Feeding young ruminants and pasture management

what is colostrum?

• the first milk post parturition

what does colostrum contain that’s so important?

• igG

• IgM

• IgA

• macrophages and polymorphonuclear neutrophils

how much does colostrum does a calf need

• 10-12% bodyweight

• 3-4 litres

what is transition milk?

• subsequent milk after colostrum for the next 4 days

why is it important calves/lambs receive transition milk

• it helps increase SA of SI, subsequently helping nutrient absorption

• short term DLWG is improved

what are some benefits to feeding milk replacer

• reduces cost for the farmer

• has higher milk solids % than cow milk

• heat treated, killing bacteria

why is skimmed milk the best milk replacer?

• high in milk protein casein

  • this protein forms a clot in the abomasum, helping the calf feel fuller for longer

what should we install in a calf stall to help during the pre-weaning period?

• roughage

• concentrates

• milk

• water

what roughage should we provide during the pre-weaning period?

• hay/straw

• forage

why should we provide roughage to pre-weaned calves?

• helps the rumen develop

why shouldn’t we give pre-weaned calves silage?

• they can’t digest it! not until 6mo of age

by what age should we be providing pre-weaned calves with forage

• 2 weeks

by what age should we be providing concentrates to pre-weaned calves

• from day 3, ideally from 2 weeks

by what max age should calves have access to concentrates

• 3 weeks

why should we provide pre-weaned calves with water?

• it’s 70-75% of their bodyweight

• increases growth

• increses start intake

how much water should calves be provided with/drink by:

1. 1st week

2. 3-4 weeks

1. 1L/day

2. 3L/day

what method do we use for weaning

• step down method

for weaning, what do we do at 0-8 weeks

• whole milk replacer, 6L BID

• ad lib concentrate and forage

what do we do for weaning during 8-10W of age

• eat >1-2kg concentrate

• gradually decrease milk

• increase concentrate

• ad lib forage

what do we do for weaning at 10W+

• concentrate

• forage

• higher % of high E dense forage

what is rough grazing

• uncultivated land for grazing livestock

what is permanent pasture

• land used to grow grasses/herbaceous forage through cultivation. Not included in crop rotation for 5+ years

what are short term leys/temporary pasture

• high yielding and used for conserved forage; silage/haylage

what is continuous grazing

• animals graze for extended time with no/infrequent rest

what type of field is likely to be used for continuous grazing

• extensive field, hils, rangeland where stocking density is low

what is zero grazing?

• where grass is harvested and fed fresh to animals daily

what are advantages to zero grazing

• increases fresh utilisation

• cows are confined therefore more E used for milk than movement

what are disadvantages to zero grazing

• confined animals may be more stressed

  • increased incidences of lameness or mastitis

what is rotational grazing

• stock is moved around fields/paddocks, intensive grazing followed by a period of rest for the ground

what is a paddock grazing system

• field divided into smaller paddocks and animals are moved around in these

how does paddock grazing integrate with conservation?

• the rest of the field can regrow and not be overgrazed

what is strip grazing

• field is divided into strips and as it’s grazed, it’s slowly widened to allow access to the rest of the field

why may we use strip grazing?

• helps control grass intake, have fresh, higher quality grass available over longer time

what other crops are often grazed when using strip grazing?

• grass

• wheat

• radishes

• clover

• cereal rye

what are the benefits of back fencing

• controls the supply of pasture ready for next grazing

what is back fencing

• temporary fences used to protect recently grazed pastures from back grazing

what is a leader/follower system

• where pasture is grazed by one group, then another, then rested

what is creep grazing

• smaller animals go from one pasture to another via gaps in fencing

what are advantages of creep grazing

• allows smaller animals e.g. lambs/calves to access better quality grazing, helping maintain performance

what is poaching

• damaging grass + underlying soil by livestock that are on it for prolonged periods, often wet conditions

where is poaching most likely to occur?

• in wet fields + gateways

what can we do to reduce poaching on a farm

• use strip grazing and backing fences

how do we determine level of dry matter in a field?

• use a sward stick to measure height of the grass, which indicates average cover for the field

what is deferred grazing

• remove livestock from pasture in late august/early september to allow grass to grow the feeding in mid-november

why is deferred grazing good?

• allows the grass to grow without risk of animals coming back before its replenished

• reduces winter feeding costs

why use high clover sward for weaned lambs?

• high protein and energy

  • good for DLWG

how do herbal lays improve soil structure and health?

• provide resilience during dry periods and extends the grazing system

how does continuous grazing affect worm burden

• increases it as eggs remain on pasture which is eaten

how does rotational grazing affect worm burden

• allows animals to move b4 eggs hatch and larvae are ingested

what pasture is likely to ahve the highest worm burden?

• one that’s had lambs/ewes and lambs

what happens around urine and faecal deposits in grazing?

• lots of grass growth and nutrient cycling in the soil due to high nutrient loading

How is hay produced?

• grass is cut

• spread out and left in the sun to dry

• reduces moisture to 20%

• baled

how is grass haylage produced?

• cut grass earlier than for hay

• wrap in anaerobic environment

• high water content

• allow to ferment before feeding

how is grass silage produced?

• grass is cut

• left to wilt

• harvested

• treated with additives

• clamped

• fermented

• squeeze out as much air as possible

how is crop cereal silage produced?

