AN S 226 Lecture Notes - Lecture 8: Red Angus, Birth Weight, Gestation

• School: Iowa State University
• Department: Animal Science
• Course: AN S 226
• Professor: Dr. Brad Skaar

Document Summary

Nce: mixed model methodology, any quantified trait can be assessed. Epd: expected progeny difference, the transmitting ability of an individual, differences are what count. Typical reproductive traits evaluated: birth weight, calving ease (direct, maternal, calving ease: first calf versus mature, gestation length, scrotal circumference, stayability, heifer pregnancy. Hpg: heifer pregnancy epd, example: red angus, differences in daughters" ability to conceive to calve as two year old, units = % Typical repro traits evaluated: birth weight, calving ease (direct, maternal, calving ease: first calf versus mature, gestation length, heifer pregnancy, dispostion. Pounds of birth weight ( mature dam equivalent) Example: bull a: 5. 0 and bull b: 2. 0. Example: bull a: -7. 0 and bull b: +2. 0. Example: bull a: 104 and bull b: 96: gestation length. Example: bull a: 0. 5 and bull b: -1. 0. Reproductive traits maternal effects: daughters calving ease. Example: example: bull a: -7. 0 and bull b: +2. 0. Example: bull a: 104 and bull b: 96.