Information for Vet Referrals

Computer Assisted Semen Analysis (CASA) Report

The computer evaluates semen by ‘tracking’ individual sperm and by measuring their movements to classify them as motile or static. The motile sperm are subdivided as either progressively motile or motile.
The results sheet gives counts of each class of motility and the percentage of the population measured.

Motility – Total motility and progressive motility are correlated positively with increased fertility and so the greater the motility parameters the better.

Morphology Evaluation 
Morphology – Phase contrast microscopy is used to evaluate the morphology (shape) of sperm. A minimum of 70% normal morphology is acceptable.
Concentration – is given in millions of sperm per ml of semen.


Flow Cytometer Parameters

Percentage viable and intact acrosome – gives the percentage of live sperm that have an acrosome capable of penetrating the outer membrane of the ‘egg’ of the cow. The greater the percentage of these sperm the better.

Percentage polarised mitochondria – sperm need energy produced by active (polarised) mitochondria to reach the oviduct and egg. The greater the percentage of ‘active’ sperm the better.

Percentage viable – gives the percentage of sperm with an intact plasma membrane and are therefore classed as live. The greater the percentage of live sperm the better.
Targets of the above measurements are ‘traffic light’ coded based on industry standards, existing research and our own laboratory reference ranges.

We draw your attention to results marked with * as they fall outside “normal” parameters

If you have any questions, please do not hesitate to contact us.