What is a Superior Settler?
Every A.I. organization offers their own version of high conception sires. For more than 30 years, Select Sires' high conception sires have been recognized by the time-tested, industry-standard Superior Settler™ designation. However, we often get questions about a particular sire with high fertility that did not receive the Superior Settler designation. Did we miss one that should have been on the list? Usually not; high fertility is only one component in assigning the Superior Settler designation.
The Fertility Estimate Component
Numerous national and regional systems are available to estimate the fertility potential of A.I. sires. Sire Conception Rate (SCR) was developed by the USDA-AIPL and is now calculated by the Council on Dairy Cattle Breeding (CDCB). The SCR system includes data from most major processing centers and is the closest we have to a national system in the U.S. In the western U.S., many producers rely on Agri-Tech Analytics (ATA) sire fertility estimates calculated from large California herds contributing records to their processing center. In addition, most major A.I. organizations have their own in-house systems to gather records from cooperator herds and estimate sire fertility. Select Sires has two independent in-house systems; one for conventional semen and one specifically designed for gender SELECTed™ semen. In addition, Select Sires receives monthly updates of sire fertility estimates from Canadian Dairy Network (CDN). Fertility reports from other countries around the world are also collected on occasion.
All of the systems above use similar models to adjust for effects of environment (herd, month, year) and fertility of the female being inseminated (lactation, service number, milk production, etc.). With all of these systems available to evaluate sire fertility, it is easy to imagine that confusion is often generated when they produce conflicting results. It happens more often than many realize.
The Semen Quality Component
At Select Sires, each collection of every sire is subjected to an extensive analysis of numerous semen quality traits using state-of-the-art equipment, techniques and procedures. No semen makes it to inventory that is not capable of achieving acceptable levels of fertility. With that said, no matter where you draw a line, there will be some individuals above and below average in the population. Therefore, among any A.I. organization's lineup of highly fertile A.I. sires, some will produce semen that is slightly better or worse than another sire.
Superior Settlers Tie it all Together
In addition to the confusion generated when two sire fertility estimates do not agree, there is often even more confusion when the sire fertility estimates do not match the semen quality characteristics. Bulls that have outstanding semen quality and normal fertility potential (± 2 percent or 3 percent of average) happen all the time. On occasion some of these high semen quality sires may even have well-below average fertility estimates. It is not clear if this is due to an unidentified semen quality attribute that cannot be measured or detected in the laboratory or bad luck in semen distribution and use. The fact that many sires with well below-average semen quality characteristics often achieve well-above average fertility deviations clearly implies there is an element of luck and random chance in the fertility evaluation process.
Superior Settler designations are designed to remove luck, random chance and confusion from the process of selecting sires for fertility potential. First, the sire must have above average fertility potential on one or more of the numerous fertility evaluation systems outlined above with a significant number of services (more than 500) and minimal evidence of conflicting results across systems. Estimates with fewer numbers of services are less reliable and subject to change and when results across systems are in conflict, it may not always be clear which is correct. These sires are excluded from Superior Settler consideration.
Second, the sire must also maintain semen quality attributes that suggest he warrants the Superior Settler designation. Sires with above average fertility deviations but mediocre to below average semen quality characteristics are removed from consideration. Likewise, above average semen quality carries no weight if field fertility estimates do not support that the semen is generating extra pregnancies in the field. Superior Settlers must have both: above average fertility deviations and above average semen quality. Nothing is left to chance.
Keep Sire Fertility in Perspective
Although sire selection for fertility potential will help stack the odds in your favor to generate a few extra pregnancies from a given number of inseminations, it is important for producers to remember that in the big picture, the impact of sire fertility on overall herd conception rates is only one piece of the puzzle. Environmental and herd management factors affecting female fertility are also major components to achieving pregnancies. As a producer, you still need to select for genetic traits of economic importance to the herd first. Sires with fertility deviations within ±3 percent of average should be considered normal fertility. Producers may want to moderate the total number of doses they purchase for sires with below average estimates but they should not forego genetics of interest over concerns of fertility potential. Sire selection for fertility is a supplement (not a substitute) to an effective reproductive management program.