AbacusBio consultant Jack Cocks said taking steps such as putting more ewes to terminal sires, looking carefully at ewe replacement rates and realising that ewes had a shorter lifetime, could help a farmer's bottom line.
Using terminal sires over a greater number of ewes did impact on selection for replacements, culling of ewes and flock genetics and lambing, but a terminal sire lamb was worth $2.50 a head more than a maternal breed lamb through faster growth rates, weight of meat grown and lamb survival.
At $2.50 extra a lamb over 2100 lambs from a flock of 3000 ewes producing 150% lambing, that was an extra $5250 or $1.40 a stock unit.
"A lot of farmers potentially did not put as many ewes to a terminal sire as they could to capture those benefits," he said.
High ewe death rates also meant farmers had to carry more ewe hoggets which could be costly, but this was also sign that ewes were not lasting as long.
Research in Hawkes Bay showed there was merit in preferentially feeding single lambs so greater numbers could be quit at weaning.
"Singles have the greatest potential to grow faster," he said in an interview.
He also urged farmers to think about valuing the longevity in ewes, the impact of high replacement rates, why ewes were dying and the genetic influence in flocks of repeat single lambs.
There was highly repeatable and anecdotal evidence of genetic repetition of wet dry ewes, poor mothers and tail-end ewes.
Many sheep farmers were looking at dairy support as a wayof improving cashflow and viability, but Mr Cocks said it wasnot all plain sailing.
Dairy heifer grazing rates from calf to April 30 were between $4 and $5 a head a week, from May to the end of April $6.50 to $8 a head a week, for the month of May $18 a week plus potential weight gain bonuses.
But, Mr Cocks said dairy heifers were inflexible, and to satisfy owners' requirements meant a constant supply of high quality feed, including during autumn when grass growth was slowing and sheep farmers were looking for pasture to finish lambs and flush ewes.
Winter grazing cows can earn between $23 a head a week and $30, or from 27c to 35c per kg of dry matter a week,Selling crop for winter grazing can be worth 25c to 30c kg dry matter but he said there were issues to consider such as sustainability, crop utilisation and yield and the need for supplements.
He said farmers needed to think whether the soil could handle a winter of intensive-grazing by cows, the impact of severe pugging on future crop production where dry matter production could fall by up to 40% and cereal yields by 28% to 36%.
Another factor was the need to rotate crops and whether there was sufficient area for that.
Resowing a brassica crop too soon could lead to disease risk.
There were also issues of nutrient leaching and run-off.
The cost of growing kale was $1000 a ha compared to $600 a ha a few years ago, but Mr Cocks said skimping on inputs was not an option if there was a contract to winter a certain number of cows.
A 12 tonne a ha of swedes cost 18c a kg dry matter (c/kg/DM) and a similar yielding crop of kale 14c/kg.
DMSupplements needed for a balanced diet were also costly.
Baleage which yielded 200kg DM per bale, cost $60 a bale, or 30c/kg/DM when waste and opportunity cost of the feed was added.
Straw yielded 250kg DM per bale or up to 20c kg DM.
Selling standing grass for dairying was worth 15c to 23c a kg of dry matter and the cost of the loss of nutrients was worth about $24 a bale of baleage.
Growing crops was another alternative being looked at, but Mr Cocks said farmers needed advice and equipment, as a generation of farmers no longer had that knowledge or machinery.
But there are implications from cropping, including removing the best lamb finishing country, potential impact on soil structure, lower stocking rates and there could be extra pressure on ewes at mating time.