The modern philosophy of parasite control is based on prevention. Prevention of environmental contamination with parasite eggs is the goal. As all the parasites discussed are spread through feces, pasture and paddock manure management is very important in the control of these parasites.
Certain practices can help you achieve that goal. Keeping the horse population density in a pasture low is an important factor in reducing the amount of eggs shed on the pasture. If size of the pasture and the number of horses on it make this practical, routinely picking up the feces is a very efficient way to eliminate pasture contamination. The feces collected should be composted and not spread back on grazing pastures.
As parasite larvae are very sensitive to desiccation (the drying effect of direct sun and wind), mowing or harrowing a pasture will help to destroy them. The horses must be removed from the pasture for several days after this is done to allow time for these larvae to be destroyed.