Module VII Flashcards
- Describe suitable housing and husbandry routines for laboratory animals, how conditions are monitored and identify the consequences for the animal resulting from inappropriate environmental conditions.
The aims of housing and husbandry are to meet the regulatory demands, keeping the animals’ comfort and well-being in mind, and control the animal’s environment. This aims to try and control many of the variables such as genetic, microbial, chemical and physical.
Housing and husbandry needs of an animal: space, surface, rest, hide, feel safe, food + drink, company, temperature, air, circadian cycle, possibility to keep clean and dry, activity.
Minimum requirements for environment in the animal rooms (ventilation, temperature, humidity, lighting, noise, alarm systems), health, caging (environmental enrichment, dimensions, food + water supply, bedding material + cleaning, handling).
Air pressure is monitored with hyper pressure in barrier units and hypo pressure for quarantine rooms. Positive pressure rooms maintain a flow of air out of the room thus protecting the animals inside from possible contaminants and pathogens which might otherwise enter. Negative pressure rooms maintain a flow of air into the room, thus keeping contaminants and pathogens from reaching surrounding areas.
Husbandry routine: receiving, marking, cage changing, cleaning, feeding, watering, breeding, weaning, observing, killing.
● Housing in open cages: change once or twice a week, the animals are exposed to allergens and smells.
● Scantainer: for protection of animals (immunodeficient and transgenic) as well as the personnel. All the supply and exhaust air is filtered. Minimises allergens and noise.
● Individually ventilated cages (IVC): airtight animal cage with air supply and exhaust system. Animal room with very few allergens. Animal room that is odor free.
○ Have ventilation units that control air flow, exhaust air flow, temperature, relative humidity, pressure and air changes.
- Describe how the animal facility is organized to maintain an appropriate health status for the animals and the scientific procedures. Do also describe the biological consequences of acclimatisation, habituation and training.
Barrier animal housing is designed and managed to protect the animals from unwanted microbes. Can be at cage level, room level or level of an area within a facility, or the entire facility. Involves autoclaving of cages and material as well as irradiation of food and bedding. The way in which supplies and personnel enter the facility is also controlled.
The animal facility is organized in either a single corridor (uni or bi directional) or dual corridor that have separation between dirty and clean corridors and therefore avoid cross contamination between animal rooms.
Depending on the level of the barrier facility, at the highest level the personnel will shower and change clothes before going in, the supplies will be autoclaved and sterile supplies will go through a chemical lock.
Acclimatization: process in which an individual organism adapts to change in the environment. It allows the animal to maintain performance across a range of environmental conditions. When animals arrive at a facility, they have been transported and at the new place will have to adjust to new social groups and hierarchy; these changes in conditions are associated with effects in physiological symptoms. These effects can confound research if the animals are used in experiments before homeostasis has been restored and physiological states normalize. A period of 1-2 weeks is recommended, but can be longer depending on the transport and strain/age of the rodent.
- Name different methods for marking individual animals and state an advantages and disadvantage for each method.
● Ear tag
○ Advantage: inexpensive and straightforward procedure that is permanent.
○ Disadvantage: may need to use local anesthesia, infection and insertion site, tags can get tangled in cages, etc.
● Ear punch
○ Advantage: simple and inexpensive
○ Disadvantage: the numbers fade after several weeks due to healing and fights between rodents can give rise to similar notches in the ear making individual variation illegible.
● Toe clipping
○ Advantage: simple and inexpensive method
○ Disadvantage: very painful and causes distress to animals, may lead to abnormal gait of animals.
● Tattooing
○ Advantage: permanent animal identification techniques that can be done on very young mice.
○ Disadvantage: needs anesthesia, not useful on pigmented animals, expensive equipment and person has to be trained.
● Freeze marking
○ Advantage: relatively painless and permanent form of branding
○ Disadvantage: not ideal for animals with light coloured hair as the branding would not show up as clear. More expensive than hot branding.
● Hot branding
○ Advantage: permanent way to mark animals.
○ Disadvantage: more painful as the heat destroys layers of skin, also risk of infection and inflammation.
