VL01_Animal Husbandry

Animal husbandry in experimental animal science should:

• optimise the health and well-being of the animals •

• support the conduct of experiments

In addition, animal husbandry must

• comply with the relevant regulations

• avoid or reduce occupational hazards

• be easy to operate.

Any factor or condition that can change is a variable.

An experimental variable causes a reaction

• it is the intervention that distinguishes the experimental group from the control group.

A non-experimental variable:

• causes unwanted results or differences

• is usually the result of behavioural or genetic factors

• can destroy the integrity of data

• should at least be recorded and reported

• should be reduced/avoided through careful planning and adherence to the experimental setup

There are three distinct areas:

1. "Megaenvironment" – the animal house/ Vivarium

2. "Macroenvironment" – the animal room

3. "Microenvironment" – the immediate surroundings, e.g. the cage

• Several animal species with different hygiene requirements under one roof

• Each animal species should be housed in its own area

• New arrivals should be kept in quarantine

• Animals used in experiments should be kept separate from animals used for breeding and husbandry, as well as away from the experimental rooms

The “macroenvironment” = the animal room

• The main criteria for animal housing are ventilation, lighting, and noise and vibration control

• Adequate ventilation provides the animals with fresh air, transfers heat to or from the room, dilutes and removes CO2 , ammonia and contaminants, etc.

• Most laboratory animals require an air temperature between 18 24°C and relative humidity between 45-65%.

• The air in the animal room should be exchanged between 10 and 15 times per hour

Light

• light intensity, duration and wavelength should be appropriate for the respective species

  • Albino animals in particular are susceptible to retinal degeneration at high light intensities

• Light intensity Cage <60 lux, Light intensity in the living area < 200 lux

• Light intensity for specific activities < 400 lux

• The length of daylight influences biological rhythms

  • Lightphase between 10 and 12 hours

    —> Main activity times for mice and rats – dusk

Noise

• An unavoidable part of any animal facility (cage preparation, fan and ventilation units, transport trolleys, etc.) •

• Structural measures for spatial separation

• Loud noises are stressors for many animals (audiogenic epilepsy)

Vibration

• Disturbs well-being, stressor, reduced litter sizes and breeding rates

The "microenvironment" = the cage or immediate surroundings Objective:

• keep the animals comfortable and safe

• be reasonably priced

• meet the needs of the experiment, and

• must comply with legal requirements

• Important for care taking staff: lightweight, easy to clean, allergen free, etc.

The requirements for the cage depend on the animals to be kept and the requirements of the experiment

The necessary size of a cage depends on many factors, e.g.:

• Body weight

• Height, climbing requirements

• Breeding or husbandry

• Experimental requirements

• Activity of the animals

• Enrichment

Open cageing

• Proven principle

• Cost-effective

• Barrier at room level

• Relatively flexible

Animal housing cabinets

• Designed for small animal husbandry or special applications

• Open cages

FilterTopCage (FTC):

• Filter hood protects cage contents from contamination

• Reduces allergens

• Poor ventilation

• Frequent cage replacement necessary

IVC (individually ventilated cages):

• Maintains protective functions of filter cages

• Very good ventilation

• Both, positive and negative pressure possible in the system

• Weekly cage change sufficient

Insulators

• Highest level of protection in both positive or negative pressure

• Open cages in the insulator

• Very high labour intensity

TierSchVersV 2013, § 1 Anforderungen an die Haltung

Der Leiter der Einrichtung ... hat sicherzustellen, dass

1. die Haltung der Tiere, auch während ihrer Verwendung in Tierversuchen, den sich aus Anhang III der Richtlinie 2010/63/EU des Europäischen Parlaments und des Rates vom 22. September 2010 zum Schutz der für wissenschaftliche Zwecke verwendeten Tiere (ABl. L 276 vom 20.10.2010, S. 33) in der jeweils geltenden Fassung ergebenden Anforderungen entspricht

2. mindestens einmal täglich das Befinden der Tiere durch Inaugenscheinnahme direkte und die Haltungsbedingungen sowie die Funktionsfähigkeit der der Haltung dienenden Anlagen durch geeignete Maßnahmen überprüft werden

Article 33 – Care and accommodation

1. All animals shall be provided with accommodation, environment, food, water and care appropriate to their health and well-being

2. all factors that restrict an animal's ability to satisfy its physiological and ethological needs shall be kept to a minimum;

3. the environmental conditions for breeding, keeping or using the animals shall be monitored daily;

Mouse Type II long cage (540 cm²):

• Occupancy 5 adult animals

• Mating max. 2 female X 1 male

Rat Type III R:

• Only animals up to max. 600 g, from 400 g only individual animals

Type 2000, double decker (1800 cm²)

• 5 rats weighing 300-400 g

• from 600 g only 3 rats

Special conditions for rats

• Tolerate low temperatures well, but hardly tolerate higher temperatures (standard room temperature 18-24°C)

• Beware of draughts!

• Humidity between 40-70% relative humidity, if too low- "ringtail"

• High ammonia levels in the air irritate the respiratory tract and predispose rats to infections

• Rats need a dark area where they can retreat

Housing conditions

• Young animals in particular have a pronounced need for exercise

• Floors should be non-slip

• Privacy screen and hiding places to reduce aggressive behaviour

• Roughage and gnawing opportunities

• The size and edges of holes in perforated floors must be such that they prevent pododermatitis (especially in heavy rabbits)

• Rabbits use elevated areas to observe their surroundings

• If elevated areas cannot be provided, the floor space should be increased by 40-60% depending on weight

• Room temperature– cool! (15 – max 21°C)

• Sudden noise (e.g. when entering the room) should be avoided

Watering devices

• Central water supply

  • Mainly in large facilities (reduced workload)

  • Centralised treatment and distribution in the building

  • Circulation and flow-through systems

• Drinking bottles —> internal or external

• Water bags —> internal or external

• Water in gel form

Water treatment:

• Autoclaving

• Ultrafiltration

• Acidification

• Reverse osmosis