Meet a group of nursery pigs on a Wisconsin farm. Eight weeks old, thriving, gaining weight faster than any other group this season. The farmer is proud of them. Then one morning he finds three dead with no warning. The next day, two more. The pigs that died were the biggest, fastest-growing animals in the barn. You perform a necropsy. When you open the chest and look at the heart, you stop. The cardiac muscle is streaked with pale white bands of necrosis alternating with dark hemorrhagic zones, creating a mottled purple and cream pattern. It looks exactly like a mulberry. This is mulberry heart disease, caused by combined selenium and vitamin E deficiency. Selenium normally sits inside the glutathione peroxidase enzyme, neutralizing the peroxides that would otherwise destroy cell membranes. Vitamin E waits inside the membranes themselves, stopping lipid peroxidation chain reactions in progress. Remove both and cardiac muscle, running continuously at high metabolic demand, is defenseless. The fastest-growing pigs died first because they needed the most antioxidant protection and had the least. Feed analysis confirms selenium at 0.12 mg/kg. It should be 0.3. 💡 The takeaway: In selenium-deficient regions, the pigs you lose first are often your best ones. For more information on this condition, see the classroom or follow the link below: https://www.skool.com/pre-vet-skool-9535/classroom/d804917a?md=a3f90a53671b4c3999e646decb930a26