Week 8 Flashcards
What factors control food intake?
Physical
- Stomach/rumen/ crop size etc
Chemical
- Glucose, CCK (cholecystokinin) in non ruminants
- VFAs In ruminants
Nervous/hormonal:
- Leptin & ghrelin?
Physiological:
- Energy density
Palatability
Deficiencies
Illness
Heat (hot eat less),
Obesity
Availability
Why do we need to predict/estimate food intake
Diet formulation
Feed availability
Feed budgeting
Reducing feed wastage
Determining stocking densities
Conservation management –how many fields can lay up
How can you optimise voluntary food intake
Clean troughs (so they can get to clean feed), enough trough space
Provide food at all times
Adequate clean potable water (inc feed moisture)
Good quality feed
No moulds/spoilage (optimum mins/vits)
Mixed forages – intakes better of mixes than single type
Short chop length – decreased transit time (decreased digestibility)
Increase palatability
What factors affect digestibility
Food composition
Diet/Ration composition
Preparation
- Rolling, crushing, grinding, alkali (NaOH, Urea/ammonia), heating, micronisation
Enzyme supplementation
Animal factors
- Individual variation
- Species variation
* Forages have higher digestibility for Ruminants than non ruminants (due to bacteria)
* Sheep tend to digest grain better than cattle
* Cattle tend to digest low quality forage better than sheep
Level of feeding
- More eaten faster passage time - less time for digestive action of enzymes gives lower apparent digestibility
- Mainly affects slowly digested components eg cell wall - fibre
What affects grass digestibility
Grass digestibility decreases as grass grows due to more structural carbs and less storage carbs
Describe the impact of lignin on digestibility
High in wood, straw and hay
High resistance to chemical degradation
Will reduce digestibility of closely associated structural polysacchrarides e.g., cellulose
Name the fibre fractions of crude fibre
NDF - neutral detergent fibre
ADF - acid detergent fibre
MADF - modified acid detergent fibre
describe the composition of food
Water
Dry matter
- Inorganic (ash)
* Minerals
- Organic
* Carbohydrates
* Lipids
* Proteins
* Nucleic acids
* Organic acids
* Vitamins
What fractions is feedstuffs broken down into in proximate analysis?
Moisture
Ash
Crude protein (CP)
Crude fibre (NDF, ADF, MADF)
Ether extract (EE)
Nitrogen free extractives (NFE)
Define gross energy of feed
Total energy feed contains
What is digestible energy
Energy from food animal can access
remainder is mainly lignin & other indigestible compounds
What is metabolisable energy
energy available for utilisation by the animal
What is net energy
the proportion of metabolisable energy that can be used for maintenance, growth, lactogenesis, production of wool/hair, growth of a foetus
What is K factor & what does it mean
The conversion efficiency of metabolisable energy into net energy
Some energy is lost as heat during digestion and metabolism
k factor = NE/ME
What is heat increment
the difference between metabolisable energy and net energy
What processes lead to the production of heat increment
Chewing, rumination, digestive motor activity
Production and secretion of digestive juices
Hydrolysis and metabolism of nutrients in lumen and wall of GIT and active transport across
Metabolism of absorbed nutrients and synthesis of macromolecules
What is diet quality/metabolisability
the proportion of gross energy that is metabolisable
q = ME/GE
What is animal production level (APL)
how hard the animal is working above maintenance requirements
As production within animal increases why does efficiency factor (k) decrease
More food must be eaten => GIT transit time decreases => less time to extract available nutrients
Label the metabolisable energy system
What is metabolic rate
expenditure of energy per given time
What is basal metabolic rate
energy expenditure for basic life processes at rest
What is fasting metabolic rate
‘animal’ version of BMR
Usually higher than BMR as movement occurs
What is resting metabolic rate
amount of energy a non-production animal requires to live without gaining or losing weight
What is field metabolic rate
Average metabolic rate of an animal
includes energy required to hunt, graze, socially interact, reproduce
How do you calculate metabolic intensity
Metabolic rate/kg body mass
Metabolic rate tends to be higher in small animals
What is undegraded dietary protein
Protein that escapes digestion in rumen
Dependent on rumen outflow rate and protein source (some proteins more resistant to digestion)
What are the limiting AA’s in pigs & poultry
Pigs - lysine and methionine
Poultry - lysine, methionine, tryptophan
