Read Albert de Vries - Productive life of dairy cows in Florida (FLDPC2003).ppt text version

Productive Life of Dairy Cows in Florida

Albert de Vries

Department of Animal Sciences University of Florida

Overview

n n

Synonyms, measures Some factors that affect productive life

n n

Literature Florida/Georgia data

n

Economic value of productive life

Synonyms

n

Productive life ~ longevity ~ herd life ~ survivability ~ stayability ~ lifespan ~ durability "How long cows stay in the herd"

n

Measures of productive life

n n n n n

Age Number of parities Lifetime production % not culled by certain time Total months in milk at 84 months of age (USDA)

n n

Maximum 10 months per lactation (305 days) Dry months not counted

n

Time between first calving and culling

Relationship "productive life" ~ cull rate

n

Average productive life (days) = 1 / cull rate * 365 Example, cull rate is 35% (0.35): Average productive life (days) = 1 / 0.35 * 365 = 1043 days = 34.3 months = 2.86 years

n

Some factors that affect productive life

Productive life depends on cow and human factors

n

Cow: good production, health, reproduction, free from injury and udder problems, workable temperament

à drives involuntary culling

n

Human: economic culling decision

à drives voluntary culling

Culling reasons

USA (1987)* Florida (2002)** Sold ­ dairy Sold ­ low production Sold ­ reproduction Sold ­ disease, injury Sold ­ mastitis, udder Died Sold - feed and legs 14% 42% 10% 20% 9% 5% 8% 12% 19% 18% 14% 22% 8%

*Dentine et al, JDS 70:2616 **Florida Herd Summary DHI-202 State Average

Stayability

n

True stayability: ability to avoid culling

n n n

USDA Productive Life (PL) Includes milk yield information High correlation with milk production

n

Functional stayability: ability to avoid involuntary culling

n n

Excludes milk yield information Canadian Herd Life (HL)

VanRaden and Wiggans, 1995 JDS 78:635

Genetic effects

n

2 general methods to evaluate cattle for longevity:

n n

Indirect: yield traits, type traits Direct: Productive life

Breed and crossbred differences

n n

Average PL for Holsteins: 23.8 months Jerseys, Jersey x Holstein, Brown Swiss x Holstein: less than 1 month longer than Holsteins

VanRaden, 1995 JDS 78(suppl1):159

Survival in crossbreds compared to herd mates (survey)

Breed/cross (Sire x Dam) Holstein x Holstein Brown Swiss x Holstein Jersey x Jersey Jersey x Holstein Jersey x (Jersey x Holstein) Score (1 = poor, 5 = excellent) 2.6 3.1 3.3 3.6 4.2

Weigel and Barlass, Hoard's Dairyman (March 25, 2003)

Inbreeding in Holsteins

1% increase in inbreeding à - 6 days of productive life

Smith et al. 1998 JDS 81:2729

Housing

· 186 WI expanded dairy herds 1994 ­ 1998 Risk of culling vs. average cow Low cows Fans No 2.52 Yes 2.60 Sprinklers No 2.52 Yes 2.67 Free stall bedding Mattress 2.32* Sand 2.60*

* Significant effect P < 0.05

High cows 0.76* 0.67* 0.72* 0.63* 0.69 0.68

Weigel et al. 2003 JDS 86:1482

Florida study

n n

2 DHIA data sets (DRMS, Raleigh, NC) 41,369 first calvings in 1995 and 1996

n n n

100 Florida dairy herds 37,587 (91%) culled 3,782 ( 9%) censored (cull date not known) 109 Florida + 235 Georgia dairy herds

n

52,622 cows culled in 2000 and 2001

n

n

Herd summary 202 data for all herds

Survival curve

100%

% Cows still in herd (all Florida cows)

80% 60% 40% 20% 0% 0 210

Median = 827 days

420

630

840

1050

1260

1470

1680

1890

Productive Life (Days)

2100

Chance of being culled per day (hazard)

(all Florida cows) Chance of being culled / day

0.005 0.004 0.003 0.002 0.001 0.000 210 420 630 840 1050 1260 1470 1680 1890 2100 0

