A total of 499 cats were sampled and tested for FIV in the 15 populations. There was large variability in the number of cats sampled due to large differences in population sizes, ranging from 13 cats in Clerey-la-Côte to 71 in Sauvigny. The overall sex-ratio is close to 50% but with differences between populations, although it does not differ statistically from a 50:50 binomial distribution (x 2 = 17.21, 15 df, p = 0.31). However, in Ruppes the sex-ratio is rather high (0.79) and this value significantly differs from 0.5 when applying a Bonferroni correction for multiple tests (p,0.05).