Developement and Management of Heifers for Controlled Breeding Programs

Cow-calf producers require a consistent source of replacement females in order to maintain the size of the breeding herd at the desired level. Replacement females may be produced internally or acquired from external sources. This discussion will focus upon the critical control points that range from the selection criteria used in mating decisions to produce potential replacement heifers to the factors that influence successful rebreeding of the first-calf heifer. Heifers must attain puberty and conceive before 15 months of age to meet the goal of calving at 2 years of age. In order to successfully enter the cow herd, replacement females must be developed, conceive early in the breeding season, produce a live calf and conceive as a first-calf heifer. Heifer age and body weight (BW) significantly influence the onset of puberty. General guidelines have been proposed for target BW at specific stages of development relative to expected mature BW.