Replacement options for flocks: breeding or buying

To maintain a healthy and productive flock, whether expanding or not, inevitably means you will need replacements each year.

For some farmers, buying in will be the preferred option while others choose to breed their own replacements and follow a closed flock policy.

Each route has its pros and cons, and the best route for individual farms will depend on the land and the system.

See also: How shearing lambs can improve growth and reduce labour

Rhidian Jones spoke through the options to consider in a recent Farming Connect webinar:

What are the options?

  1. Buying in F1 replacements (see stratified sheep system diagram below) as ewe lambs or shearlings – the more traditional option.
  2. Buying in F1 replacements but also keeping some F2 replacements. Keeping F2 replacements might reduce cost and improve conformation of the lambs when put to a terminal sire.
  3. If you have hill land and lowland, developing your own stratified system. This works by crossing hill ewes and longwool rams to breed an F1 ewe on the hill ground and then putting the F1 ewe to a terminal sire on the lowland. The proportion of different ewes in the system depends on the amount of hill and lowland pasture you have.
  4. Running a purebred flock and breeding replacements. Lots of farms are using these sorts of systems now or using two or more maternal breeds such as Lleyn, Aberfield or Highlander in rotation.
  5. Purchasing maternal breed replacements and crossing them all to easy-lambing tups. With this, you’re relying on the breeder to do the recording and have a good flock health status. It’s a nice simple system if you’re running 200-400 ewes and can find a regular source of replacements.

Questions to ask before deciding

  • What would the value of your breeding stock be? Could you sell surplus females or rams as breeding stock? There is always an opportunity to add value by doing this.
  • What is your current situation regarding flock health, labour and buildings? Is your set up working or do you need to make a change? If you’re on the cusp of making changes anyway, perhaps you need to move forward with an easier maintenance breed.
  • Are you also considering changing system? For example moving to later lambing at grass or outwintering at grass? This will affect which breeds will work best in your new system.
  • Do you have the resources – the land, skills, recording ability – to breed your own replacements?

Buying in versus homebred replacements


Buying in

Homebred replacements


Depends on relative market price for lambs and breeding ewes

Depends on relative market price for lambs and breeding ewes

Control of genetics



Resource requirements (land and labour)

Not required


Flock health status

Risk of bringing in infectious disease and “iceberg” diseases unless coming from clean source farms

Reduced risk of infectious disease with a closed flock policy

Source: RJ Livestock Systems

Two key factors to consider if you decide on buying in

Age of replacements
Decide on whether you should buy ewe lambs or shearlings. Shearlings cost more, but can be put to the ram straight away.

You can also breed from ewe lambs straight away, but need to be sure they reach the necessary weight before tupping (60% of mature weight).

Normally, when you tup ewe lambs, you’d expect to get around 20% empty, so one option is to keep 20% more than you need. Those that don’t get in- lamb can be sold in the rising market in February/March time and you’re automatically left with the most fertile stock.

Our guide on breeding from ewe lambs explains the considerations for lambing young ewes.

Health status
Ideally, source directly from farms of known health status (iceberg diseases and vaccination status) that are using performance-recorded rams, or from a farm that you know the disease history of.

If buying from breed society sales, buy from flocks of known health status.

This article explains how to identify, prevent and treat the five sheep ‘iceberg diseases’.

Bought-in breeding stock should be vaccinated for infectious abortion.

Tips for breeding your own replacements:

First, you need to consider whether you start with what you have or replace the whole flock.

This will depend on economics – you’re probably selling your flock at a disadvantage and paying over the odds for new stock, so it might have to be a more gradual process.

If you are substituting your current breed for another one, it’s probably going to cost a lot of money. And bear in mind that your foundation stock is someone else’s second best, although there is more choice available now.

Once that is decided, here are some other things to consider:

  • Adopt a lambing score to select replacements as early as possible (see lambing score card below). The higher the score the better.
  • Make use of EID and software where possible to record traits.
  • Use performance-recorded tups with good maternal estimated breeding values (EBVs).
  • Split your flock into two groups – an A flock to breed replacements from and a B flock to put to the terminal sire.
  • Use older sheep – that have had a couple of lamb crops and no handling other than routine treatments – to breed from. These animals have shown they are well suited to the system on the farm.
  • Tag or ear notch ewes giving problems. You can make a lot more progress quickly through culling for certain traits rather than selecting for certain traits.

For more detail on what to look for in a breeding ewe, consult our full guide on selecting flock replacements.

Lambing score card





Lambing Ease


Minor help

No assistance

Mothering ability

Leaves lambs

Stands well back

Follows whatever

Lamb vigour

Has to be sucked

Slow to suck

Up and sucks

Note: Example only. Individual systems may need to adjust thresholds when getting more selective. Source: RJ Livestock Systems