They're Bos-sy


Bos taurus

Domestic Cow

University of Wisconsin-La Crosse


Introduction           Classification        Habitat        Phylogenetic Tree

Adaptations        Nutrition       Reproduction        Interactions with other Species

Disease       Behaviors       History of Milk      Fun Facts      References     



Picture taken by myself


The Life and Times of Bos taurus:

                    Bos taurus is a descendent of wild cattle including bantengs, gaur, yaks, and water buffalo. The species is made up of several hundred different breeds. They weigh approximately 147-1363 kilograms, and are about 49-52 inches in height. The color varies from black, white, brown, and reddish brown. Males have two hallow horns and females are about 20% smaller than males. They have no upper incisors.


How Do Cows Classify?

                         Domain: Eukarya

                        Kingdom: Animalia-- Multicellular, heterotroph

                        Phylum: Chordada- possess a notochord during development, three germ layers,

                                             bilateral symmetry

                        Class: Mammalia- middle ear bones, hair, mammary glands

                        Order: Artiogactyla- paraxonic

                        Family: Bovidae- horns on frontals, unguligrade, lack sagittal crests, four             

                                           chambered stomach, no upper incisors or canines

                        Genus: Bos- dewlaps, dental pad

                        Species: Bos taurusPicture taken by UW-L student, Jennifer Harguth- domestic cattle



Down on the Farm:

                    Cattle was first domesticated in the Middle East between 6000 and 5000 BC and then spread to Africa and Europe.  They are now found throughout all of the world besides Antarctica. Bos taurus is found in habitats where suitable food is available and there is native vegetation. Cattle are often born and raised on rangelands, which are unfertilized, uncultured, and not irrigated. They are found in a variety of habitats, such as temperate, tropical and terrestrial habitats. The terrestrial biomes that Bos taurus can be found are desert or dunes, savannas, grasslands, chaparral, forests, and scrub forests. The vast majority of Bos taurus are domesticated and can be found in agricultural areas.  Bos tarus can be found in every county in Wisconsin. There are about 1.3 million cows from this species found on 17,711 farms in Wisconsin (Dewey). It is the most widely distributed domestic animal in the state, and the population densities are largest in east central parts of the state. Densities are much lower in the southwest.

Family Tree:


How have cows adapted?

                Bos taurus have adapted in ways to help perceive the environment more efficiently including chemical signals, touch, vision and sounds. Cattle have evolutionarily adapted to regional environments resulting in Spring calving patterns and mating in the early summer. To conserve body heat, cattle have adapted by adjustments in behavior (seeking shade), evaporative heat loss (panting and sweating), and circulation of blood (vasodilatation). Cattle have the ability to adapt to changes in ambient temperature over short periods of time. The main mechanism by which this early adaptation is accomplished is by changes in the metabolic rate. Hide insulation also changes to favor conservation or depletion of heat. Cows have adapted to food availability with rumen digestion. This allows them to consume a wider variety of plants. More information about rumen digestion can be found in the "Nutrition" section. Many breeds of Bos taurus have been subjected to strong selection pressure for improved dairy and beef.

I'll have a small tree and a side of grass:

                Bos taurus are all herbivores, eating only plants. On average, cows take in thirty gallons of water and ninety-five pounds of food per day, spending about six hours a day eating and eight hours chewing cud. Cattle bulk graze on fresh grasses, shrubs, young trees and other succulent vegetation. They feed in an area until the food source is gone and then move on in search of more. In domestic cattle, grazing rotation systems are used to mimic nature and maintain a constant food source. It is also used to prevent damage to vegetation by overgrazing. Corn is the most popular feed of domestic cattle followed by pasture and then hay. Cows feed rapidly until their pouch is full and then alternate chewing cud with grazing throughout the day.

Picture taken by myself

                Cows are ruminants. They have a special system of digestion which allows for the breakdown of relatively indigestible plant material. All cattle have a four chambered stomach, consisting of a rumen, reticulum, omasum and abomasum. Grass is passed through the rumen and mixed with specialized bacteria. It then moves to the reticulum and is further broken down. This partially digested food, known as cud, is regurgitated, chewed and then swallowed. It then moves into the omasum and abodasum where digestive enzymes break it down further and nutrients are absorbed. The process of digestion takes about 70 to 100 hours. Cows have a closed circulatory system. Their blood stays in the blood vessels at all times, never coming into direct contact with other cells in the body.

                Bos taurus does have a few predators. Their wild ancestors were hunted by large carnivore including wolves, lions, bears, and humans. The main predator now is humans.

How to set the right moooooooooood:

                Cattle are sexually mature at about the age of thirteen months, and they usually breed at thirteen to twenty-six months. They breed in a natural settings and polygyny (males mating with more than one female) has been observed. Dominant males compete for the Picture taken by UWL student Jennifer Harguthfemales. They are dioecious, meaning male and female reproductive organs are in separate animals. Cows mate year round, but more calves are born in the spring. Fertilization and development take place within the female body and developing embryos get nourishment from the female. One calf is born after about nine months of gestation and the young are precocial, or relatively mature at birth. Cattle nurse for approximately six months. The maximum lifespan is more than twenty years, but the natural life span is generally not fulfilled. The average life is about three to four years before being sold for beef.

