This study assessed the effects of different prepartum supplementation plans on Nellore cows’ performance, metabolic responses, and early offspring development. Thirty-nine pregnant Nellore cows (224 ± 2.67 days of pregnancy, 5.3 ± 0.29 years of age, body weight 520 ± 15.2 kg, initial body condition score 6.0 ± 0.07) were assigned to one of four treatments: a control group receiving only mineral mixture ad libitum, and three groups receiving daily protein-energy supplements of 2, 4, or 6 g/kg BW for 60 days prepartum. Weights and body condition scores were evaluated at the start of the experiment, 7 days before calving, and at 45 and 90 days postpartum. Cows supplemented with 4 and 6 g/kg BW showed improved body weight and body condition scores prepartum and postpartum and had a shorter service period (p < 0.05). The highest blood urea nitrogen concentrations were observed in cows receiving 6 g/kg BW (p = 0.0124). There was a reduction in blood urea nitrogen at calving for the 6 g/kg BW group, while the control group showed an increase (p < 0.001). Non-esterified fatty acids concentrations were lower 21 days before calving for the 4 and 6 g/kg BW groups compared to the control (p < 0.05) and decreased postpartum for all treatments (p < 0.001). No significant differences were observed in calf birth weight or performance. Supplementing with 4 g/kg BW of protein-energy is recommended to enhance metabolic health and overall performance.

Forty multiparous Nellore cows, with an average body weight, body condition score, and gestation days of 533 ± 32 kg, 5.7 ± 0.4 points, and 198 days, respectively, were managed under continuous grazing on a Urochloa decumbens pasture and either received or did not receive 1 kg/day of supplement varying in the levels of inclusion of dried distillers grains (DDG) (Control, 0% DDG, 42% DDG, or 84% DDG) during the last trimester of gestation. The objective was to evaluate the effects of prepartum DDG supplementation on performance, reproduction, fetal development, and calf performance. A quadratic effect of supplementation on BW variation pre- and postpartum was observed (p < 0.05), with cows treated with 42% DDG showing higher BW gain prepartum and low BW loss postpartum. Cows supplemented with 42% DDG had lower levels of non-esterified fatty acids and β-hydroxybutyrate prepartum (p < 0.05). However, body weight-related metrics, such as condition score, carcass traits, and metabolic indicators, varied only by measurement day (p < 0.05). No effect of supplementation was observed on fetal development, calf metabolic profile, milk yield, or postnatal calf performance (p > 0.05). It is recommended to include up to 42% DDG in supplements for beef cows during late gestation grazing on low-quality tropical forage conditions.

The supply of metabolizable nutrients to suckling beef calves on pasture can improve their performance, increasing weaning weight and productivity in cow–calf systems. The objective was to evaluate the effects of dried distillers grains (DDG) inclusion on intake, digestibility, metabolism, and performance of suckling beef calves grazing tropical pastures. Forty-eight Nellore calves, 120 ± 35 days of age and 135 ± 23.4 kg of body weight (BW), were used. During 117 days, calves received one of the following treatments under a creep-feeding strategy: mineral mixture only, provided ad libitum (CONTROL); or concentrate supplementation (SUP, 6 g/kg BW, containing 225 g/kg crude protein) with 0% (SUP0), 48.4% (SUP48), or 96.8% (SUP96) DDG inclusion. Concentrate supplementation increased intake of dry matter (DM), crude protein (CP), non-fibrous carbohydrates (NFC), total digestible nutrients (TDN), and the CP/digestible organic matter ratio ( P < 0.10). Digestibility of DM, CP, and NFC decreased linearly with increasing DDG inclusion. Serum glucose, insulin-like growth factor 1, and blood urea nitrogen concentrations were higher in calves on concentrate supplementation ( P < 0.10). Concentrate supplementation increased average daily gain, weaning BW, and ribeye area ( P < 0.10), with no differences related to DDG inclusion ( P > 0.10). Supplementation improves beef calves nutritional characteristics, metabolism and performance. Additionally, DDG can be included in supplements for suckling beef calves grazing tropical pastures, with potential to replace traditional feedstuffs such as corn and soybean meal, without negatively affecting performance and serum metabolism.

The supply of metabolizable nutrients to suckling beef calves on pasture can improve their performance, increasing weaning weight and productivity in cow–calf systems. The objective was to evaluate the effects of dried distillers grains (DDG) inclusion on intake, digestibility, metabolism, and performance of suckling beef calves grazing tropical pastures. Forty-eight Nellore calves, 120 ± 35 days of age and 135 ± 23.4 kg of body weight (BW), were used. Calves received one of the following treatments under a creep-feeding strategy: mineral mixture only, provided ad libitum (CONTROL); or concentrate supplementation (SUP, 6 g/kg BW, containing 225 g/kg crude protein) with 0% (SUP0), 48.4% (SUP48), or 96.8% (SUP96) DDG inclusion. Concentrate supplementation increased intake of dry matter (DM), crude protein (CP), non-fibrous carbohydrates (NFC), total digestible nutrients (TDN), and the CP/digestible organic matter ratio (P < 0.10). Digestibility of DM, CP, and NFC decreased linearly with increasing DDG inclusion. Serum glucose, insulin-like growth factor 1, and blood urea nitrogen concentrations were greater in calves receiving concentrate supplementation (P < 0.10). Concentrate supplementation increased average daily gain, weaning BW, and ribeye area (P < 0.10), with no differences related to DDG inclusion (P > 0.10). DDG can be included in supplements for suckling beef calves grazing tropical pastures, with potential to replace traditional feedstuffs such as corn and soybean meal, without negatively affecting weight gain.