Are these cracks (spaces with no follicles) normal 4 - 5 days after a hair transplant? (Photos)

It would be best to contact your doctor for a follow up exam.  You are likely not washing your hair / scalp well enough.

The areas where no grafts (follicles) are visible will not grow any hairs but hopefully the adjacent grafts will provide adequate coverage.Your physician probably felt this spacing would ensure that the grafts had enough blood supply to support healthy growth.However,like many patients you may decide to do another procedure in the future to further increase density in that area.

Cracks
in recipient area after hair transplant are secondary to aggregation of your
scalp.  This is not uncommon and won’t
affect the final result of your hair transplant as long as they are washed
properly before the procedure. At this point, I would wait to see how you look
at one year then reevaluate your options. 
Lastly, you should follow up with your hair restoration physician.

It is likely that these "cracks" are empty areas that were not transplanted, and will not grow hair. Usually the transplanted hairs start to fall out around day 7 or so, and the only way to really tell is waiting for your final result in 12 months. 

Those areas not cracks , just empty areas. Number of transplanted hair is low on both side and of course these empty areas will yield no hair in future . You will need a second op to increase density .

It is very difficult to tell at 5 days what you actually looked like immediately after the surgery. Ask your doctor for your post operative pictures