Anatomy lesson

The statement/answer in the Hands On Pop Quiz for your Autumn 2021 edition (“Comparative Anatomy,” EQUUS 506) is partially right and partially wrong.

The horse does not have a gall bladder, as is stated. However, the appendix and cecum are 2 different structures. Both humans and horses have a cecum, albeit it is quite small in humans and quite large in horses.

Humans (and some other species) additionally have an appendix that is attached to the “blind” end of the cecum. Horses (and other common domestic mammals) do not have an appendix, nor does the appendix become the cecum (a fairly common misconception).

Therefore, both a and b answers in your pop quiz are correct.

Lola C. Hudson, DVM PhD

Apex, North Carolina