Farming Flashcards
what type of fermentation is used in different types of herbivores
foregut - ruminant
hind-gut - equids / lagomorph
non-fermentation - rodents
what factors make up gross energy
faecal energy and digestible energy
what factors make up digestible energy
urine
metabolisable
gaseous
what factors make up metabolisable energy
net energy
heat increment
what makes up net energy
for production (energy retention for work / milk / meat) for maintenance
what factors contribute to the total heat production of an animal
the heat increment
maintenance
what percentage dehydration leads to serious consequence an death
10% = serious 15-20% = death
what are the sources of involuntary water loss
respiration
perspiration
what are the 2 sources of water
ingestion (food/liquid)
metabolism of water through oxidation process
what is ad libitum
open access to water at all times
what are the 2 main classifications of carbohydrates
sugars (monosaccharides / ogliosaccharides) non sugars (polysaccharides / complex CHO)
what are some examples of monosaccharides
glucose
fructose
mannose
what 2 monosaccharides are required in milk production
glucose
galactose
what are some examples of disaccharides
sucrose
lactose
what are some examples of polysaccharides
cellulose
starch
glycogen
what are the rate limiting amino acids in milk production
lysine
methionine
what are essential amino acids
ones that cannot be produced by the animals body so must be consumed
how do you calculate the crude protein of a feed
6.25 x total nitrogen content
what percentage nitrogen does crude protein contain
16%
what is the protein standard for horses
digestible crude protein
what is the protein standard for pigs / poultry
total ideal protein supply
what is the protein standard for ruminants
metabolisable protein supple
what is the metabolisable protein system in a ruminant
separated into rumen degradable protein (slow/quick digestion) / un-degradable protein (digested in the small intestine)
what type of protein enters and leaves the rumen in digestion of rumen degradable protein
crude protein enters and microbial crude protein leaves and is then digested by the animal
what is produced from non glycerol based lipids
prostaglandins
steroids
what structural products are formed from glycerol based lipids
glycolipids
phospholipids
what li[ids are required in an animals diet
polyunsaturated fatty acids
omega 6
linoleic / leinoleic acid
what is the function of omega 6
prostaglandin production
what is the function of polyunsaturated fatty acids
maintaining membrane fluidity
why can ruminants not digest high levels of fat
it causes damage to the rumen microflora
name two antioxidants
vitamin E
selenium
name some fat soluble vitamins
retinol (vitamin A)
vitamin E
where is vitamin K produced
microbes in the hindgut
name some water soluble vitamins
B1 thiamine
B2 riboflavin
vitamin C
what is forage
the aerial constituent of a plant fed to livestock (leaves / grass / straw)
when is the maximum production of forage
late spring/summer
why is harvest seasonal surplus important
for feeding animals in winter
what is conserve
drying / pickling forage to store the product for longer
what are the types of pasture
rough grazing (heather etc present) permanent pasture (ryegrass) rotational grass (short term ley crop)
what plants would be present in a sown pasture
grasses e.g. ryegrass
legumes e.g. white clover
what is the importance of legumes in a pasture
fixing atmospheric nitrogen for the animals consumption / for other plants to grow
what is grass production dependant on
pH
climate
irrigation / drainage
what affect does age have on the composition of grass
decrease in protein / fat increase in cellulose
what is lignin
basically wood - undigestible
what is the metabolisable energy of grass
7-13 MJ/kg of dry matter
what is the result of animals eating older grass (lower quality)
more fibrous
less energy dense
less palatable
lower production
what are the features of a forage maize crop
large amounts of feed can be produced per hectare high starch (therefore high digestible matter) low protein but not frost tolerant
what are the features of a whole crop cereal crop
wheat / barley / oats
made into silage
low protein and moderate energy
what are the features of root crops
beets / swedes / kale
good for winter feeding particularly up in the north of UK
how is forage conserved
drying
ensiling
describe the process of silage
fermenting the forage in absence of oxygen - should be left to dry for a day before
what changes occur during silage fermentation
water soluble carbohydrates converted to lactic acid lowering the pH killing the bacteria creating a stable long storage product
what are the nutritional targets for grass silage
30% dry matter
with a stable pH of around 4.6 and low ammonia nitrogen
