Methaemoglobinaemia is a rare but potentially dangerous haemoglobinopathy that is often underdiagnosed. It is one of the causes for unexplained cyanosis with dark-coloured blood. especially in the absence of cardiac or pulmonary pathology. Not uncommonly so. https://www.bekindtopets.com/hot-mega-Sweetlix-16-8-Meat-Maker-with-Rumensin-18-lb-limited-choice/