"We did not add anything for one group but the other was fed with soya that contained no GM components, while the third group with some content of Genetically Modified Organisms and the fourth one with increased amount of GMO. We monitored their behavior and how they gain weight and when they give birth to their cubs. Originally, everything went smoothly. However, we noticed quite a serious effect when we selected new pairs from their cubs and continued to feed them as before. These pairs’ growth rate was slower and reached their sexual maturity slowly. When we got some of their cubs we formed the new pairs of the third generation. We failed to get cubs from these pairs, which were fed with GM foodstuffs. It was proved that these pairs lost their ability to give birth to their cubs"