The study of pesticide and VD residues in animal feed is an important issue because they can reach the food chain. On the one hand, animal feed is usually employed to administer drugs to animals [7] and, on the other hand, they can be prepared with several ingredients, which are not always free of pesticides [3]. Consequently, in order to ensure animal safety, the European Union (EU) has established regulations for the control of residues in feed, setting maximum residue limits (MRLs) for pesticides [8] and VDs [9, 10]. Moreover, Regulation (EC) 1831/2003 banned the use of all antibiotics other than coccidiostats and histomonostats as feed additives (used as growth promoters) since 1 January 2006. Furthermore, these products have been completely banned on December 2012 [11]. Thus, VDs should be strictly applied for the prevention or treatment of diseases. In this way, these regulated limits require the determination of an extremely high number of VD and pesticide residues in feed with the aim of ensuring their use in a rational and safe way.