Method for determining the quality of an animal's semen

A method of determining the quality of an animal's semen, comprising the steps of:

• collecting at least one fresh or frozen semen sample,
• measuring at least one absorption spectrum of at least one sample of said semen,
• determining from said at least one absorption spectrum Xj, a value of the first derivative of the absorptions X′j,
• calculating one or more parameters, representative of the quality of said semen, selected from the group consisting of concentration Y1, mobility Y2, progressive spermatozoa rate Y3, viability Y4, percentage of live spermatozoa with stable phospholipids Y5, mitochondrial potential Y6, percentage of spermatozoa with peroxidised lipids Y7, percentage of spermatozoa with an intact acrosome Y8, the total antioxidant capacity TAC Y9, fatty acid composition Y10, percentage of spermatozoa having a normal morphology Y11, the osmolarity Y12 and glutathione GSH level Y13, non-return rate at 56 days Y14, the non-return rate at 90 days Y15, pregnancy diagnosis Y16, from said first derivative of the absorption X′j;
• previously determined for the determining of the quality of said semen.