Effects of Parity, Calving Season and Diseases on Lactation Curve of Vrindavani Cattle

1
.
International Conference on Statistics Big
Data Bioinformatics in Agricultural
Research21st -23rd November 2016

Effect of Parity, Calving Season and Diseases on
Modelling of Lactation Curves of Vrindavani Cattle
Shashank Kshandakar,Med Ram Verma, Yash Pal
Singh and Sanjay KumarICAR-Indian Veterinary
Research Institute, Izatnagar
2
19th Livestock census 2012, Ministry of
Agriculture
3
Introduction

• Share of Agriculture and Livestock Sector in GDP
  is 17.1 and 4.1 respectively. Dairy sector
  contributes 66.5 of the total contribution from
  animal husbandry sector
• (The Economic Survey, 2014-15)
• Per Capita availability of milk in India is 322
  (gram/day)
• The dairy industry in India is currently
  estimated to be about 146.3 million tonnes and is
  expected to grow at 4 per annum 
• (DAHDF, Ministry of Agriculture, GoI)
• The Government dairies and cooperatives, Private
  sector and Organised dairies account 10, 20 and
  30 respectively (approx.)

4
Lactation curve

• Derivatives of maximum daily yield and the
  persistency
• (Davydov, 1933)
• Graphical representation between milk production
  and lactation time starting at calving
• (Bodero et al.,1988)
• Importance of lactation curve
• Estimation purpose
• Farm management

5
Objectives of study

• To compare various lactation curve models in
  Vrindavani cattle under diseased and healthy
  conditions
• To study the effect of disease, Parity and
  calving season on lactation curve

6
Materials and Methods

• 1. Source and Collection of Data
• A total of 109047 daily milk yield records from
  360 Vrindavani cattle maintained at IVRI Farm,
  Bareilly, U.P, were taken for study
• Apart from milk production data (Daily milk yield
  from 1st to 305th day), Data regarding Animal
  number, Disease, Date of calving (Season of
  calving) and Parity of Animal ware recorded to
  study the effect of Parity, disease and calving
  season on Lactation Curves
• The estimated value of coefficient of
  heritability (standard error) from half-sib data
  for Vrindavani cattle milk production is 0.28578
  ( 0.29712)

7
Materials and Methods

• 2. Standard Lactation Curve Model
• Parabolic Exponential Model  (Sikka et al.,
  1950)
• Yt a exp(bt-ct2) exp(-ct)
• Gamma Function (Wood et al., 1967)
• Ytatb exp(-ct)
• Cobby and Le Du Yn (1978)
  
• Yta-bt-a exp(-ct)
• Exponential Model (Wilmink et al., 1987)
• Yt a b exp(-kt) ct
• Mixed Log Model (Guo et al., 1995)
• Yt abt-1/2cln(t)

8
Materials and Methods

• Mitscherlich x Exponential (Rook et al., 1993)
• Yt a(1-be-dt) exp(-ct)
• Ali Schaeffer Lactation Curve Model (1987)
• Yt a bd cd2 d?i e?i2
• Yt The production at time t a scale factor
  or milk yield at the beginning of lactation b
  The rate of change from initial production to
  maximum yield c The rate of change from
  maximum yield to the end of lactation k
  factor associated to the time of peak yield
  (0.065) d Parameter related to maximum milk
  yield e Parameter related to decline phase of
  lactation curve dt/305 and ?i loge(305/t)

9
Materials and Methods

• 3. Goodness of fit
• Goodness of fit was assessed by
• Coefficient of determination (R2)
• Adjusted coefficient of determination (R2adj)
• Akaikes Information Criteria (AIC)
• Bayesian information criterion (BIC)

10
Materials and Methods

• Effects of Disease and Parity
• Effects of disease and parity was studied by Two
  way Repeated Measures ANOVA
• yijµ gi ID(gi) Pj
  (g X P)ij eij
• µgenral mean effect
• gi effect of ith group
• Pjeffect of jth time period
• (gXP)ijinteraction effect of group and period
• eijerror term N(0, se2)

