Creating More Pregnancies

By: Patsy Houghton, President and General Manager, Heartland Cattle Company

Heartland Cattle Company is a 5000-head Professional Heifer Development and Research Center in southwest Nebraska. Over the past 26 years, we have developed and artificially inseminated (A.I.) over 105,000 beef heifers. We believe in 35 or 45-day breeding programs using visual heat detection and total A.I. There are no excuses for open heifers. We have consistently met our fertility goals: 70% first service conception rate (FSCR), 85% seasonal pregnancy rate (PR) for 35-day heifers and 90% PR for 45-day heifers.

Over the past few years, we’ve noticed more variation in the fertility of A.I. sires. Typically, the fertility of A.I. sires ranges from 50 to 90% for FSCR, with outlier bulls ranging all the way from 0 to 100%. We’ve also learned that, by itself, evaluating semen under a microscope for morphology, motility and morbidity is not always a good predictor of fertility.

Variations in FSCR means reduced seasonal PR, fewer calves born and less pounds weaned. This is why fertility is so important to a rancher’s bottom line. Any measure that predicts and/or improves sire fertility will help keep cow/calf producers in business, especially during tough market times!

The ability to identify A.I. sires that will consistently deliver a 70% and higher first service conception rate is a big step in the right direction. That’s why we pay close attention to the PregCheck™ fertility rankings GENEX provides. Using 100 as the base, PregCheck™ fertility rankings are calculated as an index and are designed to predict an individual sire’s frozen semen conception rate.

So, let’s compare two bulls with PregCheck™ fertility rankings. Bull A has a 104 PregCheck™ fertility ranking with 93% reliability versus Bull B with a 99 PregCheck™ fertility ranking and 75% reliability. At 93% reliability, we are confident Bull A will perform at 4% above the average of his peers for conception rate, and he will likely perform 5% higher than Bull B for conception rate. At only 75% reliable, there is still some uncertainty as to how Bull B will actually perform over time until he is bred to more females, but at this point Bull B is trending below the average of his peers.

We’ve had a number of opportunities to compare GENEX PregCheck™ fertility rankings to actual service sire fertility and are happy to report a nice correlation between the two. As the database expands, we believe PregCheck™ fertility rankings will only get better with time.

At Heartland Cattle Company, we appreciate the value of measuring economically important traits. Fertility tops this list! If we are weighing the pros and cons of two or more service sires, the bull with the higher PregCheck™ fertility ranking wins! We are also confident any sire that doesn’t meet reasonable conception rate goals will be removed from the GENEX lineup. In our eyes, this reflects integrity and customer commitment. All of us at Heartland Cattle Company want to thank GENEX for their proactive approach to solving what has become one of our industry’s biggest challenges!