lactation.calf.model: The Lactation model
In ZeBook: Working with Dynamic Models for Agriculture and Environment

Description Usage Arguments Value Examples

Model description. This model is a model of lactating mammary glands of cattle described by Heather et al. (1983). This model was then inspired more complex models based on these principles. This model simulates the dynamics of the production of cow's milk. the system is represented by 6 state variables: change in hormone levels (H), the production and loss of milk secreting cells (CS), and removing the secretion of milk (M), the average quantity of milk contained in the animal (Mmean), the amount of milk removed (RM) and yield (Y). The model has a time step dt = 0.1 for regular consumption of milk by a calf. The model is defined by a few equations, with a total of fourteen parameters for the described process.

1 2	lactation.calf.model(cu, kdiv, kdl, kdh, km, ksl, kr, ks, ksm, mh, mm, p, mum, rc, duration, dt)

`cu`	: number of undifferentiated cells
`kdiv`	: cell division rate, Michaelis-Menten constant
`kdl`	: constant degradation of milk
`kdh`	: rate of decomposition of the hormone
`km`	: constant secretion of milk
`ksl`	: milk secretion rate, Michaelis-Menten constant
`kr`	: average milk constant
`ks`	: rate of degradation of the basal cells
`ksm`	: constant rate of degradation of milk secreting cells
`mh`	: parameter
`mm`	: storage Capacity milk the animal
`p`	: parameter
`mum`	: setting the maximum rate of cell division
`rc`	: parameter of milk m (t) function
`duration`	: duration of simulation
`dt`	: time step

data.frame with CS, M, Mmoy, RM, day, week

1	lactation.calf.model2(lactation.define.param()["nominal",],300,0.1)

      week         M       Mmoy       CS       RM
 [1,]    0  1.959912  0.1979127 2660.532 11.41181
 [2,]    1  6.481227  1.3410402 5458.517 23.45890
 [3,]    2 11.327486  3.5510203 6806.066 28.68241
 [4,]    3 14.633670  6.3156298 7417.833 30.69344
 [5,]    4 16.130573  8.9517245 7663.076 31.38036
 [6,]    5 16.560699 11.0859653 7724.089 31.55814
 [7,]    6 16.457568 12.6450191 7690.090 31.51636
 [8,]    7 16.069055 13.6824083 7604.779 31.35529
 [9,]    8 15.515307 14.2853523 7491.044 31.11501
[10,]    9 14.867873 14.5422046 7362.316 30.81670
[11,]   10 14.174290 14.5327040 7226.456 30.47417
[12,]   11 13.463257 14.3245057 7087.167 30.09551
[13,]   12 12.748816 13.9718050 6945.352 29.68349
[14,]   13 12.036879 13.5159428 6800.569 29.23734
[15,]   14 11.331038 12.9876756 6652.105 28.75523
[16,]   15 10.635550 12.4100553 6499.509 28.23602
[17,]   16  9.955806 11.8009379 6342.711 27.68008
[18,]   17  9.297560 11.1746928 6181.953 27.08928
[19,]   18  8.665965 10.5431565 6017.671 26.46661
[20,]   19  8.064959  9.9160827 5850.385 25.81569
[21,]   20  7.497047  9.3013494 5680.637 25.14037
[22,]   21  6.963408  8.7050959 5508.960 24.44449
[23,]   22  6.464142  8.1318754 5335.862 23.73172
[24,]   23  5.998552  7.5848425 5161.833 23.00556
[25,]   24  5.565405  7.0659649 4987.341 22.26928
[26,]   25  5.163134  6.5762413 4812.840 21.52595
[27,]   26  4.789989  6.1159063 4638.772 20.77846
[28,]   27  4.444147  5.6846142 4465.568 20.02954
[29,]   28  4.123776  5.2815939 4293.645 19.28176
[30,]   29  3.827093  4.9057776 4123.404 18.53753
[31,]   30  3.552384  4.5559025 3955.229 17.79909
[32,]   31  3.298024  4.2305899 3789.487 17.06855
[33,]   32  3.062487  3.9284054 3626.518 16.34784
[34,]   33  2.844349  3.6479033 3466.640 15.63874
[35,]   34  2.642285  3.3876590 3310.145 14.94287
[36,]   35  2.455066  3.1462907 3157.294 14.26167
[37,]   36  2.281559  2.9224751 3008.320 13.59643
[38,]   37  2.120716  2.7149555 2863.426 12.94826
[39,]   38  1.971572  2.5225479 2722.787 12.31814
[40,]   39  1.833237  2.3441420 2586.543 11.70685
[41,]   40  1.704893  2.1787014 2454.810 11.11507
[42,]   41  1.585787  2.0252619 2327.671 10.54328
[43,]   42  1.482007  1.8916573 2212.872 10.02648