Presentation - Hi Peak Feeds

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The effect of body condition score
change 15 days prior to calving on
lactation curve and production
parameters in grazing dairy cows in
Ireland
M.R. Sheehy*1,2, F.J. Mulligan1, M.A. Crowe1,
S.P.M. Aungier1, and A.G. Fahey3
1School
of Veterinary Medicine, University College Dublin, Ireland
Nutrition Ltd., Belfast, Northern Ireland
3 School of Agriculture & Food Science, University College Dublin, Ireland
2Devenish
Introduction
• The transition period extends from 3 weeks
before to 3 weeks after calving
• It is the most critical period of the lactation
– Nutrition and energy balance
– Production
– Metabolic Health Issues
• Economic and welfare implications
Introduction
OUTPUTS
INPUTS
ENERGY
BALANCE
Energy balance can be assessed during
transition by body condition score change
Previous Studies
Have been concerned with the implications of cows
reaching target BCS at various stages of lactation
Stage
Dry off
Calving
Breeding
150 to 250 days in milk
Body Condition Score
2.75 – 3.00
3.00 – 3.25
Minimum 2.75
2.75 – 3.00
(Mulligan, 2012)
However, little is known about the effect of BCS change
immediately pre-calving on the lactation characteristics of the
dairy cow
Objective
To determine if change in BCS in the last 15 days
before calving has an affect on subsequent
lactation characteristics
Materials and Methods
• Commercial Irish dairy farm
• 98 Spring-calving Holstein-Friesian cows
305 day yields
Milk (kg)
Fat (kg)
Protein (kg)
9125
331
298
Fat (%)
Protein (%)
SCC (‘000 per ml)
3.62
3.27
308
Calving Interval (days)
445
Treatments
MAIN
– cows that maintained BCS 15 d prior to calving
LOSS
– cows that lost BCS 15 d prior to calving
Parity 1
N
∆ BCS
MAIN
23
0
LOSS
8
-0.28
Parity 2
N
∆ BCS
12
0
15
-0.25
Parity 3
N
∆ BCS
20
0
20
-0.32
Body Condition Scoring
• 1 to 5 BCS scale (Edmonson et al., 1989)
• Same trained researcher every 2 weeks
• Eliminate inter-observer variation
Dairy Cow BCS
Body Condition Score (BCS) Records Analysis
Milk Sampling
• Cows milked at 0700 and 1600 h daily
• Milk was sampled every two weeks
– Mid infrared spectrophotometry
– Milk, fat, and protein yields
– Fat, protein, and lactose concentrations
• Energy Corrected Milk (KirchgeBner 1997)
(Milk yield x 0.3246) + (Fat yield x 12.86) + (Prot yield x 7.04)
Lactation Curve Modelling
• Woods Incomplete Gamma Function (Woods, 1967)
• Non-linear function
• y(t) = atbe-ct
–
–
–
–
t = time
a = estimate of initial milk yield
b= rate of increase until peak production
c = rate of decrease after peak production
Curve Shape
Shape
Parameter
Curve Shape description
b
c
C1
+
-
Standard lactation curve
C2
+
+
Continuous increase
C3
-
-
Continuous decrease
C4
-
+
Inverted lactation curve
b
a
c
Lactation Curve Characteristics
• Initial milk yield (a)
• Rate of increase to peak yield (b)
• Rate of decline after peak yield (c)
• Lactation persistency (p)
• Time at which peak yield is attained (Tm)
• Peak yield (Ym)
Statistical Analysis
Yijkl = BCS + Ci + Tj + Pk + TPjk + TCij + PCki+ eijkl
Yijkl = lactation curve characteristics of the lth cow in ith calving month, the jth
treatment, and the kth parity,
BCS = covariate of BCS on d -15
Ci = the ith calving month of Jan, Feb, Mar, or Apr
Tj = the jth treatment of MAIN or LOSS
