Yes, there are fertile creatures with an odd number of chromosomes!

A whole lot of them, actually. But it's not related to hybrids.

Namely some insects, due to something known as haplodiploidity, where males of some species will be haploid, having only one set of chromosomes, instead of e.g. two like the females of their species, or all humans.

Meaning that in those species that have an uneven number of chomosome pairs, the males will have an uneven number of chromosomes overall.

One good example woule be the Jack Jumper Ant, where males are haploid, possessing just a single Chromosome!