Toxicity lesions in broilers: This image shows a blackish proventriculus and friable liver in broilers. There are 3 main causes for this: histamine toxicity derived from the amino acid histidine in some protein concentrate (fish meal, meat meal or blood derived products); toxicity due to Clostridium toxins existing in some raw material; and aflatoxin toxicity in cereals. It is recommended to supplement the mycotoxin binder (Alquerfeed Antitox) in trays ad libitum for the birds to self-dose; also supplement new feed low in energy and protein for 3 days; finally, supplement B vitamins through drinking water.