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Factors that impact longevity of Holsteins in the
United States
  • H. D. NORMAN and J. R. WRIGHT
  • Animal Improvement Programs Laboratory
  • Agricultural Research Service, USDA
  • Beltsville, MD 20705-2350
  • dnorman@aipl.arsusda.gov
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Previous Findings
  • An overview of the survival rate to various parities and herd life by breed and year was reported previously.
  • Hare, E., Norman, H.D., Wright, J.R. “Survival rates and herdlife of dairy cattle in the United States”.   J. Dairy Sci. (accepted)
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Mean number of parities
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In-progress Report
  • A recent study shows how producers value yield and fitness traits when culling cows.
  • Norman, H.D., Hutchinson, J.L., Kuhn, M.T., Wright, J.R., Lawlor, T.J. “Selection on yield and fitness traits when culling Holsteins during the first three lactations”.  J. Dairy Sci. (submitted)


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Emphasis given to traits when culling during 1st lactation compared to milk
  •                  Relative emphasis on trait
  •             Milk     Fat   Protein           Days Dystocia Final
  • Year     yield   yield   yield    SCS    open  score    score
  • 1984    100       83      97        --    -21      -9         29
  • 1988 100       82      99      -19      -18      -8         26
  • 1992    100       76    101      -25      -23      -9         24
  • 1996    100    74    100      -26      -30      -9         23
  • 1997    100    83      91      -31      -61     -11        33
  • 2000    100       78      95      -33      -74     -15        33


  • From: Norman et.al., J. Dairy Sci. (submitted)
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Current Objective

  • To examine some additional factors to determine how they impact herd life in Holsteins.


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Data edits
  • Herd participated in DHI testing for 1 year prior to cow’s first calving and remaining on test throughout the cow’s lactations
  • Cows first calving 1980 to 1995 and remaining in same herd
  • Cows culled for dairy purposes excluded
  • No missing lactations (required 270–650 days between lactations)
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Mean parities by region
  •                                              Region


  •   Mid-    Mid-     Mtn.-   North-  North-   South-  South-
  • Year      east     west    Prairie    east      west      east      west


  • 1980     3.24     3.09      3.03      3.43      3.23      3.14      3.22
  • 1984     3.03     2.91      2.95      3.23      3.04      3.01      3.14
  • 1988     2.90     2.74      2.81      3.06      2.91      2.82      2.97
  • 1992     2.80     2.71      2.78      2.95      2.83      2.67      2.90
  • 1995     2.72     2.67      2.69      2.92      2.82      2.58      2.85


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Mean parities by herd size
  • Cows in herd (no.)
  •                        51–     101–   201–   501–  1001–   2001–
  • Year    5–50    100     200     500    1000   2000    5000
  • 1985    3.05    3.02    2.99    3.03    3.02    2.87     2.82
  • 1987    2.95    2.94    2.92    2.95    2.96    2.86     2.60       1989    2.85    2.85    2.85    2.92    2.88    2.84     2.73
  • 1991    2.83    2.82    2.82    2.85    2.89    2.80     2.64
  • 1993    2.82    2.79    2.77    2.80    2.89    2.81     2.77
  • 1995    2.81    2.78    2.73    2.77    2.81    2.75     2.71
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Mean parities by level of inbreeding
  •                         Inbreeding coefficient (%)


  • 0.1-    1.1-    2.1-   3.1-    4.1-    5.1-    7.1-   10.1
  • Year        0       1.0      2.0     3.0     4.0     5.0     7.0   10.0   15.0   >15.0


  • 1980     3.33   3.14   3.26   3.31   3.24   3.13   3.09   2.98   2.88   2.91
  • 1984     3.15   3.04   3.02   3.00   2.96   2.98   2.90   2.87   2.74   2.78
  • 1988     2.98   2.91   2.86   2.84   2.82   2.81   2.79   2.74   2.59   2.60
  • 1992     2.96   2.89   2.82   2.79   2.80   2.80   2.73   2.65   2.55   2.61
  • 1995     3.02   2.92   2.83   2.76   2.74   2.76   2.70   2.64   2.60   2.49


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Edits for analysis of terminal lactations
  • Only data from Dairy Records Processing Centers reporting complete data (DIM >305)


  • Cows culled for dairy purposes excluded


  • Cows exiting herds during 2002-2005
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Lactation length of exiting cows  (2002-2005)
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Lactation length of exiting cows for 3 parities (2002-2005)
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Probability of exiting cows leaving by lactation length (2002-2005)
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Probability of exiting cows leaving by lactation length for 3 parities (2002-2005)
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USDA termination codes (%) for Holstein cows exiting herds (2002-2005)
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USDA termination codes (%) for Holstein cows exiting herds by parity (2002-2005)
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Mean DIM for cows exiting herd by USDA termination code (2002-2005)
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Conclusions
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Conclusions
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Conclusions