Sheep Industry News August 2021

Often An Industry Leader, Texas Slow to Adopt Genetics REID REDDEN & JAKE THORNE Texas A&M AgriLife H istorically, Texas producers have pioneered several significant advancements in the American sheep industry, but have not remained present-day leaders tests in the late 1940s at the Sonora, Texas, experiment station with Rambouillet sheep. This test ran for nearly 70 years and certainly accomplished the original goals of improving fleece quality and growth rate, in conjunction with promoting a dual purpose phenotype.

when it comes to utilizing some key genetic technologies. Long-standing production constraints have limited inno vation in the seedstock industry in Texas, making the state ripe for a technological revolution that could help producers overcome several of their most significant challenges. Technol ogy that explores and quantifies genetic capability might be the golden ticket for the Texas sheep industry to reach its full potential. Texas is No. 1 in the United States in sheep numbers and, in many ways, has been forward-thinking in the area of small ruminant production. While mohair and wool were prominent commodities produced by Texas for decades, a paradigm shift has occurred in the 21st century with importation of breeds not requiring shearing and adaptable to the dry, semi-arid landscape of the Edwards Plateau region – the epicenter of small ruminant ranching in the state. Rambouillet sheep still number in the hundreds of thousands, but it is estimated that more than half of the sheep in Texas are now hair sheep, pre dominantly Dorper. Prior to the removal of the wool and mohair incentive, wool was the most valued trait and improvement of such has long captivated progressive ranchers and the research arm of Texas A&M. Texas formed one of the first centralized ram

The National Sheep Improvement Program was formed in the late 1980s to allow on-farm data to translate into Expected Progency Differences – now called Estimated Breeding Values. This system is an improvement over centralized testing as it allows for evaluation of other critically important traits overlooked by the ram test, such as reproduction, range fitness and parasite resistance. However, recording animal lineage is a critical component of utilizing NSIP. The majority of seedstock in Texas are raised under ex tensive conditions. They are range lambed, and if they are individually identified, it isn’t until after weaning. This cer tainly promotes traits such as hardiness, but limits the ability to capture pedigree and makes collection of production data almost impossible. To work around this, Texas Rambouillet Superior Genetics was formed in the 2000s. This group of West Texas Rambouillet breeders pooled their best sheep into one flock and enrolled into NSIP. The initial results were encourag ing, but keeping up with the off-ranch data collection became problematic for the group and unfortunately this project dis solved. This approach was ahead of its time and could have had long-term impact on the regional industry as similar strate gies have been used in other countries to develop genomically enhanced breeding values. The emergence of Dorper sheep in Texas – in lock step with the rapidly growing nontraditional market that prefer these smaller framed lambs – has completely changed the industry landscape. This breed is quite adaptable to Texas range condi tions and requires less management than fine wool sheep. Yet neither Dorper, White Dorper or other hair/shedding breeders in Texas adopted advanced genetic improvement technologies, such as NSIP. In contrast, exhibition at stock shows and visual classification standards have dictated perceived genetic poten tial and the value of breeding animals. In other sheep breeds, this approach has failed to measur ably improve the genetic potential of range sheep and, in some cases, has promoted genetic change that is counterproductive to commercial production. Since 2015, Texas A&M AgriLife has enrolled a group of Rambouillet and Dorper sheep into NSIP to demonstrate how

Dorper ewes are group-mated and range lambed with minimal assistance, but pedigree and NSIP records are maintained thanks to DNA technology.

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