Semen Quality Evaluation and Bull Grading System
Semen quality evaluation and bull grading system is a standardized method used to assess the reproductive potential of breeding bulls. This evaluation helps determine whether a bull is suitable for breeding based on specific semen parameters and physical characteristics.
A point of system is used to assign a score for semen quality. This point system is based on addition of scores obtained by scoring separately the scrotal circumference, sperm motility and morphology.
Scrotal circumference or size of testes is an indirect measure of semen producing capacity of an animal, which explains its inclusion in a semen quality determination.
The maximum score assigned for each criterion is:
| Criteria | Grade |
|---|---|
| Scrotal circumference | 40 points |
| Motility | 20 points |
| Sperm morphology | 40 points |
Based on the total score, the bulls are classified as shown below (Ball et al.,1983):
| Category | Total Score |
|---|---|
| Satisfactory | > 60 |
| Questionable | 30-60 |
| Unsatisfactory | < 30 |
