Amprolium is a coccidiostat

Coccidiostat

A coccidiostat is an antiprotozoal agent that acts upon Coccidia parasites.Examples include:* amprolium* arprinocid* artemether* clopidol* decoquinate* diclazuril* dinitolmide* ethopabate* halofuginone* lasalocid* monensin* narasin* nicarbazin...

 used in poultry

Poultry

Poultry are domesticated birds kept by humans for the purpose of producing eggs, meat, and/or feathers. These most typically are members of the superorder Galloanserae , especially the order Galliformes and the family Anatidae , commonly known as "waterfowl"...

.

Synthesis

The drug is a thiamine

Thiamine

Thiamine or thiamin or vitamin B1 , named as the "thio-vitamine" is a water-soluble vitamin of the B complex. First named aneurin for the detrimental neurological effects if not present in the diet, it was eventually assigned the generic descriptor name vitamin B1. Its phosphate derivatives are...

 analogue and blocks the thiamine transporter of Eimeria

Eimeria

Eimeria is a genus of Apicomplexan parasites that includes various species responsible for the poultry disease coccidiosis. The genus is named for the German zoologist Theodor Eimer...

species. By blocking thiamine uptake it prevents carbohydrate synthesis.

Despite only moderate efficacy it is well favoured due to few resistance issues and is commonly used in conjunction with sulphonamides prophylactically in chicken

Chicken

The chicken is a domesticated fowl, a subspecies of the Red Junglefowl. As one of the most common and widespread domestic animals, and with a population of more than 24 billion in 2003, there are more chickens in the world than any other species of bird...

s and cattle

Cattle

Cattle are the most common type of large domesticated ungulates. They are a prominent modern member of the subfamily Bovinae, are the most widespread species of the genus Bos, and are most commonly classified collectively as Bos primigenius...

as a coccidiostat.