Cogent Breeding Ltd has pioneered the technology for sexing semen and was the first company in the world to commercially offer sexed semen in 2000 working with dairy breeds.
This was particularly useful for dairy farmers who wanted a stream of dairy heifers to build up replacements.
According to Cogent, using sexed semen has many advantages for breeders and producers including speeding up the genetic process, biosecurity through reducing the numbers bought in and it gives selection options.
Using a technique known as flow cytometry, Cogent can evaluate precisely the amount of DNA in a sperm cell and the sperm is labelled with a DNA seeking dye.
In cattle, male sperm cells carrying the Y chromosome contain 3.8 per cent less DNA than their female counterpart carrying the X chromosome. It is then possible to sort either the male or female sperm populations with over 90 per cent accuracy in sex ratio.
The technology also exists to discard dead or damaged sperm leaving an elite live population of the desired sex requested by a livestock breeder. The spermatozoa pass through the flow cytometer in single file, a laser beam analysing each sperm cell.
The sperm cell is encased by a single droplet of fluid and assigned an electric charge corresponding to its chromosome status. The stream of X and Y droplets are then separated by means of electrostatic deflection and collected into separate collection tubes for subsequent processing.
In the dairy industry, Cogent will say that producing heifer calves by this technique than having unwanted male calves destroyed at birth.
Innes Drummond, Reproductive Technologies Manager at Cogent Breeding Ltd, said that 600,000 bull calves were shot on farms as they were not required.
Cogent also uses a different freezing technique from other companies through a process known as harmony freeze.
"You could kill 50 per cent of your sample through freezing and thawing processes but Harmony Freeze is a Cogent exclusive using long needles of ice rather than sharp ice crystal, giving a more instant freeze and less use of toxic glycerol," explained Innes.
He also said they used more quality control measures than their competitors.
Both Cogent and Crawford Brothers recommend using sexed semen firstly on maiden heifers and then progress to other breeding groups but its application must also be done by the textbook.
"Single sexed semen is a way of farmers, either pedigree breeders or commercial farmers, maximising their incomes," he said.
Back to News Headlines