Changes

==Histology==

==Histology==

[[Image:mucosal layer of colon.jpg|thumb|right|150px|Mucosal Layer of Colon (Fox) - © RVC 2008]]

[[Image:mucosal layer of colon.jpg|thumb|right|250px|Mucosal Layer of Colon (Fox) - © RVC 2008]]

*The mucosa of the large intestine is smooth; there are '''no villi or microvilli'''.

The mucosa of the large intestine is smooth; there are '''no villi or microvilli'''. The '''mucosal glands''' are much longer and straighter. The number of goblet cells in the mucosa is increased compared to the [[Small Intestine Overview - Anatomy & Physiology|small intestine]] as mucus is very important for lubrication of the ingesta as it passes through the intestine, particularly as more water is absorbed from the lumen making chyme drier.

*Mucosal glands are much longer and straighter.

 

*The number of goblet cells in the mucosa is increased compared to the [[Small Intestine Overview - Anatomy & Physiology|small intestine]].

There are numerous scattered lymph nodules in the large intestine. The number of lymph nodules increases compared to the [[Small Intestine Overview - Anatomy & Physiology|small intestine]]. The '''submucosa''' is also much reduced in thickness.

**Mucus is very important for lubrication of the ingesta as it passes through the intestine, particularly as more water is absorbed from the lumen making chyme drier.

 

*There are numerous scattered lymph nodules.

'''Taenia''' may be present. These are concentrations of the '''longitudinal muscle''' layer into long bands. When the taenia contract, they cause shortening of the large intestine, which produces saccualtions, or '''haustra'''. Haustra help to mix the content and to slow the transit time. Many glands are present in the mucosa and skin of the anal region.

**The number of lymph nodules increases compared to the [[Small Intestine Overview - Anatomy & Physiology|small intestine]].

*The submucosa is much reduced in thickness.

*'''Taenia''' may be present.

**These are concentrations of the longitudinal muscle layer into long bands.

**When the taenia contract, they cause shortening of the large intestine, which produces saccualtions, or '''haustra'''.

***Haustra help to mix the content and to slow the transit time

*Many glands are present in the mucosa and skin of the anal region.

==Species Differences==

==Species Differences==