11
Results
12
Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Lactation order -1) along with measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Lactation order -1) along with measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Lactation order -1) along with measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Lactation order -1) along with measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Lactation order -1) along with measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Lactation order -1) along with measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Lactation order -1) along with measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Lactation order -1) along with measures of goodness of fit
Model Parameter Estimate SE AIC BIC
AS a 15.0689 0.8502 0.9700 0.9996 -702.38 -683.78
  b -10.1794 1.5076        
  c 2.4910 0.7160        
  d 0.3098 0.4386        
  e -0.4550 0.0566        
CL a 13.5932 0.0472 0.9610 0.9997 -633.29 -622.13
  b 0.0203 0.0003        
  c 0.1571 0.0035        
GS a 4.1167 0.1429 0.9680 0.9998 -696.52 -685.36
  b -1.2886 0.0147        
  c 4.4707 0.0625        
ME a 13.7150 0.0446 0.9700 0.9997 -712.38 -697.50
  b 0.7984 0.0176        
  c 0.1180 0.0039        
  d 0.0209 0.0002        
WL a 14.1374 0.0591 0.9450 0.9996 -528.35 -517.19
  b -8.4240 0.1918        
  c -0.0228 0.0003        
WD a 6.3027 0.1440 0.9280 0.9995 -444.34 -433.18
  b 0.2207 0.0067        
  c 0.0038 0.0001        
13
Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle
(Lactation Order -2) along with different measures of goodness of fit  (Lactation Order -2) along with different measures of goodness of fit  (Lactation Order -2) along with different measures of goodness of fit  (Lactation Order -2) along with different measures of goodness of fit  (Lactation Order -2) along with different measures of goodness of fit  (Lactation Order -2) along with different measures of goodness of fit  (Lactation Order -2) along with different measures of goodness of fit  (Lactation Order -2) along with different measures of goodness of fit 
Model Parameter Estimate SE AIC BIC
AS a 3.8256 0.9292 0.9820 0.9998 -648.20 -629.60
  b 12.7241 1.6476        
  c -11.1759 0.7825        
  d 6.5181 0.4794        
  e -1.2126 0.0619        
CL a 15.2699 0.0722 0.9520 0.9997 -360.36 -349.20
  b 0.0290 0.0004        
  c 0.1806 0.0060        
GS a 4.6967 0.2175 0.9630 0.9998 -440.59 -429.43
  b -1.6598 0.0224        
  c 5.3387 0.0951        
ME a 15.3931 0.0742 0.9550 0.9996 -380.95 -366.07
  b 0.8113 0.0296        
  c 0.1366 0.0072        
  d 0.0296 0.0004        
WL a 15.9356 0.0864 0.9410 0.9996 -296.26 -285.10
  b -8.9758 0.2806        
  c -0.0321 0.0005        
WD a 6.8333 0.1867 0.9380 0.9996 -282.53 -271.37
  b 0.2393 0.0081        
  c 0.0047 0.0001        
14
Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle
(Lactation Order -3) along with different measures of goodness of fit  (Lactation Order -3) along with different measures of goodness of fit  (Lactation Order -3) along with different measures of goodness of fit  (Lactation Order -3) along with different measures of goodness of fit  (Lactation Order -3) along with different measures of goodness of fit  (Lactation Order -3) along with different measures of goodness of fit  (Lactation Order -3) along with different measures of goodness of fit  (Lactation Order -3) along with different measures of goodness of fit 
Model Parameter Estimate SE AIC BIC
AS a 3.1860 1.3114 0.9740 0.9997 -438.06 -419.46
  b 16.0707 2.3252        
  c -14.6455 1.1043        
  d 7.3294 0.6765        
  e -1.3318 0.0873        
CL a 16.6527 0.1005 0.9360 0.9996 -166.76 -155.60
  b 0.0348 0.0005        
  c 0.1662 0.0067        
GS a 4.5500 0.3048 0.9490 0.9997 -234.59 -223.43
  b -1.9371 0.0314        
  c 6.1489 0.1333        
ME a 16.8625 0.1057 0.9420 0.9994 -191.39 -176.51
  b 0.7627 0.0329        
  c 0.1139 0.0073        
  d 0.0358 0.0006        
WL a 17.3698 0.1079 0.9350 0.9996 -160.85 -149.69
  b -10.2137 0.3504        
  c -0.0381 0.0006        
WD a 6.8618 0.2326 0.9270 0.9995 -125.09 -113.93
  b 0.2654 0.0101        
  c 0.0053 0.0001        
15
Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle Estimated value of Parameters of different lactation curves of Vrindavani Cattle
(Lactation order -4) along with different measures of goodness of fit  (Lactation order -4) along with different measures of goodness of fit  (Lactation order -4) along with different measures of goodness of fit  (Lactation order -4) along with different measures of goodness of fit  (Lactation order -4) along with different measures of goodness of fit  (Lactation order -4) along with different measures of goodness of fit  (Lactation order -4) along with different measures of goodness of fit  (Lactation order -4) along with different measures of goodness of fit 
Model Parameter Estimate SE AIC BIC
AS a 7.0254 1.2597 0.9760 0.9997 -462.58 -443.98
  b 9.5721 2.2336        
