Comparative Digestion Systems & Processes

Modified by Ashlee Gibson

The Digestion Process

• Food is broken down• Animals have digestive systems adapted to the

foods that they consume• Four types of digestive systems

– _____________________________________– _____________________________________– _____________________________________– ______________________________________

Ruminant Digestive System

Modified to handle the breakdown of large amounts of

_________________

Ruminant Digestive System

• Mouth– no upper ___________________, hard palate– molars for grinding coarse vegetation– saliva does not contain ___________________

• _______________________________– muscular tube connecting the mouth to the

stomach

Ruminant Digestive SystemsThe Four Compartmented Stomach

• Rumen: storage area and _______________________________

• Reticulum: nails and wire may be found here-_____________________ stomach

• Omasum: eliminates excess ___________from feed

• Abomasum: true stomach, _____________ and __________________ are secreted

Ruminant Digestive Systems

Stomach (cont.)• _______________: first step in rumination

– large quantities of roughage are consumed and are chewed just enough to swallow

– after swallowing, regurgitation (“cud chewing”) takes place, food is re-chewed

Ruminant Digestive System

• Small Intestine– connects stomach to large intestine– ______________________________________– contains bile and pancreatic juices– pushes food through by muscle contractions

Ruminant Digestive System

• Large Intestine– Contains Cecum, Colon and Rectum

• ____________________: sac at junction of small intestine and large intestine

• Colon and rectum: at end of system– not as long as small intestine, but larger in

diameter– water and some nutrient absorption occurs here– where residue solidifies before excretion

Monogastric Digestive System

Characterized by inability to digest roughage efficiently

Monogastric Digestive System

• Mouth– has upper and lower incisors– ________________________ secreted which

breaks down nutrients• Esophagus

– connects mouth to stomach

Monogastric Digestive System

• Stomach – secretes _________________________ to

break down nutrients– enzymes such as ______________ also

secreted here– churning action mixes food

• Small and Large Intestine• function just as in ruminant systems

Avian Digestive Systems

Characterized by several organs not found in other species that are

adapted for grinding hard or encased food

Avian Digestive Systems

• Mouth – ____________________________________– Salivation excretion ____________________

• Esophagus – has a modification called the _____________

which stores and moistens food– connects mouth and stomach

Avian Digestive Systems

• Stomach– Contains two parts

• _______________________________: same as monogastric stomach and provides digestive excretions

• _______________________________: located after proventriculus, very muscular, used to grind food

Avian Digestive Systems• Small Intestine

– similar functions as in ruminants and monogastric systems• Large Intestine

– similar functions as in ruminants and monogastric systems– _____________________ chamber into which urinary and

genital canals open– ___________________ aids in fiber digestion and

absorption

Equine Digestive Systems

Characterized by non-ruminant animals that consume and digest

feeds high in fiber

Equine Digestive Systems

• Mouth – intact top and bottom incisors– molars adapted to chewing fibrous feeds– no digestive enzymes in saliva

• Esophagus– not well adapted for _____________________– connects mouth and stomach

Equine Digestive System

• Stomach– similar to monogastric system

• Small intestine– similar to monogastric and ruminant systems– ____________________ to store bile – enlarged _______________ to aid in fiber

breakdown

Equine Digestive System

• Large Intestine – similar to monogastric systems– _________________________ (at junction of

small and large intestines) and colon take up most of the volume of the equine digestive system