Quality Dohne Rams Improve Growth & Fertility at Esk Farm

RICHARD & SARAH JOHNSTON
ESK FARM, TASMANIA

THE dual-purpose attributes of the Dohne breed have given Tasmanian mixed farmers Richard and Sarah Johnston increased market flexibility, with their annual draft of crossbred lambs in strong demand from processors.

The Johnston family take care of a 460-hectare property, Esk Farm, near Longford, running 2000 Merino and Dohne/Merino-cross ewes.

They also grow a range of crops for both fodder and seed, including peas, grass seed, clover, chicory, lucerne, wheat and barley and lucerne and grass hay production and run a contract spraying business.

Traditional wool growers, the Johnstons decided to introduce Dohnes to their operation more than 10 years ago and continue to be pleased with the breed’s wool quality, fertility and growth.

They currently run 1000 Merino and Dohne/Merino-cross ewes joined to Dohne rams for replacements, along with 1000 Dohne/Merino-cross ewes which are joined to Poll Dorset
and Southdown rams. The flock micron average is 18.5.

“Dohnes have given us the flexibility to keep our ewe numbers up and expand the marketing options for the wether lamb portion as their growth rates are better than straight Merinos,” Mr Johnston said.

“We’ve been able to value-add our wether lambs and because the Dohne is a bigger framed sheep it has also given us the ability to use Poll Dorsets, allowing us to get the lambs out the door quicker.

“The breed’s maternal attributes of fertility, ease of lambing and mothering ability have also helped to increase our lambing percentages from an average of 85 per cent up to just over 100pc.”

“We are still getting something from their wool too, we shear the Dohne/Merino lambs in June and they average about 17 micron at eight months of age, while the Poll Dorset-cross lambs wool averages 21 micron.”

Mr Johnston has been sourcing his Dohne rams with selection focused on structural soundness, micron, wool quality and performance measurements.

“I use Australian Sheep Breeding Values to select rams with a low birth weight and good post weaning weight so I know they get up and get going quickly and they have to be positive for fat depth to improve lamb survival,” Mr Johnston said.

“I am also aiming for a finer-style crimp in the wool and we don’t want them over 19 micron.”

All the ewes are joined for six weeks from April and start lambing in mid-September. Pregnancy scanning is carried out in July to identify single and multiple-bearing ewes and early
and late lambers which helps with ease of management.

Making a change to Dohne/Merino-cross ewes has significantly improved flock fertility with lamb marking rates increasing by more than 15 per cent.

This year’s scanning rate averaged 145pc and Mr Johnston is confident lamb marking rates will be about 105pc. The twin-bearing ewes are separated at scanning so they can be given preferential treatment, generally grazing the high quality wheat and grass seed crops.

“I keep an eye on their condition score, normally we would feed out about 40 tonnes of wheat or barley in the lead-up to lambing as winter is the tightest time for us,” he said.

“But this year the condition of the sheep has been excellent.”

The single and twin-bearing ewes are then mixed together in mob sizes of 100 to 250 head and set stocked for lambing.

“In the past I’ve found if we just have a designated twin mob too many lambs are mis-mothered, so now we work on the number of lambs on the ground,” Mr Johnston said.

“Generally we aim to have the ewes in mobs of 100 to 250 single and twinners, but this depends on the paddock size and pasture assessment before lambing.”

The Johnstons aim to turn the crossbred lambs off at a target dressed weight of 22 to 24 kilograms. They are sold over the hooks with the majority going to MC Herd in Geelong.

“I leave the top 200 crossbred lambs in the wool and start selling them from early April onwards, while the balance will be shorn in February,” Mr Johnston said.

“They will be weighed every three to four weeks and as soon as they hit 46kg liveweight they are sold.”

The top draft of the Dohne wether lamb portion is also sold over the hooks at 22 to 24kg, while the remainder will be marketed to Tasmanian Quality Meats, Cressy, in their 12 to 20kg dressed weight light lamb category.

“We don’t sell the wether lambs any earlier as we need mouths from this time of year onwards through the summer to keep on top of the grass seed crops,” Mr Johnston said.

”We aim to have all the lambs sold before they hit 12 months of age. Our best money for lambs is when the mainland runs out so we want all our crossbred lambs sold by July before the new season lambs hit the market.”

The replacement Dohne/Merino-cross ewe lambs are grown out on quality pastures and classed on frame size, wool quality and structure before joining.

“I do a three-way class, the bigger-framed ewe lambs with good quality wool will be joined to the Dohnes, the plainer-wool big ewes are mated to Poll Dorsets and the smaller ewes will go to Southdowns,” he said.

Some of Richard and Sarah Johnston’s Dohne/Merino-cross ewes with Poll Dorset-cross lambs at foot on their property Esk Farm, Longford. The crossbred lambs will be sold over
he hooks at a dressed weight of 22 to 24 kilograms.

Original article written by Kylie Nicholls, Stock & Land, October 2020