Final answer:
Ostertagiosis is the most common protein-losing enteropathy in cattle, characterized by damage to the gastric glands and inflammation of the abomasal lining leading to protein loss, diarrhea, weight loss, and anemia.
Step-by-step explanation:
The most common protein-losing enteropathy in cattle is ostertagiosis, which is caused by the parasite Ostertagia. This condition can lead to significant protein loss through the gut due to damage to the gastric glands and inflammation of the abomasal lining. Cattle affected by ostertagiosis may present with diarrhea, weight loss, and anemia.