Increasing numbers of sheep producers are following in the footsteps of their dairy counterparts by using artificial insemination (AI) as a means of improving genetic traits in their flocks.
First generation farmer Simon Kavanagh, who keeps 700 pedigree Lleyn ewes and 500 gimmer lambs at West Berwick Farm in Draughton, near Skipton, is among those taking advantage of the benefits of this breeding tool.
Mr Kavanagh, who has been doing work with AI in his flock for the past ten years, says the benefits of AI include more rapid genetic gain, the ability to use the semen from top-quality tups, which you might not have been able to buy, and the ability to spread a ram across a larger number of ewes.
"My main objective is to produce top-quality replacement breeding stock for farmers," says Mr Kavanagh, who sells a large proportion of breeding stock to producers up and down the country.
"Although AI is relatively expensive, I do it because of the rapid genetic gain I get, and I can spread one ram over many ewes. I have always been very pleased with the results - you get a very even batch of sheep."
And this move towards artificial insemination was born out of the foot-and-mouth disease outbreak in 2002, when Mr Kavanagh was unable to buy a tup due to movement restrictions, and AI was the only option, once special permission was granted to move fresh semen between two counties.
How it works
"All the lambs are done in a week - the best 300 are artificially inseminated. A specialist vet team - Innovis - comes down to the farm and they collect the semen and do it all," says Mr Kavanagh.
"We insert sponges into all the ewes, which synchronises them, and they are then taken out 12-14 days later. The ewes are then injected with PMSG (pregnant mates' serum gonadotropin) and 36 hours later they are artificially inseminated. You can use frozen semen, but fresh semen is better for a high conception rate of about 85%."
The process, also referred to as laparoscopic (minimally intrusive) AI, requires the ewes to be sedated and put in a crate upside down, before the AI procedure is carried out by the specialist vet team. This is done via the stomach of the sheep, as they have tight cervixes, adds Mr Kavanagh.
Any sheep which don't hold to the AI service come back on heat again 17 days later, and are put with a sweeper tup to ensure they get in-lamb.
Mr Kavanagh adds: "It could cost up to £15 a ewe to do, which is ok for what I'm doing, but if you are just producing commercial fat lambs it might be more difficult to justify the costs involved."
A typical 14-day AI programme
Day 1: Insert sponges
Day 12Remove sponges and inject PMSG at time specified
Day 13: Starve from noon
Day 14: Artificial insemination at times specified on programme
(Information provided by Innovis)
|Sheep AI facts |
- Allows farmers to spread one ram across more ewes than would normally be possible through natural tupping
- Through the use of frozen semen, farmers have access to rams they wouldn’t normally be able to buy
- Allows farmers to share rams
- Disease risk is minimised through not having to buy rams
- Ensures a more compact lambing period, saving on labour
- Typical conception rates for fresh semen are 75-95% and for frozen semen 60-70%
- Organic farmers can synchronise their sheep using teasers, rather than intra-vaginal sponges
- Procedure costs up to £15 a ewe