The core logic behind the occurrence of diarrhea in beef cattle due to high concentrate feed is as follows: High starch disrupts the rumen microecological balance → Undigested substances enter the intestine → Abnormal posterior intestinal fermentation and increased osmotic pressure → Disruption of intestinal function → Diarrhea. This process involves the interaction of multiple links, ultimately leading to symptoms such as soft feces or diarrhea in beef cattle.