Mating Ewe Lambs

This year will probably see an increased interest in mating ewe lambs due to the high cost of breeding hoggets, as a result of the unprecedented sheep meat prices. Michael Gottstein, Teagasc Head of Sheep discusses steps sheep farmers should remember when considering whether or not to mate ewe lambs

So what are the few steps that sheep farmers should remember when considering whether or not to mate ewe lambs?

Size

Size is king when it comes to mating ewe lambs. The success or failure of the endeavour hinges on ewe lambs being at least 60% of their target mature weight at mating time. For most lowland breeds this means having ewe lambs at least 45kg (60% of 75kg) at mating time. Ewe lambs that have not achieved a target liveweight of 60% of their mature weight should not be mated.

Abortion vaccination

Ewe lambs are very susceptible to toxoplasmosis as they may not have come in contact with the pathogen prior to mating and hence will not have had the chance to develop any natural immunity. Consequently vaccination at least one month prior to mating should be considered – talk to your vet.

Labour

In general most farmers will aim to lamb the ewe lamb flock after most of the main flock has lambed. This reduces the intensity of the lambing when the main flock is lambing but may prolong the overall lambing period. Ewe lambs that are lambing down for the first time need extra supervision, are more prone to lambing difficulty and issues such as mis-mothering due to lack of experience. Consequently high levels of supervision and intervention when required are critical.

Continual growth

Ensure that pregnant ewe lambs are on a feeding regime that allows them to continue growing not only through pregnancy but also during lactation. This will require running them as a separate group both during mating, pregnancy and their subsequent lactation so that they do not have to compete with the mature ewes. If the facilities to run the ewe lambs as a separate group are not available then they should not be mated.

Preparation for mating

Ewe lambs destined for breeding should be kept out of sight, sound and smell of all male sheep for at least six weeks prior to mating. . Introducing a teaser ram to stimulate ewe lambs to start the oestrus cycle two weeks before mating proper is due to begin will help to synchronise the mating period.

Mating

From a practical point of view fertile rams should be introduced to the ewe lambs two to three weeks after the main flock has commenced mating. The duration of the mating period for the ewe lambs should be no longer than three to four weeks so that  lambing is not prolonged.  Rams being used for mating ewe lambs should be selected for ease of lambing. Applying raddle to the rams is important to help identify what ewe lambs have been mated, projected lambing date and when pre-lambing concentrate supplementation needs to be ramped up.

Summary

Mating ewe lambs has the potential to increase life time output and increase farm profit. It does however require extra management and inputs to ensure that ewe lambs are not stunted (if under-fed) or have very difficult lambing’s (if over-fed) both of which will have a negative impact on their reproductive performance in following years.   

If you liked this article you might also like to read Ram Factors for the Breeding Season

The Teagasc Sheep Specialists issue an article on a topic of interest to sheep farmers every second Tuesday here on Teagasc Daily.  Find more on Teagasc Sheep here.