pH estimation of semen

HYDROGEN ION CONCENTRATION or pH OF THE SEMEN

  • The pH of the domestic animals at the time of collection is having practical value in accepting or rejecting a semen sample.
  • Depending upon the concentration and activity of the spermatozoa the pH of the semen varies.
  • Since the sperm concentration and activity can be measured directly there is no better information gained with pH.
  • The pH of the semen can best be measured with pH meter. It can be measured with pH paper or by using dyes also.
  • The use of narrow range indicators is more convenient in the routine work of artificial insemination.

pH of semen can be assessed by

  • pH paper
  • Indicator dyes (Bromothymol blue or Bromo cresole purple or Phenol red).

pH paper

  • It is more convenient for routine work.
  • Tear the paper strip from the indicator book (touch the paper only at one end).
  • Tip the torn end of the paper in a drop of semen.
  • Look for the first change in color.
  • Find the matching color on the cover book and note the corresponding pH.

Indicator dyes (Bromothymol blue or Bromo cresole purple or Phenol red)

  • Take two capillary tubes which are marked for equal volume
  • Take the semen in on capillary and dye in the other capillary up to the marked volume.
  • Add the semen and dye in a watch glass and mix it well.
  • Take the mixed solution in a clean capillary tube and the color is compared with the comparator set (which has set of capillary tube according to the pH).
  • pH of the semen is assessed by reading the matching capillary from the comparator set.
  • The ranges of pH that can be assessed by using different dyes are as follows.
    • Bromothymol blue - 5.2-6.8
    • Bromo cresole purple – 6.0-7.6
    • Phenol red – 6.8 – 8.4.

pH of semen of different species

Species pH
Bull 6.8
Stallion 7.4
Ram/Buck 6.8
Boar 6.8
Dog 6.7
Cat 7.4

pH of the semen affected during

  • Inflammatory conditions affecting the accessory sex glands
  • When bulls are used excessively – Alkaline pH
  • Incomplete ejaculation – Alkaline pH
Last modified: Monday, 11 June 2012, 12:15 PM