How to make a poisson model with categorical data

#1
Hi,
i am having trouble making a model for this data
we have a categorical treatment with 4 levels with 3 other blocking terms.

scrat.glm<-glm(scrat$Scratching~treatment + Day + Pig + Shed + Pen, family= quasipoisson, data= scrat)

this is the model i was trying to make but it doesnt seem to be right.
i dont know what to do im new to stats :(