Unwanted Dog Covering
At the peak of the heat period, that is its final phase, a minute of distraction is enough for an unwanted coupling.
As covering forhave its own rules, probabilities to find them while coupling are big.
It all depends on how we behave: never try to separate them, forget water cubes or hitting them! It would be a useless mistreatment, because insemination already took place. Do not approach excessively to the couple, you could get bite. Make a date with your vet. The female dog can receive a first injection three days after covering and two more afterwards.
Important: Injections prolong heats. You must then keep watching for a longer time to solve any error in the "vigilance system".