Sourcing replacement ewes
September 29, 2024
Within the sheep enterprise, replacements will be required to maintain a healthy and productive flock. To source replacement ewes, some flock keepers will choose to breed their own replacements and keep a closed flock. However, many opt to purchase replacements. This allows them to run a simpler system in terms of ram management.
On average, flocks replace 20–25% of their ewes every year, depending on their culling policy and ewe mortality. In this article College of Agriculture, Food and Rural Enterprise (CAFRE) Beef and Sheep Adviser, Rachel Megarrell suggests that now is the time to consider your replacement strategy ahead of breeding time.
Rachel highlights several points to consider when sourcing the replacement ewe.
Firstly, consider if you want to focus on the maternal aspects of the flock. This means, aiming for more prolific and milky mothers producing lively lambs; with females being produced that are suitable to be retained or sold for breeding. Alternatively, if the system in place is solely the production of lambs for slaughter, then the attention will be on terminal aspects, aiming for size, conformation and growth.
Next, and in a similar fashion to assessing and selecting ewes for culling, follow the rule of the three Ts, toes, teeth and teats for selecting replacements. The jaw should be neither overshot or undershot. You want ewes with good mobility and sound feet. They should show no signs of lameness or misshapen hooves. This could indicate an underlying issue with infectious diseases, such as foot rot. Make sure that you carry out an assessment of the udder and teats, checking for any lumps or swelling. Finally, an assessment of body condition and conformation should be made.
It is important that all the above checks are made prior to purchase. In the interest of health and performance it is advisable to buy from a recognised source. Otherwise, you may well be buying in problems.
Purchasing flock replacements is less time consuming and requires less complex recording. However, one of the main disadvantages is the risk to flock biosecurity. This risk can be managed through good animal husbandry procedures being employed on arrival of newly purchased animals.
To maintain a healthy flock status, a robust quarantine system must be in place. It is imperative to keep new animals quarantined for at least three weeks. Also, you should allow them to graze on fields that have been previously grazed by your own stock. Prior to this, if possible, yard all sheep for 24-48 hours. Treat for worms and fluke as soon as is reasonably practical after purchase. You should also administer any necessary vaccines to cover infectious abortion and clostridial diseases.
In relation to worm control, best practice is to use a Group 4 wormer. Observing the quarantine period will also allow time to observe for signs of scab. Some of the clinical signs include severe itching, scratching and a visible loss of wool. While lameness and mobility can be observed physically, it is worth asking if a foot rot vaccine has been administered and a footbath on arrival should be non-negotiable.
By addressing all the above in terms of animal health and ensuring that replacements are introduced onto the farm in a timely manner will give the flock the best possible chance of having a productive breeding season which will increase flock profitability.
Whole flock management can be discussed further with your local CAFRE Beef and Sheep Adviser.