Animal Housing Flashcards
(27 cards)
What is the effect of low temperature on animals?
- Cold stress, only 25% metabolisable energy to tissue growth and 75% lost as heat
- Younger animals prone to hypothermia
What is the effect of high temperature on animals?
Initially restless, then lethargic, brief frenzied activity, convulsions, death.
Clinical signs: dyspnoea, tachycardia, weak pulse, cyanosis and pyrexia
Describe thermohomeostasis.
Heat loss via convection, evaporation, radiation, respiration and condition. Wild animals adjust loss by panting, swallowing, social distinction or huddling and sheltering. Artificial conditions may not allow this and cause heat/cold stress.
Define thermal conductivity and state its equation.
Thermal conductivity, k - the property of material quantifying the rate of energy flow across it.
q = -k x (T2-T1)/L
where q = insulative capacity
Which materials are used to insulate buildings for animal housing and why?
Rockwool - settles with age, reducing insulation. Susceptible to vermin, requires water vapour barrier.
Expanded polystyrene - vulnerable to vermin, flammable due to highly toxic fumes, requires vapour barrier.
Polystyrene foam - spray on to any shape, water resistant, rodent proof and non-toxic when dry.
Reflective materials - prevent heat loss by radiation.
Closed environment with controlled ventilation - prevent heat loss by convection.
What are the functions of ventilation?
Temperature regulation by temperature lift (= required temp - outside temp)
Humidity regulation
Air hygiene - provide fresh air and remove aerial pollutants
Which gases can contribute to contamination of livestock building?
Ammonia - hyperplasia of epithelial lining, micro-abscess formation, hyper-secretion by goblet cells increases depth of mucus layer, impaired ciliary function.
Hydrogen sulphide - throat and nose irritant, respiratory paralysis, death at high concentrations.
CO2 - headaches, nausea, anaesthetic and fatal at high concentrations.
CO - fatal as it affects binding to haemoglobin.
Methane - not direct pollutant but greenhouse gases.
Dust - from bedding, feed, integument, dry faeces and spores
Describe lighting in different animals housing.
Cattle prefer brighter areas. Will have lesions and swelling at lower intensities.
Pigs cope better with dim lighting.
Different intensities required for different eyesights to allow to performance of normal behaviours.
What are the species variations of photoperiod?
Photoperiod affects melanin production, which modulates hypothalamus-pituitary gonadal axis.
Increased = stimulates behaviour in horses, cows, pigs and birds Decreased = stimulates behaviour in sheep and deer
What are the advantages of cement flooring?
Durable Inexpensive Resistant Good load bearing characteristics Can be moulded Abrasive quality varied Impermeable to water Strong under compression.
What are the disadvantages of cement flooring?
Hard Poor physical and thermal comfort Slippery when worn and slurry covered Can be abrasive Difficult to completely clean Edges easily broken Corrosive when new Weaker under tension
What are the advantages of slatted concrete flooring?
Separates bulk of excrement from stock Reduces degree of heat loss Durable Relatively cheap Relatively non-slip
What are the disadvantages of slatted concrete flooring?
Hole/slot size essential to avoid injury Difficult to clean Incompatible with bedding Unsuitable for small stock Bursitis Hock and foot lesions Abrasion Foot injuries
What are the physical and behavioural attributes of bedding?
Physical:
- Physical and thermal comfort, particularly in young stock
- Absorbent
- Hygienic, keeps animals clean if bedding is kept clean
Behavioural:
- Nest building
- Foraging behaviours
- Play
- Dust bathing
What are the advantages and disadvantages of straw bedding?
Softer and more absorbent than wheat, can be eaten , 300% absorbency.
Bulky and expensive to transport, dusty and contains fungal spores if poorly made.
What are advantages and disadvantages of wood shaving bedding?
200-300% absorbency but more expensive than straw.
What are the advantages and disadvantages of sand bedding?
Drains waste, no fungal spores so doesn’t encourage microbial growth, non-abrasive, cool in summer and long lasting.
Can be difficult to dispose of and can cause wear to slurry handling equipment.
What are the advantages and disadvantages of hemp fibre bedding?
500% absorbency and no fungal spores, but very expensive.
What are the advantages and disadvantages of rubber bedding?
Physical and thermal comfort and non-slip.
No absorbency so needs additional bedding.
What is the least expensive housing to build?
Climatic
Which species has a broad thermo-neutral zone?
Cows
What is the occupational exposure limit of hydrogen sulphide for humans?
10 ppm in 8 hours
What is the maximum air speed in animal housing to prevent chill?
30 cm/s
What should the light intensity in a dairy herd be?
200 lux
