Breeding values - S-indices

 

In beef cattle 7 standardized breeding values are estimated: fertility, calving ease, milk, birth, weight gain, slaughter and conformation. Data included in the estimation of breeding values are:

 

• On-farm recording of basic information on pedigree, calving, non-A.I.-breeding, trade and culling, calf mortality, calving ease and weight of beef cattle at birth, 200 days and 365 days
• Results on daily gain and area of L.D. (muscularity) from the performance testing of bulls
• On-farm recording of calf mortality, calving ease and size of calf of dairy crosses
• Information on carcass weight and EUROP-score of carcass shape of beef cattle and dairy crosses
• Conformation scores

 

These 7 values are calculated into 3 main values; function, production and conformation. The values are weighted by different values according to each breeds breeding goals and are calculated - using economic weights - into a total merit index, the so called S-index. S-indices are published 4 times a year (in Danish only) and can be seen on the pedigree. A survey of the total system is shown in the figure below.

 

Calving interval   Survival, birth (maternal) Calving ease (maternal) Survival, 200 days (maternal Birth weight (maternal)   Birth weight (maternal) Weigth, 200 days (maternal) Weight, 365 days (matermal) Net weight gain (maternal)   Survival, birth (direct) Calving ease (direct) Survival, 200 days (direct) Survival, dairy crosses Calving ease, dairy crosses Size of calf, dairy crosses Birth weigth (direct)

FERTILITY       CALVING                  MILK           BIRTH

FUNCTION

 

Birth weight (direct) Weight, 200 days (direct) Net weight gain (direct) Net weight, dairy crosses Daily gain performance test   Carcass shape Carcass shape, dairy crosses U-figure (muscularity)

WEIGTH GAIN           SLAUGHTER

PRODUCTION

 

Bodytype Musclularity    Feet & legs

CONFORMATION

CONFORMATION

 

An Animal Model is used to estimate all breeding values of all traits recorded for purebred beef cattle. A modified version of the Animal Model is used for the traits recorded on dairy crosses. All dairy crosses are considered repeated observations of the sire and the genetic parameters are modified accordingly. The estimates are calculated seperately for 6 different breed groups and for 5 different groups of traits. 

 

The sub-indices and the total merit index are standardized to an average of 100 and a standard deviation of 10 for all animals belonging to the base. This means that animals that are above average has a S-index above 100 and animals that are poorer than average are under 100. Rigth now the Highland female with the highest S-index in Denmark has a value of 138 and the best Highland bull 134.