> ![](media/image1.png){width="2.25in"
> height="2.0027777777777778in"}**COOL COWS, DYNAMITE DAIRY**
>
> In this exhibit from our Animal Improvement Programs Laboratory,
> students will explore how cows have been bred to produce large volumes
> of one of our most important food sources: milk. Hands-on activities
> include discovering how dairy breeds differ (match game), how genes
> influence the way that a cow looks and produces (pedigree charts), how
> cows are taken care of on modern farms (milking machine
> demonstration), and how dairy products differ ("play food").

**Primary Take-Home Message**

-   Cows contribute to our everyday welfare because they produce a
    high-quality food at a reasonable price.

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-   The genes (DNA) that calves receive from their parents affect the
    way that they look and how many gallons of milk they can produce
    each day.

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-   Foods made from milk (dairy products) can look very different
    (cheese, butter, yogurt, ice cream).

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-   Milk and dairy products improve the quality of the American diet.

**Ideas for In-Class Preparation**

-   Familiarize class with vocabulary words (attached).

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-   Familiarize class with dairy cattle breeds (teacher overview
    attached).

-   Familiarize class with basics of genetic inheritance (teacher
    overview attached).

-   Familiarize class with structure of modern dairy farm (teacher
    overview attached).

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-   Familiarize class with milk processing (teacher overview attached).

-   Familiarize class with different kinds of dairy foods (teacher
    overview attached).

> Over...

**Ideas for Follow Up**

-   Virtual field trip ("The Story of Milk" --
    http://www.moomilk.com/tour.htm)

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-   Coloring page (attached)

-   Word scramble (attached)

-   Spelling quiz on vocabulary words

-   In-class activity ("Make Butter" --
    http://webexhibits.org/butter/doityourself.html)

-   AIPL Kid's Corner (http://aipl.arsusda.gov/kc/kcindex.html)

**COOL COWS, DYNAMITE DAIRY**

**Vocabulary**

**Barn** -- Building where farm animals, their food, and farm equipment
are kept

**Bovine** -- Anything related to cows

**Breed** -- Group of animals that differ from related kinds of animals

**Bulk tank** -- Refrigerated tank at the farm in which milk is cooled
quickly and stored until picked up to be taken to the processing plant

**Bull** -- Adult male of cattle

**Butter** -- Solid, yellow, fatty food made by churning milk or cream

**Calf (*plural,* calves)** -- Young bovine, can be either male or
female

**Cattle** -- Bovine animals kept on a farm; refers to more than one
animal and can be either male or female

**Cheese** -- Food made from milk usually by removing the whey and
molding or flavoring the remaining curd

**Cow** - Adult female of cattle

**Cream** -- Yellowish part of milk that has the fat

**Curd** -- Solid part of milk after it has soured and thickened

**Dairy** -- Anything related to animals raised to produce milk and
foods made from milk

**Feed** -- Food for farm animals, usually a mixture

**Fodder** -- Coarse, dry food for farm animals

**Forage** -- Food (pasture) for grazing animals

**Gene** -- DNA that controls or influences how a bodily trait or
activity (such as coat color, height, milk yield) is inherited

**Genetics** -- Branch of biology that deals with inherited traits and
how they are different

**Grain** -- Seeds or kernels from various cereal plants (such as wheat,
oats, and corn); an important food for farm animals

**Graze** -- To feed on growing forage

> Over...

**Heifer** -- Young cow; especially one that has not had a calf

**Herd** -- Group of cows that live together

**Heredity** -- Passing of genes and genetic traits from parent to
offspring

**Homogenization** -- Pressurization of milk so that the fat does not
separate out

**Horn** -- Hard, boney growth on the head of cattle (usually in pairs)

**Ice cream** -- Frozen dairy food that has sweetened and flavored cream

**Lactation** -- Process of giving milk

**Livestock** -- Farm animals

**Low-fat milk** -- Milk that has part of the fat removed (also called
reduced-fat milk)

**Milk** -- Whitish liquid made by female mammals as food for their
young

**Milker** -- Person who milks cows

**Milking machine** -- Machine that takes milk out of the cow's udder

**Milking parlor** -- Building where dairy cows are brought specifically
to be milked

**Pasture** -- Land used for grazing

**Pasteurization** -- Heating milk to a high temperature to kill
disease-causing bacteria

**Pedigree** -- Chart or list that shows the line of ancestors (such as
parents or grandparents)

**Polled** -- Having no horns

**Raw milk** -- Milk as it comes from the cow before processing

**Silage** -- Fodder (such as hay or corn) that is broken down without
air (usually in a silo) to make rich moist food for farm animals

