Equine Digestive Tract Anatomy: hindgut Flashcards
rate of passage factors
quantity and physical quality of food impacts speed
why does discreet feeding have a bad impact on rate of passage?
it increases intake in a short period of time, so food passes through quickly and nutrients aren’t absorbed, leading to more fermentation
the cecum has a homeostatic neutral pH
true
what happens to the pH of the cecum if carbohydrate intake is increased?
more carbohydrates increase rate of passage and cause lots of carbohydrates to end up in the cecum where more acidic fermentation products are produced causing a lower acidic pH in the cecum
where does the hindgut begin?
the ileocecal junction
why is the ileocecal valve important?
it is a functional valve that causes feed to move one way and prevents backflow of digesta back into the ileum
The large intestine is larger and more anatomically complex in horses
true
hindgut components
cecum, large colon, small colon, and rectum
hindgut volume
accounts for 61% volume of the intestinal tract
hindgut rate of passage
slow, 35 hour average
cecum also known as
blind sac
cecum function
primary site for microbial fermentation, 35 liter capacity
cecum characteristics
holds undigested feeds and contents enter and exit from the top
cecum anatomy
large comma shaped organ, base occupies the right flank but extends forward
cecum contractions
alternating contractions that mix and move digesta, haustra alternately contract and expand
what are the haustra of the cecum?
small pouches caused by sacculation
large colon also known as
ascending colon
large colon size
diameter average 8-10” and 80 liter capacity
large colon anatomy
folded together to form a double loop, left and right ventral and dorsal loops
large colon function
efficiently mix digetsa through persaltic and antiperistaltic movement
what is absorbed in the large intestine?
water, electrolytes, B vitamins and volatile fatty acids
volatile fatty acids
contribute more than 60% of energy content needed, lipid soluble to move easily across membranes and be absorbed by the hindgut
water
most water is absorbed in the foregut, but the hindgut provides a reservoir to pull water out of when dehydration occurs
electrolytes
sodium and potassium are absorbed in the hindgut
B vitamins
made from bacteria, water soluble to be absorbed in the hindgut
large colon rate of passage
2-3 days
large colon vulnerability
due to its anatomy, the large colon is vulnerable to twisting and gas buildup when nutrient flow is abnormal
why is the large colon anatomy vulnerable?
the diameter of different segments changes abruptly and the large colon has several flexures
small colon anatomy
consists of transverse and descending colon, contains pouches called sacculations that aid in forming fecal balls
sacculations
form fecal balls by absorbing water and compacting feces
rectum
terminal portion of the hindgut upon entering the pelvic inlet, opens to the exterior at the anus
rectum innervation
sympathetic and voluntary nervous systems, has a voluntary sphincter
