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Transition Cow Index®. Ken Nordlund , DVM University of Wisconsin-Madison. Transition period ~3 weeks before and after calving High risk period during which ~75% of dairy cow disease occurs. Topics. Reproduction vs milk production Transition Cow Index®
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Transition Cow Index® Ken Nordlund, DVM University of Wisconsin-Madison
Transition period ~3 weeks before and after calving High risk period during which ~75% of dairy cow disease occurs
Topics • Reproduction vs milk production • Transition Cow Index® • TCI® and associated milk yield, survival, and reproduction • Management factors associated with TCI • Summary
Reproduction vsmilk yield • Antagonistic • At herd level, high production herds achieve better reproductive performance • At the cow level….
Milk Yield and Probability of Pregnancy by 150 DIM 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 The likelihood of pregnancy by 150 DIM decreases 1.2% for every 1,000 lb increase in milk. Likelihood of Pregnancy by 150 DIM Data from 68,255 cows in 2,236 herds 0 10,000 20,000 30,000 40,000 50,000 60,000 Lbs of Milk in Current Lactation
Topics • Reproduction vs milk production • Transition Cow IndexTM • TCI and associated milk yield, survival, and reproduction • Management factors associated with TCI • Summary
AgSource DHIA data for 2 consecutive years from half-million cows Matched 4,000 herds with Posilac purchase records over 2 years Used “historical” data in mixed model to calculate expected 1st test milk and 1st test projection TCI = difference between expected and actual 1st test 305-day projected milk for individual cow Transition Cow Index®
Factors used in TCI® equations • Days in milk at first test • Previous 305-day milk • Days in milk in prior lactation • Start of current lactation as calving or abortion • Start of prior lactation as calving or abortion • Month of calving • SCC log score at last test of prior lactation • Days dry • Milking frequency current lactation • Milking frequency prior lactation • Parity number • Breed • Posilac use at herd level
+ TCI - TCI 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 10 10 11 11 12 12 Transition Cow Index®(TCI) Prior milk Abort? Prior SCC Days dry 3X Breed Calving month Etc. Posilac
Does TCI® reflect disease? • Collected DC305 records from 110 herds in Jan 2010 with recorded disease events • Selected herds with minimal recorded incidence ≥1% in first 40 days in milk of: • Retained placenta or metritis • Ketosis • Displaced abomasum • Mastitis • 31 herds met criteria with overall average TCI = +63 lbs
Topics • Reproduction vs milk production • Transition Cow IndexTM • TCI and associated milk yield, survival, and reproduction • Management factors associated with TCI • Summary
20,000 lbs TCI associated with 48% increased survival rate(2.4% per 1,000 lbs) TCI vs. Survival to Next Lactation 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 Probability of Survival to Next Lactation Records of 194,402 cows in 4,025 herds -20,000 -10,000 0 10,000 20,000 TCI
TCI vs Milk Production 110,000 100,000 90,000 80,000 70,000 60,000 50,000 40,000 30,000 20,000 10,000 0 -20,000 -10,000 0 10,000 20,000 TCI 1 lb TCI associated with 1.27 lbs milk in subsequent lactation 1 lb TCI associated with 1.3 lbs cumulative milk Cumulative lbs milk, current lactation Data from 194,402 cows in 4,025 herds
TCI vs. Likelihood of Pregnancy by 150 DIM 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 Over 20,000 lbs TCI, the likelihood of pregnancy by 150 DIM increases 5%(0.25% per 1000 lbs TCI) Likelihood of Pregnancy by 150 DIM Data from 68,255 cows in 2,236 herds -20,000 -10,000 0 10,000 20,000 TCI
Production & reproduction with TCI • 1,000 lb of TCI is associated with 1,300 lbs additional milk • 1,300 lb milk would usually be associated with a reduced likelihood of pregnancy at 150DIM of 1.5% • If achieved through improved transition management, reproductive performance improves slightly
