01968naa a2200217 a 450000100080000000500110000800800410001910000180006024500730007826000090015130000140016052012640017465000270143865300210146565300220148665300190150865300460152770000180157370000170159177301420160810045512011-03-28       1992    bl uuuu     u00u1 u    #d1 aOLTJEN, J. W.  aDynamic allocation of multiple forage sources for beef cattle herds.  c1992  ap. 59-63.  aMatching beef herd requirements with feed resources over time increases in complexity with the number of forage types. We developed a spreadsheet to calculate animal requirements through time and show how available forages might meet herd needs. This identifies periods when animal requirements exceed forage availability. Weekly intervals were used to specify animal requirements and forage availability. Animal classes and initial weights, frame sizes, target gains, pregnancy rate, weaning rate, and dates of calving and weaning are input. Animal weights, stage of gestation and lactation, breeding period and metabolizable energy (ME) requirements are estimated weekly. Up to 15 typical forage sources are input with expected dates available for grazing and yields. Supplement needs are the difference between weekly ME requirements and yields from grazing converted to ME. Results are shown by spreadsheet associated graphs depicting ME needs by animal class, ME available by forage type, excess forage ME available or supplement needs over time. Costs can be compared for different input values and, in particular, for alternative dates of calving and/or weaning. As a longer-term planning tool, more optimal mixes of forage resources can be identified.  aInformation technology  aAgroinformática  aBeef cattle herds  aForage sources  aTecnologia de informação na agricultura1 aGEORGE, M. R.1 aDRAKE, D. J.  tIn: INTERNATIONAL CONFERENCE, 4., 1992, Orlando. Computers in agricultural extension programs: Proceedings... St. Joseph, MI: ASAE, 1992.