VetResearchLMM has R codes and data sets for Linear Mixed Models: An Introduction with applications in Veterinary Research by Duchateau, L. and Janssen, P. and Rowlands, G. J.
Stable version of the package avialabe on CRAN can be installed using:
install.packages('VetResearchLMM')
Development version of the package avialabe on Github can be installed using:
if(!require("devtools")) install.packages("devtools")
devtools::install_github('myaseen208/VetResearchLMM', build_vignettes = TRUE)