  c -10.5367 1.0608        
  d 6.3238 0.6498        
  e -1.2712 0.0839        
CL a 17.7444 0.0869 0.9520 0.9997 -252.48 -241.32
  b 0.0348 0.0005        
  c 0.1708 0.0057        
GS a 5.1120 0.2577 0.9640 0.9998 -337.11 -325.95
  b -1.9803 0.0265        
  c 6.3645 0.1127        
ME a 17.8978 0.0895 0.9560 0.9996 -274.74 -259.86
  b 0.8094 0.0292        
  c 0.1287 0.0068        
  d 0.0355 0.0005        
WL a 18.5096 0.1014 0.9430 0.9996 -199.12 -187.96
  b -10.7516 0.3291        
  c -0.0383 0.0005        
WD a 7.6523 0.2151 0.9400 0.9996 -184.92 -173.76
  b 0.2507 0.0084        
  c 0.0049 0.0001        
16
Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Healthy) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Healthy) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Healthy) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Healthy) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Healthy) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Healthy) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Healthy) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Healthy)
along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit 
Model Parameter Estimate SE AIC BIC
AS a 8.2073 0.8732 0.9820 0.9998 -686.15 -667.55
  b 4.4814 1.5482        
  c -6.6425 0.7353        
  d 4.3259 0.4504        
  e -0.9563 0.0582        
CL a 15.1213 0.0619 0.9610 0.9997 -460.73 -449.57
  b 0.0273 0.0003        
  c 0.1682 0.0047        
GS a 4.4899 0.1734 0.9730 0.9998 -578.56 -567.40
  b -1.6012 0.0178        
  c 5.2566 0.0758        
ME a 15.2652 0.0619 0.9660 0.9997 -505.20 -490.32
  b 0.7936 0.0229        
  c 0.1237 0.0052        
  d 0.0280 0.0003        
WL a 15.7608 0.0735 0.9510 0.9997 -395.08 -383.92
  b -9.1592 0.2387        
  c -0.0303 0.0004        
WD a 6.7101 0.1587 0.9480 0.9997 -376.63 -365.46
  b 0.2393 0.0070        
  c 0.0045 0.0001        
17
Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Other Disease) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Other Disease) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Other Disease) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Other Disease) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Other Disease) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Other Disease) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Other Disease) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Other Disease)
along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit 
Model Parameter Estimate SE AIC BIC
AS a 15.3713 0.9731 0.9830 0.9998 -620.05 -601.45
  b -21.6170 1.7254        
  c 9.4921 0.8195        
  d -0.0742 0.5020        
  e -0.3645 0.0648        
CL a 11.8756 0.0635 0.9660 0.9998 -415.10 -403.94
  b 0.0314 0.0004        
  c 0.2473 0.0110        
GS a 6.0467 0.2213 0.9670 0.9998 -429.92 -418.76
  b -1.4179 0.0228        
  c 3.6851 0.0968        
ME a 11.9154 0.0647 0.9670 0.9997 -424.36 -409.48
  b 0.8237 0.0462        
  c 0.2001 0.0152        
  d 0.0316 0.0004        
WL a 12.2543 0.0915 0.9430 0.9996 -261.33 -250.17
  b -5.0128 0.2972        
  c -0.0331 0.0005        
WD a 6.1629 0.1444 0.9740 0.9998 -504.10 -492.94
  b 0.2302 0.0074        
  c 0.0069 0.0001        
18
Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Lamness) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Lamness) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Lamness) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Lamness) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Lamness) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Lamness) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Lamness) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Lamness)
along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit 
Model Parameter Estimate SE AIC BIC
AS a 14.1090 1.0532 0.9780 0.9997 -571.77 -553.17
  b -13.5483 1.8675        
  c 3.0931 0.8869        
  d 0.5073 0.5433        
  e -0.4240 0.0701        
CL a 12.9268 0.0536 0.9750 0.9998 -531.56 -520.40
  b 0.0308 0.0003        
  c 0.2056 0.0064        
GS a 5.0991 0.1728 0.9790 0.9999 -580.69 -569.53
  b -1.5318 0.0178        
  c 4.3993 0.0756        
ME a 13.0184 0.0529 0.9780 0.9998 -575.60 -560.72
  b 0.7715 0.0270        
  c 0.1501 0.0075        
  d 0.0312 0.0003        
WL a 13.4440 0.0698 0.9640 0.9998 -426.79 -415.62
  b -6.7113 0.2266        
  c -0.0332 0.0004        
WD a 6.0251 0.1387 0.9710 0.9998 -488.04 -476.88
  b 0.2452 0.0071        
  c 0.0061 0.0001        
19
Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Mastitis) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Mastitis) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Mastitis) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Mastitis) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Mastitis) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Mastitis) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Mastitis) Estimated value of Parameters of different lactation curves of Vrindavani Cattle (Mastitis)