Topics • Reproduction vs milk production • Transition Cow IndexTM • TCI and associated milk yield, survival, and reproduction • Management factors associated with TCI • Summary
What are the primary factors? • Transition management practices of 45 larger Wisconsin freestall herds evaluated in summer of 2005 • Stratified random selection representing range in annual herd average TCI score from -3,000 to +3,000 lb • Herd average size ~600 cows (range 300 – 1,600)
Example herd – 1 year TCI scores Annual average (-)142 lbs
Annual herd TCI average (-) 142 lbs
Wisconsin Freestall Study • Bunk space for all transition cows to eat simultaneously • 30 inches (76 cm) of bunk space per cow • Sand-based freestalls • Larger sized freestalls • Screening for sick cows based on appetite and attitude • Minimize regroupings • No social regroupings 3-10 days before calving
Ration nutrients vs. Herd avg. TCI Pre-fresh ration %NDF
Bunk space was the single most important risk factor for TCI Cows will fill standard 24” headlocks to a maximum of 80% under normal circumstances
Bunk space • Cows are allelomimetic animals • If can’t eat together, cows that eat later eat less • If eat less, ↑ risk of fresh cow disease • ~30 inches per cow needed to eat simultaneously • Build prefresh pens to provide 30 inches bunk space even when cow numbers surge
Freestall Factors • Stall surface (ls means) • Mattress barns (-) 675 lbs TCI • Sand barns (+) 560 lbs TCI Dimensions (width x length including available forward lunge)
45” 66” • Too small for modern mature Holstein cows! • Okay for 1st lactation cows • Dimensions originated in the 70’s • Cows have gotten bigger • Understanding of ergonomics has improved
Maternity or calving pens Movement into calving pens 3-10 days prior to due date associated with lower TCI than movement ≤2 days
Optimal transition barns • 30” bunk space per cow • Deep, soft bedded surfaces • Sand-based freestalls • Deep bedded packs • If freestalls, >48” wide & >9 ft long (Holsteins) • Stable social groups – • Fix the cohort groups at dry-off if possible • Build capacity for 130-140% of average • Avoid overstocking EVEN during surges of #
Traditional method of pen sizing • Example: 1,600 cow herd • How many calvings per week? • 7 days in a week divided by 365 days equals 1.9% • 1.9% of 1,600 cows equals 31 cows per week • How long is close-up period? 3 weeks! • 3 wk x 31 cows/wk = 93 stalls
Average = 28 per week Range = 15 to 40 (54%-143% of avg) Guideline: “Overbuild” for surges 3-wk period:130-140% of wkavg
Fundamental point for transition cow management • These recommendations apply to the pre-fresh and postfreshperiods, not the entire herd • Each prefreshstall gets used for a period of 3-7 weeks • Each prefreshstall is a factor in determining the success of not one, but 7 to 15 cows per year!
Let’s rethink this! • Conventional wisdom: The most expensive thing on a dairy is an empty stall • NONSENSE! • The most expensive thing on a dairy is a PREFRESH stall that is always full!
Topics • Reproduction vs milk production • Transition Cow Index® • TCI and associated milk yield, survival, and reproduction • Management factors associated with TCI • Summary
+530 +1,988 A gain of 1,450 lbs TCI®!
Impact of TCI gain of 1,400 lbs • Reduction in fresh cow disease, drug use, labor • Survival rate to next lactation ↑ 3.5% • Milk yield ↑ 1,800 lbs per cow • Likelihood of pregnancy by 150 days in milk ↑ 0.3% • rather than decreasing by ~2% if production were achieved using traditional methods of nutrition or others
Summary • TCI offers an objective measure of herd-level fresh cow health • Field surveys show “cow comfort” issues of bunk space, minimizing lameness, cushioned surfaces, and larger freestalls to be key risk factors for transition cows • Improved transition management will increase milk yield and longevity, without reducing reproductive performance
Availability of TCI • Patented in USA by University of Wisconsin, application in European Union • Licensed to AgSource in 2006, the DHIA service based in Wisconsin • Interested groups should contact AgSource • Sublicensed to Valacta, the DHIA service based in Quebec • Sublicensed to Pfizer USA