Failure of the boar to show sexual interest and activity is common in maiden boars. Some times up to 30% of animals may be affected. Some pig farmers insist that any boar they purchase has been libido checked at least once before he arrives on the farm and some breeding organisations carry this out. It is performed either by the boar mounting a gilt in heat or encouraging the use of a dummy. In spite of this occasionally such tested boars will not work on the farm and careful coaxing and patience are required.

Now that breeding companies are tending to sell synthetic hybrid boars rather than pure bred boars libido problems should diminish.

Procedures for libido testing

• Provide a well bedded pen with a non-slip floor.
• Boars should be a minimum of 6 months old.
• Make good empathy with the boar.
• Be patient and show no aggression.
• Test boars in the morning when it is cool.
• Use a gilt firmly on heat. Always introduce the gilt to the boar pen.
• If no gilt is available use an AI stool.
• Spray the stool with urine from a sow on heat.
• If there are poor responses:
  • - Move the boars to different pens. - Have the boars within sight of a service pen.
    - Mix with a sow on heat.
    - Leave a dummy stool in the pen.
    - Inject with prostaglandin.
    
• Cull boars if there is no response after six weeks.

Factors and actions to consider if a boar lacks libido

• Age of the boar. Has he reached puberty?
• Breeding. Are there any hereditary problems?
• Has the boar normal testicles?
• Is he housed in a poor social environment with little contact with other pigs?
• Boars reared in a total male environment can become infertile.
• Give plenty of female exposure.
• Is the boar apprehensive?
• Is he a timid or bullied boar? Has he been bullied by sows?
• Poor stockmanship.
• Boars reared on slats in intensive conditions have poor libido.
• Is empathy with the pig poor?.
• Are lighting patterns poor? Ensure 14 hours of light per day.
• House the problem boar next to a mature good working boar.
• Allow saliva contact with working boars.
• Assess the response to an injection of prostaglandin or luteinising hormone but do not be too hopeful.
• Check for mouldy feeds (zearalenone toxin).
• Check for a damaged or defective penis. Sedate with azaperone (Stresnil) and examine.
• Provide a dry, well bedded, well drained pen.

Disease

• - Look for any sign of respiratory disease, mange or sloppy faeces, pain or lameness.
  - Check for parasite burdens.
  - Lameness in particular, leg weakness or arthritis.
  - Inappetence.
  - A history of influenza or PRRS.
  - A previous history of pneumonia or rhinitis.