While there are many European scientific activities for each of the items related to either animal health or the occurrence of GM ingredients in animal feed, the proposed MARLON project will be unique in bringing these widely different fields of scientific expertise together for the cross-disciplinary task of developing an epidemiological model for the case-specific monitoring of potential health impacts of GM animal feeds in livestock.More specifically, the proposed MARLON project will create an inventory of which epidemiological and monitoring initiatives exist, both within and outside the EU, which could provide useful data for the purpose of monitoring for health impacts of animal feeds, in particular those containing GM ingredients, on livestock animals. It will also collate, in a systematized manner, information on the factors that have to be considered when developing an epidemiological model specifically geared towards this purpose. These factors include 1) the possibility to determine the exposure of animals to GM feed ingredients, 2) the health indicators that have to be considered for particular cases of health impacts identified during pre-market risk assessment of the GMOs, 3) the characteristics of the animal feed and livestock production chains. The project also will develop an epidemiological model specifically geared towards establishing links between measured health effects in livestock and their intake of GM ingredients from animal feed.As previously stated, there are many activities in the EU focusing on the specific items that together constitute the cross-disciplinary research within the proposed MARLON project, but so far none of them has done this in its totality for the specific purpose of linking health impacts in livestock to GM feed consumption.The proposed MARLON project is to take stock of these initiatives and assess the applicability of the data collected and/or generated by them for the purpose of case-specific monitoring.