what is aerobic spoilage of silage
yeast / mould growth making product unpalatable and toxic
what are the downsides of hay production
needs 4-5 days of dry weather / artificially dry (expensive)
what can cause nutritional loss to hay
enzymes / mold
mechanical damage (leaves broken)
leaching / oxidation
what are the advantages of hay vs silage
more palatable
easier to transport
less contamination risk e.g. botulism / clostridia
what his haylage
in between hay and silage - higher water than hay but lower content
what is straw and what is it used for
stems of wheat / oat
bedding / forage (low nutrition high fibre)
what are concentrates
energy dense high protein feed
why is roughage needed in a diet with concentrates
to avoid acidosis
what are the types of concentrate
straights - one grain type / food industry bi product
mixes - variety e.g. muesli
why are some concentrates processed
to increase bioavailability
what are some conditions associated with forage
mineral imbalance
metabolic disorders
poisonous plant consumption
nitrate poisoning
describe climatic animal housing
houses with no insulation and natural ventilation with temperatures close to ambient
what are the benefits to climatic animal housing
least expensive
most versatile
describe controlled environment animal housing
- large
- well insulated
- thermostatically controlled mechanical ventilation
- heavily stocked
what are the positives and negatives of controlled environment animal housing
highly automated (less staff needed) expensive
describe micro environment animal housing
small modules
naturally ventilated
insulated
temp. regulated by heat from animal stocks
what is the thermo-neutral zone
the temperature range where external temperature does not effect metabolic rate
what is the upper critical temperature
the temperature at which if exceeded heat stress occurs e.g. decreasing food intake / holding wings away from body
what is the lower critical temperature
the temperature at which if dropped below cold stress occurs e.g huddling together
which animals have a narrow thermoneutral zone
pigs
poultry
which animals have a wide thermoneutral zone
ruminants
how do pigs / poultry maintain homeothermy and where should they be housed because of this
adjusting feed intake (metabolisable energy)
housed in controlled environments
how do ruminants maintain homeothermy and where should they be housed because of this
through insulate qualities of coat / behaviour (no change in food intake)
house in naturally ventilated environments
what are the downsides of housing / farming intensification
increase in complexity = increase cost of materials / energy / labour / sustainability concerns
what factors must increase to offset cost increase of intensification
efficiency
number of animals
production
automation
what are the potential impacts of poor housing on animals
injury
disease spread
how does poor housing design / management lead to disease spread
poor ventilation = resp. diseases
poor cleaning = infection
what are the potential behavioural impacts of poor housing on animals
horses - stereotypy
pigs - tailbiting
what factors should be considered when designing effective housing
temp / thermodynamics social grouping lighting cleanliness air quality / ventilation biosecurity insulation flooring / bedding
what are the consequences of low air temperature on energy
higher proportion of ME is used to replace heat lost so production efficiency is decreased
what percentage of ME is used in tissue growth
25%
what are the stages of heat stress behaviour
restlessness lethargic brief frenzied activity convulsions death
what are the clinical signs of heat stress
dyspnoea (cant breathe) tachycardia cyanosis weak pulse pyrexia (fever)
what you expect from a post mortem of an animal which died of heat stress
blood stained froth in nostrils
lung oedema
how do homeothermic animals maintain temperature homeostasis
produce heat - huddling / sheltering / metabolising energy
lose heat - respiration / evaporation / panting / wallowing
how do buildings loose heat and how is this controlled
convection -air in contact with surfaces
conduction - through floor / roof
radiation - radiant heat from building surfaces
controlled via insulation and ventialtion
how is the insulate capacity of a material defined (k)
thermal conductivity
thermal transmittance
what is the thermal transmittance (U)
rate of heat transferred through a material per meter per degree of temperature difference
how do you calculate the insulate capacity
inverse of thermal transmittance / thermal conductivity
how are buildings insulated
lining with materials with low thermal conductivity - rockwool / expanded polystyrene / polyurethane foam
what are the downsides of using rockwool insulation
settles with age