**Silo** -- Trench, pit, or especially a tall cylinder used for making
and storing silage

**Skim milk** -- Milk from which the fat has been removed

**Teat --** Part of the udder through which milk is drawn

**Trait** -- Quality or characteristic that differs

**Whey** -- Watery part of milk after it has soured and thickened

**Yogurt** -- Partially solid milk that has been soured by bacteria

![](media/image1.png){width="1.25in" height="1.1125in"}**COOL COWS,
DYNAMITE DAIRY**

**6 Major Breeds of U.S. Dairy Cattle**

**Holstein (93%):** The Holstein breed began in Holland (Netherlands)
and was brought to the United States in 1852. Holsteins are large cows
with spotted patterns of black-and-white or red-and-white. A Holstein
calf weighs about 90 pounds at birth, and an adult Holstein cow weighs
about 1,500 pounds. Holsteins give the most milk per cow of all breeds
(an average of 61 pounds or 7½ gallons per day). One top producing
Holstein cow averaged over 24 gallons of milk per day. The milk is 3.6%
fat and 3.0% protein. Holsteins are the most popular dairy breed in the
United States, and 9 of every 10 U.S. dairy farmers currently milk
Holsteins.

**Jersey (5%):** This breed started on the Isle of Jersey, a small
island in the English Channel, and was brought to the United States
during the 1850s. Jerseys are the smallest dairy cows. Calves weigh
about 60 pounds at birth, and adult cows weigh approximately 900 pounds.
The coat color is brown that can vary from very light beige (fawn) to
almost black. Some Jerseys have white markings or spots. Both bulls and
cows are usually darker around the hips, head, and shoulders. Daily milk
yield for an average Jersey cow is 44 pounds (5¼ gallons). Because the
milk is high in fat (4.6%) and protein (3.6%), it is preferred for
making cheese and butter.

**Brown Swiss (1%):** The Brown Swiss breed began in Switzerland and is
thought to be the oldest of the dairy breeds. Brown Swiss cows were
brought to the United States in 1869. Brown Swiss are large cows, about
the same size as Holsteins. The color of Brown Swiss varies from light
brown to gray. Some calves are born almost white and later change to
their adult color. Brown Swiss cattle are noted for their strong feet
and legs, long lives, and quiet temperament. The gestation length (time
that the cow is pregnant) is 9 months and 16 days, which is 10 days
longer than for other dairy breeds. Daily milk yield per cow averages 49
pounds (5¾ gallons). Milk from Brown Swiss cows has moderate fat (4.0%)
and high protein (3.4%) content and also is valued for making cheese.

> Over...

**Guernsey (\<1%):** The Guernsey breed started on the Isle of Guernsey,
another island in the English Channel, around 960 A.D. and was brought
to the United States around 1840. Guernsey cows are medium-sized (about
1,200 pounds) and have brown-and white spots. The brown color can be
light golden brown to nearly mahogany. Daily milk yield per cow averages
41 pounds (5 gallons) with 4.5% fat and 3.4% protein. The milk often is
referred to as "the golden product" because of its yellow butterfat
content.

**Ayrshire (\<1%):** This breed started in the county of Ayr in Scotland
and was brought to the United States around 1832. Ayrshires are
medium-sized (adult cows weigh about 1,200 pounds) with red-and-white
spots. The red color varies from light mahogany to nearly black. The
spots are usually jagged and small, sometimes even speckled. Daily milk
yield of Ayrshire cows averages 43 pounds (5¼ gallons) with 3.8% fat and
3.2% protein. Ayrshire cattle are noted for their hardiness and
excellent foraging ability. Most Ayrshires in the United States can be
found in the colder climates of the Northeast and Midwest states.

