ASA Launches Feet and Leg Scoring Recommendations |
By Lane Giess, Director Commercial & Nontraditional Data Programs |
There has been a significant amount of buzz in the industry lately when it comes to structural soundness in genetic evaluation. With workshops educating breeders across the country, multiple presentations happening at national conferences, and articles in countless publications, feet and leg structural evaluation obviously matters to beef producers — seedstock and commercial alike.
The ASA science team has been hard at work developing further understanding of the genetic control of feet and leg structure in beef cattle and encourages members to start thinking about structural evaluation in their own herds.
While not new to dairymen, feet and leg structure evaluation is in its relative infancy for the beef industry. Through a research project at Kansas State University funded by the American Simmental Association, Red Angus Association of America, and the Kansas Global Food Systems Initiative, multiple traits related to feet and leg structure were evaluated and tested in the most comprehensive research project of its kind in beef cattle. Approximately 4,000 animals from both the Red Angus and Simmental breed populations were scored for 14 traits relating to structure.
Dr. Bob Weaber, professor and extension beef cattle specialist at Kansas State University led the project. “The objectives were to understand the genetic relationships among hoof, leg, and limb angulation attributes — especially any differences between the front and rear limbs. We also wanted to test the granularity of the scoring system to determine information loss using a simple categorical system,” Weaber commented.
The study provided insight for ASA and IGS breed partners to develop educational material and recommendations for breeders to start evaluating their own herds.
Three traits were identified to be issues in the breed population worth exploring further: 1) Claw set and divergence; 2) Hoof angle and heel; 3) Hock angle or rear leg side view.
Curvature or divergence in claw set disrupts the surface area on the base of the hoof. This often appears as a scissor or corkscrew claw, where the most severe cases result in one claw growing outward and crossing over the other claw. Cattle often experience shortness of stride and apparent painful movement with this phenotype.
Hoof angle and/or heel depth issues can lead to shallow-heeled cattle, which can cause toes to grow out and lengthen. Inversely, too much depth of heel results in a rigid hoof and pastern angle, limiting an animal’s flexibility of motion.
Though the previously mentioned traits affect hoof conformation, structure issues also manifest themselves in the limbs of cattle, notably the hock and rear leg set. Cattle with extreme straightness are limited in their mobility as are animals that experience over-flexion of the hock joint.
Feet and Leg Recommendations
Developing a set of educational guidelines for feet and leg structure for ASA members to better select and evaluate their own animals has been a high priority for the ASA science team. While much of the research regarding the use of feet and leg data in genetic evaluation, as well as structure’s impact on economically-relevant traits is still ongoing, membership can contribute to this research by voluntarily sending any data they collect on three traits: Claw Set, Hoof Angle, and Rear Leg Side View (See Figures. 1–3).
Weaber stressed the importance of breeders familiarizing themselves with feet and leg structural evaluation. “Seedstock cattle will continue to be evaluated for a wide range of economically important traits for the foreseeable future. Commercial cattle producers making sizeable investments in genetics are elevating their expectations relative to foot and leg conformation and durability. As such, seedstock producers seeking repeat customers for high-value bulls should strive to breed cattle with foot and leg longevity in mind,” Weaber emphasized.