EN
Genetically modified organisms are increasingly used in the production of feed and food, which has met with opposition from consumers. The aim of the study was the use of molecular biology methods with particular emphasis on techniques of real-time PCR in the research in the detection and identification of genetically modified feed. The research materials were samples of feed taken from feed produced and used in animal nutrition in Poland in the years 2004-2015. The applied research methods included PCR and real-time PCR techniques, and consisted in the detection and determination of the DNA content of genetically modified plants. Cascade methods used in this study included the screening method of detection of GMOs, the method of identifying the type of GMO, and methods of quantitative analysis of GMO content. As part of the research task in the years 2004-2015 a total of 1435 samples of feed towards GMOs were examined. A positive result was found in 559 cases (39%). Most frequently the positive samples were found the presence of genetically modified soybeans (531, 37%). Moreover, within the years 2014-2015 an increase in the number of positive GM rape samples was observed (56, 4%). GM maize contained the least positive samples (38, 2.6%). GMO content above the legislative threshold 0.9% was found in the vast majority of samples containing GM soy, while for maize and rapeseed the number of samples containing more than 0.9% GMO was respectively 12 and 8. Analysis of the feed market in Poland indicates that the soybean plant is the most common genetically modified crop. Analysis of the origin of sources of GM rapeseed showed that the reasons for this should be sought in batches of rapeseed imported from third countries. It has been observed with regard to the situation of GM maize for the feed market in Poland that from 2013 the situation changed radically as a result of the Decree of the Ministry of Agriculture issued prohibiting the cultivation of MON810 maize on Polish fields. The result of our study showed that the proportion of genetically modified feed on the feed market in Poland is very similar to other EU countries. The source of GMOs in feed on the Polish market is feed materials imported into Poland as a source of feed protein.