I would imagine it could be other species of blood suckers that live at home. Bed bugs could be a culprit, they leave what looks like flea dirt on the prey and are so small you can not see them, you litterally need a dog to come in and sniff them out as only the adults are visible to the average naked eye.
Bed bugs dont stay on their prey either, they eat their fill and then recede back in their hiding place.
Kissing bugs are another possible culprit.. but they are pretty big so I think you would know if you had them.
You could probably have fleas in your home but if she didnt find any fleas or nits maybe its something else or maybe its not flea dirt at all just some other particulate that appears to be flea dirt?
You should wash your dogs bed, flip your matris, wash all your sheets and linins. Just to be safe you don't have something living in your house feeding on your dog
Bed bugs dont stay on their prey either, they eat their fill and then recede back in their hiding place.
Kissing bugs are another possible culprit.. but they are pretty big so I think you would know if you had them.
You could probably have fleas in your home but if she didnt find any fleas or nits maybe its something else or maybe its not flea dirt at all just some other particulate that appears to be flea dirt?
You should wash your dogs bed, flip your matris, wash all your sheets and linins. Just to be safe you don't have something living in your house feeding on your dog