**Milking Shorthorn (\<1%):** One of the oldest recognized breeds in the
world, Shorthorn cattle originated in northeastern England and were
brought to the United States in 1783. Shorthorns provided milk, meat,
and transportation for many American pioneers. The Milking Shorthorn is
not a separate and distinct breed but a segment of the Shorthorn breed,
which also includes Beef Shorthorns. Milking Shorthorns are medium-sized
(adult cows weigh about 1300 pounds) and either a shade of red, white,
red-and-white spots, or roan (a mixture of red and white hairs). These
docile cows average 39 pounds (4¾ gallons) of milk daily with 3.6% fat
and 3.1% protein and are large enough to have considerable beef value
when their long productive lives end.

![](media/image1.png){width="1.25in" height="1.1125in"}**COOL COWS,
DYNAMITE DAIRY**

**Understanding Genetics**

**Heredity:** An animal (or a person) often looks a lot like one or both
of its parents because of the genes (DNA) that are passed along from the
father and mother to the animal. For example, kittens grow up to look
like cats, and calves grow up to look like cattle. Genes influence how
all the traits of an animal are expressed, sometimes directly and
strongly (for example, coat and eye color, height, or weight) ... and
other times indirectly or in combination with other genes (for example,
how much milk a cow produces, the composition of the milk, or how well
the cow resists disease). Because traits are influenced by genes, the
appearance or behavior of animals can be changed by choosing animals
with the features you consider most desirable to be parents of the next
generation of animals. Genetic change is permanent and adds up over
time.

[GENETIC INHERITANCE -- Why does a cow look (or not look) like its
parents?](../genetic_inheritance.ppt)

**Gene expression:** Genes work in pairs. Sometimes each gene has an
equal influence on how a trait is expressed, but many times one gene is
dominant over the other (recessive) gene in determining the trait. For
example, whether or not a cow has horns is controlled by a
dominant-recessive pair of genes. The gene for no horns (polled) is
dominant, and the gene for horns is recessive. A cow with 2 "polled"
genes will have no horns. A cow with 2 "horned" genes will have horns. A
cow with 1 polled gene and 1 horned gene will not have horns because the
horned gene is recessive and the polled gene is dominant.

**Genetic evaluations:** Differences between individual animals that can
be passed on to future generations (inherited) can be measured through
genetic evaluation. How a calf will look or produce can be estimated
(scientifically guessed) by looking at an animal's pedigree (ancestor
chart) to see how its ancestors looked or produced, When the calf grows
up, its own appearance and ability to give milk can be used to provide
more information on how its genetics can be passed to its calves.
Genetic evaluations are important for choosing parents with superior
genes for traits of interest (such as milk production or long life).

![](media/image1.png){width="1.25in" height="1.1125in"}**COOL COWS,
DYNAMITE DAIRY**

**Today's Dairy Farm**

**Housing:** Many of today's modern dairy farms use "free stall
housing," which is a type of barn that allows cows to eat and sleep
whenever and wherever they choose. Dairy cows always have access to feed
and fresh, clean water. Farmers ensure that their cows have room to lie
down, stretch, eat, and drink comfortably. Many dairy farmers have
installed rubber or other non-slip flooring in their barns to make it
easier for the cows to move around. Cows may sleep on waterbeds, sand
beds or mattresses made of rubber, foam or a combination of the two.
Most dairy barns use advanced ventilation systems to assure healthy air
quality. On warm days, farmers use fans and misters to make cows feel
cool and comfortable.

**Feed:** Farmers use professional nutritionists to develop a
scientifically nutritious diet for their cows. This diet is called a
total mixed ration and includes hay (such as alfalfa and timothy),
silage, grains (such as wheat, oats, and corn), protein sources (such as
soy) and other vitamins, minerals, and fats. Cows eat from 40 to 80
pounds of food a day and are fed up to 8 times a day. Electrically
operated feeders and mixer wagons make feeding quicker and easier. Cows
drink 30 to 40 gallons (about a bathtub full) of water each day. A cow
must drink 2 gallons of water for every gallon of milk that she gives.