Describe the fractions of protein
What is rough grazing
common land
little or no additional inputs
Usually sheep & suckler cows
What is permanent pasture
Land in ‘grassland’ production
Often hilly & poorer fields with streams
Likely to have diverse plant species
Usually lower yielding but also lower inputs
What are short term leys/temporary pastures
Usually part of arable rotation
Better quality land
May include clover to enhance protein
What is continuous grazing
few fields rather than lots of paddocks
different fields grazed during day and night
Which type of field is most likely to be grazed with a continuous system
permanent pastures
What is zero grazing
grass is cut and carted to livestock daily
What are the pros and cons of zero grazing
Pros:
- high output
- grass quality can be controlled by cutting frequency
- integrated with silage making
Cons:
- high cost of machinery and labour
- risk of breakdowns
- no fresh faeces on pasture
What is rotational grazing
lots of paddocks
3-4 week rotations
What is a paddock grazing system
divides field into paddocks
rotate livestock to graze and rest grass
What is strip grazing & how can it be used to increase intakes & decrease spoilage
Use of temporary fencing to control access to fresh grazing
Allows restricted feeding and reduces waste
Prevents defecation/urination on fresh material
Allows extra grass to be conserved
How does paddock/rotational system integrate with conservation?
biodiversity preservation
soil health
water conservation
reduced chemical inputs
enhanced nutrient cycling
What is back fencing & what is the benefit
Temporary fences to protect recently grazed areas
allows quicker recovery
Good for weaning to gradually separate young animals from mothers
What are the pros & cons of no fence fencing
pros:
- flexibility in grazing management
- reduced physical barriers
- adaptability
Cons:
- relies on tech
- initial cost
- learning curve for animals
Why are leader/follower systems used in paddock or rotational systems?
Allows for high yielders to graze ahead of low yielders so they get all the nutrients they need
What is forward/creep grazing
allows small group (often young or lactating animals) to access pasture first to optimise nutrition of herd
What is poaching
damage to turf caused by feet of livestock
Where is poaching most likely to occur
highly-stocked fields in wet conditions
Around inappropriately or overflowing water troughs
How is poaching reduced on dairy farms where cattle are brought in to milk often
Well designed laneways/cow tracks
Rotational grazing
Strategic gate placement
Rest periods for pasture
Correct stocking density
Regular monitoring of pasture
Strategic water trough placement
What is deferred grazing? why do this?
leaving a section of pasture ungrazed for extended period
Improve biodiversity which enhances pasture quality
What is the difference between italian & perennial ryegrass? When would they be used?
Italian:
- completes lifecycle in 1 year and establishes quickly
- high quality forage but short lifespan
- used to provide high quality forage in winter months
Perennial:
- high quality pasture that grows slowly with long lifespan
- used for long-term pasture
Why would a patch high in clover be used for finishing weaned lambs?
clover is high in protein
compare rotational & continuous grazing in terms of controlling worm burdens
Continuous controls via prevention (worming)
Rotational controls via evasion
Describe grass hay
Produced by harvesting grass at early vegetative stage
High protein & digestible fibre
Grass is cut in field & left to dry in sun
Once dried it is baled into compact units for storage
describe grass haylage
Harvested earlier than hay
Baled with higher moisture than hay
Bales wrapped in airtight plastic to create anaerobic environment for fermentation
Higher nutrient retention than hay
Describe grass silage
Harvested at similar time to haylage
Grass cut & chopped into smaller pieces
Ensiled in airtight conditions for fermentation
Stored in silage pits
Describe wholecrop cereal silage
Includes entire cereal plant which is harvested at grain stage
crop is chopped & ensiled to preserve entire plant (including grain)
Suggest a grazing system for each example
What is chain harrowing
spreading faecal material and soil from poaching
What is topping
cutting off mature stemmy material to allow more young regrowth
What is clean grazing?
annual rotation of grass fields to different animals
Break worm lifecycles
Describe maize silage
Harvesting entire plant at milk stage
Chopped into small pieces & ensiled to preserve high energy forage
What is colostrum?