along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit  along with different measures of goodness of fit 
Model Parameter Estimate SE AIC BIC
AS a 14.4725 0.5441 0.9930 0.9999 -974.70 -956.10
  b -14.6273 0.9647        
  c 3.6832 0.4582        
  d -0.1539 0.2807        
  e -0.3532 0.0362        
CL a 12.1212 0.0342 0.9880 0.9999 -823.46 -812.30
  b 0.0285 0.0002        
  c 0.1665 0.0032        
GS a 3.7617 0.0882 0.9930 1.0000 -990.76 -979.60
  b -1.4808 0.0091        
  c 4.4506 0.0386        
ME a 12.2278 0.0299 0.9920 0.9999 -948.06 -933.18
  b 0.7924 0.0138        
  c 0.1238 0.0032        
  d 0.0290 0.0002        
WL a 12.6114 0.0477 0.9800 0.9999 -659.12 -647.96
  b -7.2503 0.1548        
  c -0.0308 0.0003        
WD a 5.0357 0.0880 0.9840 0.9999 -726.62 -715.46
  b 0.2748 0.0053        
  c 0.0062 0.0001        
20
Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in rainy season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in rainy season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in rainy season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in rainy season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in rainy season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in rainy season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in rainy season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in rainy season) along with different measures of goodness of fit
Model Parameter Estimate SE AIC BIC
AS a -2.6322 0.7326 0.9790 0.9997 -793.20 -774.60
  b 29.4966 1.2990        
  c -20.9391 0.6169        
  d 7.9217 0.3779        
  e -1.2654 0.0488        
CL a 13.5904 0.1210 0.7570 0.9984 -57.50 -46.34
  b 0.0182 0.0007        
  c 0.1593 0.0093        
GS a 3.0562 0.3299 0.8410 0.9990 -186.28 -175.12
  b -1.3020 0.0340        
  c 4.7968 0.1443        
ME a 32.0865 6.4049 0.8590 0.9986 -220.14 -205.25
  b 0.7065 0.0553        
  c 0.0059 0.0013        
  d 0.0723 0.0130        
WL a 14.2288 0.1182 0.7920 0.9986 -105.50 -94.34
  b -8.8268 0.3837        
  c -0.0211 0.0006        
WD a 5.2884 0.1900 0.8510 0.9990 -207.07 -195.91
  b 0.2671 0.0104        
  c 0.0038 0.0001        
21
Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in winter season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in winter season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in winter season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in winter season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in winter season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in winter season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in winter season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in winter season) along with different measures of goodness of fit
Model Parameter Estimate SE AIC BIC
AS a 16.4170 1.1134 0.9830 0.9998 -537.87 -519.27
  b -10.4830 1.9742        
  c -0.4641 0.9376        
  d 1.4650 0.5744        
  e -0.6976 0.0742        
CL a 17.1301 0.0647 0.9760 0.9998 -447.11 -435.95
  b 0.0371 0.0004        
  c 0.1478 0.0035        
GS a 4.3642 0.1823 0.9830 0.9999 -548.20 -537.04
  b -2.0354 0.0188        
  c 6.4469 0.0797        
ME a 17.2994 0.0626 0.9810 0.9998 -515.55 -500.67
  b 0.8008 0.0185        
  c 0.1107 0.0038        
  d 0.0378 0.0003        
WL a 17.8145 0.0747 0.9710 0.9998 -384.84 -373.68
  b -11.0615 0.2427        
  c -0.0402 0.0004        
WD a 6.7799 0.1591 0.9670 0.9998 -344.79 -333.63
  b 0.2793 0.0070        
  c 0.0057 0.0001        
22
Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in summer season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in summer season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in summer season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in summer season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in summer season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in summer season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in summer season) along with different measures of goodness of fit Estimated value of Parameters of different lactation curves of Vrindavani Cattle (calving in summer season) along with different measures of goodness of fit
Model Parameter Estimate SE AIC BIC
AS a 3.4021 0.9648 0.9550 0.9994 -625.26 -606.66
  b 8.2296 1.7107        
  c -4.4075 0.8125        
  d 6.1732 0.4977        
  e -1.1385 0.0643        
CL a 12.9750 0.0452 0.9550 0.9997 -626.13 -614.97
  b 0.0185 0.0002        
  c 0.2351 0.0067        
GS a 6.0883 0.2087 0.9230 0.9995 -465.64 -454.48
  b -1.0857 0.0215        
  c 3.5000 0.0913        
ME a 12.9993 0.0458 0.9560 0.9996 -630.83 -615.95
  b 0.9055 0.0314        
  c 0.2106 0.0098        
  d 0.0186 0.0003        
WL a 13.4346 0.0825 0.8780 0.9992 -324.73 -313.57
  b -5.9686 0.2678        
  c -0.0207 0.0004        
WD a 7.7212 0.2089 0.8680 0.9991 -298.97 -287.81
  b 0.1526 0.0081        
  c 0.0031 0.0001        
23

