Daughter fertility index (9 % of TMI)
The Norwegian Red is likely the most fertile breed of dairy cattle in the world, due to sustained selection for increased fertility for over 50 years.
The fertility index was recently improved by replacing non-return rate with number of inseminations. Number of inseminations is biologically very similar to non-return rate, but it has more genetic variation since cows requiring more inseminations are penalized more heavily than cows with just one unsuccessful insemination.
Two traits for number of inseminations (cow and heifer) and calving to first insemination (CFI) are included in the daughter fertility index.
|Traits||Relative weight (%)|
|Number of inseminations, heifer||22.0|
|Number of inseminations, cow||45.0|
|Calving to first insemination (CFI)||33.0|