by Darol Dickinson

I have read that when a bull and cow are mated, each parent offers as many as 100,000,000 different DNA markers. When these determiners funnel down to form a calf, certain bits from each parent contribute to the new life. But the combinations may differ in 50 million ways for full siblings. The odds are in the mega-millions that even full siblings will look exactly alike. Some almost do, but sometimes even identical twins do not show family similar resemblances. The unpredictable results are what God decides to let flow down the mysterious genetic funnel.

I'm not a degreed professional in this science. But for more than fifty years I have raised, owned, and watched over 20,000 Texas Longhorns---some very closely. Some traits in these cattle happened over and over. Those common, recurrent variables were easy to calculate and predict. Others, however, were rare and occurred only in a tiny fraction of births.

Three scientific terms can describe exceptional new calves: mutation, outlier, and sport. As professional producers, let's use "bounce" as a common noun to include all three outcomes.

~ Mutation: the changing of the structure of a gene, resulting in a variant form that may be transmitted to subsequent generations, caused by the alteration of single base units in DNA, or the deletion, insertion, or rearrangement of larger sections of genes or chromosomes: "mutation is, ultimately, the only way in which new variation enters the species."

~ Outlier: a person or thing that is atypical within a particular group, class, or category. It can be far better or far worse than the specimen average.

~ Sport: a plant [or] animal, which exhibits abnormal variation or departure from the parent stock or type in some respect, esp. in form or colour; a spontaneous mutation; a new variety produced in this way (Oxford English Dictionary, def. 6.b).

Despite their differences, for this discussion all three terms illustrate the collective concept of a "genetic bounce."

Even though every plant in a commercial tulip field may have almost identical DNA, sometimes one blossoms differently. The newcomer is a mutation, outlier, or sport. Such genetic bounce happens rarely, suddenly, and unpredictably. It's hard to know when, which, and how a bounce will occur. It's even harder to identify, reproduce, or even evaluate a bounce. What if it embodies the most-valued trait in the field--or is worthless?

In studying the bounce in Texas Longhorns, we can examine many traits such as fertility, birth weight, rate of gain, conformation, hide and horn color, coat pattern, horn angle and twist, disposition, intelligence, and so forth. Unfortunately, these factors are sometimes subjective and always almost elusive. Considering all of these traits, other historic virtues, and their percentages would take a long time and a massive computer. Analyzing them manually would drive one over the edge.

For the practical purposes of this article--to understand bounce in Texas Longhorns it's best to begin with one convenient, factual calculation. Tip-to-tip (T2T) horn-measurement is the easiest and most objective trait for understanding data, so let's use that method to look at some important genetic bounce history.

In the early 1980's, a few cows began to stand out, including the celebrated Doherty 698 ($120,000). Her sire, Senor Mulege, a Wichita Reserve (WR) bull, carried just a hair over 40" of horn T2T. I'm told that Doherty 698 was 75" in her later years--well above her ancestors. When flushed for embryos, it was a serious and difficult decision to identify which bull to use. She was so superior to her ancestors, what sire would push her excellence forward? Because no collective data or plan was available, the shotgun approach was used, and flushed her with 11 different sires over a 24-month period.

From these flushes, Doherty 698 produced many progeny above herself and well above the breed. Two of her sons, Overwhelmer and Phenomenon, bounced above the ceiling. They were not only better than everything in their ancestry. They sired progeny well above themselves to take even larger steps in genetic improvement. Their data easily proved a successful bounce.

In sharp contrast, many of the most famous Texas Longhorn cows and bulls never produced any calves superior to themselves. Every offspring was below them in quality. They produced no upward genetic bounce.

Some of those great-but-unproductive individuals were not mated correctly. Therefore, it was nearly impossible for them to contribute an upward bounce. With the right matings, however, they could have produced genetic improvement. Here are two notable successes.

Rio Grande reached a top measurement of 80.875" T2T. He sired 14 bulls over 80", two over 90", and one cow over 100". That cow was BL Rio Catchit, one of the most profitable ever with an over 20" bounce. That is a measurable, and notable bounce of great profit to many, well over her sire and dam.

Hunts Command Respect was 77.75" and sired many over-80" and over-90" progeny. Had he not had the bounce factor, his family would have been totally unknown today.

Accurately identifying bounce takes detailed data from 50 to 100 of a bull's progeny. The bounce begins to show when cattle are retained in the same herd with year-to-year comparative analysis. Cows are harder with fewer progeny.

It's hard, however, to identify bounce and make a profit with cattle from different herds. When they are bought, sold, and relocated, their data are comingled. As a result, comparisons are not always statistically valid. Bounce could be a possible factor, but producers typically just don't watch for it. If they do, the data are invalid or lost in comingled ownerships. The bounce may be there but unobserved. Potentially prepotent bulls become steers, eliminating any future stature as sires. Undetected cows unfortunately rarely or never become the dams of champions.