Story: Beef farming

Page 6. Beef breeding

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Essential role of cattle on hill country

Breeding-cow herds are usually located in high country and on hard and medium hill country. They are complementary to sheep, maintaining and improving pasture quality by stopping it becoming too long and rank, and grazing poor-quality pasture where sheep would not thrive.

Cattle also ‘clean up’ pasture by eating the larvae and eggs of internal parasites that infect sheep, but do not harm cattle. On New Zealand hill country, farms that stock both sheep and cattle are usually more productive than those with just one or the other.

Turning a profit

Beef cattle require much less time and labour to tend than sheep, so they cost less to run.

The income from breeding cow herds is from the sale of surplus calves. So farmers aim to:

  • rear a large number of calves, ideally 95 calves for every 100 cows mated
  • ensure they are as heavy as possible, preferably 230 kilograms or more, to make them attractive to buyers.

Pasture preferences

Cattle and sheep have different grazing patterns, and do not compete for the same feed. Sheep nip pasture plants between their incisor teeth and the dental pad on their upper jaw. They prefer pasture that is short and not too coarse. Cattle graze by wrapping their tongues around foliage and tearing it off. They prefer long pasture, and can thrive on rank feed that sheep would not eat.

There is also some return from old or unproductive cows that are sent for slaughter. Farmers on easier country may also finish (get in prime condition for slaughter) some of the calves that they rear.

The main breeds in beef breeding herds are Angus, Hereford and Angus–Hereford crosses. In large breeding-cow herds, another breed of bull – such as a Simmental or Limousin – might be mated with older cows, which can produce heavy calves that return a premium when sold.

The seasonal round


The seasonal round begins in early spring with calving. Normally the cows are stocked in blocks or paddocks and left to get on with the job. Sometimes a farmer puts young cows having their first calves in more accessible paddocks in case they need help. Calving lasts six weeks.


A freemartin is an infertile female calf born as a twin with a male calf. For beef cattle, usually less than 1% of births are twins. In about 90% of twin births, the twins are male and female. The transfer of blood and hormones between the calves during pregnancy often affects the development of the female’s reproductive tract, so she is born infertile.

Soon after, the animals are mustered into the cattle yards. The calves are separated from the cows and forced into a narrow race for marking. Bull calves are usually castrated using a rubber ring which restricts the flow of blood, so that in time the testicles and scrotum wither and fall off. All the calves are given an earmark which identifies them as belonging to a particular farm or station. Finally a pour-on treatment, which kills both internal and external parasites, is applied to their backs.

The cows are also treated against parasites before being reunited with their calves. The calving percentage (number of calves born per 100 cows) ranges from around 80% on hard hill country to over 90% on easier hills.


A cow’s gestation period (the time from mating to calving) is about 40 weeks. Farmers decide when they want their cows to calve and put the bulls with them to suit. The oestrus cycle of cows is 21 days, so the bulls are left with them for six weeks, ensuring that each cow will be fertile at least once during that time and have the chance to mate. A tight calving period ensures the calves are even in size at sale time, making them more attractive to buyers.

Massive Molesworth

Molesworth Station, in the Marlborough high country, is the biggest farming property in New Zealand, covering 180,476 hectares. It is run as a cattle station, with 10,000 cattle, including 3,500 breeding cows. In autumn, 6,000 cattle are mustered in a single mob.


In autumn, when they are seven or eight months old, calves are weaned off their mothers at the time of the local calf sales. The day before the sale the cows and calves are mustered into the cattle yards and the calves are separated from their mothers.

The best heifer calves are kept to become replacement breeding cows. Often they are all kept, and the selection process is made after the next winter.

Steer calves are sorted for sale according to their size. If the herd is cross-bred, they are also sorted for coat colour so that the lines look attractive to buyers.

Early the next morning, often before daylight, the calves are loaded onto stock trucks and taken to the saleyards, where they are auctioned to farmers who will fatten them for slaughter, for export or the local trade.

How to cite this page:

Robert Peden, 'Beef farming - Beef breeding', Te Ara - the Encyclopedia of New Zealand, (accessed 23 May 2024)

Story by Robert Peden, published 24 Nov 2008