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SIRE SELECTION CONTINUED FROM PAGE 22

If an animal has too much angle to their pastern, they start putting pressure on the back of their hoof when they walk, causing wear that creates a “shallow heel.” Because the animal isn’t wearing down the front part of the hoof, they can get long toed. On the flip side, if an animal is too straight in their hock and upright in their pastern, then there’s not enough cushion and as they put their foot down when they walk, their hock and pastern have to absorb the impact, causing joint dis- comfort and potential swelling or even lameness. Simply put, Boardman said, “They’re not going to be able to get out and stride well.” Similar applications can be made to other physical charac- teristics that have corresponding EPDs, like birth weight. “To me, the most important thing is the first thing that comes out – their front feet, head and shoulders,” Boardman said. He advised identifying smooth-shouldered bulls with low birth weight EPDs for producers looking for calving ease but cautioned against single-trait selection. “The problem with only selecting for low birth weight is that producers may give up growth, performance and stout- ness,” he cautioned. “Typically, the main way that we have found to work around this is to shorten gestation length.” A bull that consistently throws shorter gestation intervals – something like 270 days instead of 283, for example – may very well be able to offer the best of both worlds in terms of calving ease/birth weight and growth. At the end of the day, Boardman recommends identifying the goals of your unique operation and balancing EPD utilization with phenotypic evaluation in order to find the bull that’s going to give you the biggest genetic advantage and have some lon- gevity. Perhaps when Oscar Wilde said, “Everything in modera- tion,” he was doing his homework preparing to buy bulls.

practices. After identifying operation goals and evaluating EDPs, Boardman recommends a physical inspection of the animal being considered for purchase. “Phenotypically, spend a lot of time studying them structur- ally,” he said. “You want these bulls to last a couple of sea- sons, so you don’t have to buy new bulls every single year.” Structurally sound livestock often “fill their tracks” when they walk – meaning their hind foot fills the track their cor- responding front foot made. Further, Boardman explained, when an animal is considered sound, they stay level in their topline. To accomplish these traits, he explained, “We want a 45-degree angle to the pastern with a square claw set.”

SGBI EPDs

Birth Weight (BW)

Pounds

Weaning Weight (WW)

Pounds

Yearling Weight (YW)

Pounds

Maternal (MAT or MILK)

Milking ability of an animal’s daughters

Total Maternal (T MAT)

Total difference in weight of a bull’s daughters’ calves at weaning

Scrotal Circumference (SC)

Centimeters

Heifer Pregnancy (H Prg)

Probability that a heifer will get pregnant as a yearling

Breed Back (Brd Bk)

Probability a 2-year-old will be pregnant given she was listed as pregnant as a yearling

Hot Carcass Weight (HCW)

Differences in progeny carcass weight

Marbling (MARB)

Genetic differences in marbling potential passed from a sire to his offspring

Ribeye Area (REA)

Objective assessment of muscling and an indicator of total muscle in the carcass or live animal

Fat Thickness (FAT)

Differences in carcass fat thickness between the 12 th and 13 th ribs

Tenderness (Sh F)

Predicts the pounds of shear force needed to cut a steak

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