Heat - how long in between

Question
How long inbetween heats for a dog

Answer
Generally it is 5-1/2 to 6 months, but some do go a bit longer, just as some can go a bit shorter. If they come in sooner, or later (particularly if the change in cycle time is abnormal), it can be a sign of thyroid deficiency. Some breeds, such as basenjis, tend to come in only once a year.