First milk produced after parturition
Yellow & thick due to it being high in fat & sugars
What does colostrum contain?
High in fat and sugars
High IgG, IgM, IgA
Neutrophils and macrophages
Why is colostrum so important to farm animals
Ruminants, pigs, camelids & equine have epitheliochorial placentas which don’t allow passage of IgG in utero
So all maternal IgG transferred via colostrum
Why is colostrum important to neonates
Gut health - stimulates neonates immature digestive system
Nutrition
Immunity
Prevent hypothermia - neonates have low % of adipose tissue so cannot thermoregulate properly
What is the role of each specific immunoglobulin found in colostrum
IgG:
- only Ig that can cross placental barrier
- absorbed across GIT to provide systemic protection
IgA:
- mucosal protection by prevention of pathogen attachment
IgM:
- first to interact with pathogens and cause agglutination
Describe the absorption of colostral IgG
By pinocytosis:
- Cells engulf IgG from intestinal lumen and transfer across lymphoreticular system
- enter bloodstream
2 isoforms:
- IgG1 and IgG2
- IgG1 is re-secreted into GIT lumen
‘gut closure’ at 24h of age as pinocytotic cells die
What is passive transfer
Process by which neonate acquires immunity via absorption of immunoglobulins
When neonates consume adequate amount of immunoglobulins, they are classified as having successful passive transfer of maternal antibodies
In contrast, if they are deprived of adequate colostrum, they are considered to have had failure of passive transfer (FPT) of maternal antibodies
What are the 5 Qs of colostrum management?
Quality
Quantity
Quickly
Quite clean
Quantify
What affects colostrum quality
premature/induced birth
Breed & age differences
Length of non-lactation period
- if less than 3 weeks results in poor quality colostrum
Time from birth to milking/stripping milk from mother
Disease
Poor BCS
What are possible sources of colostrum
Dam
Fresh but different dam (same holding)
Stored colostrum
Replacer-not supplement
Different animal species
describe storage of colostrum
Refrigeration
Frozen (do not thaw quickly as high temps will denature immunoglobulins)
Pasteurisation
What happens as a result of passive transfer of AB from colostrum
Health advantages
Reduces pre and post weaning mortality due to infectious disease
Increases daily live weight gain
Breeding animals have better fertility
Increased milk production in 1st and 2nd lactations
What are the implications of failure of passive transfer of AB from colostrum
short and long term health problems
Impacts on longevity
Increased risk of disease e.g., sepsis, neonatal scours
Increased risk of mortality
Stunted growth and development
how can colostrum quality be measured?
Colostrometer:
- measures specific gravity
- directly related to Ig content
- >50 mg/ml is good quality
Brix refractometer:
- measures protein fraction
- 22% brix = good quality
Why is it bad to give small amount of colostrum & wait to give the rest?
Initial amount can stimulate epithelial lining of SI to close so rest of colostrum cannot be absorbed correctly
How can we measure colostral antibody transfer
Brix refractometer used to measure protein fraction from neonates serum sample
Foal IgG snap tests (ELISA)
How can failure of passive transfer of Ab be corrected?
Serum transfusion:
- blood from healthy adult spun to harvest serum (containing antibodies)
- serum is transfused into neonate
Describe the differences between GIT of ruminating cattle & non-ruminating calves
Ruminating cattle:
- solid food source (concentrates and forage)
- 70-80% rumen size
- Numerous absorptive papillae
- pH = 6.2 - 7
- anaerobic microbiome for bacterial growth
Non-ruminating calf:
- liquid food source (milk)
- 25-30% rumen size
- no absorptive ability due to lack of developed papillae
- pH = 5-5.3
- sterile microbiome
What is needed to help rumen development
Inoculation and establishment of anaerobic ruminal microbial ecosystem
Initiation of starter feed consumption
Fermentation processes and absorption mechanisms
What stimulates growth of ruminal papillae
Presence of VFAs
What is paraketosis
Excessive development of papillae
What is the effect of low pH on rumen?
