Heat Cycle Regularity - Page 1

I have a female whom I expected to be in heat in March, I have not seen the cycle come on yet.
She according to her breeder/previous owner had a heat in March or 09, and while I had her cycled in September 09.
I had her housed with the potential sire of the pups during the month of March but never saw any sign of heat and have yet to see any sign of pregnancy.
I am wondering if she perhaps did not cycle or maybe cycled later than expected and I missed it?

You really need to monitor you bitch. You need to know exactly when she she starts her heat and only put her with the stud when she is ready to accept him.
Just by the way have you done hips, elbows and all of the other health checks first before breeding these 2 dogs?

I doubt very much if you missed it, she maybe skipped a cycle.

Is anyone else seeing heat cycle irregularites?  I have two females, one of which had what I thought was a split cycle but never came back in and another who has gone 8.5 months since her last cycle. I have several friends who are also experiencing similar issues.  There seems to be no commonality.  Different areas of the county, no diet changes, no similar diet (some raw fed, some kibble) and all the dogs seem healthy and when they do conceive produce healthy and robust litters. 
Judy

 I don't think you would have missed it either, I am sue you would have noticed the male being interested even a few days before, unless you really were not observing them at all.  I also do not think it is that unusual for the length of the cycle to vary somewhat, I have one female who usually is every 6 months, but once went 8 months between cycles.