Common Disorders of Breeding Rams

Moredun-logoSummary written by Professor Neil Sargison FRCVS and Matt Colston MRCVS

Taken from Moredun Foundation Newsheet Volume 5 No. 11 (2011)



  • ram-in-harnessGood nutrition & general health management are key to maintaining fertility in rams.
  • It is important that rams are in good body condition and free of disease for at least 2 months before mating during which time sperm production occurs. General illness or management issues that allow an increase in testicular temperature will also affect fertility.
  • The use of unsound rams generally reduces the lambing percentage and may result in a protracted lambing period. Breeding rams require normal genital organs, normal libido, the physical ability to mount and mate ewes and an adequate number of normal sperm in each ejaculate.
  • There are a number of diseases of the reproductive tract which can adversely affect ram fertility, sometimes permanently.
  • Rams should be checked for breeding soundness well in advance of the mating season to allow time for the purchase of replacements if necessary. In commercial flocks, rams are usually examined 6-8 weeks before the mating season, when they should be sexually active. Ram soundness investigations should include a relevant history of each ram, a full clinical examination, a thorough genital examination and if required, examination of a semen sample.
  • The basic requirements of breeding rams are that they can confer positive physical characteristics, however, rams also need to be free from physical defects and production-limiting diseases, immune to any important diseases which are endemic in the flock, and sound for breeding purposes.



sheep cover2 smMore information on ram selection and preparation can be found on the DVD 'The Breeding Flock' - programme 3 in the series 'Sheep on Your Smallholding'.








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