Undesired shift in microflora
Inefficient digestion
Decrease in rumen motility
increased keratinisation
Weaning = common time for low rumen pH because volume of starter intake increases
describe rumen microbiome development
Sterile in newborn calf
Gain bacteria from environment and colostrum/milk
Starch (concentrates) => increase in gram -ve bacteria
Fibre (forage) => increase in gram +ve bacteria
Compare Skimmed, whey and plant-based milk replacer
What are the aims of feeding solids to calves
Stimulate microbial population
Stimulate rumen papillae formation
Development of rumination
Increase rumen capacity
Provide energy
Impact behaviour
What is the aim of concentrate feeding in calves
Provide VFAs from starch:
- microbial fermentation
- rumen epithelial development
- provide energy
Describe how to concentrate feed calves
small amount offered from day 3 after milk
Consumption starts at 2 weeks
Energy source at 3 weeks
Rumen functioning at 10-12 weeks
Calves housed together => learned behaviour
What are the aims of forage feeding calves
High fibre and lignin:
- development of ruminal muscular layers
- mitigate low rumen pH
- establishment of microflora prior to weaning
- chopped to 3-4cm long - improves intake of concentrate
Introduced from day 3
should be available by 2 weeks
Why is water consumption important in calves
Early water consumption is important for:
- Rumen development
- Improved grain fermentation
- Better starter intake
- Provision of some GI bacteria
Offered from day 3 of age (ideally available from birth)
What are we looking for at weaning?
When are beef calves normally weaned
6-8 months
When should creep feed be introduced to beef calves and why
6-10 wks prior to weaning:
- reduces stress
- minimise drop in performance
- reduce pneumonia risk
When are dairy calves normally weaned
Min of 6 weeks of age
Common 8 weeks of age
What is step-down weaning in dairy calf weaning
Encourages starter intake during pre-weaning period
25-50% reduction in milk 10-14 days prior to weaning
2nd reduction 5-7 days pre-weaning
Increased solid feed consumption =>
- rumen development
- higher starter intake
- high BW gain after weaning
What are signs of problems with transition at weaning
reduced growth rates
GI issues e.g., bloat or diarrhoea (Scours)
increased levels of disease e.g., pneumonia
Describe the diet of dairy calves at:
0-8 weeks
8-10 weeks
10 weeks +
Describe the diet of beef calves at:
Birth
Run up to weaning
Weaned
Describe the diet of lambs at:
Birth
Weaning
growing
Why should silage feeding be avoided in growing ruminants
rumen cannot utilize silage properly until it is fully functional
What is the target growth for calves
0.8kg per day
55-60% mature BW at 13-15 months
What is the target growth for lambs
250g per day (min)
Wean at ~12-14 weeks
60% mature BW at mating at 18-20 months
Compare homegrown forages to purchased feeds for dairy cow diets
How much does a lactating vs dry cow eat in a day
Lactating:
20-25 kg dry matter per day
Dry:
12-16 kg dry matter per day
Describe total mixed ration (no individual feeding) feeding system of dairy cows
All concentrate feed is mixed with forage and fed with ad lib access
All cows in same group get exactly the same each day
Describe individual feeding systems of dairy cows
Ad lib access to either sample forage or mixed ration of forage plus concentrate
Additional concentrate fed via milking parlour or out-of-parlour feeding stations
More scope to tailor ration to specific cow
Concentrate feed is in 2 large meals
What are the effects of negative energy balance on dairy cows
Reduced milk quality
Decreased fertility
Impaired immune function (=> metritis, mastitis)
Role in other disease e.g. LDA
How can you prevent negative energy balance via feed in dairy cows?
