From the article below:
Months before their disappearance,
an Amish farmer in the area witnessed dozens of cattle in Nelson’s care die over the winter.
...
“Two bales of straw and two bales of silage for 312 head wasn't even close to enough,” Gingrich recalled.
...
The farmer said that Nelson eventually hauled off the animals that could stand on their own, leaving around 170 dead cattle on Gingrich’s property. He said Nelson also left several cattle that were too sick to walk.
Landowner says murder suspect starved more than 150 cattle to death
What a monster. There's no way (IMO) that the Nelson family knew nothing about it. Was it just the cost of doing business to them?
How likely is it that the cattle belonged to the Diemels?