A Little Bit About Goats And Some Cool Anatomy Terms

I really like goats. SelfSufficientNurse is responsible for getting me excited about goats as she breeds and raises them.

I've learned about some unique aspects of goat anatomy in the past few weeks.

1. Goats lack a facial artery. (So do sheep). Practically, you can't take a pulse over the mandible for this reason. The lingual artery comes directly off the carotid artery. Arterial blood supply to the lateral face is provided by the transverse facial artery.

2. You have to anesthetize two branches of the cornual nerve, not just one as in the cow, to dehorn a goat. The two branches are a cornual branch of trigeminal nerve origin (zygomaticotemporal branch off the zygomatic nerve, said to be lacrimal too) located ventrally and cornual branches of the infratrochlear nerve located dorsally (exits from a depression in the dorsal bony orbit).

3. Goats (and sheep) may have a complete right azygous vein in addition to a left azygous vein (both draining the dorsal intercostal spaces in the thorax).

So there. Life really isn't that exciting when you are immersed in anatomy.

My favorite term so far--planum nasolabial, which is a tough plate of tissue separating the nostrils of cows.

Some other interesting terms--

• Plica vena cava-- a fold of pleura that extends from the mediastinum containing the caudal vena cava and right phrenic nerve; it is separated from the mediastinum by the right accessory lung lobe on which it leaves an indentation
  

• Trabecula septomarginalis (aka moderator band)-- Purkinje fibers that connect the interventricular septum and and the free wall of the right ventricle in order to coordinate the concurrent contraction of the cardiac muscle from apex to base
  

• Cupula pleurae-- parietal pleura that extends cranial to the thoracic inlet (in the cow more extensive on the right). I found this a very confusing concept in tech school-- that part of the lungs extend beyond the boundary of the "bony thorax"-- I've heard the extension being farther on one side as the reason one side is more prone to pneumothorax due to trauma, particularly in small animals and humans

• Supreme intercostal artery-- Artery that branches off the costocervical artery (off the subclavian artery) and supplies the first three intercostal spaces dorsally
  

• White zone-- junction of wall epidermis with epidermis of the sole, ascending infections in this part of the hoof are called 'white line disease' or 'purulent hollow wall'
  

• Pulmonary ligament-- connects lungs to dorsal body wall, created by pleura reflecting off the caudal lung lobes
  

• Sternopericardial ligament-- connecs apex of the heart to the sternum and thereby provides positional stability for the heart; formed by a connective tissue band that is a continuation of the fibrous pericardium