Tup Vasectomies – It’s Teaser Time

Now is the time to start preparing for the upcoming breeding season, which includes planning tup vasectomies. Teaser tups (a vasectomised tup that although may still produce sperm, cannot ejaculate it) are a useful tool in flock management, helping to improve breeding performance and achieve a more compact lambing.  

Tups chosen to be teasers should ideally be homebred (to avoid the risk of introducing disease to the flock) fit, healthy and well-conditioned, with good feet and good teeth, and no history of disease. Usually, the tup chosen will be either a lamb or shearling. Planning is important as tups need to be vasectomised well in advance of the breeding season ideally 6-8 weeks before they are needed, to allow the wound to heal and for any viable sperm to leave the body. After being vasectomised, your tup will still have testicles and behave like an entire tup but will not be fertile. The surgical procedure must be carried out by a vet.  

The teaser is used in a flock to encourage ewes to begin oestrous (cycling) in advance of the start of breeding. For the teaser to be used correctly ewes must be separated from the sight and smell of tups for at least a month, before the teaser is introduced to achieve maximum results dubbed ‘The Ram Effect’.  

The ewes will react to the teaser by ovulating, with a normal 17-day cycle following. The teaser should stay amongst the ewes for 14 days, before being removed, with the fertile stock tups introduced immediately.    

Speak to your practice vet if you are considering using a teaser tup this season.