susceptible to vermin
needs waterproof barrier
what are the downsides of using expanded polystyrene insulation
flammable with toxic fumes
needs waterproof barrier
susceptible to vermin
what are the benefits of using polyurethane foam insulation
any shape
water resistant
non toxic
rodent proof
how do you prevent heat loss through radiation in a building
using reflective materials inside
how would you prevent heat loss through conduction in a building
making it closed environment controlling it through ventilation
why is effective ventilation important
humidity regulation
temp regualtion
air hygiene - fresh air / aerial pollutant removal
describe natural / passive ventilation
the stack effect
gap in the top of building that allows rising warm air to be released
what is the downside to using passive ventilation
under ventilates in summer and vice versa in winter so can only be used in mild climates
what are the 2 types of mechanical ventilation
negative pressure / postive pressure
describe negative pressure ventilation
fans on one side expel air creating a partial vacuum which draws fresh outside air into the house through inlets
what are the consequences of mis-sized air inlets in a negative pressure ventilation system
too big = draft
too small = does not fully ventilate the building
what are the advantages of negative pressure ventilation
cold air mixes with cold air before reaching animals so they do not have temp shock
describe positive pressure ventilation
fans push air into building forcing hot animal air out of the building distributing heat / mixes air before reaching the animals
why is ventilation an important factor in animal temperature control
removes warm air
allows animals to effectively use evaporation (needs air movement)
what speed should wind not exceed to reduce the effect of wind chill
30cm/second
what is the minimum ventilation rate
2 m cubed per tonne of food consumed per day (5 whole house air changes per hour)
how do you calculate the temperature lift
required temperature - outside temperature
what happens when the temperature lift figure is large
heat produced by animals is not sufficient to keep themselves warm = cold stress
what is the relative humidity
% saturation of the air with water vapour
how do you calculate relative humidity
(mass of water vapour x 100) / mass of water vapour when saturated
what can be the consequence of high temperatures and high humidity
evaporative heat loss impaired so heat stress can be exacerbated
what can be the consequence of low temperatures and high humidity
increased thermal conductivity of air so increased chill
what are the negative effects of high humidity
dermatitis corrosion formation of ammonium hydroxide reduce insulation effectiveness increases survival rate of microorganisms forming surface water
what are some potential air pollutants
noxious gas
dust
microorganisms
allergens
what can occur if pollutants are not removed by ventilation
sedimentation
inhalation
what are some common gaseous pollutants and their consequences
ammonia / CO /CO2 / methane (ruminants)
compromises respiratory tract defence systems
how is ammonia generated
microbial fermentation of excrement and urine
what are the ammonia occupational exposure limits
livestock max 20ppm
humans 25 ppm for 8 hours
what is the effect of ammonia when absorbed into body surfaces
hyperplasia of epithelial lining
micro-abscesses
hyper-secretion by goblet cells (increased mucus layer)
impaired ciliary function
what produces hydrogen sulphide in a farm setting
anaerobic bacteria in slurry. tanks - olfactory perception reduces with exposure
what can be the result of exposure to high levels of hydrogen sulphide
respiratory paralysis
nose irritation
death
what can be the result of exposure to high levels of CO2
headaches
nausea
anaesthesia (accumulates in slurry pits as heavier than air)
how is methane formed in a farm setting
microbial methanogensis from anaerobic respiration in the ruminant gut
what can be some sources of dust
bedding
feed
dry faeces
microbial flora/spores
what activities cause increased aerial dust burden
mucking out
where are large dust particles deposited in the body
upper resp. tract due to impaction (resp. walls due to anatomical branching and the slow moving nature of the particles) - inspirable particles
where are small dust particles deposited within the body
lower resp tract through sedimentation - respirable particles
how do dust / aerial microbes effect particle retention time in the lungs
allows particles to be retained in the lungs as the microbial endotoxins compromise mucociliary clearance / alveolar macrophage activity
what is the minimum lighting in a pig house
40 lux
which animals prefer high /low lighting
cow = bright so milking areas should be well lit to encourage entrance pig = dim - may avoid light areas
