Autologous biologicals--science/regulations

There has been increased interest in Targeted Biologicals in the United States for several reasons. First, new technology is available to facilitate science-based isolate selection and manufacture. The science of Autologous/Targeted Biologicals will be discussed later in this presentation. A second reason for the increased interest in Targeted Biologicals is the fact that the livestock production methods have changed to favour herd/flock specific products controlled by a veterinarian. There have been changes in management methods such as segregated early weaning in swine, accelerated feeding and early weaning of dairy calves, and forced moulting in poultry. Herds and flocks have increased in stocking density and size. These factors stress animals and may facilitate mutation, strain variation and increased virulence of pathogens. Under these conditions, Traditional Biologicals may not be relevant to current field isolates. Many veterinarians favour vaccinating only for pathogens isolated from a herd/flock. A third reason for the increased interest in these products is that the licensing procedure for Targeted Biologicals is responsive to the needs of livestock producers. The process is abbreviated, requiring much less time and money. This allows for a more rapid response to emerging pathogens, strain variations and mutations, while facilitating the development of monovalent and multivalent products for limited markets or those for minor species.