                Artificial insemination is often utilized in domestic cows. Eggs from prized cows are harvested and fertilized in a lab. Frozen embryos are then implanted in other cows or exported to cattle growing markets.


Are you my friend?

                Ecological interactions with other species includes grazing. Cows can severely impact natural systems by causing erosion, introduction of nonnative grasses and herbaceous plants, destruction of riparian habitats, and overgrazing. Browsing, crushing and trampling can severely modify native vegetation.

               Cows also interact with native animal species, mostly being predators. Grazers and young are the target of predators due to the abundance and large groups. Domestic cattle are easy targets for predators because they are peaceful and calm breeders and are not very cautious, making them very vulnerable.

                Bos taurus also interact with humans. They provide food, such as dairy products and meat, which is their major use to humans. They are also used for plowing and moving heavy loads. Leather, glue, soap and some medicines are all made with parts of the cow. Also, the dung provides fertilizer and fuel, they're often important culturally in other countries, and are used as currency in some countries.

    In the rumen, millions of bacteria and protozoan can be found. They produce enzymes that break down cellulose into starch and make amino acids, fermenting food and enabling the cow to obtain energy that would not otherwise be available. The bacteria make all B vitamins. It is a symbiotic relationship.

Crazy Cows:

                Bovine Spongiform Encephalopathy (BSE) or Mad Cow Disease is a fatal degenerative brain disease that affects the brain of cattle. Unique proteins called prions bond with the cow's brain cells altering the composition and leading to death. It was first discovered in the United Kingdom and researchers have traced the disease to farmers mixing dead sheep's neural tissue into the feed of cattle to save money. If infected cattle are eaten by humans, they will develop the human version of the disease known as Creutzfeldt-Jakob disease (nvCJD). This human version initially causes memory loss and erratic behavior, but eventually leads to death. The U.S. Department of Agriculture says there is not any Mad Cow Disease in U.S. cattle but admits it has only tested less than 200,000 cattle last year (PETA).

        Some other diseases Bos taurus experience are East Coast Fever (ECF) which is an acute, tick-borne disease causing high rates of morbidity and mortality in cattle, and Anaplasmosis which is a vector-borne, infectious blood disease. Brucellosis is an infection with the bacterium Brucella abortusof which causes abortion or premature calving. Bovine Virus Diarrhea is an infection that can cause damage to the digestive and immune systems, pneumonia, abortions, calf deformities, and others. Coccidiosis is caused by microscopic, one-celled parasites which leads to diarrhea, rough coat, loss of appetite and weight, and general emaciation. Infectious bovine rhinotracheitis , or red nose, is an acute, contagious virus disease. Trichomoniasis, Vibriosis, Listeriosis, and Foot and Mouth Disease are a few more diseases found in cattle, but there are many more.

Picture taken by myself


Why are you acting like that?

                Due to domestication, it is hard to describe the natural behavior and ecology of Bos taurus. They usually live in herds on average of about twenty-four to fifty-two cows in the wild. The benefits of these large herds are increased safety from predators and more chances for mating. Modern herds are a function of domestication and human manipulation. Herds are composed of females and the young. Males are separate from the herds and serve as a stud. This produces unnatural polygyny because the female have limited access to the males and only certain males are allowed to breed. This alters the natural breeding process which helps control reproduction and improves domestic stocks. Herds are structured by a dominance hierarchy. Each individual must yield to those cows above it. Dominant males maintain their status until they're defeated by younger males in challenges. Calves adopt their mother's status in hierarchy. Females are extremely protective of their young, and the group shares parental care. Cows communicate with chemical signals, touch, visual cues, and sound.


Got Milk?

                Milk is one of man's oldest and most essential foods. Dairy products have been around since the days of Ancient Egypt, when only royalty, priests and the wealthy could afford it. Originally cattle served as meat, milk and labor, but by the 5th century A.D., cows were prized for their milk in Europe. By the 14th century, cow's milk became more popular than sheep's milk. The first cows came to New England in the 17th century by way of the Plymouth Colony. Farms started off small, producing only enough milk for a family and a little extra to trade in town. A typical farm would have one or two cows to milk, plow fields and for transportation. In 1611, the first dairy cows were brought to Jamestown, Virginia. Today's dairy industry includes the farmers, who produce the milk; processors and manufacturers, who provide all the services needed to turn out a variety of wholesome, refreshing dairy foods; and the retailers, who bring these products directly to consumers (IDFA).

Picture taken by myself

Fun Facts:

    - A cow's tongue is the texture of sandpaper to pull grass and hay into the mouth.

      - Cows use their tails to swat flies.

      - Cows can't go down stairs because their knees don't bend right.

      - Cows' ears transfer heat.

      - Cows can smell odors up to five miles away.

      - The average cow produces 30 pounds of urine and 65 pounds of feces a day.

      - A cow's heart weighs approximately 5 pounds and pumps 400 pints of blood through the

        udder to produce one pint of milk.



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