PREPARING FOR THE ASSISTANT LABORATORY ANIMAL TECHNICIAN (ALAT) CERTIFICATION EXAM

Chapters five and six of the ALAT Training Manual/ALL • Facility Equipment & Caging Systems

Chapter Five

Facility Equipment

Cage Washers Use a combination of water and

cage cleaning chemistries to sanitize cages, racks and accessories Typical flow is dirty side to cage

washer to clean side

Cage Washers

Cage Washers

Programmable cycles consisting of prewash, wash, rinse and final 180ºF (____ºC) rinse

Cage Washers

Programmable cycles consisting of prewash, wash, rinse and final 180ºF (82.2ºC) rinse

Tunnel Washers Process soiled small equipment

and accessories, including cages, wire-bar lids, lids, bottles, sipper tubes

Rack Washers Designed primarily for larger

equipment, such as bulk carts, cage racks and large animal cage banks

Cabinet Washers

Similar to household dishwashers. The technician loads the equipment onto a wash rack, pushes the rack into the machine, closes the door and sets the wash conditions.

Cage Washer Safety

Red emergency stop buttons on all washers and autoclaves

Cage Washer Safety Door release mechanism within the

washing chamber

Cage Washer Safety Door closure latches to prevent

entry during the cycle, windows in the entry and exit doors and washer malfunction alarm systems

Pressure Washers

Spray water at very high pressure They are generally used in cage

wash applications and in facilities that house large animals in runs Animals should never be in a cage or run which is being sprayed Can remove paint from walls, injure user and injure animals

Decontamination Misters & Foggers Spray disinfectants and sterilants

as a fine mist. This equipment can be used to remove harmful microorganisms in rooms instead of manually washing and scrubbing the surfaces

Foamers May be hand-held devices or electric

machines and are commonly used to clean hallways, wash rooms, and rooms in facilities housing large animals The mixture of water and disinfectant is aerated into foam as it passes through a series of screens

Watering Systems

Automatic watering systems are often used to provide clean drinking water for laboratory animals. These systems save labor by eliminating some of the manipulations associated with cleaning, disinfecting and handling water bottles. They also help to eliminate the ergonomic injuries from constant handling of water bottles.

Automatic Watering System

Plastic or stainless steel pipes and valves that move water from the source to the animal areas

Automatic Watering System

Pressure reducing station

Automatic Watering System

Retractable recoil hoses

Automatic Watering System

Manifold system on the cage rack

Automatic Watering System

Connected to the manifold at each cage position are drinking valves

Automatic Watering System

It is important to remember that newly weaned mouse pups often cannot activate a water valve and should be placed in cages with a gel hydration pack or water bottle for at least a week after weaning.

Automatic Watering System

The filtering system removes particulate matter from the water supply before it reaches the animal cages.

Automatic Watering System

Automatic watering systems must be checked daily and maintained regularly. If they are not: Water lines can become clogged The drinking valves can become clogged

or Remain in the open position Microorganisms can accumulate in the

tubing

Automatic Watering System

Reducing Risks of Contamination To reduce the risk of

contamination, the animal’s drinking water is often treated with an acid, chlorine, reverse osmosis (RO), or ultraviolet (UV) radiation.

Automatic Watering System

Feeding Equipment

Change Stations or Laminar Flow Cabinets These units should not be

used with hazardous agents, anesthetic agents, or caustic chemicals. The cabinet protects the animals by blowing HEPA-filtered air through the back wall

Cage Dumping Stations

Fume Hoods

A fume hood is a workstation cabinet that protects the user from chemical fumes.

Biological Safety Cabinets

(BSCs) Are specially designed work cabinets that have a duct at the top through which air is exhausted. An animal facility that uses infectious agents must have BSCs to protect personnel from exposure to these harmful microorganisms.

HEPA

High Efficiency Particulate Air filter that removes a minimum of _____% of contaminants that are 0.3 micrometers or larger in size

HEPA

High Efficiency Particulate Air filter that removes a minimum of 99.97% of contaminants that are 0.3 micrometers or larger in size Annual Certification

Class I BSCs

Often used to enclose equipment that has the potential of generating aerosols or dust and for such activities as changing small animal cages.

Class II BSCs Draw air into the cabinet and filter

it; cabinet air is also filtered before it is recirculated or exhausted. Type A1, Type A2, Type B1, and Type B2

Class III BSCs (___________)

Class III BSCs (Glove Boxes)

Airtight cabinets designed to be used with high-risk biological agents.

