The extender reconstitution process is a fundamental step in the preparation of swine semen doses, prior to the insemination process. Performing it correctly has a direct impact on the quality of the seminal doses, and for it to be successful it is necessary to take into account a series of factors:

Choice of extender

Extender plays a very important role in semen preservation and a diluent must be chosen to protect the sperm from critical challenges that can compromise semen quality.

In order to choose the most suitable extender, we must not only consider the days of conservation, but also its capacity to preserve the semen under ideal conditions.

Importance of water

The water used in the production of seminal doses must meet minimum requirements set by the standards of various organizations such as ASTM, CAP, NCCLS or ISO. Water that meets the minimum requirements is called Type II water and can be obtained by various treatments, always taking into account the quality of the initial water.

One of the mistakes we can make is to use only the pH criterion to assess the quality of the water in our laboratory. Therefore, the best parameter to evaluate the laboratory water of a swine artificial insemination center is conductivity or resistivity.

Reference parameters for water suitable for production of doses:

  • pH: 5-8
  • Calcium hardness: < 3 mg CaCo3/litre
  • Conductivity (Conductivity: < 5 µsiemens/cm)
  • Absence of microorganisms (bacteria/ molds and yeasts)

Steps to follow

  1. Heat the water to the desired temperature (depending on the form of work, normally 37º).
  2. Pour the diluent in the proportions indicated by the diluent.
  3. Shake until complete dilution.

Checking the dilution

Osmolality is a very important value to evaluate the correct reconstitution of the diluents. The refractometric index, measured in brix degrees, correlates with the osmolality.

The refractometer is an economical, fast and easy-to-use device. It is a perfect tool to check the correct reconstitution of the diluent in situ at the boar stud before use.

By taking these factors into account, the dilution process can be optimized, thus improving the quality of the seminal doses.