Short gestation genetics breakthrough
A major breakthrough in shortening gestation length – the gap between conception and birth – has occurred in the dairy
industry this spring.
In South Canterbury, a surprise delivery saw separate Hereford calves born 30 days earlier than is normally the case in
dairy cows. Both in good health, and with normal birth weights.
Farm improvement co-operative LIC, which supplies around three-quarters of the country’s bull semen, has been working to
breed bulls with a shorter gestation interval of their resulting offspring.
Shortening gestation length is at the forefront of dairy genetics, as a way to help farmers bring late calving cows
forward, and get more ‘days in milk’. Revenue implications are in the tens-of-millions for the industry from the
increased productivity.
Malcolm Ellis, LIC’s short gestation breeding programme manager, says the early birth of the Hereford calves is “by far
the biggest achievement” since the co-op began researching short gestation 15 years ago.
“Hearing that these calves were running around the paddock 30 days early was like music to my ears,” he said.
“With the standard gestation length of dairy cows being 282 days, these calves will make a significant impact on
programme going forward, and the options we provide our farmers to shorten gestation length of their cows.
“Their potential contribution to milking days in the national herd is huge. Every farmer knows there is a lot more money
in a milking cow than having to graze a dry one, and, as the industry moves toward zero tolerance of inductions, short
gestation genetics will provide a very powerful tool to bring those late cows in line with the rest of the herd – in a
sustainable way.”
The calves – a heifer and a bull – were bred with embryo transfer technology, using top Hereford cattle in partnership
with Shrimpton’s Hill at Cave, South Canterbury.
Seeing them so early was like finding out you’d won the lottery, Shrimpton’s John McKercher said.
“We were blown away to find calves in the paddock, a whole month early. It’s certainly the highlight of 26 years
breeding Herefords.”
Ellis said the early-born calves have sought-after gestation genes, which is highly-heritable to future offspring.
“Being born 30 days early gives these calves a gestation length breeding value (BV) of -14. This means that when the
bull calf is mated to a typical dairy cow, it will create a Hereford-cross calf that will be born seven days early,” he
said
“Multiply those seven days across a mob of late cows, on farms all over the country, and it absolutely blows my mind to
think how many days of milk these calves could deliver to the industry.”
LIC has a number of short gestation options that farmers are utilising at the end of their AB mating period this spring,
currently offering between five and 10 days earlier calving on-farm. These calves will contribute to the co-op’s
Hereford and combination-marker options, which deliver offspring with a white or mottled face, making them easy to
identify in the paddock.
Semen from the bull calf born at South Canterbury will start to be collected by LIC next year, while the heifer calf
will become a donor for embryo transfers.
ENDS