points). Meat of breams with ligulosis and moderate invasion intensity had low toxicity level (2 points), and in case high invasion intensity – moderate (3 points). The relative biological value in case of philometroidosis was on 13,29-28,41% lower in comparison with meat of healthy carps, and in case of ligulosis - on 18,66-57,29% in comparison with healthy breams meat