Garth Braun, General Manager at Canadian Centre of Gene Transfer – Genesus Inc. 

One must consider the boar as a very important part of the farm’s reproduction success, so special attention is needed when it comes to boar management, considering nutrition, vaccinations and herd health programs. Also housing and the aggressiveness of the male may determine the amount a boar is being used.

Boars, like sows, must be treated with compassion and dignity, to maintain a positive and economic well-being for the animal and producer.

In house boars should be distanced from sows in estrus and should be in a clean (minimal organic matter)  hospitable environment with good ventilation, temperature and always have access to a  clean source of quality water.

Feeding program is based on whether the boar is used for artificial insemination or natural service. For example boars used for natural service the goal is to minimize body weight so they can be used to service gilts and smaller sows gilts but without compromising a healthy body condition.

Boar nutrition requirements are somehow similar to the dry sow specs – increased zinc and selenium levels; including calcium and phosphorus above grow finishing diet. Feed quality and nutrition program has a direct impact on sperm count and quality as well as boar stamina. Omega-3 fatty acids appear to have a positive influence on fertility but consult your nutritionist before adding to the boar’s diet. 

Sub-optimal reproductive performance may be due to deficiencies or excessive allowance of various nutrients. Distilled grains with mycotoxins should be avoided, as they will negatively impact  reproduction. Mycotoxins such as zearalenone , fusarium & aflatoxin B1 can severely affect         motility, membrane integrity, acrosome integrity and ability to fertilize. Additionally, zearalenone suppresses libido mimicking estrogen, initiating a wide variety of changes to the hormonal levels and patterns. 

Guidelines for boar activity tracking, seamen collection and evaluation

Boars, as most mammals, need to have a consistent routine, ex.:  being fed at the same time of day with ample clean drinking water and proper handling.

The recommended approach is to evaluate and track every boar individually. Keep a record of vaccination, health, semen quality and production of each boar. Treating every boar as an individual will help determine if the animal is to be used, treated or culled.

A boar will generally reach puberty between 6-8 months of age depending on breed and genetics. At this stage, it is recommended to use the boar once a week with A.I collection and a maximum of twice a week for natural service. Once the boar has been collected/serviced for the first time, repeat collections should be recurring no tater then the 7-10 recommended rest days. Once the boar has reached its 1st birthday, the collection process in most cases can be doubled with only 3 days rest between collections.

Semen production and semen quality is impacted by the boar’s environment, health and well-being. Boars under stress, caused by factors such as those discussed above, will impact semen quality.

Boars in good condition should have good libido when reaching puberty and produce a minimum of 30 billion cells per ejaculate. The colour of the ejaculate should be opaque to white with > 70% motile cells and normal morphology exceeding 75%. Boars with consistently low or marginal quality spermatozoa (motility and morphology) in a 3 months window are unlikely to ever improve.


Boars may have challenges throughout their lifetime that will affect semen quality. From toxins in the feed, health challenges, temperature range in the facility or stress from not being fed on time.

Not all animals can handle stress the same. It is important that as soon that we observe a low libido boar or have sperm quality related concerns, to address this issue as soon as possible and look back for records to determine a possible cause and rectify accordingly.

1.    Gary C. Althouse  Boar Management  MSD Manual Veterinary Manual
2.    Sylvia J. Bedford-Guaus Breeding Soundness of Boars
3.    W.L. Flowers  Semen Quality National Hog Farmer
4.    D’Mello JPF, Placinta CM and MacDonald AMC. Fusarium myctoxins. A review of global implications of animal health
5.    Reese D. Omega 3- fatty acids and swine reproduction

Categorised in: ,

This post was written by Genesus