The new Italian fertility index

The Italian fertility index (IAF) of Holstein bulls has been updated in order to improve the selection schemes of Italian Holstein population, that is characterized by an increasingly lower fertility. The new IAF will be an important tool for the selection programmes and it will certainly have an impact also on the economic balance of the farm.

The main aim of the Italian fertility index is to maximise the cows’ conception rate (CR) at the first service: having heifers and cows that get pregnant at the first service allows to reduce managements costs of the farm.

However, the conception rate is a very difficult selection trait for several reasons:

• Low heritability;
• Not always available;
• Not the main character of selection.

Until now, the IAF was composed by direct traits (days to first service – DTFS, 56 day non return rate – NNR56, days from first to last insemination – IFL) and indirect traits (dairy form and 305-day milk yield EVM). However, this index had several minuses.

• The new index takes into account both cows and heifers (90/10), for a faster and most accurate index;
• DTFS was introduced instead of AFI: now the number of cull cows loweres the fertility index. Cull cows were not considered before;
• The new IAF is now composed by 8 different traits (see the tables below) and a huge number of data are now continually updated.

Today, the selection allows to obtain well-constructed and efficient animals and the introduction of these little changes in selection index can make a huge difference in the Holstein population. Not only Italian selection is moving in this way but also Germany and France. Having a fertile herd allows to avoid ovsynch and hormonal protocols that do not fix the root problem and create consumers’ ethic disappointments.

Italian selection is based on what Italian breeders need: productive and healthy herds and above all.. high fertility!