Nutrition Flashcards
What % of sheep are in upland vs lowland?
50:50
What % of variable costs are lowland sheep feed costs?
60-75%
What is growing season like in hills/upland?
Short
When must hill/upland sheep gain weight for the winter?
In the summer
Minimum BCS for a hill/upland sheep?
2
What does “sent to tack” mean for hill/upland ewe lambs?
Wintered on better land
When are hill sheep usually only supplemented?
Bad weather
What feeds are given to hill sheep from 8 weeks old?
Hay, feed blocks, concentrates
What is supplemented in lactating hill sheep?
Magnesium
Until which month are feed blocks used in hill sheep?
May
How many lambs per year should hill sheep have?
One
When are lowland sheep on grass?
Spring to Autumn
What food should you give to lowland sheep in Autumn?
Fodder, root crops, byproducts
What food should you give lowland sheep during winter and at lambing?
Stored root crops
What should you feed store lambs?
Arable crops and byproducts
When should you feed ewes concentrates?
Late pregnancy and lactation
What should you feed fattened lambs?
Concentrates with minimal roughage
What is silage from mature grass like?
Low digestibility and crude protein
What is the risk if silage isn’t properly fermented?
Listeriosis
What is the minimum dry matter than hay should be?
85%
Risk if dry matter of hay is too low?
Mould and mycotoxin
What is the minimum digestibility hay should be?
60
How does digestibility of grass change with time?
Falls with grass maturity
What is the minimum crude protein hay should be?
14%
What mineral is often added to sheep concentrates?
Magnesium
Why should you not use cattle feed for sheep?
Too much copper - stored in liver
What is in home mix (for sheep)?
Cereal with protein/mineral balancer
Where is the protein from in home mix?
Fishmeal, soya, maize
What is the problem with home mix for sheep?
Maize gluten palatability
What happens to sheep if you use ground cereal?
Get acidosis
At how many weeks does the sheep embryo implant?
3-4 weeks
During which days does the sheep placenta develop?
30-90
Why should sheep lose condition during placental development?
To optimise placental growth
During which days should sheep be scanned?
70-90
How much sheep foetal growth is in the last trimester?
90%
How much sheep foetal growth occurs within the last month?
60%
During which time period does the sheep mammary tissue develop?
Last 30 days
What should feed be like in late sheep pregnancy?
High dry matter and digestibility
What is the minimum % digestible undegradable protein should be? Why?
At least 30% so bacterial protein can be used for energy
What should sheep BCS be in 1st month?
1-1.5
What should sheep BCS be in 2nd/3rd month?
2.5-3
How much BCS is it acceptable for a ewe to lose in late pregnancy?
0.5
Compared to maintenance, how much does sheep energy demands rise during lactation?
3x maintenance
How much milk does a 5kg lamb need per day?
1L
What % crude protein does a lactating sheep need?
18%
How long after lambing does milk production peak?
3-5 weeks
After how long are lambs grass-dependent?
6 weeks
After how long are lambs herbivores?
8 weeks
What happens if dry matter is too low in lambs?
Scour
Which parasites can cause problems in lambs?
Coccidiosis and nematodirus
At what stage is ill-thrift common in lambs?
The stage when they are becoming grass dependent/herbivore
Lack of which nutrients affects lamb growth?
Cobalt, copper
Up to what age does the weight of a ewe increase?
3yo
Up until what age should you feed a ewe for weight gain?
18 months
How much of her mature weight should a ewe lamb be at breeding?
60%
How much of her mature weight should a shearling (2 tooth) be at breeding?
80%
What % should ewe lambs and two toothed ewes increase their weight by during pregnancy?
5%
What are mature rams usually fed?
Grass with hay during winter months
What is target BCS for tups at the start of tupping?
3.5-4
How long before mating should underweight tups be given concentrate?
6-8 weeks before mating
How many mls/kg of colostrum should lambs receive in the first 18 hours of life?
200
How many daily feeds of milk replacer should lambs receive?
3
What what age can creep feed be given to lambs?
7 days
On good grass, what growth rate can lambs achieve?
