Module V

Question 1

1. Discuss potential disease risks in the animal facility, including specific predisposing factors which may be relevant, and describe methods available for maintaining appropriate health status

Answer 1

Microorganisms in laboratory animals may be zoonotic, meaning that they can infect humans and eventually cause disease, they may cause disease in animals, or they may interfere with research in other ways. However, there are also certain bacteria which are important for the models you want to induce in the animals. Disease can be fulminant, meaning you can see the disease (there are clinical symptoms). Disease can also be latent, that means you cannot see the infection (there is no clinical expression). So, infections may cause disease, but infections do not always cause disease. However, infections not causing disease may interfere with animal research in other ways.

Breeding colonies of laboratory animals are set up after rederivation. That means, that the ancestor breeders have been produced either by caesarian section or embryo transfer by which methods you can make infection free animals. Then, they are placed in facilities in which they can be protected, either behind a barrier or in isolated surroundings. To be sure that these animals are still without infections, we do routine health monitoring.

● Health monitoring (routine sampling of healthy animals to detect the health status of the breeding colony)
○ The Federation of European Laboratory Animal Science Associations has issued recommendations for health monitoring of various species. They list which agents they consider relevant to test in those animal species and how frequently this should be done.
■ Do certain assays on various samples from the animals. They inspect the pelt and the skin under a microscope for ectoparasites, they will do serology on serum for antibodies to viruses but also for antibodies to some other agents. They will look for bacteria in the genitals, in the ileum, in the caecum, in the trachea and in the nose, for instance, and they will look for parasites in the feces.

Question 1

2. Describe how the animal facility is organized to maintain an appropriate health status for the animals and the scientific procedures

Answer 1

The animal facility is organized by three steps to maintain appropriate health status for the animals.
1. First step is rederivation. The breeding colonies of laboratory animals are set ud after rederivation. That means, that the ancestor breeders have been produced either by caesarian section or embryo transfer by which methods you can make infection free animals.

2. Second step is protection. The animals are now placed in facilities in which they can be protected, either behind a barrier or in isolated surroundings.
   * Conventional: no ventilation, you don’t have any restrictions on staff entrance, there are no quarantine rules, you do not decontaminate materials, and the microbiological protection you achieve that is completely insecure.
   * Barrier: The air is ventilated with filters in the inlet and in the outlet. The staff will have to enter through a three-room shower, and they will have quarantine if they have had contact with other animals of the same species. Materials need to be passed through an autoclave or a chemical disinfection lock, where you spray them with chemicals, and the protection you obtain is that the animals can be kept free of species-specific agents, but, of course, they will typically harbor microorganisms that they share with humans, because you still have the human caretakers behind the barrier. You call these animals microbiologically defined or sometimes you also call them Specific pathogen free (SPF).
3. Third step is health monitoring (routine sampling of healthy animals to detect the health status of the breeding colony). The Federation of European Laboratory Animal Science Associations has issued recommendations for health monitoring of various species. They list which agents they consider relevant to test in those animal species and how frequently this should be done.
   * Do certain assays on various samples from the animals. They inspect the pelt and the skin under a microscope for ectoparasites, they will do serology on serum for antibodies to viruses but also for antibodies to some other agents. They will look for bacteria in the genitals, in the ileum, in the caecum, in the trachea and in the nose, for instance, and they will look for parasites in the feces.