Pk = the kth parity of 1, 2, or ≥ 3
TPjk = the interaction of the jth treatment and the kth parity
TCij = the interaction of the jth treatment and the ith calving month
PCij = the interaction of the kh parity and the ith calving month
eijkl = random residual error
Results: Milk (kg)
MAIN
Parity 1
Parity 2
LOSS
Parity 3
Parity 1
Parity 2
Significance
Parity 3
T
P
T×P
Milk
a
c
tm
Ym
20.75
22.53
24.54
16.18
17.79
21.04
(2.34)
(2.75)
(2.23)
(3.53)
(2.67)
(2.16)
-0.005Aa
-0.006
-0.006B
-0.007b
-0.006
-0.007
(0.0005)
(0.0004)
(0.0004)
(0.0007)
(0.0005)
(0.0005)
56.24ACc
45.79B
43.51D
48.99d
46.72
44.47
(4.35)
(4.20)
(3.63)
(6.04)
(4.07)
(3.12)
35.82CE
40.33D
46.02F
34.06E
39.77EF
44.36F
(1.21)
(1.42)
(1.24)
(1.74)
(1.31)
(1.06)
<0.05
NS
NS
<0.10
NS
NS
<0.10
NS
NS
NS
<0.01
NS
Results: Fat (kg)
MAIN
LOSS
Significance
Parity 1
Parity 2
Parity 3
Parity 1
Parity 2
Parity 3
6.62a
6.41
6.42
6.15b
6.44
6.33
(0.10)
(0.19)
(0.14)
(0.23)
(0.16)
(0.14)
42.66
45.72
53.38c
40.71
40.70
34.79d
(6.12)
(8.11)
(5.78)
(12.12)
(6.99)
(5.87)
1.11E
1.34F
1.33F
1.25
1.24A
1.37B
(0.04)
(0.06)
(0.04)
(0.09)
(0.05)
(0.05)
T
P
T×P
NS
NS
NS
NS
NS
NS
Fat kg
P
tm
Ym
NS <0.05
NS
305 Day Production Yields
MAIN
Parity 1
Parity 2
LOSS
Parity 3
Parity 1
Parity 2
Significance
Parity 3
Milk
7573.51CE 8352.29DE 9329.21F
6873.65E 8445.86AF 9126.74BF
(kg)
(240.35)
(284.42)
(232.48)
(362.43)
(276.44)
(224.38)
Fat
238.89E
276.53C
330.65DF
248.65
272.14
298.88
(kg)
(16.24)
(20.58)
(16.48)
(25.59)
(19.10)
(16.11)
Prot
238.03E
269.32CF
294.40DF
218.80E
266.03EF
294.21F
(kg)
(6.69)
(7.92)
(6.47)
(10.09)
(7.69)
(6.25)
SCC
108.57A
157.62
252.60aB
164.89C
247.99
369.12bD
(,000)
(63.41)
(58.62)
(48.37)
(88.61)
(59.04)
(45.65)
T
P
T×P
NS
<0.01
NS
NS
<0.01
NS
NS
<0.10
NS
<0.05
<0.05
NS
Summary
• Overall
–
–
–
–
MAIN significantly greater initial milk yield (a) than LOSS
MAIN significantly lower SCC than loss
LOSS cows tended to reach peak milk yield sooner
LOSS cows tended to have a faster rate of decline post peak
• Parity 1
– MAIN took longer to reach peak milk yield
– MAIN lower rate of decline post peak milk yield
– MAIN more persistent fat yield curve
• Parity 3
– MAIN took longer to reach peak fat yield
– MAIN had lower somatic cell count
Conclusion
• Ideal lactation curve
– Cows that reach peak milk and component yields
slowly and remain persistent
– More beneficial to the cows’ metabolic and health
status (Solkner and Funchs, 1987)
• Therefore MAIN parity 1 and parity 3 cows
had improved lactation curve characteristics
compared to LOSS parity 1 and parity 3
Thank you for your attention
The effect of body condition score
change 15 days prior to calving on
lactation curve and production
parameters in grazing dairy cows in
Ireland
M.R. Sheehy*1,2, F.J. Mulligan1, M.A. Crowe1,
S.P.M. Aungier1, and A.G. Fahey3
1School
of Veterinary Medicine, University College Dublin, Ireland
Nutrition Ltd., Belfast, Northern Ireland
3 School of Agriculture & Food Science, University College Dublin, Ireland
2Devenish
Lactation Curve Characteristics
• Initial milk yield (a)
• Rate of increase to peak yield (b)
• Rate of decline after peak yield (c)
• Lactation persistency (p)
– p = -(b+1)*ln(c)
• Time at which peak yield is attained (Tm)
– Tm =b/c
• Peak yield (Ym)
– Ym = a(b/c)be-b
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