250g/day
After what month must lambs not finished be fed on forage crops?
August
Which foods are fed to store lambs as grass quality declines?
Cheap - grass aftermaths, crop byproducts, green forages, root crops
Why do you give store lambs iodine supplements?
To counteract goitrogens in kale or rape
What do brassicas contain that can cause haemolytic anaemia?
SMCO
Which feed can cause photosensitisation?
Rape
What growth rates can indoor cereal finished lambs achieve?
250-300g/day
How quickly to indoor cereal finished lambs reach 40kg (slaughter weight)?
90 days
How many kg of feed is required to take indoor cereal finished lambs from weaning to slaughter?
100kg
What triggers hypocalcaemia in sheep?
Stress
When are ewes commonly affected by hypocalcaemia?
Last few weeks of pregnancy or early lactation
Why does increasing dietary calcium not work to prevent hypocalcaemia in sheep?
Not calcium deficient, the problem is uptake from the gut
When do ewes most often get hypomagnesemia?
Parturition and early lactation
Clinical signs of hypomagnesemia in sheep?
Tetanic spasms and fits
How lost must you supplement magnesium for in sheep after lambing?
Several weeks
What is cobalt needed for in the sheep rumen?
B12 synthesis
Signs of cobalt deficiency in lambs?
Poor growth rate, ocular discharge, poor wool growth and quality, anaemia
Effects of cobalt deficiency in adult sheep?
Reduced fertility and lamb survival
How can you confirm a sheep cobalt deficiency?
Liver or plasma assay
What is the best way to give cobalt to sheep?
Oral bolus
Which minerals in the diet may block copper uptake in sheep?
Molybdenum, S and Fe
Why can copper deficiency occur after lime on pasture in sheep?
Increased pH of the soil increases the available molybdenum in the diet
WHen should you supplement copper in sheep?
Only if proven deficiency
Which copper preparations should be avoided in sheep?
Edatate or glycinate
Three ways to supplement copper in sheep?
Copper heptonate injection, oral capsules, soluble glass boluses
What is selenium needed for in sheep?
Enzymes that scavenge free radicals eg glutathione
Which feeds is vitamin E present in?
Green forages, grass silage, grains
How do fertilisers affect vitamin E present in food?
Increase growth rate of crop so decrease vit E
Which kind of feeds are commonly vit E deficient?
Root crops for pregnant ewes or poor quality roughage
Which treatments of feed decrease vitamin E?
Preservatives and caustic soda
How do oil seeds with high PUFAs affect vitamin E demand?
Increase
Which areas commonly get iodine deficient soil?
Away from the sea
Effects of iodine deficiency in sheep?
Infertility, stillborn lambs, high neonatal lamb mortality
What do iodine deficient lambs look like at PM?
Enlarged thyroid
How is iodine commonly administered to sheep?
Commercial mineral preparations and boluses
Why are pig diets processed and what is a problem with this?
To increase digestibility, but causes stomach ulceration
How do pigs digest cheap cereal byproducts like wheat bran?
In caecum to use fibre
Where does the protein in pig feed come from?
Legumes or milk powder/whey
Which kind of protein is illegal to use in pig feed?
Animal (but fish can be used)
Where does energy come from in pig feed?
Oil and fats like soya oil
What are the most important minerals in pig feed?
Ca and P (as dicalcium phosphate)
What is the problem with using beans and peas in pig feed?
Cause trypsin inhibition
Which is the rate limiting amino acid in pigs/the most important/runs out first?
Lysine
Which kind of pig has the lowest lysine requirement?
Lactating sows
Which kind of pig has the highest lysine requirement?
Creep/weaner
Which kind of pig feed is lowest in lysine so must be supplemented?
Cereals
How can you estimate the crude protein in a diet?
Nitrogen
What are the four point you should BCS a sow?
At weaning, service, mid-pregnancy, farrowing
Why should you BCS a sow at weaning?
Poorest condition here
What should you do if a sow BCS is too low at weaning?
Wait a heat
Why should you BCS a sow at farrowing?
To know if feeding strategy worked
Why should you restrict a sows feed just after farrowing?