Productive Life (Days)

% cows leaving per day in milk of all cows that left in the lactation 0.6% 0.5% 0.4% 0.3% 0.2% 0.1% 0.0% 0

(All Florida data)

100 200 300 400 500 600 700 800

Days in milk

% cows leaving per day in milk of all cows left in the lactation (4 reasons) Repro problems Death Mastitis Low production

0.4% 0.3% 0.2% 0.1% 0.0% 0

100 200 300 400 500 600 700 800

Days in Milk

Differences in productive life (days) by month of first calving 100 FL + GA data 50 0

Days

-50 -100 -150 -200 Jun May Aug Feb Sep Nov Jan Jul Mar Apr Oct Dec

Average Median

Month of first calving

Differences in average lifetime milk / day (lbs) by month of first calving

FL + GA data

4 3 2 1 0 -1 -2 -3 -4 -5 Jan

Milk / day (lbs)

Average

May

Aug

Feb

Sep

Nov

Jun

Jul

Mar

Apr

Oct

Month of first calving

Dec

Productive life and average lifetime milk / day by average herd size (# cows)

Productive Life (days) 200 150 100 Days 50 0 -50 -100 -150

<100 #herds 38 100250 111 250500 52 5001000 38 1000- >1500 1500 13 6

Milk / day (lbs) 2.0 1.5 1.0 0.5 Lbs

1

2

3

4

5

6

0.0 -0.5 -1.0

Productive life and average lifetime milk / day by average herd SCC (x 1000)

Productive Life (days) 60 40 Days 20 0 1 2 3 4 5 -2 -4

<300 #herds 28 300-400 43 400-500 55 500-600 26 >600 20

Milk / day (lbs) 4 2 0 Lbs

-20 -40 -60

Productive life and average lifetime milk / day by average standardized 150 day milk

Productive Life (days) 100 50 Days 0 1 -50 -100

<55 #herds 39 55-60 52 60-65 55 65-70 52 >70 60

Milk / day (lbs) 10 5 0 Lbs

2

3

4

5 -5 -10

% cows culled in first lactation and average milk / day of culled cows, by month of first calving

% culled in 1st lactation 50% 40% 30% 20% 10% 0% Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Milk / day (lbs) 50 40 20 10 0 Lbs 30

Month of first calving

Economic value of productive life

Value of productive life: with and without opportunity cost

Example: Cost of heifer: $1500 Cull value: $350 Returns minus cost per lactation: Lact. $ 1 2 3 460 4 400 5 290 6 170 7 -10 8 -90

420 480

Cost of heifer: $1500, Cull value: $350, Returns ­ cost per lact: Lact. $ 1 2 3 460 4 400 5 290 6 170 Total -730 -250 210 610 900 1070 1060 970 7 -10 8 -90

420 480

Lactations kept 1 -1500 + 420 + 350 = 2 -1500 + 420 + 480 + 350 = 3 -1500 + 420 + 480 + 460 + 350 = 4 -1500 + 420 + .. + 400 + 350 = 5 -1500 + 420 + .. + 290 + 350 = 6 -1500 + 420 + .. + 170 + 350 = 7 -1500 + 420 + .. - 10 + 350 = 8 -1500 + 420 + .. - 90 + 350 =

Avg. / lact -730 -125 70 153 180 178 151 121

Value of productive life

n

$28 / mo (USDA PTA Productive Life) $29 / mo (considers opportunity cost) $70 / mo (without opportunity cost)

(Jagannatha et al. 1998 JDS 81:1702)

n n

n

Value in Florida?

Acknowledgments

n n

Milk Check-off Dairy Records Management Systems (Raleigh, NC)

Information

Albert de Vries - Productive life of dairy cows in Florida (FLDPC2003).ppt

32 pages

Report File (DMCA)

Our content is added by our users. We aim to remove reported files within 1 working day. Please use this link to notify us:

Report this file as copyright or inappropriate

1166386


You might also be interested in

BETA
2003 DPC Proceeding.doc