covariates measured with various imprecision

[SBuc]

Dear Listers, 

I want to analyse the following dataset. 

We have farms where we measured the success of a procedure (x success of n event). 

for every farm we have covariates (X1, ..., X9) which are defined as proportion of calves with a specific event  in a specific farm (ex proportion of calves drinking the first meal less than 6 hours after birth..., so a proportion y events of m calves assessed).

Now I have for different farms different m. I want to incorporate in my analysis the uncertainty around my covariates' proportion eg how accounting the fact that X1 can be 50% with some farms with 10 events of 20 trial vs 4 of 8 ...

I don't know if it is possible accounting for this specificity.