Dairy Cattle Science and Management

Key vocabulary and terms regarding dairy cow life cycles, breeds, vital signs, behavior, vision, and haltering procedures.

Early Lactation

The stage occurring from 14 to 100 days post-calving where milk production peaks and cows may lose weight due to a negative energy balance.

Mid Lactation

The stage occurring from 100 to 200 days post-calving where milk production is maintained and dry matter intake (DMI) should reach $4\%$ of body weight.

Late Lactation

The stage occurring from 200 to 305 days post-calving where milk production and dry matter intake decrease while the cow gains weight.

Dry Period

A $45 - 60\,\text{day}$ period before calving during which cows are not milked.

Holstein

A black and white dairy breed known for high milk production (approx. $25,000\,\text{lbs/yr}$) that comprises about $90\%$ of all dairy cows in the US.

Jersey

A light to dark brown dairy breed known for high quality milk with increased fat ($4.58\%$) and protein ($3.57\%$) components and high heat tolerance.

Brown Swiss

A silver to dark-brown dairy breed known as the 'draft dairy cow' and considered one of the oldest dairy breeds.

Guernsey

A dairy breed originating from the island of Guernsey whose milk has a golden color due to high levels of beta carotene.

Ayrshire

A rusty-red or reddish-brown and white dairy breed recognized as an efficient grazer with mid-range fat and protein levels.

Milking Shorthorn

A red or roan and white dual-purpose dairy breed developed from the Shorthorn breed with grazing advantages.

Flight Zone

The boundary around an animal that triggers a movement response when entered by a handler.

Point of Balance

The imaginary line at a cow's shoulder used to direct movement; moving behind it encourages forward movement, while standing in front causes stopping or turning.

Binocular Vision (Cattle)

Vision spanning a $25 - 50^{\circ}$ arc directly in front of the cow that provides depth perception.

Fixed Nose Band (Halter)

The short, immovable section of a halter (coded blue) designed to sit on top of the animal's nose.

Quick-Release Knot

A knot used to restrain cattle that tightens if the animal pulls back, but unties rapidly when a handler pulls the free end.