Synchronisation is used readily in the pedigree sheep industry for earlier lambing and for artificial insemination, but it is also used readily for producing ewe's milk.

For Yorkshire sheep milk producer, Chris Heslop, Spofforth, synchronisation is key to breeding sheep out of season for a consistent supply of milk throughout the year.

He milks 600 Friesland and Lacaune cross ewes over a 12-month period supplying the co-operative sheep milk UK with 150,000 litres of milk a year.

He has three distinct lambing periods – December, April and July. To make it easier breeding ewes out of season and to tighten up the lambing period Mr Heslop synchronises ewes lambing in July and December. After discussion with his vet it is something he started doing in 2017 to reduce the pressure on labour.

Like the Poll Dorset breed, milk sheep do cycle throughout the year meaning they can get in lamb out of season.

This means:

  • 150 ewes are synchronised around July 5 for lambing in December.
  • Another 100 ewes are synchronised 17 days later.
  • 150 ewes are synchronised in February to lamb in July

About 15 tups are used across each breeding group and are in with the ewes for only three days keeping the lambing block tight.

Sheep are only synchronised after their first lambing with all ewe lambs allowed to cycle naturally.

Product choice

Traditionally, Mr Heslop has used sponges to synchronise ewes, but this year he used CIDR® Ovis in 60 of his July lambing flock. Manufactured by Zoetis, this “T” shaped progesterone device mimics the natural progesterone of the sheep allowing regulation of follicular development, oestrus and ovulation.

This means when the device is removed the drop in progesterone causes oestrus behaviour. The timed injection of equine chorionic gonadotrophin means the developed follicles will ovulate leading to tight synchronisation.

He has found sponges to be effective in the past, but says they are not the easiest product to use so was keen to try something else.

“CIDR Ovis was much nicer to use than a sponge. It was easier to insert and remove. It is something I would use again. The pregnancy rates were comparable to using a sponge.”

Last year he achieved a 70% pregnancy rate to first service when using CIDR Ovis, which is what he would achieve with a sponge or when breeding naturally out of season.

How to use

CIDR Ovis is inserted for 12 days. On the final day the device is removed and the hormone eCG is given on removal. The onset of oestrus occurs 1-2 days after removal of the insert at which point the tups are placed in with the ewes.

Careful attention needs to be paid to hygiene, with disinfecting between each ewe and using an anti-bacterial lubrication gel to avoid damaging the ewe’s reproductive tract. All equipment is sterilised prior to use.

Lambs are removed between 24-48hours and are reared on a powder formula. Most pure-bred females are kept as replacements. Males and any non-breeding females are reared intensively on a 15% protein diet and finished for Dawn Meats.

Farm facts

  • 400ha farm
  • 600 milking ewes as well as a commercial flock of 550 ewes
  • Ewes milked twice a day with milk sold to Sheep Milk UK
  • Breed own replacements
  • Males and non-breeding stock finished intensively for Dawn Meats