EBV Methods

The breeding values (BV) for milk, fat, protein and somatic cell score have been jointly estimated using a so-called Multiple Trait Random Regression Test Day Model. Milk samples from all lactations are included in the evaluation. The model considers the cows’ individual lactation pattern, thus also providing a BV for persistency for both cows and sires. Breeding values for somatic cell scores are also published for cows and sires.

Breeding values for conformation traits (linear description and classification), milking speed (based on scores given by farmers as part of the linear description) and temperament during milking are estimated using a BLUP-animal model. Conformation traits are evaluated in groups (frame, rump, feet & legs, udder, teats including milking speed and final scores) (multiple trait model). The evaluation includes data from all lactations.

For estimation of breeding values for longevity a so-called survival analysis is performed, which allows for the inclusion of data on still living sires’ daughters.

In the EBV for female fertility, the five individual breeding values non-return rate heifer, delay time heifer, resting time, non-return rate cow and delay time cow are combined to a fertility index (EBV fertility). The delay time corresponds to the period between the first and the successful insemination of an animal. Thus, the service period in cows is included in the EBV as a combination of resting time and delay time. The cattle traits are weighted 1/12 each, the cow traits non-return rate and delay time are weighted 1/4 each, and the resting period is weighted 1/3.

The breeding values for calving ease (calf survival and calving ease) are estimated using a multiple trait sire model. Besides the direct calving ease (calf’s influence) also breeding values for the cow’s influence (maternal calving ease) have been estimated.

The breeding value estimation meat comprises the traits slaughter weight, conformation (CH-TAX) and fat cover for the two slaughter categories bank calves and bank animals (bulls, heifer, steers). It is based on the results of the neutral valuation in the slaughterhouses by Proviande. The routine EBV takes place twice a year in June and December and is carried out by Mutterkuh Schweiz.

The breeding values (BV) are estimated across all breeds and then standardized within the breed to an average of 100 by means of a breed constant. The publication conditions have been defined uniformly. The BV are published if slaughter data of at least 20 bank calves or bank animals are available for AI bulls or of at least 10 bank calves or bank animals for natural spring animals.