PSIV-A-7 - Decreasing the Frequency of Precalving Protein and Energy Supplementation Impacts Preweaning Growth of Bos Indicus-influenced Beef Offspring but Not Their Dam

Abstract: This experiment evaluated the impacts of frequency of dried distillers grains (DDG) supplementation during late gestation on subsequent performance of cow-calf pairs. On day 0 (September), 120 multiparous Brangus cows (body weight, BW = 543 ± 4.6 kg; body condition score, BCS = 5.47 ± 0.09) were allocated into 1 of 20 bahiagrass pastures (6 cows and 4.7 ha/pasture). Treatments were assigned randomly to pastures (5 pastures/treatment) and consisted of cows offered no DDG supplementation (NOSUP), 1 kg/cow of DDG daily (7X), 2.33 kg/cow of DDG every Monday, Wednesday, and Friday (3X), or 7 kg/cow of DDG every Monday from day 0 to 77 (1X; total of 77 kg/cow of DDG dry matter for all supplemented cows). After calving (on average day 81 ± 7), all cow-calf pairs were managed similarly and remained on their respective pasture until calf weaning (day 342). Cow BW did not differ among treatments (P ≥ 0.13). Cow BCS on day 77 and at the start of the breeding season (day 140) were greater for supplemented vs. NOSUP cows (P ≤ 0.02) but did not differ among 1X, 3X and 7X cows (P ≥ 0.64). Overall plasma concentrations of glucose were greater for supplemented vs. NOSUP cows (P ≤ 0.05) but did not differ among 1X, 3X and 7X cows (P ≥ 0.44). Calving percentage, calving date, percentage of male calves at birth, and calf birth BW did not differ among treatments (P ≥ 0.15). Calf BW at weaning were lowest for NOSUP and greatest for 7X calves (P ≤ 0.05). Calf BW at weaning did not differ between 1X and 3X calves (P = 0.97) and both groups were intermediate (P ≤ 0.05). In summary, decreasing the frequency of DDG supplementation during late gestation did not impact pre- and post-partum performance of Bos indicus-influenced beef cows but reduced subsequent preweaning growth of their offspring.