INTENSIFIED COW/CALF PRODUCTION IN THE SOUTHERN GREAT PLAINS Adam McGee, Jarrod Cole, Corbit Bayliff, Miles Redden, Courtney Spencer, Jason Warren, Damona Doye, Ryan Reuter, Gerald Horn, and David Lalman 1
Introduction Increasing population 8.5 billion people by 2030 Grazing land disappearing Urban encroachment Competition for other Ag use Challenge Feed increasing population Fewer resources Photo Courtesy of Oklahoma State University 2
Introduction 2014 5.3 Million acres of wheat planted Oklahoma Ag Statistics 2015 Estimated 61% of wheat used for Forage only or Dual purpose wheat Hossain et al 2004 Photo Courtesy of Oklahoma State University 3
Introduction Grazing Wheat Common practice in Southern Plains Typically used with stockers Cow/calf pairs Not very common Waste of nutrients Photo Courtesy of Oklahoma State University 4
Objectives Photo Courtesy of Oklahoma State University Develop a management system utilizing semi confinement and limit grazing of wheat and summer annuals to: Match fall calving cow nutrient requirements during strategic times of the year Reduce land area required for cow-calf production Economically feasible 5
Hypothesis Cattle allowed to limit graze wheat during the winter and summer annuals during the summer will maintain a consistent BCS through the year and wean heavier calves while utilizing fewer hectares of land. 6
Mcal/d 25 Fall Calving Cows Nutrient Requirements Net Energy Mcal/d Weaning Calving 20 15 10 5 0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Required Range Range and Protein Supp NRC, 1996 7
Mcal/d 25 Fall Calving Cows Nutrient Requirements Net Energy Mcal/d Weaning Calving 20 15 10 5 0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Required Range Range and Protein Supp NRC, 1996 8
Materials and Methods Cattle Performance Multi Year Systems study Cow/Calf Stocker Feedlot Photo Courtesy of Oklahoma State University Photo Courtesy of Oklahoma State University Photo Courtesy of Dr. David Lalman 9
Materials and Methods Treatments Intensive INT Extensive EXT 3 replications/trt Cattle remain in treatment for duration Age Reproductive failure Photo Courtesy of Oklahoma State University 10
Materials and Methods Cattle Performance Angus/Hereford Mature Cows Fall Calving Calving Sept-Oct Implant May Wean Mid June-July Photo Courtesy of Oklahoma State University 11
Materials and Methods Cattle Performance Fixed Timed AI 7 day Co-Sync + CIDR Charolais Cleanup Bulls 45 days Comingled Prior to burning Weaning Calving Photo Courtesy of Oklahoma State University 12
Materials and Methods Statistical Methods One Way Design Fixed Effect: Treatment Random Effect: Year Pasture within Treatment SAS 9.3 (SAS Institute Inc, Cary, NC) Glimmix procedure Significance level if P < 0.05 13
Materials and Methods EXT Treatment 14 hd/rep Native range Continuously stocked 13.41 ac/cow-calf pair Little additional forage Protein supplement October- March 2.49 lb/hd/day 38% protein cube Photo Courtesy of Oklahoma State University 14
Materials and Methods INT Treatment 18 hd/rep Forages 7.24 ac/cow-calf pair Native Wheat Summer annual Supplements Protein only from Oct.-Nov. 1.5 lbs/hd/day Photo Courtesy of Oklahoma State University 15
Materials and Methods INT Treatment Grazing Period Dates Days Feed/Forage ha/cow Winter Dec-March 103-120 Dry Lot Limit Graze Wheat 0.74 Spring Graze-out March May 23-41 Ad Lib Wheat 0.74 Early Summer May July 30-69 Native Rangeland 6.50 Late Summer July- August 30-48 Summer Annual 0.50 Fall Sept-Dec 102-112 Native Rangeland 6.50 Total Land Area 7.24 16
Materials and Methods INT Treatment During Winter Grazing Period Ad Lib Hay Native Prairie hay Wheat, sorghum sudan, or crabgrass hay from previous year Grazed 3hr/day, 3 days/wk Calves allowed ad lib access 17
Materials and Methods Wheat DMI 2 cows/pen Weighed Grazed Fecal collected Calf prevented from nursing Weighed (Final-Initial) + Fecal*Wheat DM Photo Courtesy of Oklahoma State University 18
Materials and Methods Summer Annuals Year Cows Stockers 1 BMR Sorghum sudan, sunhemp, and cowpeas BMR Sorghum sudan, sunhemp, and cowpeas 2 Bermuda Grass Red River Crab Grass 3 Red River Crabgrass- Limit grazed 3 hr/day Native Range 19
Materials and Methods Hay Production Hay baled only on INT Wheat Crabgrass Sorghum sudan/sunhemp/cowpeas Remainder of hay purchased 20
Materials and Methods Stocker phase Weaning to feedlot entry Mid June Mid August 60 days Additional animals added in Year 2 Year EXT INT 1 Native Range BMR Sudangrass Mix 2 Native Range Red River crabgrass 3 Native Range Native Range 21
Body Wt, lb Cow Body Weight 1600.0 1400.0 1200.0 P = 0.13 P < 0.01 P < 0.01 P < 0.01 P = 0.36 1000.0 800.0 600.0 400.0 200.0 0.0 Initial Winter Spring Graze-out Early Summer Late Summer EXT INT 22
Body Condition Score Cow BCS 9 8 7 6 5 4 3 2 1 0 P < 0.03 P < 0.91 P < 0.01 P = 0.84 P < 0.01 Initial Winter Spring Grazeout Early Summer Late Summer EXT INT 23
Reproductive Performance 100% 90% 88% 91% 80% 70% 65% 60% 50% 49% 40% 30% 20% 10% 0% Pregnancy Rate % AI Sired Calves P = 0.54 EXT INT P = 0.11 24
Body Wt, lb Calf Weight 900.0 800.0 700.0 P < 0.01 P = 0.04 P = 0.02 600.0 P < 0.01 500.0 P = 0.91 400.0 300.0 200.0 100.0 0.0 Initial Winter Grazeout Early Summer Late Summer EXT INT 25
ADG, lb Calf ADG 4.00 3.50 3.00 2.50 2.00 1.50 1.00 0.50 P < 0.01 P = 0.02 P = 0.01 0.00 Winter Spring Grazeout Early Summer EXT INT 26
% Body weight Wheat DMI 1.6 1.4 1.2 1.25 1.49 18.39 lb 1 0.8 0.6 0.4 0.2 0 0.94 11.60 lb January February March 27
ADG, lb Stocker ADG 2 1.78 1.5 1 1.26 1.05 1.15 1.22 0.97 0.5 0 Year 1 Year 2 Year 3 EXT INT Year EXT INT 1 Native Range BMR Sudangrass Mix 2 Native Range Red River Crabgrass 3 Native Range Native Range 28
Hay Production Year Forage East Pen Center Pen West Pen 1 BMR Sudan Grass Early 4.49 3.90 4.69 1 BMR Sudan Grass Late 7.84 8.16 6.85 2 None baled 3 Wheat 5.51 4.34 2.80 3 Crabgrass 2.94 3.21 2.83 29
Summary Cows INT heavier and greater BCS at all time points except initial and late summer No difference in pregnancy rate Trend towards more AI sired calves in EXT treatment Photo Courtesy of Oklahoma State University 30
Summary Calves INT were heavier throughout the year ADG was statistically significant at all time points INT greater during Winter and Grazeout EXT greater during early summer Reduced land mass 13.41 ac EXT 7.24 ac INT 54% Reduction in land use 31
Questions Photo Courtesy of Oklahoma State University 32