Descending part

The descending part of duodenum (Pars descendens duodeni) begins at the cranial duodenal flexure and runs caudally, more or less far depending on the species, along the right border of the lumbar region or in the right flank.

It is short in Humans, Equids, and Pigs, where it barely surpasses the level of the right kidney’s symphysis, but is much longer in Carnivores and even more so in Ruminants and Rabbits, where it reaches near the iliac region. It usually ends at the caudal duodenal flexure (Flexura duodeni caudalis).