Autoclaves Most autoclaves use high-

temperature steam under pressure to kill microorganisms in liquids or solid materials. Used to sterilize the equipment needed for Aseptic surgical procedures, animal housing,

feed, water and bedding.

They are also used to decontaminate biohazardous wastes

Autoclaves Compared to other sterilization

methods, autoclaving is fast, reliable and relatively inexpensive. Additionally, autoclaving avoids the use of toxic chemicals.

Autoclaves Steam and high pressure combine

to create superheated steam in excess of ___ºF (100ºC)

Autoclaves Steam and high pressure combine

to create superheated steam in excess of 212ºF (100ºC) Minimum times for a cycle are usually 15

minutes at ___ºC (250ºF) at 15 psi

Autoclaves Steam and high pressure combine

to create superheated steam in excess of 212ºF (100ºC) Minimum times for a cycle are usually 15

minutes at 121ºC (250ºF) at 15 psi Flash cycles of 5 minutes at 132.2ºC

(270ºF)

Superheated steam penetrates wrapped items Need to wear heat resistant gloves

Chemical Indicators

Autoclave tape Integrator strips Plastic indicator bags

Biological Indicators Spore strips, are the most

accepted means of making sure that the sterilization process took place. We use spore ampoules

Vacuums

HEPA filtered to prevent the spread of dust and allergens when in use Commonly used to clean hoods and similar

equipment

Tissue Digester

Similar to very large pressure cookers. These units are a safe, efficient, and cost-effective way to dispose of carcasses and tissues Remaining slurry or thick liquid can be

safely disposed of through the sewer system

Incinerators Large ovens that burn tissues,

trash, and other materials to ash. Incineration kills infectious organisms and so is suitable for the disposal of biohazardous waste Ashes removed from the incinerator are

disposed of as normal trash or taken directly to a landfill. The use of incinerators is highly regulated

in most states and localities.

Scales & Balances

Scales and balances come in various forms and sizes, from small table-top units to large walk-on units. Most scales provide digital

readings. Another type of scale, called a balance,

uses a weighing platform and a sliding beam to determine a weight.

Scales & Balances

Inspected and calibrated ________

Scales & Balances

Inspected and calibrated annually

Chapter Six

Caging Systems

Animal Housing

Primary enclosure refers to the cages in which the animal is enclosed for housing Caging and housing = primary enclosure

Cages must be escape proof and well ventilated Free of cracks and crevices with smooth

surfaces and no rust

Animal Housing

Cages should allow visual inspection of animals and permit safe handling Specialized caging such as

transport boxes and transfer cages are used to move animals

Types of Cages

Most popular caging system used for rodents consists of ventilated racks that hold microisolation cages. Rodent microisolation cages may also be placed on racks of metal shelves, either stationary or on wheels

Environmental Enrichment Cages sometimes include objects

and materials for enriching the environment of laboratory animals. Environmental enrichment can: reduce boredom through mental

stimulation, provide a sense of security with hiding

places, offer an opportunity for exercise, or permit social interaction among cage

mates

Environmental Enrichment

Nesting material Toys Perches Swings Resting boards Foraging devices

containing food treats

The Animal Welfare Act and Regulations mandate that dogs be given the opportunity to exercise and that nonhuman primates be provided a psychological enrichment program

Plastic Caging Materials

Polysulfone most common plastic used for rodent

caging and fish tanks

Polycarbonate Impact- and temperature-resistant plastic

used to make many rodent cages and small aquatic tanks

Plastic Caging Materials

Polystyrene non-durable plastic generally used for

disposable, single-use caging applications

Polyphenylsulfone used frequently to make caging that is

used for work with high-risk infectious agents. This type of plastic is more resistant than polysulfone to extreme autoclave temperatures

Plastic Caging Materials

Polyethylene (PET) Used for single-use, disposable caging

Polypropylene Sometimes used for suspended rodent

cages, aquatic tanks and rabbit cages.

Metal Caging Material Stainless steel Most commonly used metal in laboratory

animal caging. It is more expensive than aluminum but is preferred because it does not visibly rust or corrode.

Galvanized metal was used in older generations of caging and may still be found in some facilities. This type of caging is not generally used today because of problems with rust and corrosion

Caging Systems The size of a primary

enclosure depends upon many factors, including experimental requirements and animal-related characteristics such as: body weight, height or length, exercise requirements

and enrichment needs

The Guide and the standards of the Animal Welfare Regulations detail minimum cage sizes and characteristics. An animal must have

at least enough space to stand up, turn around, lie down and make other normal postural adjustments.

