Chapter Eight

1. Chapter Eight Laboratory Animal Environment

2. ALAT Presentations Study Tips • If viewing this in PowerPoint, use the icon to run the show (bottom left of screen). • Mac users go to “Slide Show > View Show” in menu bar • Click on the Audio icon: when it appears on the left of the slide to hear the narration. • From “File > Print” in the menu bar, choose “notes pages”, “slides 3 per page” or “outline view” for taking notes as you listen and watch the presentation. • Start your own notebook with a 3 ring binder, for later study!

3. Environment, Equipment, & Hygiene • Standards, equipment & procedures • safety & potentially hazardous problems • Animal facility commonly located in building or wing separated from labs & offices. • Facility = animal rooms, cage wash, offices, locker rooms, storage, surgery suites & other rooms. • Environment (temperature, humidity, noise & air exchange) evaluated for level & consistency. • Animals outdoors need protection from heat, cold & other environmental extremes.

4. (Image) Animal Facility Corridor

5. Animal Rooms • Conventional = no special precautions to prevent introduction of disease • Feed, groom & vaccinate against diseases • don’t keep in special room to isolate • Larger animals in conventional cages & rooms • Barrier = special cages & procedures practiced • A barrier = cage, a room or even entire facility • Temperature, humidity, ventilation, light, noise & other variables in room affect environment. • Direct effect on behavior & health which impacts data. • The Guide provides table of recommended temperature levels for common laboratory species.

6. Temperature & Humidity • Too hot or too cold can induce stress in animals. • In rodent breeding room, ~ 72°F suitable for neonates • Newly-hatched chicks or hairless rodents, & post-operative recovery = warmer end of range. • Newly-hatched chicks & very young pigs may require an extra heat source. • Temp > 80°F, adult mice may suffer heat stress. • Humidity = amount of moisture in air. • Range of relative humidity is 30–70%. • Low humidity = ringtail & respiratory problems. • High humidity = respiratory problems & food spoilage.

7. Ventilation • Ventilation helps eliminate noxious odors. • ammonia = by-product of breakdown of urine • The Guide: 10 -15 exchanges of fresh air/hour. • Recirculated air filtered to remove contaminants. • Room is under + or – pressure. • + pressure rooms = > pressure than surroundings • Opening a door causes air to flow out toward the hallway. • Surgical suites, barrier rooms under + pressure. • - pressure rooms = < pressure than surroundings • Opening a door causes air to flow into the room. • Quarantine and conditioning & rooms to contain hazardous agents under – pressure. • Check air pressure regularly to be sure correct.

8. Lighting • Lighting evenly distributed & bright enough • Change = stress & affects breeding efficiency. • Turn lights on or off at prescribed times. • Check lights on automatic timers. • Long exposure to bright light = problem for albino. • Research may call for specific light/dark cycles. • Natural light varies & interferes w/ controlled light. • Some systems permit changing light intensity. • Lower level used to maintain animals. • Level temporarily increased for room cleaning & maintenance.

9. Noise • Certain rodents, cats, guinea pigs & rabbits react negatively to noises. • Rabbits may jump & injure self, rodents may not breed. • Noise may alter hormone levels. • Technicians should avoid making loud noises (shouting or banging cage doors). • Radio may be played to provide low-level background noise, reduces startle response. • Speech in comforting tones to noise-sensitive animals may calm them. • House these animals away from noisy animals, activities & busy areas.

10. Animal Room Construction • Ideal animal room allows easy cleaning. • Non-slip, waterproof floors & drain covers prevent debris from going into sewer. • Floors are sloped toward drains. • Walls and ceilings made of sealed material • waterproof & easy to clean • surfaces free of cracks, chipped paint & vermin-proof • moisture-proof & vermin-proof recessed fixtures & outlets • Doors self-closing, with a view port, kick plate, locks & recessed handles. • Dimensions are a minimum of 42 inches X 84 inches.

11. Barrier & Containment • More sophisticated rooms • Designed to prevent entry of disease or disease in- side room from getting out. • Shower and wear special protective clothing. • Cages, bedding, food & water sterilized before entering room to prevent introduction of disease. • SPF = animals do not have certain diseases. • Barrier rooms have standard design features, but they have a filtered air supply. • Air passes through a HEPA filter to remove dust & particles from air.

12. Hallways and Traffic Patterns • High traffic areas & require durable construction. • Bumper guards on walls and corners help protect surfaces from becoming chipped and marred. • Recommended hallway width of 6–8 feet. • Double-door airlocks at end of hallways help reduce noise, odors & possible contamination. • Doors that open inward prevent collisions. • Fixtures recessed into wall facilitate equipment movement.

13. (Image) Animal Facility Hallway

14. Hallways and Traffic Patterns II • Single hallway w/ all rooms off same hallway = clean & dirty cages through same area. • In clean/dirty system animal room has 2 doors: • 1 - entering from clean hallway • 2 - leading into the dirty hallway • Prevent dirty from contaminating clean • Enter room from clean, exit by dirty hallway. • Disinfect shipping boxes prior to entering facility. • Disinfect or autoclave supplies before entering barrier. • To work, staff must abide by design requirements.

15. Facility Security • Vandalism & theft add to cost of research by destroying years of effort & wasting animal lives. • Door locks, computerized card entry system • After opening security doors, check that they have been relocked. • Never give unauthorized people keys, access cards & door combinations • Find out who stranger is by asking, “How may I help you?” • Advise supervisors immediately of presence of unauthorized people.