what can be the result of high light intensity
aversive to eyes
what can be the result of low light intensity
animals are unable to perform normal behaviour e.g. finding food / social interaction
what kind of light should be provided for prey species
darker sheltered areas to make them feel safe or for feeding
how does day length affect the reproductive system (photoperiodicity)
affects the melatonin production with modulates the hypothalamus-pituitary-gonadal axis
which animals reproductive behaviour is simulated by an increase in day length
horses
cows
pigs
birds
which animals reproductive behaviour is simulated by an decrease in day length
sheep
deer
how does light intensity effect photoperiodicity
need 200+ Lux for mammals reproductive behaviour but only 10+ Lux for birds
why would manipulating the photoperiod be useful
improving milk production volumes / allowing young to be born on a timeline convenient to the farmer
what is the dark period and why is it important
sleep time - inhibits melatonin production / disruption of resting behaviour causing stress
what are the 2 types of light receptors
rods - most sensitive and to yellow
cones - less sensitive with specific pigments so they can only see a restricted spectrum of light
what part of the light spectrum are cows / pigs most sensitive to
blue as they are dichromatic - blue and green
what are the implications of differing light frequency recognition for animals vs humans
animals may not be able to distinguish items - exacerbated under artificial light as they are designed for human eyes
how would non-UV emitting artificial lighting negatively affect livestock
birds dependant on UV. for recognition / mate selection / sexual behaviour = increased stress (corticosterone)
impaired vitamin D / melanin synthesis (mainly affects birds and reptiles)
what are the effects of exposure to flickering light
headaches
neurological disorder
visual effects
what is the flicker fusion threshold
frequency at which an intermittent (flickering) light appears constant - animals may be higher so flicker may be visible
what features should animal housing flooring have
non-slip comfortable hygienic free draining abrasive (to cause footwear) but not injuring
why is there a need for cubicles for ambulatory (grazing) species when they are not in a straw yard
they defaecate then walk on with no specific toilet area so this prevents them from doing this in their sleeping areas
what is the most common type of agricultural flooring
solid / slatted concrete
what are the advantages of concrete flooring
variable abrasiveness can be moulded durable inexpensive water impermeable strong under compression
what are the disadvantages of concrete flooring
poor physical comfort
slippery when worn
difficult to sterilise
can be very abrasive
what are the potential injuries associated with concrete flooring
bruising to sole of the foot
hygroma / bursitis (fluid buildup) from lying on hard floor
traumatic / chronic abrasions
what are the benefits of slatted concrete floors
separates excrement bulk from stock / reduces heat loss via conduction / provide adequate footwear
what are the disadvantages of using slatted concrete floors
slot size is critical to avoiding injury
no slot size suits all stocks
cannot clean
incompatible with bedding
higher stocking density required / poor physical comfort
what other kind of slats are used in animal housing and for which animals
metal - cows
weld mesh - pigs /poultry
plastic - pigs (but doesnt wear down feet)
wooden - poultry (but hard clean)
what physical features should you look for in an effective bedding
physical and thermal comfort
absorbent
hygienic
manipulative (for nesting / foraging / play)
what are the main types of bedding
straw
rubber
sand
wood shavings
describe straw bedding and its advantages / disadvantages
barley (will eat) / wheat
cheap if locally produced
but dusty if poorly made
high absorbency
how much straw is required for different animals per year
horse 3 tons
dairy cow 4 tons
beef cow 2tones
describe use of wood shavings as bedding
for horses / poultry
more expensive
high absorbency
describe the use of sand as a bedding material
dairy cow cubicles and laid over a porous substrate so that waste drains through
what are some disadvantages of sand bedding
have to maintain depth
difficult to dispose of
causes wear to slurry handling equipment
what are some advantage of sand bedding
long lasting
cool in summer
non-abrasive
inert (no fungal spores)
describe the use of hemp fibre as bedding
horses and small animals
very very absorbent
very expensive
no fungal spores
describe the use of rubber bedding material
good physical / thermal comfort
non slip
but no absorbency so other bedding has to be used