To increase intake when it is really needed later
How many times per day should you feed a sow?
3x
When should you replace condition in a sow?
During the next pregnancy
What is the problem with high feeding a sow during pregnancy?
Low feeding in lactation and excessive weight loss = “milking off her own back”
How are boars treated with regards to feeding?
Like a dry sow
What are the problems with a thin sow at weaning (thin sow syndrome)?
Decreased ovulation, increased W-R interval, ulcers/pressure sores
What are the causes of thin sow syndrome?
Feeding too much/little in pregnancy, too little in lactation, bullying, cold, parasitism
How should you ideally feed the lactating sow?
Give high protein first then feed to appetite to increase overall feed intake (let milk production increase in line with requirements)
Which substances have the same effect as antibiotics in pig feed?
ZInc oxide and copper sulphate
What is the problem with using zinc oxide in copper sulphate?
Contaminate environment
Why do young pigs get post-weaning diarrhoea?
Lack enzymes to digest starch
What are the three properties creep feeds should have?
Highly digestible, high in nutrients due to low intake, palatable
What do creep feeds contain to make them highly digestible?
Cooked cereal and milk
What do creep feeds contain to make them palatable?
Sweeteners and flavouring
What do grower-finisher feeds need to provided?
High growth rate and maximum feed conversion efficiency
What is the daily weight gain of a grower-finisher?
600grams/day
What is the genetic potential maximum weight gain for a grower-finisher?
900grams/day
What are the problems with feeding dry pellets to pigs?
More expensive than meal, heat can remove some nutrients, can cause colitis
What are the adv/dis of dry meal for pigs?
Cheaper and doesn’t need processing but more dust and waste
Why is liquid feeding for pigs cheaper?
Can use things it would otherwise be difficult to incorporate
What is it illegal to use in liquid feed for pigs?
Catering waste or animal by-products unless it is treated
How does liquid feeding for pigs affect gut flora?
Increases acidity which improves gut flora
How does liquid feeding in pigs affect phosphorus availability, digestibility and FCE?
Improves all
What is the problem with floor feeding pigs?
Cheap and natural but wasteful
How much room should pigs have at troughs?
Enough room for all to feed at the same time
What specific minerals do pigs require?
Ca, P, Zn, Fe, Se
Which specific vitamins do pigs require?
A, D, E, thiamine, riboflavine, pantothenic acid
Which vitamins do pigs require which are water soluble?
thiamine, riboflavine, pantothenic acid
What is the result of calcium deficinecy in growing pigs?
Poor mineralisation at fractures especially at slaughter
What are the signs of calcium deficiency in first-litter gilts?
Dog sitting and fracture
How do you treat first-litter gilts with calcium deficiency?
Remove litter and give IV calcium
What does iron deficiency cause in piglets?
Hypochromic microcytic anaemia
What is the iron requirement of a piglet and what does the sow supply?
15mg/day vs 1mg/day
By what age will iron deficient sows show clinical signs?
Three weeks
What are clinical signs of iron deficiency in piglets?
Hairy, pale/yellow, lethargic, prominent apex beat, dyspnoea, sudden death
At PM, what does an iron deficient pig look like?
Pale, watery blood, enlarged heart, pale enlarged liver
How do you treat iron deficiency in piglets?
Iron dextran or glyptoferrin
How do you prevent iron deficiency in piglets?
Dosing or sterile soil
What does zinc deficiency cause in pigs?
Parakeratosis
What are the causes of zinc deficiency in pigs?
Dry meal, earthenware troughs, excess phytate, high calcium
What are the clinical signs of zinc deficiency in pigs?
Depressed growth rate by 2-4 months, then reddish lesions under the thigh, fetlock, hindlimbs and back
How do you treat zinc deficiency in pigs?
Supplementation
What does vitamin D deficiency cause in pigs?
Rickets or osteomalacia during lactation
What are clinical signs of vitamin D deficiency in pigs?
Swollen costochondral junctions and growth plates lameness, distortion and collapse of joint surfaces
How do you confirm vitamin D levels in pigs?
