STUDY ON THE MICROSCOPE METHOD AND THE VIEW OF THE ANALYTICAL TECHNIQUES FOR IDENTIFICATION AND ESTIMATION OF THE PROCESSED ANIMAL PROTEINS IN ANIMAL FEED Magdalena TRANDAFIR, Horia ALBU, Rodica TANASUICA, Laurentiu CIUPESCU Institute for Hygiene and Veterinary Public Health Bucharest, Romania, No 5, Câmpul Mo ilor, Code 021201, Bucharest, Romania, phone: 0212524651 Corresponding author email: magdalena.trandafir@iispv.ro Abstract Hypothesis universally accepted as the most likely route of infection with ESB appeared due to the consume of the animal by-products which are not intended for human consumption that contained prion protein derivative - infected led to ban the feeding of farmed animals with processed animal protein (PAP) that focused primarily feed for ruminants and later expanded to all feed for all farm animals. Entry into force of the ban on the use of the processed animal proteins (PAP) in feed for farmed animals and especially in ruminants is considered an important measure of prophylaxis to prevent BSE so the identification and the microscopic estimation of the constituents of animal origin became the official method and mandatory in all Member States. The microscopic analysis depends upon the identification of the hsitological characters macro-and microscopic structural of the processed animal tissue added in feed mixtures.To identify the microscopic animal constituents, some technical conditions are essential: optical microscope, stereo microscope, high-density solvent (chloroform or tetrachloroethane) clarifying agents (phenol-glycerol, paraffin), microscope with digital visual images support as decision support . The method allows the identification of bone fragments, muscle tissue, hair, feathers, shell fragments and plant and mineral components. Nowadays four different approaches are applied to control the compliance on the prohibition of feeding with PAP: microscopic analysis, immunological analysis, infrared spectroscopy and microscopy (NIR), polymerization chain reaction (PCR). In this stage, the microscopic method is the only method validated and able to identify the nature of the animal in feed components with detection limit of <0.1%, but it cannot accurately detect the species of origin. Key words: feed, microscopic identification, polymerization chain reaction, processed animal proteins, transmissible spongiform encephalopathy. INTRODUCTION So far it has been shown that animal by- products not intended for human consumption, resulting in a row processing, more or less correct, cadavers, products and by-products from animals, constituting a potential source of risk to public health and the animal. This way the probable infection with prionic protein derivative-infected, has led to a ban on the feeding of farm animals with processed animal proteins (PAP) which focused primarily on feeding stuffs for ruminants, and was subsequently extended to all feed for all farm animals. Safety use of proteins derived from animals in feed at European level constitutes an important decision factor in the prevention of transmissible spongiform encephalopathy’s (TSEs). Properties of infectious agents of TSEs have proven to be very unusual. Infectious agents of TSEs, manifested in humans or in animals are actually made from a single type of protein called PrP Sc , are devoid of nucleic acids. Use of protein meat-and-bone type as an ingredient in animal feed is regulated according the European legislation (Commission Decision 97/534/EC) since 1997, and effective heat treatment to which they are subjected has been set to, 3 bar, 133 o C, 20 minutes (Regulation (EC) no 1069/2009). European regulations prohibit feeding of animals of farm intended for human consumption, intraspecie with proteins derived. Considering the fact that the methods of analysis for protein supplements have carried out a series of inconveniences in selectivity (in particular for the identification of protein derived from ruminants) the ban was extended for proteins derived from all 116 Scientific Works. Series C. Veterinary Medicine. Vol. LX (2) ISSN 2065-1295, ISSN Online 2067-3663, ISSN CD-ROM 2343-9394, ISSN-L 2065-1295