In the four weeks coming up to calving, the silage intake of cows drops off by 30-50%.
After calving, milk yield increases much more rapidly than intake capacity, resulting in a long period of under feeding.
Peak milk yield is reached in about six weeks after calving, peak appetite is not reached for about 12 weeks.
Even on good quality grazing, cows’ intake is only 10kg per day in the first week after calving, while it increases by 1kg/week for the following six or seven weeks.
Cows should therefore get some concentrates for at least the first six weeks of the lactation, in order to maintain adequate feed intake.
Low intake after calving can have a very serious effect on cows, especially if the forage quality is only average, or poor. Excessive weight loss between calving and breeding has been shown to be the major cause of infertility.
Cows losing less than 0.4 of a condition score between calving and first service have more than double the conception rate as those losing 0.5 or over of a condition score.
Feeding about 2 kg of a suitable concentrate to cows for a few weeks before calving can generally be recommended.
Some compounders have specific, properly balanced nuts, including pre-calving minerals and yeast, for this purpose. This concentrate helps to maintain intake in the run-up to calving, and conditions the rumen to allow much quicker introduction of concentrates after calving.
It also minimises health problems around and after calving.
Trials have shown that this concentrate does not increase calving problems with Friesian/Holstein type calves, provided cows don’t get too fat.
It may be somewhat different with first calvers, if they get too fat.
Programmes to have cows calving in ideal condition and properly prepared for the following season have been shown to have a significant effect in reducing losses after calving due to metabolic diseases.
It is widely accepted now that treatment of cows during the dry period and especially in the run-up to calving is vital to success for the remainder of the season.
Where cows are calving close to going to grass, there is less likelihood of problems.
Proper feeding and care during the dry period, in the two or three weeks before calving, and in the early lactation period, helps to increase the six-week calving rate to 90%, over a period of a few years.
This has been estimated by researchers to be worth up to €15,000 in a 100 cow herd.
Feeding after calving
While cows are indoors on 70 DMD silage, there will be an economic response to feeding 6-8 kgs of an 18% protein ration (24% with maize) per cow per day, peaking at 30 litres/6.5 gallons.
Add or subract 1kg for each five DMD units above or below 70.
With a few hours of good quality grazing and silage ad-lib, feed about 5 kgs.
When cows are out grazing by day, and at silage by night, concentrates can be reduced to 4 kgs, depending on grass quality.
When cows are outdoors fully, feed about 3kgs of a lower protein concentrates.
In practice, many farmers feed significantly above or below these levels.
Do not take chances with under-feeding cows, because this will have serious long- term effects.
Most of the concentrates should be front loaded in the early lactation period.
If some cows are losing too much condition, they could be put on once-a-day milking for a while.
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