maximise feed intake pre and post calving
Formulating appropriate pre and post calving diets:
- easy to over-feed during dry period
- need high energy density after calving
Describe hypocalcaemia in dairy cows & how it can be prevented
Sudden increase in Ca demand at calving => hard to mobilise stores rapidly => blood Ca conc can fall => skeletal and smooth muscle cannot contract properly
Feeding in last 3wks pre-calving:
- DCAB manipulation
- Calcium restriction
- targeted supplementation
How is rumen acidosis prevented via feeding in dairy cows
good feed intake to supply energy (rather than high energy density)
Sufficient ‘long’ fibres
Avoid large concentrate (starchy) meals
What are the essential vitamins of ruminants
A
D
E
Define deficiency (nutrition)
Define imbalance (nutrition)
Define interaction (nutrition)
Define micro or trace element (mineral) (nutrition) + examples
Define macro-element (mineral) (nutrition)
Define essential nutrient
Define bioavailability (nutrition)
Define pica (nutrition)
What are the essential macro and microminerals
Why are ruminants more likely to suffer mineral problems
rumen is not optimised for digesting minerals
What is the impact of high calcium on other macrominerals in large animal dites
Increased uptake of molybdenum
Lowered manganese, zinc, copper and cobalt
Reduced magnesium absorption
What is the impact of phosphorous in excess of calcium in large animal diets
Inhibits absorption of calcium
Ideal Ca:P = 2:1
What is the impact of high potassium on other macrominerals in large animal diets
Inhibits magnesium absorption
What is the impact high cations (esp. K & Na) on other macrominerals in large animal diets
Inhibits calcium mobilisation
What is the impact of high sulphur on other macrominerals in large animal diets
Inhibits absorption of selenium
What is the micromineral interaction between iron and manganese in large animal diets?
Iron reduces manganese availability
What is the effect of selenium deficiency on other microminerals in large animal diets?
leads to iodine deficiency
Describe copper interactions in the ruminant
Sulphur and molybdenum form thiomolybdate => attract copper, making it unavailable (secondary deficiency/ ‘lock up’)
What are vitamins
Which vitamins are water soluble & fat soluble
Water soluble:
C, B
Fat soluble:
A, D, E, K
describe the effect of sulphur toxicity & vitamin B1 deficiency in ruminants
Elevated rumen sulphide conc (from diet) destroys microbial B1 (thiamine)
Functional B1 production halted by increased thiaminase-producing bacteria
B1 deficiency disrupts enzymes in energy metabolism pathways
Damages superficial brain tissue due to altered glucose metabolism
=> blindness, mal-coordination, lethargy, seizures
Describe vitamin B12 synthesis in ruminants
Rumen microbes synthesise B12 from dietary cobalt
B12 absorbed in intestine, transferred, to blood, stored in liver and muscles or secreted in milk
Describe the mineral audit
What do samples collected from animal in mineral audit indicate
Concentrations in blood used to detect deficiencies
Enzyme functions used for microminerals at marginal or normal concs
Liver concentrations show accumulation and depletion
Urine can show dietary supply or excess
When doing a mineral audit how many samples should we collect? From which animals? And which should be avoided?
What is the role of calcium, the signs of a calcium deficiency and its risk factors?
Role:
skeletal formation, milk production, nerve function
Signs:
Tremors close to birthing
Depressed and abnormal growth in young stock
Weak bones
Spontaneous fractures
Risks:
older mothers
reduced dry matter intake
low Mg, high P, low Ca feeds
What is the role of phosphorous, the signs of its deficiency and its risk factors?
Role:
Skeletal formation, energy utilisation and metabolism
Signs:
Reduced growth, decreased appetite, reduced milk production, fragile bones (osteomalacia)
Risks:
older mothers
mature pastures
AI contamination
low soil phosphorous
What is the role of magnesium, the signs of its deficiency and its risk factors?
Role:
muscle control, nerve function, enzymatic function
Signs:
anorexia, decreased feed intake, un-coordinated movement, muscle twitching
Risks:
high K or N (fertiliseed pasture)
Spring grass
Cold snaps
stress
What is the role of iron, the signs of its toxicity and its risk factors?
Role:
Blood cell formation and enzyme activity
Signs:
inhibits copper absorption, bacterial infection, diarrhoea, reduced feed intake, weight gain
Risks:
high Fe pastures
soil contamination of silages
What is the role of copper, the signs of its deficiency and its risk factors?
Role:
Enzyme systems, respiration, fertility
Signs:
anaemia, fragile bones, infertility, delayed oestrus, reduced immune function, neonatal ataxia, hair and pigmentation loss, ill-thrift
Risks:
low pasture Cu
high levels of antagonists in diet
What are the signs of copper toxicity and what are its risk factors
haemolytic crisis (jaundice, haematuria)
risk factors:
- stressors
- illness
- species & breed
What is the role of cobalt, the signs of its deficiency and the risk factors?
