Liver flukes can be deadly and can wipe out an entire herd. They are common in papyrus and young spear grass so goats that graze near streams with papyrus and tall spear grass can be affected. However, timely deworming can keep the effects at bay.
You need to deworm at least every after three months. You should also clear any nearby stagnant waters because they can also breed the flukes.
You can deworm using injectable drugs like vermectin while orals include albendazoles, levamizoles and combinations of levamizoles with oxyclozanide.