Farm systems scientist Tom Fraser says management in the four to six weeks prior to lambing and the two to three weeks after can affect lamb survival, weaning weights and profitability for the season.
“Kilograms of lamb weaned per hectare is still the biggest driver of profitability in our sheep systems.”
He says most people are happy with their scanning percentages but unhappy with their weaning weights and this comes down to understanding the nutritional requirements of their ewes.
He says today’s genetics means most ewes are capable of growing twin lambs at 300gms/day throughout lactation and weaning 34-35kg lambs, it is matter of growing and managing feed and feeding to achieve target intakes and body condition to allow the sheep to realise their potential.
Many areas have enjoyed a good “growthy” year and a reasonably kind winter, so Tom says most farmers will be going into spring with plenty of feed.
It was now a matter of managing that feed to retain both quality and quantity.
He predicts it will be another good season for subterranean clover in many hill country areas and using cattle to clean up longer grasses now will allow this high-quality legume to flourish in early spring and drive lactation and lamb growth rates.
Some areas, such as Nelson and Marlborough, had a particularly growthy summer and autumn and farmers in these regions may have gone into winter with high pasture covers and not enough stock to clean them up.
Tom says this could impact on pasture quality in spring where swards may contain a lot of dead material. This will impact on lamb growth rates.
In areas where feed is short, urea can be a valuable tool to boost pasture growth going into spring.
“It’s a no brainer, even sunny faces on hill country will respond to urea in August.”
While farmers always need to be mindful of nitrogen leaching, Fraser says research carried out by AgResearch has shown that environmentally, a small application of 30kg nitrogen/ha will actually reduce greenhouse gases and nitrogen losses by growing lambs faster. This means the lambs are finished and off the farm a lot quicker making for a much more efficient system.
Banks Peninsula farmers Hamish and Annabel Craw are getting ready to set-stock their ewes for lambing on pasture covers of over 1200kg DM/ha.
This pasture height will ensure the legumes in the sward get enough light which will allow them to flourish.
The couple, who are Beef + Lamb New Zealand Innovation Farmers, have had to work at maintaining pasture quality going into spring this year.
Following a growthy summer, Hamish says they went into autumn with too much rank feed and have subsequently used ewes and cattle to chew this down and open up the sward. Extra trade lambs were carried through and finished on surplus high-quality pasture.
Going into lambing in early August, Hamish says they are pleased with both their pasture quality and stock condition.
Hamish and Annabel are particularly focused on utilising legumes in their pastures to drive ewe lactation and lamb growth rates.
Their Innovation Farm project was to grow an additional three tonne of drymatter per hectare on uncultivable hill country by increasing the legume content of the sward to 40 per cent.
They have achieved this goal on trial blocks by using a mixture of agrichemicals and management. A field day summarising the results of the four-year programme will be held on their farm in November.