Beef Heifer Development Robert L. Larson, DVM, PhD, ACT, ACVPM-Epi a, *, Brad J. White, DVM, MS a , Shelie Laflin, DVM b INTRODUCTION Replacement heifer management has a large influence on the reproductive success of beef herds. Overall herd productivity increases when a high percentage of heifers become pregnant early in the first breeding season and a high percentage of first- calf heifers (primiparous cows) conceive early in the breeding season for a second pregnancy. 1–4 In order to become pregnant early in the breeding season as a heifer (nulliparous), deliver a live calf, and become pregnant early in the breeding season as a first-calf (primiparous) cow, management of heifer development must optimize nutrition, heifer maturity (puberty) at the onset of breeding, bull fertility, and overall reproductive success. The authors have received grants, or research contracts, from the National Cattlemen’s Beef As- sociation, the United States Department of Agriculture, Zoetis Animal Health, Merck & Com- pany, CEVA Biomune, Boehringer Ingelheim Vetmedica, and Merial Animal Health. a Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, KS 66506, USA; b 14075 Carnahan Road, Olsburg, KS 66520, USA * Corresponding author. E-mail address: RLarson@vet.ksu.edu KEYWORDS  Beef heifer  Puberty  Reproductive soundness examination of heifers  Estrous synchronization  Artificial insemination KEY POINTS  In order to become pregnant early in the breeding season as a heifer, deliver a live calf, and become pregnant early in the breeding season as a first-calf (primiparous) cow, man- agement of heifer development must optimize nutrition, heifer maturity at the onset of breeding, bull fertility, and overall reproductive success.  Examination of yearling heifers before breeding can provide information on the current pu- bertal status of the group and allow better predictions regarding success of the breeding season.  Data used in the evaluation of breeding soundness of replacement heifers include body weight, days of age, reproductive tract maturity, and potentially pelvic area; the optimum timing of a reproductive soundness examination will depend on the nutrition, breeding, and marketing plans for specific herds.  Using the Kansas State University 3-point system (R, I, and P), veterinarians classify pre- breeding heifers as ready, intermediate, and problem. Vet Clin Food Anim 32 (2016) 285–302 http://dx.doi.org/10.1016/j.cvfa.2016.01.003 vetfood.theclinics.com 0749-0720/16/$ – see front matter Ó 2016 Elsevier Inc. All rights reserved.