Determining Forage Intake of Nursing Calves Grazing Native Sandhills Rangeland

The objective of this study was to determine nursing calf forage intake prior to weaning in the Nebraska Sandhills range. Eight crossbred cow-calf pairs in year one and 12 pairs in year two were selected for each trial. Pairs were randomly assigned to one of two rotation groups, pasture (Graze) or individual fed dry lot pens for each pair (Pen). Pen pairs were fed harvested meadow hay of similar quality to forage grazed in Graze daily. Cattle were adapted for two weeks and had one week of collection per period before switched to the other rotation. Groups were switched back and forth between Pen and Graze from June until mid-October. Diet samples were collected each period in pasture assigned to study. Total fecal collection for calves was conducted consecutively for five days and subsampled daily for analysis each period. Feed and diet samples were analyzed for DM, OM, CP, IVOMD, NDF, and indigestible ADF. Milk production was measured using weigh-suckle-weigh techniques each period. Calf organic matter intake (OMI) increased for both Pen and Graze in Year 2 from periods 1-6 for kg per day intake 0.99 to 3.04 and 1.47 to 3.17, respectively. Intakes increased as well as a percent of BW from periods 1-5 for Pen going from 0.89-1.55% and decreasing to 1.42% for period 6 and Graze rising from 1.33-1.68% for periods 1-5 and decreasing to 1.43% in period 6. There was no significant difference between calf OMI for Pen and Graze groups (P>.10) for either kg per day or as a percent of BW. In Year 1 milk production decreased over time from 7.5 to 4.0 kg/d and Year 2 milk production was fairly constant at an average 4.0 kg/d. Calf forage intake increased over time until weaning in the fall and range managers would be advised to include calf forage intake in pasture management and stocking rate decisions throughout grazing season.