Animal Body Systems in Production Species: Structure, Function, and Growth

Dorsal

Toward the back (topline).

Ventral

Toward the belly/underline.

Cranial

Toward the head.

Caudal

Toward the tail.

Medial

Toward the midline.

Lateral

Away from the midline.

Proximal

Closer to the body.

Distal

Farther from the body.

Muzzle/Snout

Involved in prehension, breathing, and sensing.

Nostrils (Nares)

Airflow; can flare dramatically during exertion.

Withers

Bony ridge at the base of the neck in horses.

Udder

Milk production and delivery in female mammals.

Hoof/Claw

Protects distal bone and soft tissue; important for locomotion.

Cloven hoof

A hoof with two primary digits (claws) in ruminants.

Rumen

A large fermentation vat in ruminants for breaking down cellulose.

Cecum

The site of fermentation in hindgut fermenters like horses.

Proventriculus

Glandular stomach in birds for chemical digestion.

Gizzard

Muscular grinding organ in birds for mechanical digestion.

Osteoblasts

Cells that build bone.

Osteoclasts

Cells that break down bone.

Epiphyseal plates

Growth plates where bone lengthening occurs.

Skeletal muscle

Striated muscle mostly under voluntary control.

Spermatogenesis

The process of sperm production in the testes.

Estrogen

Hormone produced by ovaries; associated with estrus behavior.

Testosterone

Hormone produced by testes; supports sperm production.

Negative feedback

Process where the product of a pathway reduces its own production.

Homeostasis

Maintaining stable internal conditions despite external changes.