Even after the milk feeding period, good and undisturbed growth is necessary to achieve a well-developed heifer at the first calving. A well-developed heifer will produce more milk. Extending the rearing period to achieve this weight costs more. For this reason, any disturbance to the growth pattern is expensive, and is not advisable. Sprayfo supports the entire process from calf to heifer.
Grazing period
In the grazing period, especially after the summer and in autumn, a lot of growth can be lost due to poor grass quality, lung worm and gastro-intestinal infections. Nevertheless, it is important for the animal to undergo the grazing period, because it builds up a natural defence against worm infections.
The following points should be taken into consideration:
- calves must be aged around six months before they are allowed to graze for the first time
- ingestion of aftermath (second crop of grass after first hay crop has been taken)
- additional feeding of compound feeds and fodder
- the grazing area should be changed every two or three weeks
- 8 to 10 weeks of grazing is sufficient to build up immunity
- timely return to the pens
Preventive inoculations may also be given against lung worm.
Regular growth pattern
A regular growth pattern is of the utmost importance. It has been proven that an increase in the feeding rate compensates for no more than 25% of the growth lost. Moreover, additional energy will be used, and there is a big risk of fattening, including of the udder tissue. This has a negative influence on the milk period to come. Average growth per animal, per day, is shown in the table below. To avoid set backs in rearing, ration calculations after weaning are needed for various age ranges in young animals’ lives.
Growth per animal per day in different periods, minimum 50% HF blood
|
Period (month)
|
Growth (g per day)
|
Final weight (kg)
|
|
Birth weight
|
|
± 40
|
|
0 – 2
|
550 – 600
|
74 – 77
|
|
3 – 8
|
800 – 850
|
220 – 230
|
|
9 – 15
|
675 – 725
|
365 – 385
|
|
16 – 22
|
600 – 650
|
495 – 530
|
|
23 – 24
|
300 – 350
|
510 – 550
|
|
|
|
(weight after calving)
|
Growth controls
The best method to determine whether growth is on schedule is to weighing the animals at random.
If weighing causes problems, measuring the heart girth and / or crotch height can provide an adequate indication of growth rate.
The relation between heart girth / crotch height and age / weight is shown in below table.
Growth curves
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