● Microchipping
○ Advantage: little chances of error or tampering are expected.
○ Disadvantage: expensive and some chips may be too big for smaller rodents and neonates.
There are some simple temporary methods to mark the animals like tail marking with a pen, clipping hair, and fur dying. Pen marks last for 1-2 days while hair clipping can identify the subjects up to 14 days.
- List the correct procedures for ensuring health, welfare and care of animals during their transport.
Means of transport used for the road transport of animals for more than eight hours must be checked and approved beforehand by an approved inspection company. Animals must be accompanied by a health certificate, the official veterinarian must in connection with the issuance of this certificate, also certify that, at the time of the examination (within 48 hours of transport), the animals were suitable to be transported on the planned route in accordance with the provisions of the transport regulation. It is the responsibility of the sender or their representative to ensure that the recipient or his representative is informed of the time of the animals’ arrival at the destination and to take care of the animals upon arrival at the destination.
Transport of slightly injured or sick animals, which are not caused unnecessary suffering due to transport, may only take place if the bottom of the means of transport is provided with an extra thick layer of suitable bedding during transport.
For transport lasting longer than 12 hours, however, the animals must be able to stand upright without touching the lid with their heads. At least two of the sides of the box, possibly one of these and the lid, must be provided with wire mesh, bars or ventilation openings, so that ample air circulation is ensured during transport, without the animal’s head or legs being able to pass through the openings. The boxes (baskets) must not be stacked in such a way that the necessary air circulation is obstructed.
- List potential human health hazards associated with contact with laboratory animals and how these can be prevented
● Allergy (LAA, laboratory animal allergy)
○ Protein allergens include lipocalin superfamily, albumin, prealbumin, alpha 2 macroglobulin.
○ Development of skin allergy requires a sensitisation phase (induction) which lasts 10-14 days and then there is elicitation upon re-exposure to allergen and this lasts 12-48 hours.
○ Symptoms of allergy include hay fever, asthma, skin reactions, anaphylactic shock.
○ Diagnosis is related to the exposure: symptoms at work, improvement during vacation, skin testing and allergy blood testing.
○ Allergy management:
■ Reduce levels of allergens: use isolation cageing, keep animal density down, use correct bedding material, ventilation related separation, increased humidity.
■ Reduce contact with allergens: protective clothing, restrictions of access to animal facilities, separate animal work from other work, clean/dirty areas, reduce the number of exposed persons.
■ Monitor allergen levels.
■ Educate people.
○ Treatment: medication like antihistamines, bronchodilators and steroids. Or can also do immunotherapy.
● Physical injuries
○ Bites and scratches: need to see if they are infectious or noninfectious. Can avoid these by learning how to handle animals using proper restraint. Treat depending on the size and depth of the bite.
○ Sharp objects such as needles, scalpels and glass pipettes.
● Harmful substances
○ Biologicals (include infectious agents used for experiments, cells and toxins). Only open the cage in a safe area, wear PPE, good needle practice, disinfection/autoclaving of waste.
○ Radioactive isotopes: keep and transport radioactive substances safely, prepare syringes before experiments, restrain animals properly, inject in a safety cabinet, use personal protection, keep animals enclosed, handle waste properly, etc.
○ Adjuvants
○ Chemicals
■ Dangerous chemicals used in experiments, inhalation anesthetics and pressure bottles (gas release from these can lead to uncontrolled rockets or pinwheel).
● Zoonoses:
○ Bacteria, viruses, fungi and parasites
○ Different animals carry different zoonoses, other sources of zoonose include cell lines, tissue cultures, transplants, biological products.
○ Common routes of exposure to zoonoses include ingestion, inhalation, inoculation and contamination of skin and mucous membranes.
○ Prevention: microbiologically defined animals, biological products from safe sources, barrier units in animal facilities, good working routines, adequate PPE, and actions in case of accidents.
○ If there is injury, symptoms to look out for include local inflammation, flu-like symptoms, conjunctivitis, vomiting, diarrhoea, rashes, shaking, joint pain, etc.
