Kappa-casein / CSN3 A/B/E - Cattle

About kappa-casein

Kappa-casein, encoded by the CSN3 gene, is an important milk protein involved in casein micelle stability and milk coagulation properties. This combined test determines the A, B and E variants of kappa-casein.

For dairy-oriented breeding this is valuable information. Kappa-casein variants can influence milk composition, curd formation, cheese yield and processing quality. The B variant is often considered favourable for cheese-making traits, while the E variant is important because it changes the final CSN3 profile of the cow.

Practical value of this test

• A/A: the cow produces kappa-casein A.
• A/B or B/B: B is present and can be relevant for selection on cheese and processing traits.
• A/E, B/E or E/E: E is present and should be considered in breeding and production decisions.

The result supports selection for milk protein profile, strategic mating and better alignment between genetics, milk production and processing goals.