Shoebox Caging Rectangular box that is used for

smaller species such as rodents. A wire lid fits or hooks tightly onto

the cage to prevent the animals from escaping

Microisolation Cages Creates a barrier or containment

system at the cage level, preventing an exchange of microorganisms between the cage and the environment.

Individually Ventilated Cages (IVCs)

Each cage becomes a controlled environment for the flow rates and filtration of incoming and outgoing air If the ventilation fails on a sealed

cage, carbon dioxide levels can rise inside the cages

Biocontainment Cages Provides complete separation of

animals from the external environment Operates under special conditions

that prevent the escape of harmful pathogens or dangerous substances to the outside environment Cage clamps to prevent accidental

opening of a cage

Disposable Caging

Can be used when cage washing facilities are limited May also be used for studies

involving radioactivity or biohazards

Suspended Cage Systems

A rabbit cage typically has a hinged front panel that opens like a door

Dirty cages are typically

left on the rack and the cage rack is wheeled to cage wash

Suspended Cage Systems

The suspended cages slide forward on the runners, opening much like a drawer. They close simply by sliding them back under the shelf

Suspended Cage Flooring

Floors may have openings (wire mesh or perforations) or may have solid bottoms. The Guide does not recommend

wire-bottom caging for rodents because of the potential for foot injuries

Large Animal Caging

Primates, dogs, cats, swine and other large animals are housed in caging systems designed for that particular species based on body size space requirements configuration required number of animals housed together

Modular Cages Stacked caging is similar to

suspended caging, except the cages are fixed in the rack instead of being suspended on runners

Modular Cages

These kinds of cages are used for: rabbits (in addition to suspended cages) cats dogs ferrets nonhuman primates

Cat housing must provide a raised resting platform and a clean litter pan with fresh litter daily

Group Caging Multiple animals of the same

species When animals are group caged: feed and water are often offered in more

than one location in order to avoid feed hoarding by dominant animals

Cats, rabbits, nonhuman primates, and sheep are examples of animals frequently housed in groups

Runs, Pens, & Kennels

This type of caging is commonly used to house dogs, sheep, pigs, and goats.

Floor Options for Runs, Pens & Kennels

In pens with a raised floor, the floor is a mesh or slotted surface that may be vinyl-coated steel or fiberglass. In many facilities, the room flooring is a

waterproof surface that slopes to aid the drainage of water and urine away toward a gutter at the back of the room. Such rooms generally have a flush system for the disposal of wastes.

Runs, Pens, & Kennels Front panel of this type of caging

has a built-in bracket for removable stainless steel feeders or troughs. Water is commonly provided through

automatic systems of watering manifolds and drinking valves. Alternatively, water may be provided in

stainless steel bowls fixed in cage brackets.

Runs, Pens, & Kennels

Nonhuman Primate Caging

Indoors, NHPs may be housed in cages on racks in group caging in cages attached to the wall

Nonhuman Primate Caging

Some cages, called squeeze cages, have a movable back wall that slides forward Some cage systems are modular and have sliding panel dividers between adjacent cages

Activity Cage or Area

NHPs can be housed outdoors in a variety of housing systems that are typically custom-built

Aquatic Caging

Aquatic caging systems must have a water source and a drain Designed to effectively manage

large volumes of water Usually consists of units that have

several shelves supporting tanks made of transparent material

Cubicles

Designed to function as mini animal rooms within a larger room

Agricultural Housing

Agricultural animals may be kept in research buildings or in barns. Swine, sheep, and goats may be housed indoors in pens or kennels at floor-level or on elevated platforms A disadvantage of corrals and

pastures is the difficulty of immobilizing or restraining a single animal.

Metabolism Cages Spilled feed and water can be

collected to allow for the accurate measurement of feed and water intake Urine and feces are channeled to

separate collection tubes

Transport, Transfer, & Shipping Cages

Amount of time the animal will be in the transport cage determines the need for feed and water Follow the regulations of the AWA regarding species-specific space requirements and the provision of feed and water during transit

Space Recommendations Space recommendations for most

common laboratory animals are provided in the Guide, which states that at a minimum: an animal must have enough space to turn

around and to express normal postural adjustments must have ready access to feed and water must have enough clean bedding or

unobstructed area to move and rest in

Space Recommendations

Whenever possible, social animals should be housed in pairs or groups, rather than individually Cages should balance the needs of

the animal with the ability to provide for sanitation

The End