level ii agricultural business operations. understand the reproduction cycle assess herd...
TRANSCRIPT
Level II Agricultural Business Operations
Understand the reproduction cycle Assess herd reproductive efficiency Understand the decisions involved in
developing a breeding plan◦ Bull selection◦ Selecting cow replacements◦ Bull and cow management
Gestation Length:Interval from conception to calvingAverage: 287 daysRange: 280-300 days
Oestrous Cycle Length:Interval from one heat to anotherAverage: 21 daysRange: 18-24 days
Calving Interval:Interval between successive calvingsAverage: 415 daysRange: 360-500 days+
Calving Calving
Pregnancy – 290 days
365 days
75 days
Breeding/Conception
Pregnancy – 290 days
Breeding ConceptionCalving Calving
400+ days
Calving - March/April/May
Service - June/July/August
Weaning - September/October/November
Dry period - December/January/February
1. Calving Interval (Cow)
Number of days between calvings
2. Calving Index (Herd)
Average of calving Intervals
3. Calving Spread
Days/weeks from first to last calf born
Two herds of 50 Cows
Herd A Herd BCalving index 380 days Calving index 415 days
Direct costs of cow slipping 35 days
£
Lost calf growth 35 x £1.80/kg = £63.00
Feeding an empty cow Av daily cost 50p x 35 = £17.00
Total cost £80/cow or £2.30 per day
Herd A advantage = 50 cows x £80/cow = £4000
Calving not being batched
Extra handling time
Managing extra groups
Replacing an empty cow
• Financial cost (heifer cost – cull cow value)
• Financial cost Breeding extra replacements
• Using a maternal bull on more cows
• Biosecurity cost buying in replacements of unknown disease status
Calving date slippageCalving date slippage
• Calf sold 1Calf sold 1stst October each year October each year
• Cow calves 1-3-11 - calf weighs 300kg at saleCow calves 1-3-11 - calf weighs 300kg at sale• Cow calves 1-5-12 - calf weighs 230kg at saleCow calves 1-5-12 - calf weighs 230kg at sale• Cow calves 1-7-13 - calf weighs 160kg at saleCow calves 1-7-13 - calf weighs 160kg at sale
• Eventually - Can’t get to calf sale as a cow Eventually - Can’t get to calf sale as a cow is calving!!is calving!!
Having a clearly defined calving period or periods
Labour◦ Less time supervising calvings.◦ Reduced risk of difficult calvings due to overfit cows◦ Bigger/more even batches of calves
Disease◦ Reduced disease spread from older to younger calves
Weaning weight◦ Calves born earlier are heavier at weaning
Marketing◦ More even batches of store cattle
Replacement heifers◦ More heifer calves at suitable weight for bulling
Housing◦ More calving accommodation may be needed.
Disease◦ More calves at same stage if disease breaks out
Marketing◦ All ready at same time – cash flow
Take the bull out!
Cow◦ Replacement rate◦ Selecting replacements◦ 2 year calving
Bull◦ Estimated Breeding Values (EBV’s)◦ Physical characteristics◦ Natural Service versus AI
Cows do not last forever and will leave the herd for a variety of reasons:
◦ Old/ Sick / Lame◦ Empty◦ Poor fertility (Late)◦ Poor productivity◦ Other undesirable traits
Herds should have a clear replacement policy and plan ahead
Suckler herds have a typical Replacement Rate of 15 – 30% (Average = 20%)
E.g. At 20% replacement rate, a 50 cow herd will require 10 replacements every year just to sustain itself
What characteristics are you looking for?◦ Hybrid vigour◦ Milk◦ Calving ability◦ Longevity◦ Size◦ Breed
Advantages Disadvantages
Bio-security Need Maternal bull/AI
Performance History Reduced cash flow
Can select genetics Limited supply
Cost
Advantages Disadvantages
Simple to manage Bio-security
Plenty of choice No control of genetics
Cost
Time sourcing
Most efficient ◦ One less batch of heifers◦ Can carry 13% more cows on the same resource◦ Additional calves per lifetime
Targets◦ Serve at min of 60% of mature weight
e.g. 650kg cow = 390kg at 15 months of age◦ Calve down at 85% of mature weight
E.g. 650kg cow = 550kg at calving 24months
Bull Selection Ease EBVs
Estimated Breeding Values◦ Genetic potential for number of traits◦ Comparison within breeds
◦ Maternal – Self Replacing Index Calving ease daughters Milk Gestation length Scrotal size (fertility) Fat depth
Estimated Breeding Values◦ Genetic potential for number of traits◦ Comparison within breeds
◦ Terminal – Terminal Production Index Calving ease direct 200, 400 & 600 day weights Muscle depth / eye muscle area Carcase weight
Physical Characteristics
◦ Health Status◦ “Correct” ◦ Good Locomotion◦ Temperament◦ High Libido◦ Conformation◦ Age
What should a normal bull be able to achieve?
◦ A 90 – 95% pregnancy rate in a group of 40 cows over a 9 – 10 week period.
◦ Young bulls (<2 years old) should only serve 20 cows in first season
AI or Natural Service ... ?AI or Natural Service ... ?
AI : Greater genetic progress due to better
genetics. Can match bulls to individual cows.
Detecting cows in heat can be difficult and time consuming.
How good is your AI technique – does it affect your herd conception rates?
AI or Natural Service ... ?AI or Natural Service ... ?
Bull - Natural service:Time saving - does all the heat detection
for you.Conception rates – potentially better.
Bull could have fertility problem. Genetic progress limited compared to AI. Danger – especially indoors.
Standing to be mounted
Chin-resting
Head mounting
SniffingLip-curling
Restlessness/Bellowing
CajolingSoliciting
Licking other cows
Hair loss/dirt marks
Not standing to be mounted
Secondary Signs of HeatSecondary Signs of Heat- Less Important Signs- Less Important Signs
Cows prioritise how they use their nutritional resources.
1. Produce milk for her calf2. Maintain her body condition3. Get back in calf
Decreasing priority
A good guide to nutrition Cows scored on a scale 0 - 5 Underfeeding → thinner Feeding more than requirements →
fatter Important at mating, calving and
weaning Can reduce feed costs Crucial to fertility
Condition Condition Score 2 2
Condition Condition Score 3 3
Can be carried out at 5-6 weeks Identifies empty cows
◦ Allow for planned culling◦ Prevents feed wastage
Identifies bull fertility issues Identifies twins
◦ Can adjust feeding Estimated calving dates
◦ Planning housing and feeding requirements◦ Weaning dates
Discuss herd fertility with your vet
◦Vaccination policy – BVD, Leptospirosis◦Mineral deficiencies◦Bull assessment (MOT)◦Biosecurity◦Individual problem cows
Breeding efficiency essential for profitable production
Targets◦ 365 Calving index◦ Calving heifers at 24 months◦ Use EBVs to produce high genetic merit
replacements and finishing stock Manage cow condition to maximise fertility