Farm manager Andrew Solomann said foetal ageing lambs at pregnancy scanning allowed him to feed budget according to how many were conceived in each cycle. Lambs can be weaned according to age, by identifying lambs conceived in the first and second cycles.
“You can also start docking two weeks early and set-stock the later ewes on harder country.”
AgResearch scientist David Stevens has worked closely with Parikanapa Station since Landcorp’s focus farm programme began four years ago.
Parikanapa is the North Island focus farm. Much of the work has focused on lamb growth rates from birth to weaning.
Stevens said foetal ageing was more expensive, but farmers could make good use of the information when planning for spring.
AgResearch scientist David Stevens says Landcorp’s goal is to be New Zealand’s best farmer, but there is no reason why other farmers can’t set themselves that same goal.
“The more we get into foetal ageing and understanding that, that’s where a lot of the gains are coming from in terms of increasing weaning weight and lamb growth to weaning.”
Parikanapa targets a minimum tupping weight of 60kg and average of 65kg for mixed-age ewes. Minimum two-tooth weights targeted are 58kg, or 62kg average.
Solomann said the two-tooths averaged 1kg above target this year.
“If our two-tooths are a little bit light, that’s where all our dries are coming from.”
Older ewes mated to a terminal sire begin lambing on August 20, allowing their lambs to move off-farm from late in November.
Parikanapa is phasing out five-year-olds, aiming for four-year-olds to be the oldest ewes mated.
Deaths were up to 10% in ewes lambing as six-year-olds and Solomann thought it might be easier to market a five-year-old cull ewe than those another year older.
Any ewe lambs under 37kg do not make the replacement flock. Average ewe lamb weight last May was 41kg, up from 35kg the previous year.
Target pasture covers for lambing are 1200kg DM/ha for single lambing ewes and 1400kg DM/ha for twins.
Stevens said more precise knowledge of weaning weights and their spread helped to meet lamb supply targets, which was much easier if 45% of lambs were ready for processing at weaning.
“If you want to enter into a long-term contract you have to be able to supply it,” Stevens said. “Without that sort of flexibility you’ll have a lot of trouble supplying a contract that’s going to be worth any money.”
The goals at the formation of the sheep focus group four years ago:
- MA ewes scanning: 170%-plus, long-term target 187%
- Two-tooths scanning: 168%-plus, long-term target 170%
- Lambing: consistently more than 140%
- Losses: Less than 18% from scanning to docking
- Know lamb growth rates over lifetime
- Mid/late lactation weight (growing at 300g/day)
- Post-weaning (120g/day)
- Lamb weaning weight of 30kg
- Minimum cover May 1: 2000kg DM/ha