Role:
Vit B12 production
Signs:
B12 deficiency, poor immune function, pale skin and mucosa, ill-thrift
Risks:
youngstock
lush grazing
dry weather
What is the role of selenium, the signs of its deficiency and its risk factors?
Role:
Antioxidant
Signs:
White muscle disease (wasting), poor repro performance, ill thrift, stiff gait, weak calves
Risks:
youngstock
high rainfall
lush pasture
phosphate fertiliser
clover-based sward
What is the role of iodine, the signs of its deficiency and its risk factors?
Role:
metabolism
Signs:
Goiter, reduced fertility, hairless calves
Risks:
low iodine during gestation
goitrogens in feed
high rainfall
What are the signs of lead toxicity and its risk factors
Anorexia
Rumen stasis
Colic
Constipation followed by diarrhoea
If severe poisoning: neurological signs, blindness, head pressing, loss of co-ordination
Risks:
contact with lead-containing objects or ingestion of lead contaminated soil
What is the role of vitamin A, the signs of its deficiency and the risk factors?
Role:
vision, bone growth, immunity, maintenance of epithelial tissue
Signs:
night blindness, poor growth, poor coats, suppressed immunity, retained placenta, impaired fertility
Risk:
youngstock
pasture in drought
lack of green pasture at parturition
breed
stress
What is the role of vitamin D, the signs of its deficiency and the risk factors?
Role:
Ca and P metabolism, immune function
Signs:
soft, porous, poorly developed bones (rickets)
inappetence, decreased growth, stiff gait, stillborn and deformed calves
Risks:
youngstock
year round housing
heavy coated, thick wooled and dark pigmented animals
What is the role of vitamin E, the signs of its deficiency and the risk factors?
Role:
antioxidant, immune function and development, muscle growth
Signs:
Poor immune status, muscular myopathy, white muscle disease
Risks:
youngstock
drought
lack of green pasture
What is the role of vitamin K, the signs of its deficiency and the risk factors?
Role:
blood clotting factors
Signs:
poor blood clotting, internal bleeding, haemotoma
Risks:
mouldy silage
What are the possible causes & solutions to lambs not growing as quickly as they should be?
Worms - worming them/move them to different field
Poor pasture quality - rotate pastures & ensure pastures have enough time to rest, increase biodiversity
pasture management - leader/follower with pre-weaned lambs to make sure lambs get enough nutrients & eat clean grass
colostrum - ensure all lambs have colostrum within 6 hours of life
pasture size - ensure pasture is big enough so all lambs get enough nutrition
What are common differentials for diarrhoea in neonatal horses
foal heat
rotavirus
salmonella
clostridia
What are the common differentials of diarrhoea in weanling horses?
parasites
What are the common differentials for diarrhoea in adult horses?
clostridia
salmonella
parasites
antibiotics
What are common differentials for diarrhoea in dogs
Gastritis/enteritis
parasites
foreign body
IBD
allergy
neoplasia
kidney failure
endocrine disease
What are common differentials for diarrhoea in lizards
endoparasites
protozoa
bacterial infection or overgrowth e.g., salmonella
Viral
Stress
Incorrect husbandry
What are common differentials for diarrhoea in sheep?
