PRECISION FEEDING IN DAIRY COWS-FEW CONCEPTS :
B.V.Sc &A.H ; M.V.Sc
Some of the important concepts of dairy farmers have to keep in mind while feeding their animals are given bellow,
The Dry matter (DM) requirement of cows: Unless the DM needs of cow is satisfied production and reproduction will be sub-optimal, hence DM requirements of a cow has to be carefully considered while planning any feeding regimen.DM requirements in cows depends upon their Body weights ,lactation and also the stage of lactation. The requirement of DM in lactating cows yielding is given bellow,
- Milk Yield 400-450 kgs
- 10 litres 2.6%
- 20 litres 3.4%
- 30 litres 4.2%
- 40 litres 5%
Lactation cycle: Understanding lactation cycle commercially and feeding dairy animals accordingly is very much important for a dairy farmer to run his farm successfully.
Lead Feeding (2 to 3 weeks pre-calving)
To allow rumen bacteria to adjust to changes in the ration, the cow should be started on some grain, and the level increased slowly before calving time. Two weeks before the expected calving date, increase the cow or heifer grain allowance to a maximum of 1% of her body weight as grain. This is lead feeding. By calving day, 4 to 5 kg for Holstein cows and 3 to 4 kg per day for Jersey cows is appropriate.
In Total Mixed Ration (TMR) fed herds, offer 6 to 8 kgs of the milking cow TMR as lead feed pre calving, plus green grass. Gradual adjustment to the milking cow ration is essential for keeping cows eating and healthy.
This is the first 60 days also called the profit period in the lactation cycle when the milk yield reaches its peak. During this period the cow cannot consume the DM requirement as per the needs of production due to certain physiological reasons leading to negative energy balance in high producers and the cows go down in condition.
Due to this suboptimal dry matter intake during early lactation the cow has to depend on her body stores for the nutrients to achieve peak milk yield. The adipose tissues witness a high rate of lipolysis and a very low rate of lipogenesis and the dairy animal is in negative energy balance leading to severe stress and poor immune status, making dairy cows and buffaloes are more susceptible for metabolic disorders and diseases.
A cow in early lactation can lose as much as 20 to 50 kg of fat in 6 weeks time, roughly equivalent to a newborn calf’s body weight. Feed containing high energy and protein must be fed during this phase alongside Rumen undegradable protein (Bypass protein).
Challenge Feeding (Early post-calving feeding) With proper lead feeding, you can get cows on full feed quickly after calving. For the first few days after calving, don’t increase the grain above what was offered pre-calving. Feed high quality green fodder and offer several pails of warm water to reduce the stress of calving. Keep the cow eating and the rumen full to prevent twisted stomachs and milk fever.
About 3 to 4 days after calving, challenge feed your cows and encourage high peak yields by increasing the feed offered. Offer a high protein feed in addition to the major grain (energy) feed in early lactation. Start the protein supplement during the first few days of lactation. Protein stimulates appetite and feed digestibility in the just fresh cow. Protein requirements in early lactation are high, at 19% of the diet DM. At peak milk production the protein requirement is 18%. Try to get cows up to the maximum amount of the high protein feed by 2 weeks into lactation.
Increase the grain fed gradually. Cows pushed too fast will go off-feed. Most cows can tolerate an increase of 1 kg every other day during the first week, 0.5 kg every other day in week 2 and 0.3 kg every other day in week 3. If lead feeding levels were adequate, this schedule will get cows to their maximum grain and protein intake by 3 to 3 1/2 weeks into lactation.
In TMR(Total Mixed Ration) fed herds where 2 milking cow rations (high and low production level) are fed, cows can be moved into either group. Feeding some TMR prior to calving, will help cows to adapt to high levels of grain in the TMR Keep cows eating by feeding TMR free-choice. Cows should have all the feed they want, when they want to eat it.
Mid lactation and late lactation:
Minimum forage to concentrate ration of 40:60 is suitable during mid lactation. More roughage (less grain) can be fed to cows in late lactation or at low production levels. Forage: Concentrate ratios above 80:20 can support 20 kg of milk yield if roughage quality is good.
Dry Cow Feeding (Dry to 3 weeks pre-calving)
Under ideal conditions, dairy cows produce milk during 305 days of the year and are dry the remaining 60. In reality, feeding for high production should begin during the dry period or towards the end of the previous lactation, since feeding in this period determines the peak lactation, reduces negative energy balance and also prevents metabolic diseases. With dry periods of 60 days, there´s enough time to regenerate the mammary tissue. Dry periods shorter than 30 days and longer than 70 days reduced lifetime productivity.
Dry cows should be in good flesh before the dry period begins. The cow is more efficient at restoring her own body condition when milking, than when dry. She should gain back lost body reserves during mid-to-late lactation. Cows should neither gain nor lose body condition while dry.
Daily grain allowance after dry off will depend on roughage quality. When roughage quality is poor, 1.5 to 2 kg of grain may be required daily to maintain cow body condition. If roughages are good, but cows are thin, 1.5 to 3 kg may be required to allow for moderate and gradual weight gain during the dry period.
A balanced dry cow ration should contain adequate fibre, protein, vitamins and minerals. A proper dry cow ration prevents metabolic diseases and retained placentas and keeps cows on feed at calving.
N.B : Collated from different sources
Dr. Unni Krishnan, Consultant at National Institute of Agricultural Extension and Management ( MANAGE) Hyderabad. Author at SR Livestock Services: SR TMR A complete Feed for Dairy cows veterinary doctor at Government of Kerala