Health assessment for laboratory rodent production colonies.

Unhealthy laboratory animals cause not only serious damage in production efficiency but also undesirable changes in animal quality with a high possibility of occurrence of overt diseases during animal experimentation. Most rodent production colonies now use a strict barrier system which protects animals from the introduction of infective agents. However, routine monitoring of the health status in production colonies is required because conventional environments are still common in fields of animal experimentation during which disease control is much more difficult. Disease problems seem to be more serious in testing or research colonies which receive clean, susceptible animals from production colonies. To develop an effective program for health monitoring and control, particularly concerned with infectious diseases, it is indispensable to accumulate more scientific information on the epizootology of rodent diseases with cooperation between both animal production and experimentation.