**Milking:** Before milking machines were invented in 1894, farmers
could only milk about 6 cows per hour. Today farmers use machines that
work on vacuum pressure to milk more than 100 cows per hour. Cows
usually are milked by machine 2 or 3 times each day. The building where
cows are milked is called a milking parlor. After a cow enters the
parlor, her udder is washed to keep the milk clean and to signal the cow
to "let down" her milk. A milking machine with 4 teat cups is attached
to the cow, and the milk is cooled and pumped into a large storage tank
(bulk tank).

![](media/image1.png){width="1.25in" height="1.1125in"}**COOL COWS,
DYNAMITE DAIRY**

**Milk Processing --- From Farm to Store**

**History:** In 1841, the first regular railway shipment of milk was
started from Orange County, NY, to New York City. Milk condensing and
pasteurization (process of heating milk to a high temperature to kill
bacteria) were invented in 1856 to combat food poisoning and other
illnesses related to lack of refrigeration and preservation techniques.
Refrigeration became available in the 1880s. Homogenized milk premiered
successfully in 1919; homogenization is the process of pressurizing milk
so that the fat does not separate out. Today milk gets from the cow to
the store in about 2 days.

**On the farm:** Raw milk is cooled to 38˚F and is stored in
refrigerated storage tanks. A tanker truck comes to pick up the milk
daily and take it to the processing plant. The truck driver tests the
milk before pumping it into the truck to make sure that it\'s safe to
drink. Each truck is insulated and acts like a giant thermos bottle to
keep the milk cool until it reaches the processing plant.

**At the processing plant:** Raw milk is checked again at the plant to
make sure that it's safe to drink and then pumped from the milk truck
into a storage tank. Then the milk is homogenized and pasteurized. Milk
also is fortified with vitamin D (and vitamin A for lowfat and skim
milk) to make it even more healthful. Dairy processing plants make
different types of milk, ice cream, cheese, yogurt, butter, and other
dairy products.

**At the store:** At the grocery store, milk is kept refrigerated at
40˚F or lower. When kept refrigerated at that temperature, milk should
last approximately 7 days past the sell-by date on the container. A 5°F
increase in storage temperature shortens milk's shelf life by 50%.

![](media/image1.png){width="1.25in" height="1.1125in"}**COOL COWS,
DYNAMITE DAIRY**

**Dairy Foods --- Milk, Butter, Cheese,**

> **Yogurt, Ice Cream**

**Milk:** Whole milk is about 87% water, 5% lactose (milk sugar), and 8%
protein, fat, vitamins, minerals. A gallon of milk weighs a little more
than 8½ pounds. Each serving of milk provides 10% or more of the
recommended daily intake for calcium, vitamin D (if fortified), protein,
potassium, vitamin A, vitamin B12, riboflavin. and phosphorus. The
average American drinks about 22 gallons of milk each year, and 99% of
all U.S. households buy milk. Fluid milk sales account for 32% of total
U.S. milk consumption. Low-fat milk is about 2/3 of total milk
consumption. Nonfat dry milk accounts for 4% of the milk consumed in the
United States. It takes 7 pounds (a little more than 3 quarts) of fluid
milk to make 1 pound of nonfat dry milk. California is the top
milk-producing State.

**Butter:** Butter is made from milk, cream, or both (with or without
common salt) and contains at least 80% fat. Fresh cream is churned until
the fats separate from the liquid (buttermilk). Americans consume more
than 4 pounds of butter per person per year. Butter accounts for 13% of
U.S. milk consumption. Making 1 pound of butter takes 21 pounds (almost
2½ gallons) of whole milk. California is the top butter-producing State.

**Cheese:** All cheese is made from milk, but different manufacturing
and aging

processes are used to produce different kinds of cheeses. Cheese is made
by curdling milk, stirring and heating the curd, draining off the whey
(the watery part of milk), collecting and pressing the curd, and in some
cases, ripening. About 1/3 of all milk produced each year in the United
States is used to make cheese. Making 1 pound of cheddar cheese takes 10
pounds (almost 5 quarts) of milk. The most commonly produced cheeses in
the United States are cheddar (34%), mozzarella (33%), and American
(8%). Wisconsin is the top cheese-producing State.