Nematodirus battus
coccidiosis
What is the recommended diet for pet pigs
~70% fruits and veg
~15% grains and cereals
~15% forages
What is the recommended diet for commercial pigs
Grains and cereals
Proteins
Fibre forages (alfalfa)
Supplements
What are the types of commercial pig feeds
What cant pig eats
Feeding processed animal protein & catering waste has been banned
What is the main source of energy in pig diets
Carbs - typically cereal grains e.g., corn, barley, wheat
describe fibre in pig diets
Inefficient digesters so aim for <5%
Useful during early gestation and maintenance
Can be used to slow growth or promote lean muscle over fat production in late finishing
Enrichment
Describe protein in pig diets
Lysine is first limiting AA so diets are formulated on a lysine bases (requirement decreases with age due to increased feed intake)
Cereal grains e.g., corn, barley
Describe lipids in pig diets
most dietary lipids absorbed are deposited directly into body fat
Linoleic acid only dietary essential FA
supplemental fats and oils added in summer to increase caloric density and maintain energy consumption during hot weather
describe vitamins & minerals in pig diets
Important macrominerals:
- Ca
- P
- Na
Suckling pigs require supplemental iron during 1st 3 days as milk is low in Fe
Describe digestion in piglets
GIT not mature until few weeks after weaning
Suckling and weaning pigs require highly digestible raw materials
- e.g. milk products or animal proteins
Can add prebiotics or probiotics
Describe creep feeding in piglets
Solid feed given during suckling aids intestinal development and eases transition
Introduced from 7-12 days
Aim for 300g of total feed intake per piglet before starting weaning
Highly palatable with large amounts of milk products
Feeding creep while sow is eating increases piglet creep intake
ad lib drinking water
describe weaners (pig) diet
Weaning is stressful, sudden diet changes reduce performance
Piglets are weaned at 3-5 weeks old
Intake in first few days after weaning is key
Same diet as fed pre-weaning for ~1 week or until 9 kg BW
Feeding milk replacer for short period after weaning can be beneficial to growth & gut health
Highly digestible ingredients (milk products, fish, processed cereals)
Describe starters (pig) diet
Most starter feed regimes are 2-3-stage, to ensure smooth transition onto grower ration
Young pigs have high nutrient requirement, & small appetite
Diets are high energy & protein, with minerals to support growth
As pigs age, their appetite improves & nutrient requirements decline as growth slows
describe growers & finishers (pig) diets
As pigs grow, feed intake increases accordingly
No longer require complex diets or specialty ingredients
High levels of protein
Rations include; wheat, barley & high protein soya
describe diet for dry sows & gilts
Gestating pigs should be fed according to body condition
Gilts are still growing, protein supply must support maternal & foetal growth
Sows (parity 2 onwards), reduced requirement for lysine & increased requirement for energy
Until mid-gestation foetal & mammary development is small, aim to maintain condition without over- or underfeeding
In late gestation foetal demands may increase intake by ~1 kg/day
Avoid overfeeding days prior to farrowing to avoid depressed intake during lactation
Describe diet for lactating sows & gilts
Sows have higher feed intake than gilts
Gilts may need greater nutrient density
What factors affect pig nutrition
Genetics - fast growing breeds require more protein e.g., duroc
Temperature:
- too hot => reduced feed intake and efficiency, increases muscle breakdown
- too cold => increases feed intake, more feed directed to heath generation => slow growth
What are over conditioned sows prone to
stillbirths
poor colostrum and milk production
piglet crushing
fewer parities
delayed return to oestrus
insufficient intake during lactation
What are under conditioned sows prone to
underdeveloped piglets
poor milk availability
abortions
failure to return to oestrus
fewer parities
Describe the nutritional effects of stress on young pigs
Villi shrink => reduced SA
Villus atrophy => crypt hyperplasia and increased intestinal permeability (leaky gut)
Describe the nutritional effects of cold temperatures on young pigs
Reduced intestinal peristalsis => increases ‘bad’ bacterial colonisation
What is milk diarrhoea in pigs
stronger piglets on front teats gorge on milk
What is a growth check in piglets
reduced intake post-weaning for ~7-10 days due to stress => diarrhoea and increased mortality risk
Why is it important to get a down cow into a sternal position as quickly as possible?
decrease pressure on organs/rumen turnover
Muscle/nerve damage can occur
What are the MSK differentials for a recumbent cow
lameness
muscle wastage (-ve energy balance)
dislocated hip
tendon/ligament rupture
What are the GI/metabolic differentials for a recumbent cow
Low Mg (staggers)
Milk fever (low Ca)
Ketosis
Acidosis
Fatty liver disease
Toxicity
What is grass staggers
Mg deficiency/hypomagnesaemia/grass tetany
What are the clinical signs of grass staggers
Hyperaethesia (sensitive to noises)
Anorexia
High BPM
Uncoordinated movements
Twitching
Spasmodic urination and defecation
Seizures and sudden death
Teeth grinding
excessive salivation
How can grass staggers be tested for
What effect does hypomagnesaemia have on calcium metabolism
Decreased Mg => cAMP production => PTH secretion decreased => less Ca
