Lifecycle of a Cow

Cows are mammals, like humans and dogs and many other household pets. There are some similarities and some differences between cows and other mammals like us.

Life for a cow starts as a calf or baby cow. With a lot of intensive care the female calf is reared till it is able to cope on its own. This usually takes about 3 months. At this time the calf is weaned or removed from milk and allowed to graze with the older animals.

 

 

As the young female calf grows she is called a Heifer or an unmated female cow. From weaning, the heifer will take about 15 months to grow to a size at which she can be mated (approximately 360 Kg for a Holstein heifer).

Cows have the same gestation period (pregnancy time) as humans: 9 months. Therefore the pregnant heifer will normally have her first calf at an age of 27 months old and a weight of 500 Kg.

 

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Before the calf is born the cow’s body begins to prepare for its birth by producing milk in the udder. Soon after the calf is born it instinctively feels for the mother’s udder and suckles causing the release of milk from the udder. The first release milk or fresh milk is called colostrums and is different to the milk we drink from a bottle. Colostrums is a special milk containing lots of vitamins, minerals, protein and energy, which provide the calf with life-boost and a protection against disease.

Once the colostrums milk has been fed to the new born calf, normal milk will begin to be formed in the udder. The cow will than be milked by machine and the milk collected and stored prior to being sent to the factory for processing. Once a calf is born the cow will continue to give milk for about 300 days, which is termed the lactation period. On average a cow may produce 5000 litres per lactation period, which is an average of 17 litres per day. However, the amount of milk produced is not the same on every day, with more being produced at the start of lactation and less towards the end of lactation period.

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About 60 days after calving the cow will be mated again so that she will have a calf to initiate milk production in 9 months from mating or next lactation. This will mean she should be back milking 360 days or a year after she first had a calf.

When the cow is about 300 days in milk she may only be producing 5 – 10 litres per cow, at this point the cow is dried off and given a rest from milking for about 2 months before calving again and the cycle continues.