> Over...

**Yogurt:** Yogurt is a mixture of milk and cream fermented by bacteria.
Sometimes sweeteners (sugar, honey, aspartame), flavorings (vanilla,
coffee), and other ingredients (fruits, nuts, jams) may be added to
yogurt. Making 8 ounces of yogurt (1 cup) takes 1 pound (about 1 pint)
of milk. California is the top yogurt-producing State.

**Ice Cream/Frozen Yogurt:** Historians estimate that ice cream evolved
sometime during the 16th century in Italy, perhaps from a recipe Marco
Polo brought from the Orient. The hand-crank freezer, which was patented
in 1846, led to the establishment of the first commercial ice cream
plant in Baltimore in 1851. Ice cream is made by stirring (while
freezing) a mix of milk (or cream), sweeteners, and flavorings. It takes
13 pounds (1½ gallons) of milk to make ½ gallon of ice cream. Frozen
products account for 7% of U.S. dairy consumption. Frozen yogurt was
introduced in the late 1960s and is made like ice cream but with the
addition of bacteria that are used to make yogurt. The average American
eats about 5½ gallons of ice cream each year, and 93% of U.S. households
eat ice cream. California is the top ice cream-producing State.

**COOL COWS, DYNAMITE DAIRY**

**Dairy Breeds Coloring Page**

Color each cow the correct color for the breed name under the cow. Add
spots if needed.

![](media/image2.png){width="3.629861111111111in"
height="2.5027777777777778in"}

**Holstein**

![](media/image2.png){width="3.629861111111111in"
height="2.5027777777777778in"}**Brown Swiss**

![](media/image2.png){width="3.4097222222222223in"
height="2.3506944444444446in"}**Ayrshire**

**Jersey**

![](media/image2.png){width="3.479861111111111in"
height="2.3993055555555554in"}**Guernsey**

![](media/image2.png){width="3.4097222222222223in"
height="2.3506944444444446in"}**Milking Shorthorn**

**COOL COWS, DYNAMITE DAIRY**

**Super Scramble**

Try a few ... or do them all! They're all about cows and dairy products.

**ydira**

**deber**

**curd**

**zagre**

**ratti**

**gilsea**

**wsoc**

**sonhr**

**gotruy**

**taclet**

**oils**

**yhew**

**rehfie**

**narb**

**tubtre**

**macer**

**fegaor**

**owl-aft ilmk**

**dityrehe**

**zestiarunopiat**

**edrh**

**kinglim nichame**

**cie rcmea**

**reddof**

**lfac**

**esehce**

**setenicg**

**gomohenniozati**

**saperut**

**lubls**

**stockevil**

**giran**

**COOL COWS, DYNAMITE DAIRY**

**Super Scramble ANSWERS**

**ydira ... DAIRY**

**deber ... BREED**

**durc ... CURD**

**zagre ... GRAZE**

**ratti ... TRAIT**

**gilsea ... SILAGE**

**wsoc ... COWS**

**sonhr ... HORNS**

**gotruy ... YOGURT**

**taclet ... CATTLE**

**oils ... SILO**

**yhew ... WHEY**

**rehfie ... HEIFER**

**narb ... BARN**

**tubtre ... BUTTER**

**macer ... CREAM**

**fegaor ... FORAGE**

**owl-aft ilmk ... LOW-FAT MILK**

**dityrehe ... HEREDITY**

**zestiarunopiat ... PASTEURIZATION**

**edrh ... HERD**

**kinglim nichame ... MILKING MACHINE**

**cie rcmea ... ICE CREAM**

**reddof ... FODDER**

**lfac ... CALF**

**esehce ... CHEESE**

**setenicg ... GENETICS**

**gomohenniozati ... HOMOGENIZATION**

**saperut ... PASTURE**

**lubls ... BULLS**

**stockevil ... LIVESTOCK**

**giran ... GRAIN**