Plasma assay
How do you treat vitamin D deficiency in pigs?
Increase dietary levels then supplement
What does vitamin E deficiency cause in weaned, rapidly growing pigs?
Sudden death, hepatosis dietetica, steatitis and infertility
What does chronic vitamin E deficiency cause in pigs?
Poor condition
At PM, what does a vitamin E deficient pig look like?
Good condition but pallor and excess pericardial fluid, sometimes a blood-filled peritoneum due to liver rupture
What does the heart muscle look like in vitamin E deficient pigs?
Reddened and streaked - “mulberry heart”
How do you diagnose vitamin E deficiency in pigs?
Plasma levels, sudden death, gross heart lesions, histopathology, liver levels
How do you treat vitamin E deficiency in pigs?
Parenteral or dietary vitamin E
What does pantothenic acid deficiency cause in pigs?
Goose stepping and eventual paralysis
How is pantothenic acid deficiency caused in pigs?
When animals receive bakery waste with no balancer
How do you treat pantothenic acid deficiency in pigs?
Multivitamins for goose-stepping but euthanase if paralysed
What are some common poisonings in pigs?
Salt, warfarin, bracken, mycotoxicosis
What are some examples of fungal toxins in pigs?
Zearalenone, vomitoxin, ochratoxin, aflatoxin, ergot
What does salt poisoning cause in pigs?
Convulsions, gait abnormalities, death
What are clinical signs of salt poisoning in pigs?
Pruritis, thirst, constipation, blindness, ataxia, head pressing
What % of salt poisoning cases in pigs results in death?
5%
What does salt poisoning in pigs look like pathologically?
Eosinophilic meningitis
What does the carcass look like in salt poisoned pigs?
High chloride
How do you treat salt poisoning in pigs?
Gradually restore water and euthanase those which are non-viable
How do you prevent salt poisoning in pigs?
Ensure enough water, monitor salt levels in waste food
Which kind of pig diets are prone to salt poisoning?
Whey and bread-based
What is the largest single variable cost in milk production?
Feed for the cattle
How much does feed cost per litre per cow per day?
24-33p
What five things does the energy in a cattle diet affect/cause?
Infertility, lameness, acidosis, LDA, protein level
What condition can a lack of protein cause in cattle?
Infertility
What does the amount of fibre in a cows diet affect?
Milk fat
What three conditions can dry cow feeding affect?
Milk fever, fatty liver, hypomagnesaemia
Which metabolites in milk, blood, urine, can be used to assess cattle nutritional status?
Urea-N, betahydroxybutyrate, glucose, non-esterified fatty acids
What % does feed intake contribute to underperformance in cattle?
66%
What % do feed and energy intake contribute to underperformance in cattle?
86%
What % do feed, energy and protein intake contribute to underperformance in cattle?
97%
How much BCS should a cow lose between calving and 60 days after?
0.5 max
What should BCS be at calving?
3
What should BCS be at peak yield?
2.5
What should BCS be 6-8 weeks before drying off?
2.75
What should BCS be at drying off?
2.75-3
Above what BCS change is associated with long term fertility effects in cattle?
0.75
How many cows should you sample for BCS and when?
5 cows in each of early lactation, late lactation and dry
What is the critical factor in cow ration formation?
How much a cow is eating
What three things influence how much a cow is eating?
The cow, the food and the management
What is the most difficult aspect to measure of a cow diet?
DMI
If not in calf, how much of the diet should be dry matter?
3% of weight or 2.5% of weight + 10% milk yield
What is the target DMI/day for a 700kg high-yield cow in late gestation?
12-15kg
What is the target DMI/day for a 700kg high-yield cow in peak gestation?
25-30kg
What is the equation to determine energy required by metabolic bodyweight in cattle?
0.86W^0.67
What is the approximate ME/day required by a cow?
65-70MJ
How much energy is required for each litre of milk in a cow?
5-6 MJ/kg
What should weight change be in early lactation?
None
When is the only time a foetus requires extra energy?
3rd trimester
In what kind of cow are pregnancy requirements an issue?
