The effects of supplementing beef cows grazing cornstalk residue with a dried distillers grain based cube on cow and calf performance

Abstract

ABSTRACT Multiparous beef females (n = 832) were used to study the effects of supplementing cows grazing cornstalk residue with a dried distillers grain based cube on cow and calf performance. Cows were blocked by age, BCS, BW, and calving date and assigned randomly to 1 of 2 treatments: 1) supplemented with protein and energy using a dried distillers grain based cube or 2) not supplemented (control) during the last trimester of pregnancy. Cow BW was similar at initiation and at the end of cornstalk grazing, and at the initiation of the breeding season. Supplementation did not affect BCS at the start of breeding (5.4 ± 0.1) or at the initiation of cornstalk grazing the subsequent year. Body condition score of supplemented cows was greater (P = 0.02) at the end of cornstalk grazing compared with that of control cows (5.6 vs. 5.4 ± 0.1). Calving interval, calf birth weight, and calf weaning weight were not different. Percentage of cows cyclic before breeding and final pregnancy rates did not differ. Heifer progeny (n = 306) retained as replacements were similar in initial weight (277.5 ± 10.2 kg), final weight (351 ± 11.5 kg), initial and final BCS, and ADG (0.45 ± 0.04 kg/d). Age at puberty, response to synchronization, AI conception and pregnancy rates, and final pregnancy rates were not different. Supplementation of a dried distillers grain based cube to cows grazing cornstalks improves BCS in the last trimester without affecting reproduction, calf performance, or reproductive performance of heifer progeny.