Age and Weight at Puberty of Crossbred Heifers Sired by Charolais, Limousin, and Simmental Bulls

Abstract

and 292 kg, respectively). Heifers from Angus and Hereford dams were aboul 22 days older (P < 0.01) at puberty than heifers from Shorthorn dams (median 347 and 346 vs. 324 days). Heifers with high preweaning grqwth rates attained puberty at an earlier age 1r : *0.24; P < 0.01). Day of birth within the year had a significant effect on age and weight at puberty; i.e., heifers bom early in the calving season were older and heavier at puberty. Weight at puberty was associated with weaning weight (r : 0.61;P < 0.01), birth weight (r : O.4l; P < 0.01), and preweaning average daily gain (r : 0.54;P < 0.01). Calves that were heavy at birth tended to be heavy at weaning, and heavy weaning weights, in turn, were associated with heavy weights at puberty. By l5 mo of age,997a of all heifers were cycling.

The effects of maternal calving date and calving interval on growth performance of beef calves

“…Others have also reported that early calving cows produced heavier weaners (Morris & Cullen, 1988;Marshall et al, 1990;Garcia Paloma et al, 1992;Rege & Famula, 1993). The higher pre-weaning average daily gains of early born calves are significant, as it has been reported that heifers experiencing faster pre-weaning growth rates reach puberty at younger ages and heavier weights than slower growing contemporaries (Wiltbank et al, 1966;Brown et al, 1972;Laster et al, 1972;Swierstra et al, 1977). 0.06 ± 0.003 * * ** Significance of main effects (p < 0.01); a-e means without common superscripts within the same column and effect category differ (p < 0.05)…”

Estimation the genetic parameters for age at first calving in Charolais and Limousine breeds

“…The heritability for reproduction traits was: The age at the first calving was shown in table 1. (Swiestra et al, 1977). In others meat breeds, the age at puberty was 464.6 in Angus, 478.6 in Hereford and 493.3 in Creole breed (Pardo et al, 2018).…”

Puberty in Beef Heifers: A Review

“…Pre-weaning growth has a greater influence on puberty in heifers than postweaning growth (Joubert, 1954;Dufour, 1975;Swierstra et al,1977;Little et al, 1981;and Clanton et al,1983). Heifers that experienced slower pre-weaning rates of growth (200 g/d) reached puberty at older ages and lighter weight than those that grew faster (400 g/d) (Wiltbank et al, 1966).…”