Dry cow
How many litres of milk should the ration be formulated for?
Maintenance + 20 litres
Which are the four groups of feed which provide energy?
Carbohydrates, fat, silage acids, protein
Which feed groups are not affected by the rumen?
Carbohydrates, and fats, esp maize
Do microbes absorb silage acids?
No
What do carbohydrates in the rumen become?
VFAs and gases
What is left for bacteria in the rumen?
Fermentable metabolisable energy
What do ruminal microbes do to starch and sugars?
Rapidly break down
What happens to the cow if too much starch and sugar?
Ruminal acidosis
What happens to the cow if not enough starch and sugar?
Microbes die
What is the only way lignin can be broken down in cattle?
Can’t unless treated with ammonia or hydroxide
What breaks down cellulose and hemi-cellulose in cattle? How quickly?
Enzymes and rumination - slowly
What happens to “protected fats” in cattle?
Pass into SI to be digested
What happens in cow given too much protected fats?
Coats fibre and disrupts rumen function
What are the two things that can happen to protein in cattle?
Either absorbed in SI and broken down in the liver for energy OR used to make microbial energy
What bacteria produces butyric acid and spoils silage?
Clostridia
Which acid does normal silage produce?
Lactic acid
What pH is normal silage?
4
What does mould growth do to silage?
Reduces palatability
What % DM is good silage?
25-30%
What can happen if silage or slurry enters a water course?
Microbial breakdown uses dissolved oxygen so fish die
What are three ways you can reduce effluent from silage?
Ensile at >25% DM, wilt before ensiling, don’t ensile in the rain
What should you dilute silage effluent to if you are spreading it on land?
1:1
How much silage effluent are you allowed to spread on land?
<25m3/ha
If you don’t want to dilute effluent, what else can you do to it before spreading it?
Aerate it
What is the problem with aerating effluent?
Increases greenhouse gases
What can you do to a slurry tank to reduce methan production?
Cover it
Over how long and how many cows and when should you monitor milk production?
10 cows over 1 month after peak lactation
Above what % decline of milk production in the month you study them indicates a nutritional problem?
10%
Where does milk protein come from and what does this depend on?
Microbial protein which depends on dietary energy
What reflects the long term energy status of a cow?
Milk protein
Which two types of protein make up the metabolisable protein?
Microbial + bypass
How much does an extra 10MJ of ME increase milk protein by?
0.03%
What are three ways you can increase the energy intake of a cow?
Maximise DMI during early lactation, use a mixture of forage to stimulate intake, feed more concentrates/maize
How should you prevent buytric silage building up?
Put it at the feed barrier and clean out the troughs each day
What three things can you supplement silage with?
Second cut silage, big bale silage or brewers grain
What is the maximum amount of concentrates you should give a cow per day?
6kg
What can you feed to increase milk protein due to the increased energy to the cow?
Bypass starch (maize)
How can protected soya be used in cattle?
Increases milk protein but only if dietary protein is limiting
What is a problem with using protected soya in cattle?
It will stimulate milk production so may exacerbate problems
Why would you give extra DUP in the dry cow ration?
To help increase milk protein levels
How fast is the response to dietary changes to increase milk protein levels?
Slow
When changing the diet to increase milk protein levels, what usually increases first?
Milk yield
What happens to farmers if milk quality is poor?
There is a penalty (reduced payment)
What are two advantages of increasing DMI in cows?
Improves FCE and reduces the methane produced per litre of milk
What is the advantage of increasing concentrates in cattle?
Reduces methane production but as a proportion of energy intake
Which diets produce the most methane in cattle?
High fibre
Which dies produce the least methane in cattle?
High concentrate
What % of cows should be ruminating while resting to indicate normal rumen function?
Over 60%
What is the ideal cud-rate?
50-80
What are two causes of a concave paralumbar fossa?
Low rumen fill or LDA
Below what pH is a rumen acidic?
5.8
How do you assess how acidic the rumen is?
Rumenocentesis
What are two causes of stiff faeces in cattle?
Slow transit time and a high fibre diet
What is gut health like with stiff faeces in cattle?
