Putangitangi and KNERSIE, I don't think he has parasites. I treat my cattle at least twice per year and on occasion if ones in the chute, they may get 3 treatments per year. I use on an alternating basis, pour on and injectable. I also alternate between brands. I will check his Individual Treatment Sheet tomorrow to make sure he has not been missed.
I have more experience than the average person with parasites. I have had several Invertebrate Zoology classes including Medical and General Parasitology. Liver flukes in cattle are Fasciola hepatica.
Just of interest to some, KNERSIE is in a part of the world just north of him where another genus of trematode, Schistosoma, commonly known as blood-flukes cause a condition in humans called bilharzia. The medical term is schistosomasis, and is considered by the World Health Organization as the second most socioeconomically devastating parasitic disease, next only to malaria.
UPDATE Not likely to be liver flukes. Based on a very quick check of google data on Fasciola hepatica in cattle. Kentucky did not come up. Found that the Gulf Coast States, NW States, and Northern States are where it occurs in the US. The snail that is the intermediate host for the intermediary phases of Fasciola hepatica require a wet climate. My land is well drained (in fact you might say it is steep). Maybe Lucky_P can say if he has seen any clinical cases in KY.