dog in heat

[dakids]

My yellow lab Lucy has just come into heat in the last day or 2.  She is humping everything.  Our fixed beagle is getting the brunt of it and he is very confused.  How long will it last?  I want to get her hips certified and we have to wait until she is 2 before getting certified and then we will breed her. 

[NDGUY]

typically a 21 day cycle.... a 7 day climb then 7 days prime and 7 days to come down