Nutritional Demands Of Pregnancy And Lactation In Dairy Cow (dairy Cow Life Cycle) Flashcards
How long should heifer earring ideally take?
2 years
Describe the life cycle of a cow
- Birth (calving)
- Neonate – first hours
- Milk feeding – pre-weaning
- Weaning
- Post-weaning
- Breeding
- Gestation
- Calving
- Lactating – post-partum
- Lactating – Breeding
- Lactating – pregnant
- Dry period (pregnant)
- Repeat 7-9 (× 3-4)
- Cull
Life cycle of dairy cow
1. Birth (calving)
Generally occurs at about 280 days post conception
Twinning – in high yielding up to 5- 10% - gestation period shorter (270d) in twins
Birthweight: 30 – 60 kg
-calf gets snatched away from mother ASAP. Gets moved as far away from mother as possible
Life cycle of a dairy cow
2. Neonate- first hours
Calves taken away to dry and clean pen- either individual or shared pens
Feeding colostrum ASAP (first milk) is essential –
Only source of immunity (antibodies or IgG)
Energy
Influence the entire life of the animal
Naval is dipped with iodine ASAP
What is the rule of 3Qs of colostrum
(And magic number)
Quantity: 4 litres
Quickness: fed in 4 hours
Quality: Milked out from the cows in 4 hours
Life cycle of a dairy cow
3. Milk feeding- pre-weaning
Calves fed milk until weaning (50-80 days)
Fed in bucket (with/without teat) twice daily / ad libitum
Together with milk introduce from 2 weeks of age:
-Calf starter (cake, concentrate)
-Roughage (hay, straw, …)
What kind of milk is given to calf
Whole milk/milk replacer
How much milk should be fed to calf
20% BW/day (8-10 litres/day)
What does introduction of roughage and calf stater at 2 weeks of age do for the calf?
-Improves growth rate (850g/d)
-Allows for a Better transition from milk feeding to solid feeding
- Weaning
At 60 days or so
Transition from milk feeding to solid feeding
Most stressful moment for calves
No other procedures or group changes
Do it gradually – step down
What is the target amount of concentrate a farmer wants to give to a calf
1kg of concentrate/day
What are the most common health problems occurring during first 4 stages of birth?
Diarrhoea
Pneumonia
Navel ill – Joint ill
Septicaemia, meningitis
Life cycle of a dairy cow
5. Post-weaning (growing period)
Often neglected part of the cycle
Calves from 2-3 months onwards
Fed a ruminant ration:
Forage + concentrate (16% Proteins)
Still want calf to grow 850g/day
Most common health problems occurring at post-weaning stage
Pneumonia
Gastrointestinal nematodes
Liver fluke
Lungworm
Dermatophytosis
Clostridial diseases
Infectious bovine keratoconjunctivitis
Life cycle of a dairy cow
6. Breeding (heifer)
Mate heifers at about 55-60% adult bodyweight
370 kg
13 months (HF)
125-127 cm at the withers (HF)
1-2% freemartin (twin with male)
Good repro performance:
Use Artificial Insemination (AI) Use AI with Sexed Semen
Calve down at 24months
Producing an alive female calf
Life cycle of a dairy cow
7. Gestation (heifer)
Nutrient requirement increase during pregnancy
-Not over feed – monitor BCS
-50% increase in late gestation
2-3 week before calving:
-Moved to the calving area where they birth (next to the calving cows)
-Fed a ration that makes them ready to start the lactation - ref Ca and energy metabolism
Life cycle of a dairy cow
8. Calving (birth)
Transition from dry period to lactation
Starts the most critical period in any cow’s life and the highest risk period for mortality and morbidity
Targets for heifers
98% of heifers born calving down at 24 months —>
85% of heifers born calving down at 24 months producing a heifer calf —>
Reduce death and disease
Maximise growth rate
Perfect repro performance
Life cycle of a dairy cow
9. Lactation
The first couple of months after calving see most cows descend into negative energy balance
Around what month do farmers look for peak milk production?
Around 1st month
Lactation curves of a cowdepends on what factors?
-affected by genetics, age and nutritional factors
-Curves are steeper in multipara and Holsteins (breed of cow)
Describe the lactation graph
Life cycle of a dairy cow
9. Lactating – post partum
Post-partum or fresh period = first 3 weeks after calving
Most critical moment of lactation
Common health problems (RFM, metritis, ketosis, milk fever), especially in multipara/2nd+ lactation.
Anoestrus, no ovarian function
Early lactation, 20-50 days in milk (DIM)
First ovulation occur at 2-3 wks postpartum but is often associated with silent heat (ie no signs of heat/oestrus) due to lack of pre-existing corpus luteum
Uterine involution
Cows should not be inseminated during this period, wait until 45-60 DIM - (Voluntary Waiting Period - VWP)
Life cycle of a dairy cow
10. Lactating – breeding
-Uterine involution should be complete by 30-35 DIM
-Maximal milk production coincides with period when we want the cow to become pregnant (ie from 45 to 100 days) = energy nadir
Life cycle of a dairy cow
11. Lactating – pregnant
A good dairy cow should be pregnant for most of her lactation (280 days out of the 305 d lactation)
Last 60 days of pregnancy = dry period…
Life cycle of a dairy cow
12. Dry period (pregnant)
Standard 60 days First 40 = far-off dry Last 20 = close-up
Rest for the mammary gland
Less nutritional demand
Less competition
Life cycle of a dairy cow
13. Repeated calving and lactation
A common but usually unattainable target is to produce one calf per cow per year – this equates to a Calving Index (CI) of 365 d
To achieve CI 365 d = the calving to conception interval (CCI) must be 365 d – 280 d (gestation period) = 85 d (50 PP + 35 breeding)
This means first (successful) insemination must be before 85 d (CCI) – 21 d (interoestrus interval) = 64 d.
In practice, values of CI ~ 400 d are more commonly seen and probably more desirable
In strictly seasonal calving herds, there is a stronger imperative to have CI = 365 d (else cows fall out of synchrony with each other and results in severe efficiency loss).
Life cycle of a dairy cow
14. Culled/dead
Mortality
Total loss for the farmer – Target less 3%
Culling:
Most cows are killed before they would die of natural causes. The only reason for culling cows is ‘the cow is not productive in my herd anymore’.
We still refer to the term of involuntary or forced culls and the main reasons are
Mastitis
Lameness
Infertility, …
Voluntary culls would be those where a cow is culled because her production was below expectation or where her type is poor.
The idea is to minimise the rate of involuntary culls so as to maximise the opportunity to replace cows of relatively low genetic merits.
Some people think that more cows culled=…
Better management
