Annual MOT and semen testing of your breeding rams each year will ensure that potential sub fertile rams are identified and either not used of given a smaller group of ewes to mate.
It is essential to perform pre-breeding health checks on any breeding rams (including newly purchased and proven) to be used in the forthcoming season, as 10% of rams will have poor fertility. By running sub-fertile rams, overall flock profitability will be significantly reduced due to a lower lambing percentage, a higher number of barren ewes and an extended lambing period. Pre-breeding examinations should be carried out ten weeks before mating to allow time for replacements to be sourced and/or adequate time for any conditions to be treated. Remember also to consider screening for iceberg diseases, such a MV, CLA and border disease, in your rams, especially if new to the flock.
The pre-breeding health check consists of a ram physical exam followed by semen analysis. Firstly, a vet will carry out the physical exam paying particular attention to the ram’s testes, feet, teeth, BCS and treatment. A semen sample will be then be obtained via electroejaculation. The sample will then be analysed under a microscope while it is still fresh to look at how well the sperm move and the number of live and dead sperm. The individual sperm are then looked under higher magnification to see if there are any defects that would render the sperm unable to fertilise the ewes’ eggs. We can issue each ram tested with a pre-breeding examination certificate; the ram will be “passed” if he has no physical abnormality that would prevent him being able to naturally serve ewes and if his semen is of good quality. The pre-breeding exam is a good predictor for the current fertility of the ram. It does not however guarantee a ram’s fertility, but it does reduce the risk of unsuitable rams being used for breeding.