Influence of timing of gain on growth and reproductive performance of beef replacement heifers

摘要: Our objective was to determine whether beef heifers could be developed by delaying the majority of weight gain until last third developmental period before onset breeding season. Spring-born Angus x Hereford were used in each two consecutive years and allotted at weaning either .45 kg/d for entire (yr 1 = 159 d, n 40; yr 2 168 EVENGAIN) or .11 from d 0 112, followed .91 112 1, 40) 2, LATEGAIN). Body weights condition scores determined 0, 1) 2). Heifers subjected a 60-d Frame pelvic areas conclusion Actual daily gains EVENGAIN .60 .51 kg/d, respectively. LATEGAIN gained .25 .05 during restricted phases 1.14 1.32 accelerated growth season puberty not different between treatments year. Age did differ but, age delayed (P < .01) (406.9 d) compared (386.3 heifers. The had similar areas, frame scores, body First-service conception rates both groups (55.5 vs 55.3%). In tended .18) have an increase first-service rate (71.1 56.4%). No treatment differences occurred average overall pregnancy BW on 12 2.5% (not statistically significant) less feed respectively, We interpret these data indicate that late heifer development may decrease costs without detrimental effects reproductive performance.