title: Performance of Angus and Brangus cow-calf pairs grazing Alicia bermudagrass and common bermudagrass-dallisgrass pastures.
abstract: This research was designed to examine genotype x environment interactions in cow-calf growth performance of grazing animals. Angus and Brangus cow-calf pairs (minimum of six per breed) were allowed to rotationally graze (14-d intervals) treatment pastures from approximately May through early October in each of 2 yr. Treatment pastures contained relatively pure stands of Alicia bermudagrass (AP) or a mixed stand of common bermudagrass and dallisgrass (CDP). Forage allowance was equalized, using "put-and-take" cow-calf pairs, among forage and breed types at the initiation of each 14-d grazing interval. Forage samples were obtained in each paddock at the initiation of each grazing interval. Forage CP concentration was greater (P < .05; 13.5 vs 11.6%) and NDF concentration was less (P < .05; 63.8 vs 70.6%) for CDP than for AP. Daily weight loss was similar for Angus and Brangus cows, but it was greater (P < .05) for cows grazing AP than for cows grazing CDP. Calf ADG during the grazing season was 35% greater (P < .05) for CDP than for AP pastures and was 23% greater (P < .01) for Brangus than for Angus calves. Relative performance of Angus and Brangus cow-calf pairs was consistent between forages; no breed x forage interactions were observed.
authors.affiliation: Louisiana Agricultural Experiment Station, Louisiana State University Agricultural Center, Baton, Rouge 70803, USA.
authors.forename: W E
authors.initials: WE
authors.lastname: Wyatt
authors.forename: R N
authors.initials: RN
authors.lastname: Gates
authors.forename: D C
authors.initials: DC
authors.lastname: Blouin
authors.forename: A M
authors.initials: AM
authors.lastname: Saxton
authors.forename: B D
authors.initials: BD
authors.lastname: Nelson
mesh_terms: D000821:Animal Feed / Q000592:standards*; D000818:Animals; D001835:Body Weight / Q000502:physiology; D001947:Breeding; D002417:Cattle / Q000235:genetics* / Q000254:growth & development* / Q000502:physiology; D004777:Environment; D005260:Female; D008297:Male; D006109:Poaceae; D011897:Random Allocation; D012621:Seasons; D015430:Weight Gain / Q000502:physiology