1 Management of Immunocompromised and Infected Animals

Area of Science:

• Laboratory Animal Science
• Microbiology
• Reproductive Biology

Background:

• Microbiological quality of laboratory animals is dependent on colony management.
• Monitoring assesses the adequacy of management practices.
• Comprehensive microorganism monitoring is essential for immunocompromised animals and infection experiments.

Purpose of the Study:

• To discuss the management of immunocompromised and infected animals.
• To outline microbiological monitoring strategies for laboratory animals.
• To detail embryo cryopreservation and revitalization protocols for establishing breeding nuclei.

Main Methods:

• Necropsy, blood sampling for serology, and microscopic examination for parasites.
• Organ sampling for bacteriology, pathology, and virology.
• Cryopreservation of preimplantation embryos (eight-cell stage recommended) and assessment of revitalization rates.

Main Results:

• Biological materials from animals pose a high contamination risk, especially passaged tumors, viruses, or parasites.
• Preimplantation embryos (mice and rats) can be successfully revitalized after freeze-thaw.
• Eight-cell stage embryos are recommended for long-term storage over two-cell stages.

Conclusions:

• Rigorous colony management and comprehensive monitoring are key to maintaining laboratory animal quality.
• Standardized embryo cryopreservation protocols ensure the establishment of breeding nuclei.
• A minimum of 10 embryos per batch is recommended for a 50% chance of obtaining a fertile breeding pair, assuming a 20% revitalization rate.