Davlea Bradnick Alicia

Lifetime Performance Index (LPI) Formula

Where the relative emphasis placed on each of the three main components in each breed is presented in the following table along with the multiplicative factors for each component.

LPIformulaEng1

 

LPIformulaEng2

Production Component (PROD):
PROD = [WPYx(PY-AvgPY)/SDPY] + [WPDxPD/SDPD] + [WFYx(FY-AvgFY)/SDFY] + [WFDxFD/SDFD]

Where PY = Protein Yield, PD = Protein Deviation, FY = Fat Yield and FD = Fat Deviation, which are standardized using the appropriate averages (Avg) and standard deviations (SD) and then multiplied by their respective relative weight (W), all of which are breed specific as outlined in the following table.

LPIformulaEng3

Durability Component (DUR):

DUR = [WHL x (HL – 100)/5] + [WMS x MS/5] + [WF&L x F&L/5] + [WDS x DS/5] + [WRP x RP/5]

Where HL = Herd Life, MS = Mammary System, F&L = Feet and Legs, DS = Dairy Strength and RP = Rump, and each trait is standardized using the appropriate averages and standard deviations and then multiplied by their respective relative weight (W) that is breed specific as outlined in the following table.

LPIformulaEng4

Health & Fertility Component (H&F):

H&F = [WDF x (DF-100)/5] + [WMR x (MR-100)/5] +
[WSCS x -1 x (SCS-3.00)/0.23] + [WUD x UD/5] + [WMSP x (MSP-100)/5] + [WLP x (LP-100)/5]

Where DF = Daughter Fertility, MR = Mastitis Resistance, SCS = Somatic Cell Score, UD = Udder Depth, MSP = Milking Speed and LP = Lactation Persistency.  The relative weights for each trait (i.e.: WDF, WMR, WSCS, WUD, WMSP and WLP respectively), which are specific to each breed, are provided in the following table.

LPIformulaEng5

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Previous LPI update documents:

April 2017
April 2016
August 2015
April 2015
April 2014
April 2013
April 2012
April 2011
January 2010
January 2009
January 2008
February 2007

 

Source: Canadian Dairy Network

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Davlea Bradnick Alicia

Lifetime Performance Index (LPI) Formula

Where the relative emphasis placed on each of the three main components in each breed is presented in the following table along with the multiplicative factors for each component. …

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