4th parity cattle is superior in milk production
and produce 15.6, 12.4 and 8.2 more milk w.r.t
LO1,2 3 resp.
24
Cow calving in winter season produced 11.3, 6.7
more milk than cow calving in summer and rainy
season
25
Production loss
Healthy cattle produces 30, 24 and 35 more
milk w.r.t cow suffered from Mastitis, Lameness
and other disease respectively
26
Conclusions

• The estimated value of coefficient of
  heritability (S.E) of milk production is 0.28578
  (0.29712)
• Ali Schaeffer lactation curve model was best
  fitted to DTDMY records of Vrindavani Cattle in
  LO-2, LO-3, LO-4, cow calving in rainy season,
  and cow suffered from other disease
• Mitscherlich cum Exponential was best fitted to
  DTDMY records of Vrindavani Cattle in LO-1 and
  cow calving in Summer season whereas Mixed log
  model was best fitted to DTDMY records of
  Vrindavani Cattle in diseased condition
  (Lameness, Mastitis) and cow calving in winter
  season

27
Conclusions

• Mixed log model and Cobby Le Du model under
  predict the initial stage milk production
  whereas, all Model under- predict the peak
  production
• Vrindavani cattle calving in winter season
  produced 11.3, 6.7 more milk than cow calving
  in summer and rainy season respectively
• Loss in milk production of diseased Vrindavani
  cattle with respect to healthy cattle suffered
  from Mastitis, Lameness and other disease was
  30, 24 and 35 respectively

28
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