Can be good
What are two causes of loose faeces in cattle?
Rapid transit and low fibre
What is gut function like if loose faeces in cattle?
Sub-optimal
What causes osmotic diarrhoea in cattle?
Fermentation shifts to colon and caecum
How does decreased colonic pH affect the faeces?
Kills flora so fermentation ceases and faeces get harder
What do short fibres and absent grains say about rumen function?
Good
What does undigested grain say about rumen function?
Disturbed
What three things can undigested grain and long fibres say about rumen function?
Disturbed fermentation, poor harvesting or poor preparation
How much food should remain if you are feeding ad lib?
5-10%
What do fermentable and non-fermentable metabolisable energy become?
Carbohydrates
What two things does fermentable metabolisable energy become?
QFE and SFE
What are the QFEs?
Starch and sugars - non-fibre carbohydrates
What are the SFEs?
Cellulose and hemicellulose
Which four things provide the energy for rumen bacteria?
QFE, SFE, NH3, effective rumen degradable protein
Which three acids do rumen flora produce?
Propionate, butyrate, acetate
What processes do SFEs allow?
Saliva, buffering, rumination
What happens to acetate?
Produces milk fat via the mammary gland
What happens to propionate?
Turned into glucose in the liver
How does higher glucose affect the milk?
Increases milk protein and yield
What three things does urea contribute to?
BUN, milk urea and urine
What are the four functions of fibre in cattle?
Degraded by microbes for energy, promote rumination, forms rumen mat, produces acetate
What are two ways of measuring fibre content?
Neutral detergent fibre and acid detergent fibre
What does neutral detergent fibre measure?
Plant cell wall material
What does acid detergent fibre measure?
Cellulose and lignin
What does neutral detergent fibre correlate with?
Rate of digestion/DMI
What does acid detergent fibre correlate with?
Digestibility
How do you classify feed as cellulosic or non-cellulosic?
Neutral detergent fibre
What is the key factor in whether a food will stimulate rumination?
Physical form - long fibre 2.5cm-10cm
What tests can show how much “long fibre” a food contains?
Effective fibre, physically effective NDF, “scratch value”, structural value
Why is chop length an issue in silage?
Good silage must be chopped short quickly and then compacted
Which crop has especially short chop lengths?
Maize
If given teh chance, which fibre length will cows eat?
Short
What are the only two ways of assessing long fibre?
Visually by observing the diet mixing process or using a Penn State Forage Particle Separator
How many chews should there be before swallowing in a cow?
50-80
What is the problem if there are less than 50 chews before swallowing?
Not enough fibre or too short chop length
What is the problem if there are more than 80 chews before swallowing?
Too much fibre
What are four clinical consequences of irregular feed activity and TMR sorting?
Rapid transit times, sub-optimal gut function, loose faeces with undigested grains, fluctuations in rumen pH
What are three causes of reduced rumen pH?
Irregular feed availability, TMR sorting, slug feeding of concentrates in parlour
How does reduced rumen pH affect the milk?
Reduced production and fat
What are five consequences of too much non-fibre carbohydrates (QFE)?
Decreased rumen pH, decreased fibre digestion, increased acidosis, low milk fat, off feed
What is the problem with under-developed rumen papillae?
Can’t absorb VFAs
What are three causes of too much QFE (non-fibre carbohydrates)?
Insufficient fibre intake, excessive starches and sugars, inadequate saliva production
What is a cause of inadequate saliva production?
Reduced rumination times due to poor cow comfort
What is LF syndrome?
Low forage, low fibre, low milkfat, lame feet, low fertility
How long before calving should you acclimatise rumen flora to lactation?
3-4 weeks
How can you make long fibre more palatable?
Use molasses
What’s a problem with increasing rumen pH by adding bicarbonate?
Palatability
How can you increase cow saliva flow?
Free access hay
What does adding yeast do to the rumen microflora?
Removes oxygen and stimulates bacteria which digest fibre and use lactic acid
What are five consequences of sub-acute ruminal acidosis?
Reduced DM intake, reduced milk yield, poor milk quality, reduced fertility, disease