• ferment crop in a clamp after harvesting

• lactic acid produced preserves the crop

what is maize silage?

• harvesting at optimum dry matter

• treat with additives to prevent losses from inefficient fermentation

• clamp

• leave to ferment

what would be an appropriate grazing system for ewes during early pregnancy before scanning?

• strip or leader/follower system

• this allows controlled grazing, ensuring adequate nutrition for pregnant ewes and prevents overgrazing of entire pasture

what would be an appropriate grazing system for ram lambs at 10 weeks with a target finishing at 14 weeks

• intensive rotational grazing by paddocking the pasture

• swap every few days, giving them fresh, high-quality forage, promoting growth and avoiding over grazing

what would be an appropriate grazing system for a small holding of 6 ewes and 2 alpacas for busy owners?

• simple rotational grazing system

how do we get dried grass?

• havest grass frequently, every few weeks

• taken into industrial drying ovens

• sold as chopped dry grass/milled

how does the composition of grasses and cereals relate to their nutrient composition?

• all values increase but the cell content values decrease in total proportion compared to the cell wall content (40:60%)

what are 3 types of grass growth

• vegetative growth

• reproductive growth

• vegetative reproduction - tillering

what are 2 types of ryegrass

• italian ryegrass

• perennial ryegrass

what are 2 types of clover, what type of plant is this?

• white and red

• legumes

what is a risk with clover-rich swards?

• frothy bloat

Compare these in cavles and cattle:

1. rumen capacity

2. papillae presence

3. pH

4. microbiome

1. 70-80% in adults, 25-30% in calves

2. none in calves, numerous in adults

3. 6.5-7 in adults, variable in calves (lower)

4. anaerobic in adults, sterile at birth in calves

what 3 things are needed to help rumen development

1. inoculation + establishment of anaerobic microbial ecosystem

2. initiation of started feed consumption

3. fermentation process + absorption methods

papillae growth:

1. what are they

2. what’s their importance

3. what stimulates their growth

4. what do we call excessive growth

1. small finger like projections

2. absorption of VFA

3. presence of VFA

4. parakeratosis

4 impacts of low rumen pH

1. undesired shift in microflora

2. inefficient digestion

3. decrease rumen motility

4. increase keratinisation

when is there an increased risk of low rumen ph?

• weaning time

how do these nutrients affect the rumen microflora:

1. starch

2. fibre

1. increase in gram -ve bacteria

2. increase gram +ve bacteria

what VFA do these produce:

1. gram -ve bacteria

2. gram +ve bacteria

1. butyrate and propionate

2. acetate

liquid whole milk:

1. where does the milk come from

2. what shouldn’t these cows have received

3. pasteurise?

1. cows on farm

2. antibiotics

   1. farmers choice

pros of liquid whole milk?

• increased fat content

• lower labour

cons of liquid whole milk

• fluctuate solid %

• MAP transmissionr isk

• cost

what are pros of milk replacer

• consistent solids %

• cost

• heat treated

what are 3 cons of milk replacer

1. lower fat content

2. higher lactose content

3. labour intensive

skimmed milk replacer:

1. contains?

2. by-product of?

3. con?

1. all major milk proteins e.g. casein - forms a clot!

2. butter and cream manufacture

3. expensive

whey MR:

1. contains

2. by-product of

3. con?

1. lactose, 15% whey protein

2. cheese manufacturing

3. no functional abomasal clot

plant-based MR:

1. contains

2. con?

1. non-milk based proteins

2. not always easily digested

what is the legal feeding requirement for calves <1mo

• at least 2x/day

how much do we feed calves (<1mo?)

• depends on DLWG desire, weight, age, env conditions

• 750-900g/day = 150g/L MR in 6L

why do we provide young calves with concentrate?

• microbial fermentation

• rumen epithelium development

• energy provision

what is the main component of concentrate feeding?

• starch - 40%

when do we offer concentrate feeding?

• from 3d of age after milk

  • start consumption at 2 weeks

  • energy source from 3 weeks

why do we feed calves forage?

• develop ruminal muscular layers

• mitigate low rumen pH

• establish microflora prior to weaning

when should we start calves on forage?

• introduce at 3 days

• available by 2 weeks of age

how should we present forage to calves?

• chop length to 3-4 cm, available ad lib

why do we want calves to have access to straw/silage/hay

• help develop rumen papillae by causing abraisions

• but prevents hyperkeratosis as well

4 reasons water is important for calves

1. rumen development

2. improved grain fermentation

3. better starter intake

4. provision of some GI bacteria

how much water does each calf need per kg DM consumed?

• 5L

why should we provide straw/hay/silage ontop of the bedding

• so that they don’t eat their bedding

at what age do we separate bull calves from the dam?

• 6-8mo

why do we separate bull calves at 6-8mo?

• feeding calf directly is more efficient

what risk does removing the bull calf from her dam at 6-8mo pose?

• risk of losing BCS

when do we introduce creep feed to beef calves?

• 6-10weeks before weaning

why do we give bull calves creep feed access at 6-10 weeks of age?

• reduce drop in performance

• reduce pneumonia risk

what should the composition of beef calf creep feed be?

• 14-16% crude protein

• 12.5MJ ME/kg DM

how do farmers know when a calf is ready to be weaned?

• when they’ve doubled their BW since birth - use height as an indicator

what is the minimum age for weaning

• 6 weeks