16. Cage Washing Rooms • Cage washing activities are noisy. • Locate areas away from animal areas & offices. • Ventilate areas well to remove steam & odors. • Seal all electrical outlets, light fixtures, walls, floors & ceilings to allow proper cleaning. • prevent water & moisture from penetrating

17. Quarantine, Conditioning & Isolation • Quarantine area separates incoming animals from animals already in the facility. • During quarantine, personnel perform health status evaluations & monitor for disease. • While in quarantine area, animals adjust to new surroundings, referred to as conditioning. • Can be constructed as specialized cubicles • each cubicle equipped w/ negative-pressure air supply • Isolation for animals known or suspected of carrying disease • Isolation rooms operate on negative pressure air supply.

18. Feed and Bedding Storage • Must be vermin-proof & dry • Feed & bedding stored on shelves or pallets, away from walls. • Cool temp and low humidity avoid spoilage. • Separate storage areas designated for clean equipment. • Do not store disinfectants & chemicals w/ clean equipment, feed or bedding. • Hallways, corridors & animal rooms should not be used as storage areas. • Items obstruct traffic flow, accumulate dirt and can be a safety hazard.

19. Personnel & Procedure Areas • Personnel Areas: offices, lunch rooms, showers & locker rooms • Lunch & office areas are only place in which eating & other break activities are permitted. • Procedure rooms - investigators & technicians perform experimental or therapeutic procedures • Performing procedures in animal room may alarm other animals. • Contain examining tables for diagnostic or experimental work & some storage space.

20. Emergency Back-up Power • Without ventilation, air conditioning or heat = no fresh air in the facility. • Causes temperature and ammonia levels to rise • Prolonged high levels of ammonia or carbon dioxide can have serious effects on animal health. • Loss of negative air pressure is a serious problem in quarantine and containment areas.

21. Hazardous Agents • Use of materials or procedures that present a physical, chemical, biological or radiological hazard • Document potential problems & precautions before any research involving hazardous agents. • Signs & notices of hazard type must be posted where hazardous agents are being used. • Contaminated animals or wastes disposed of in areas bearing biohazard symbol. • ALWAYS ASK FIRST & proceed only when confident proper procedures are being followed.

22. Radioisotope Hazards • Radioisotopes emit low levels of radiation, which makes them valuable in studies of processes such as digestion. • Radioisotopes are usually dangerous only if contacted directly; some require stringent precautions & safety measures. • Radiation monitoring badge records exposure and is worn by staff working with radioisotopes. • Institutions using radioactive materials must conform to federal NRC guidelines.

23. Pathogen Hazards • Infectious bacteria, viruses, fungi or parasites that pose a threat to humans and animals • Some can cause disease in humans and may be present in research animals that are not SPF. • Pathogens are utilized for research studies. • i.e. developing tuberculosis vaccine • CDC publishes guidelines for handling organisms & infected animals. • Guidelines outline biosafety levels depending on degree of danger to humans. • Biosafety levels graded from 1 to 4. • BSL 1 is least & BSL 4 most hazardous. Diagram of HIV virus

24. Mutagen, Carcinogens & Toxin Hazards • Mutagens cause changes in chromosomes. • Induce occurrence of mutations. • Carcinogens can induce cancer directly. • Dilute formaldehyde (formalin) tissue preservative. • Toxins are poisonous substances. • i.e. formaldehyde and gas anesthetics • Toxins can also be produced by bacterial, plant or animal cells. • Organism that causes tetanus produces a toxin which is responsible for symptoms.

25. Hazard Containment • Following features help contain hazards: • + and - air pressure differences • Filtration of exhaust air • Airlocks and pass-through autoclaves • Ultraviolet light to destroy organisms on surfaces • Change and shower rooms • Intercom systems between areas • Treatment of contaminated sewage • Back-flow check valves in main water supply lines • Separation between containment & utility systems • SOP for each specific biohazard under study • Covers proper use of PPE

26. Dead Animal Storage & Disposal • Place in plastic bags & either freeze or refrigerate until destroyed or removed. • Plastic or metal cans used for storing carcasses should be leak proof & have tight-fitting lids. • Store only dead animals in these units • Incineration is safe & sanitary means of disposal. • If animal is found dead, notify supervisor who will notify veterinarian & PI. • May perform necropsy & take certain tissues from animal before disposal. • Clearly label carcass & place in refrigerator until a necropsy can be performed.

27. Caging - The Microenvironment • Animals must be able to move freely & have access to clean food and water. • SOPs describe housing standards & care. • Adhering to space recommendations allows animals to have enough room to make normal postural adjustments. • Too many animals or cages that are too small causes stress. • affect physiology, behavior & research data • Crowding is both inhumane & against the law. • USDA’s AWA & The Guide provide specific guidelines.

28. (Image) Various Types of Caging

29. Bedding • Bedding = an absorbent in waste collection pans & material in direct contact with animals. • Cage design determines what type of bedding is used; direct or indirect bedding. Too much Too little Just right

30. Bedding II • Characteristics of good bedding material are: • No ideal material for all species in all applications. • ground corn cob, wood shavings, compressed paper & straw • All bedding products create a certain amount of dust & can clog spray jets in cage washers.

31. Additional Reading Biosafety in Microbiological and Biomedical Laboratories. HHS Publication No. (CDC) 93-8395. 3rd. Edition US Government Printing Office, Washington, D.C. 1993. Guide for the Care and Use of Laboratory Animals. National Academy Press, 1996.