This blood feeding nematode elicits haemorrhagic gastritis, anemia, oedema, and associated symptoms by nurturing on capillaries of gastric mucosa [97, 98]. H. contortus has a large set of secreted peptidases and peptidase inhibitors that function in host penetration, blood feeding, and blood-digestion [97–100]. This evidence concerns the gene LAP3 and anemia (phenotype).