Cows that have held cleanings, had twins or hard calvings should get a washout around two weeks after calving. You must keep accurate records to know what needs a washout. Most farmers have moved away from using iodine-based washouts and instead use an antibiotic-based product.
A retained cleaning usually signifies another problem, either a mineral deficiency or a product of a hard calving. Either way, monitor the cows closely and get veterinary help if the cow is sick with a high temperature.
Retained cleanings: The dos and don'ts