ALAT Animal Husbandry and Environment Questions and Answers 1 — Questions and Answers
Question 1: Which of the following environmental factors is considered a component of the macroenvironment in an animal facility?
- Bedding material inside a mouse cage
- The light intensity and cycle in the animal room (Correct answer)
- The social structure within a group-housed primate enclosure
- The temperature and humidity within a specific microisolator cage
Correct answer: The light intensity and cycle in the animal room
The macroenvironment refers to the larger environment of the animal room itself. This includes factors like the room's temperature, humidity, ventilation, and light cycle, which affect all enclosures within that space. The other options describe aspects of the microenvironment, which is the immediate environment within the animal's primary enclosure.
Question 2: A newly hired ALAT is instructed to disinfect a surface that has been contaminated with organic material. What is the essential first step they must take before applying the disinfectant?
- Rinse the surface with hot water to kill initial microbes.
- Apply a concentrated bleach solution to the organic material.
- Mechanically remove the organic material and clean the surface with a detergent. (Correct answer)
- Allow the surface to air dry completely to weaken the contaminants.
Correct answer: Mechanically remove the organic material and clean the surface with a detergent.
Disinfectants are often inactivated by the presence of organic material like feces, urine, or bedding. Therefore, it is crucial to first physically remove all visible debris and then wash the surface with a soap or detergent to eliminate any remaining organic residue before applying the disinfectant for the recommended contact time.
Question 3: An animal technician observes that a room housing mice has a humidity level of 85%. According to the 'Guide for the Care and Use of Laboratory Animals', why is this a concern?
- Low humidity can cause ringtail in rats and respiratory issues.
- High humidity has no significant effect on rodent health.
- The ideal humidity range is between 10% and 20%.
- High humidity can lead to increased microbial growth and animal discomfort. (Correct answer)
Correct answer: High humidity can lead to increased microbial growth and animal discomfort.
The generally accepted range for humidity in rodent housing rooms is 30% to 70%. Humidity levels above this range, such as 85%, can contribute to the growth of mold and bacteria, create an uncomfortable environment for the animals, and may affect experimental outcomes.
Question 4: Which of the following is the BEST example of environmental enrichment aimed at promoting species-specific behavior in rodents?
- Playing loud music in the animal room during the light cycle.
- Providing deep bedding and nesting material. (Correct answer)
- Housing mice in individual, barren cages to prevent fighting.
- Keeping the room lights on 24 hours a day to facilitate observation.
Correct answer: Providing deep bedding and nesting material.
Rodents have a natural, species-specific instinct to burrow and build nests. Providing deep bedding and materials like cotton squares or paper strips allows them to perform these behaviors, which enhances their well-being and reduces stress. The other options are examples of poor husbandry practices that would likely cause stress.
Question 5: A research protocol requires that mice be housed in static microisolator cages. To ensure proper animal welfare and a stable microenvironment, how often should these cages typically be changed?
- Every 28 days to minimize animal stress.
- Only when they become visibly soiled.
- At least once every two weeks (biweekly). (Correct answer)
- Daily, to provide a completely sterile environment.
Correct answer: At least once every two weeks (biweekly).
The 'Guide for the Care and Use of Laboratory Animals' suggests that solid-bottom caging for rodents, such as static microisolators, should be changed at least once or twice a week. Institutional guidelines often specify a maximum of 14 days (biweekly) between changes for mice in ventilated systems, but static cages may require more frequent changes due to ammonia buildup. Biweekly is a common maximum interval under ideal conditions.
Question 6: What is the primary reason for maintaining a negative pressure differential in an animal quarantine or infectious disease room?
- To ensure air flows from the hallway into the room, preventing contaminants from escaping. (Correct answer)
- To increase the number of air changes per hour within the room.
- To make the room warmer and more comfortable for recovering animals.
- To ensure air flows from the room into the hallway, pushing clean air towards other colonies.
Correct answer: To ensure air flows from the hallway into the room, preventing contaminants from escaping.
A negative pressure room has lower air pressure than the surrounding areas. This causes air to flow from the cleaner area (the hallway) into the potentially contaminated room when a door is opened. This airflow helps contain airborne pathogens and allergens within the room, protecting animals and personnel in other parts of the facility.
ALAT Animal Husbandry and Environment Questions and Answers 1
Which of the following environmental factors is considered a component of the macroenvironment in an animal facility?