Intro to Care & Housing

Question 1

Examine different animal housing systems and make a judgement on the sustainability of the shelters for the animals involved, and the person(s) working with the animal.

Answer 1

Disease considerations-
- Align the sheds to minimise spread of disease by windborne dust
- Sheds 500m apart (not appropriate/functional for a normal farm - usually more like 5m apart)
- Minimise shed damage from prevailing winds
- Avoid entry of run-off water from sloping ground
- Avoid conurbations (schools/houses), because of odour
- Choose a site with good road access
- Consider effluent management before selecting the site

Ventilation systems - terms that are used:
- Natural ventilation - air escapes from the building by its own means, or removal may be wind-assisted
- Positive pressure ventilation - forcing air into a building usually with a fan (air can be filtered to prevent infectious air entering - aids in prevention around vulnerable animals)
- Negative pressure ventilation - extracting air from a building usually with fan (can be used in laboratories using infectious substances - air can be filtered to prevent pathogen escaping)
-Ducted ventilation - duct through which air is delivered within a building. Duct assists even distribution, and the air may be heated or filtered

Question 1

Describe any problems associated with houses that are not designed to the maximum benefit of the animals.

Answer 1

Floors and bedding:
Wet floors and wet bedding encourage-
- Slips and falls
- Flies
- Foot disorders
- Ammonia release (can also cause irritation)
- Air humidity
- Dirt adhesion to animals (not necessarily a welfare issue but is a sign that their environment is unhygienic)

Space requirements:
Overcrowding increases the risk of-
- Faecal soiling
- Foot disorders
- Poor air quality and respiratory disease
- Overheating during hot weather
-Competition for lying area, feeder space and drinker access, and hence aggression

Question 2

Discuss how the needs of animals are met in controlled environment housing.

Answer 2

Ventilation is used to control:
- Temperature
- Humidity (in some situations)
- Transfer of air-borne pathogens (but stocking density usually has a greater effect)
- Air quality-
—Ammonia
—Dust
—Hydrogen sulphide & carbon dioxide

Ventilation:
- Site the sheds so that dust is not blown from one shed to another
- For sheds with low roofs, fan assisted ventilation gives more reliable temperature control than natural ventilation
- Different shed ventilation systems produce different heat gradients within the shed
- Shed temperature can be regulated automatically through thermostatically controlled fan speed or inlet/outlet aperture size
- Pattern of airflow from a wall inlet can vary substantially between summer and winter
- Reversed ventilation gives a more even flow of fresh air through the shed, compared to conventional direction
- Positive pressure filtered air has the lowest risk of airborne pathogen entry into the shed

Question 3

Identify common health and production problems associated with sub-optimal housing.

Answer 3

• Farrowing crate restricts the movement of the mother to prevent crushing of the piglets
• Blue on an animal - usually being treated for a lesion
• High animal welfare issues for the mother in farrowing crates

Question 4

Discuss how animal housing can be designed to respond to different needs or requirements.

Answer 4

Design & construction:
- Floors
- Bedding
- Ventilation
- Housing & health

• Straw - leftovers from grain harvesting (like barley wheat stems) makes good bedding
• Hay - dried grass chippings
• Saw dust is typically used for young animals but can cause respiratory issues

Avoiding cold floors-
- Under-floor heating - used in some piggeries
- Under-floor insulation - loose brick rubble, drain tiles or polythene coated polystyrene slabs laid before the concrete
- Adequate depth of bedding - most bedding materials absorb moisture at compacted lower depths and have an aerated upper layer which provides insulation at surface

Slatted floors-
- Size of the slat and width of the gap must be suited to the size of the animals’ feet: to prevent trapped claws and claw separation
- Fully slatted floors should not be used for breeding animals - animals can get their hooves stuck (piglet can get their hoof stuck and mother sits on top, crushing them)
- Slat edges should be rounded: not sharp or chipped

Bedding materials:
- Straw - compressed straw nearest the floor takes up and holds moisture. Upper uncompressed layer moisture provides insulation and warmth. Straw stems need to be broken to take up moisture - big bale straw has more split stems and better water absorption. Barley straw is best for bedding livestock; wheat straw tends to be dusty.
- Sawdust - used for poultry, horses and cow cubicles. With poultry, sawdust is prone to capping if it becomes wet or the faeces contain fat. Capping can trap moisture and high concentrations of ammonia, increasing the risk of hock burn. Sawdust can lead to respiratory problems in horses, but can be reduced by placing straw over the sawdust.
- Wood shavings - less absorbent than sawdust. Can be screened to remove dust. Shavings from timber treated with preservatives can cause flavour taint in chicken breast meat.