Further drop in EBI values of top dairy bulls
The EBI (Economic Breeding Index) value of some of the country’s top bulls has dropped following the latest ICBF (Irish Cattle Breeding Federation) evaluation run.
The average EBI value of the top 75 active sires available in AI has plummeted by €15/head when compared to the corresponding evaluation carried out in February of this year. The average EBI of the top 75 bulls now stands at €214 – down from €229.
According to the ICBF, the drop is primarily due to the fall in the milk-sub index, which has dropped by €13. This, it says, is a result of over 140,000 new animals with milk data between December 2016 and August 2017 (first lactation animals) being factored into the evaluation.
In addition, fertility sub-index and health sub-index values dropped by €2 and €3 respectively. However, the EBI reliability figure for the top 75 bulls has increased to reach 63%.
Despite the difference in averages between the February and August evaluation runs, the ICBF said: “An analysis of the top 75 bulls on the active bull list shows that there is a very strong correlation (0.81%) between the February evaluation and the current August run.”
However, it did identify one bull – SEW – as being an outlier.
This comes as 550 daughters have been added to SEW’s proof for the first time. This, in turn, means that his milk figure is now based on a domestic proof instead of the previous GS (Genomically Selected) proof.