milkman {doBy}

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 “Malkekoens energibalance og mobilisering” project; both were funded by the Danish Ministry of Food, Agriculture and Fisheries and the Danish Cattle Association.

Examples

data(milkman)