Updates?
Sorry for the radio silence, I missed Nelli's' window by a day or two, she never hooked up with the stud; tail wagging and flirted a lot, just never hooked up. She probably doesn't know what 'hooking up' looks like living with me nowadays lol 
The millisecond she shows sign, off she goes for another attempt. Probably next month or June.
I opted for Embark genetic testing... kinda pricey but it was easy enough. Swab the mouth, wait, results are published to the web. For those interested Nelli's results: http://embk.me/superbenelli
That's a bummer, we are hoping that we will see the drippy blood trail signs for Rey some time in the next month for another go at breeding. We tried last Fall, the male's owner only does AI, so have a year to try again at no additional cost... well, besides hormone testing, vet visits, etc.
Good luck.