Companat: Digestive

Q

A

What explains differences in digestive systems among species?

Dietary adaptation and evolutionary specialization

Why is comparative digestive anatomy important in veterinary medicine?

It aids diagnosis

Which species are being compared in this topic?

Birds

Which species are monogastric?

Dog

Which species are foregut fermenters?

Ruminants

Which species have a modified monogastric system?

Birds

What characterizes carnivore GI tracts?

Short

Where do ruminants ferment fiber?

Forestomachs

Where do horses ferment fiber?

Cecum and colon

What avian organs replace mastication?

Crop

What structure replaces teeth in birds?

Beak (rhamphotheca)

Do birds masticate food?

No

Which birds have rough tongues?

Seed eaters

Which birds have filtering papillae on the tongue?

Waterfowl

What are dog carnassial teeth?

P4 and M1

What is the tongue surface of cats like?

Keratinized filiform papillae forming a rasping surface

What do ruminants lack in the upper jaw?

Upper incisors

What replaces upper incisors in ruminants?

Dental pad

Which species use a prehensile tongue for food intake?

Cattle

Which species use mobile lips for food intake?

Small ruminants

What type of teeth do horses have?

Hypsodont

Why is efficient mastication important in horses?

Prevents colic

What is the avian crop?

Storage diverticulum of the esophagus

What type of epithelium lines the avian crop?

Stratified squamous epithelium

Which animals have a fully striated esophagus?

Dogs

What is the muscle distribution in the cat esophagus?

Proximal two-thirds striated

What esophageal feature enables rumination in ruminants?

Thick muscular wall

Why are horses unable to vomit?

Strong cardiac sphincter

Why are horses prone to choke?

Esophagus mainly smooth muscle

What is the glandular stomach of birds?

Proventriculus

What does the proventriculus secrete?

HCl and pepsinogen

What is the muscular stomach of birds?

Ventriculus or gizzard

What aids grinding in the gizzard?

Grit

What protects the gizzard mucosa?

Koilin layer

What type of stomach do dogs have?

Simple monogastric

Why is the dog stomach highly distensible?

Carnivores need large food storage

How does the cat stomach compare to the dog stomach?

Smaller and more acidic

What are the four ruminant stomach compartments?

rumen, reticulum, abomasum, omasum

What is the function of the rumen?

Anaerobic fermentation and VFA absorption

What lines the rumen for absorption?

Papillae

What is the structure of the reticulum mucosa?

Honeycomb pattern

What disease is associated with the reticulum?

Hardware disease

What is the primary function of the omasum?

Absorption of water and VFAs

What is the abomasum equivalent to?

Monogastric stomach

What percent of the horse GI capacity is the stomach?

About 10 percent

What divides the horse stomach?

Margo plicatus

Why are horses prone to gastric ulcers?

Large non-glandular region

Which species have the shortest small intestine?

Dogs and cats

Which species has a narrow long small intestine and is prone to strangulation?

Horse

What marks the midgut in birds?

Meckel diverticulum

How many ceca do birds have?

Two

What are the three chambers of the cloaca?

Coprodeum

How large is the dog cecum?

Small

How large is the cat cecum?

Very small

What characterizes the cat colon?

Short

How large is the cattle cecum?

Large

What is the structure of the ruminant colon?

Spiral colon

What is the horse's main fermentation site?

Cecum and colon

How large is the horse cecum?

About 30 liters

What is the order of the horse large colon parts?

Right ventral

Where are fecal balls formed in the horse?

Small colon

Where does fermentation occur in ruminants?

Rumen

Where does fermentation occur in horses?

Cecum and colon

Which species have minimal fermentation?

Dogs and cats

Why is digestion rapid in carnivores?

Simple GI tract

What replaces teeth in mechanical digestion in birds?

Gizzard

Why do horses risk colic when dental problems occur?

Saliva released only during chewing

What life-threatening gastric condition occurs in deep-chested dogs?

GDV

What GI issue is common in dogs and cats?

Foreign body obstruction

What are the two types of ruminant bloat?

Frothy and free-gas

What disease results from swallowed metal in ruminants?

Hardware disease

What displacement occurs in dairy cattle?

Left displaced abomasum

What is the major GI syndrome in horses?

Colic

Why are horses prone to choke?

Narrow esophagus

What avian condition involves a yeast infection of the crop?

Sour crop

What viral disease causes nerve dysfunction in parrots?

Proventricular dilatation disease