Exam Two: Ruminant Digestion Vocabulary

Twenty vocabulary flashcards covering key concepts of rumen fermentation and ruminant digestion.

Ruminants

Animals with a multi-chamber foregut that supports fermentation (e.g., cattle, sheep, deer).

Rumen

The large fermentation chamber of the ruminant stomach where feed is stored and microbes break down polysaccharides.

Fermentation

The microbial process that converts large carbohydrates (cellulose, amylose) into volatile fatty acids in the rumen.

Anaerobic bacteria

Bacteria that require no oxygen; thrive in the rumen and drive fermentation.

Cellulose

A major plant polysaccharide in forages; substrate for cellulolytic bacteria.

Amylose

A form of starch; substrate for amylolytic bacteria in the rumen.

Cellulolytic bacteria

Bacteria that break down cellulose in the rumen; anaerobic.

Amylolytic bacteria

Bacteria that break down amylose/starch to VFAs; anaerobic.

Volatile fatty acids (VFAs)

Energy-rich end products of rumen fermentation used by the host animal.

Acetic acid

A two-carbon volatile fatty acid produced in the rumen; among the main VFAs.

Propionic acid

A three-carbon volatile fatty acid produced in the rumen; a major energy source.

Butyric acid

A four-carbon volatile fatty acid produced in the rumen; an energy source.

Bicarbonate

A buffering component in saliva that helps maintain rumen pH by neutralizing acid.

Ruminal pH

Normal rumen pH approximately 6.2–6.8 to keep bacteria alive and fermentative activity optimal.

Stomach pH

Gastric pH around 2.5; acidic environment that kills most bacteria.

Keratinized tongue

Ruminant tongue, especially cattle, rich in keratin; gives stiffness and durability.

Upper incisors absent

Ruminants lack upper incisors; use a hard palate to crop vegetation.

Saliva production

Cattle produce roughly 40–50 gallons of saliva per day, providing bicarbonate for buffering.

Four chambers, not four stomachs

Ruminant stomach has four compartments within one stomach rather than four separate stomachs.

End products of fermentation

VFAs produced by rumen bacteria; used by the animal as a primary energy source.