The number of Irish-bred bulls is largely dependent on the number of bulls being progeny tested.
Typically about 40-50 bulls have been tested each year. However, the target has been to test 100 bulls each year. In order for high EBI Irish bulls to dominate the list this target must be hit.
Graph 1 (above) illustrates the trends in the countries of origin for bulls over the past 11 years.
The Oman effect
The fact that the Bull O-Bee Manfred Justice -- "OJI" has been the sire of so many sons on the bull lists over the last few years has always been a concern for farmers attempting to avoid inbreeding on their cows.
In order to counter this problem, Gene Ireland has moved away from selecting sons of "OJI" over the last two years.
This is one of the many benefits of a national progeny test programme in that such issues can be managed and avoided in time.
The table (below) and graph 2 (right) show that there are less sons of "OJI" on this year's list and also that the number of "OJI" sons on the list has been decreasing over the last two years.
The 75 top-ranked bulls on the list have an average EBI of €203 (see graph 3, above), slightly ahead of the spring ranking's average of €198. They range from €265 down to €176. However, we are beginning to see the start of a levelling off of the average EBI figure for the top 75 bulls in recent years.
Part of the reason for this may be the collapse in numbers of bulls in progeny testing. IBR outbreaks in 2010 and 2011 were the main cause of this slump, but it is hoped that in 2012 the number of bulls being progeny tested can be increased again, up towards the ultimate goal of 100 bulls.
Five things to remember when selecting your bull:
•It is important to note the source of a bull's proof when choosing sires from the list. A bull may have received his proof based on data recorded on his daughters' performance or he may be a genomically selected bull.
While the latter will tend to have the highest EBI scores, the reliability of their data is generally lower than that of the bulls with figures based on their daughters' performance.
In order to balance the risk of using a bull with low reliability, together with the tremendous genetic gains that can be achieved by using such a bull, farmers are strongly urged to use a minimum of five AI bulls from the list.
•Bulls with low availability are not included in the ICBF sire advice programme, as large quantities of straws cannot be guaranteed. While the AI companies do have a limited amount of straws available for these bulls, farmers should order straws early so as to avoid disappointment.
•Identify which EBI sub-indices your herd is low in. Your herd sub-index information is available on the Herdplus EBI report that ICBF generates for every herd that is signed up to Herdplus. Pick an initial panel of bulls based on this.
•Refine your list of bulls, taking other factors into account such as calving ease, inbreeding, price and availability.
•The ICBF sire advice programme can help you order your semen supplies and also allocate the chosen bulls to your cows in such a way that in-breeding is avoided without you having to think about it.