agridat (version 1.23)

zuidhof.broiler: Daily weight, feed, egg measurements for a broiler chicken

Description

Daily weight, feed, egg measurements for a broiler chicken

Format

A data frame with 59 observations on the following 6 variables.

bw

Body weight, grams

targetbw

Target body weight, grams

adfi

Average daily feed intake, grams

adg

Average daily gain, grams

eggwt

Egg weight, grams

age

Age, days

Details

Using graphs like the one in the examples section, the authors discovered that a drop in body weight commonly occurs around the time of first egg production.

Used with permission of Martin Zuidhof.

Examples

if (FALSE) {
library(agridat)
data(zuidhof.broiler)
dat <- zuidhof.broiler

dat <- transform(dat, age=age/7) # Change days into weeks

# Reproducing figure 1 of Zuidhof et al.

# Plot using left axis
op <- par(mar=c(5,4,4,4))
plot(bw~age, dat, xlab="Age (weeks)", ylab="Bodyweight (g)",
     main="zuidhof.broiler",
     xlim=c(20,32), ylim=c(0,4000), pch=20)
lines(targetbw~age, subset(dat, !is.na(targetbw)), col="black")

# Now plot using the right axis
par(new=TRUE)
plot(adfi~age, subset(dat, !is.na(adfi)),
     xlab="", ylab="", xlim=c(20,32), xaxt="n",yaxt="n",
     ylim=c(-50,175), type="s", lty=2)
axis(4, at=c(-50,-25,0,25,50,75,100,125,150,175), col="red", col.axis="red")
mtext("Weight (g)", side=4, line=2, col="red")
lines(adg~age, subset(dat, !is.na(adg)), col="red", type="s", lty=1, lwd=2)
abline(h=c(0,52), col="red")
with(dat, segments(age, 0, age, eggwt, col="red"))

legend(20, -40, c("Body weight", "Target BW", "Feed/day", "Gain/day", "Egg wt"),
       bty="n", cex=.5, ncol=5,
       col=c("black","black","red","red","red"),
       lty=c(-1,1,2,1,1), lwd=c(1,1,1,2,1), pch=c(20,-1,-1,-1,-1))
par(op)
}