R: Milk yield data for manually milked cows.

milkman {doBy} | R Documentation

## Milk yield data for manually milked cows.

### Description

Milk yield data for cows milked manually twice a day (morning and evening).

### Usage

    milkman

### Format

A data frame with 161836 observations on the following 12 variables.

`cowno`

  a numeric vector; cow identification

`lactno`

  a numeric vector; lactation number

`ampm`

  a numeric vector; milking time: 1: morning; 2: evening

`dfc`

  a numeric vector; days from calving

`my`

  a numeric vector; milk yield (kg)

`fatpct`

  a numeric vector; fat percentage

`protpct`

  a numeric vector; protein percentage

`lactpct`

  a numeric vector; lactose percentage

`scc`

  a numeric vector; somatic cell counts

`race`

  a factor with levels `RDM` `Holstein` `Jersey`

`ecmy`

  a numeric vector; energy corrected milk

`cowlact`

  Combination of cowno and lactno; necessary because the same cow may appear more than once in the dataset (in different lactations)

### Details

There are data for 222 cows. Some cows appear more than once in the dataset (in different lactations) and there are 288 different lactations.

### References

Friggens, N. C.; Ridder, C. and Løvendahl, P. (2007). On the Use of Milk Composition Measures to Predict the Energy Balance of Dairy Cows. J. Dairy Sci. 90:5453–5467 doi:10.3168/jds.2006-821.

This study was part of the Biosens project used data from the “Mælkekoens energibalance og mobilisering” project; both were funded by the Danish Ministry of Food, Agriculture and Fisheries and the Danish Cattle Association.

### Examples

    data(milkman)

[Package doBy version 4.6.5 Index]