The Science of Maryland Agriculture

Transcription

1 Edition 3 (2016) The Science of Maryland Agriculture GOAL STATEMENT: Students will differentiate between beef and dairy cattle (Bos tarus) and observe how each type evolved over time. OBJECTIVES: Students will compare and contrast breeds of dairy and beef cattle. Students will explain how breeds change and develop over time. REQUIRED MATERIALS: Per group of 4 students Teacher set of beef and dairy cattle breeds photographs Copies of Moo Who? worksheet (1 per student) Set of small beef and dairy cattle breeds photographs (1 set per small group) AMOUNT OF TIME TO ALLOW: 50 minutes. Extension activities may take additional time.

2 Cattle are one of the earliest species of animals to be domesticated, dating back almost 8,000 years. They have always been valued as a multi-use species serving as a source of meat, milk, labor, and transportation. Cattle were brought to what is now the United States in 1634 as some of the first animals in the Jamestown settlement. Through the years, selection has created two main categories of use for cattle dairy and beef. Even though dairy and beef cattle have been selected for differing purposes, they still share similarities and common ancestors. Whether they are dairy or beef, all cattle have 30 pairs of chromosomes, 32 teeth, and no upper front teeth. They typically have one calf a year, and females are pregnant for 9 months, just like humans. All cattle have similar digestive, skeletal, reproductive, and other body systems. All cattle are ruminants, meaning that they have four-compartment stomachs and are herbivores that eat and digest mainly forages (i.e. grasses and legumes). Today s cattle produce more milk and meat than their ancestors because of hundreds of years of selection for greater efficiency and growth. There are some breeds still considered to be dual-purpose (meaning for meat and milk), but most are now either beef or dairy cattle. Both dairy and beef cows begin to produce milk after they have their first calf, but dairy cows generally produce a substantially larger amount. On the other hand, dairy animals can be used for meat, but they do not produce as much as beef cattle. Terms that are important to know when referring to cattle (Bos tarus) are below. Ask each student what each term means and then explain further. Heifer a female that hasn t had her first calf Cow a female that has calved at least one time Bull a male capable of reproducing Steer a male raised for meat and unable to reproduce (castrated) Beef Cattle cattle raised primarily for meat production Dairy Cattle cattle raised primarily for milk production Dual Purpose animals used for two purposes (i.e. meat and milk) Udder an organ containing the glands used to produce milk found between the hind legs of a cow 10 minutes Ask students what food products we get from cattle. On the board, chart paper, or projector, sort these products into either beef or dairy (i.e. milk, cheese, yogurt and ice cream are dairy; roasts, steaks, hamburgers are beef). After you have a list of each category, ask students to explain the difference between beef and dairy cattle. Give the class some background information on beef and dairy cattle. Dairy animals provide milk, while beef cattle are raised primarily for meat production. Dual purpose breeds, which are used for both beef and dairy, also exist, especially in China, India, and other developing countries.

3 20 minutes Directions: 1. Divide students into groups of 2, 3, or Pass out the student handout to accompany the activity (1 handout per student). 3. Pass out sets of cattle pictures to students (1 set per group). Each set should contain pictures of 7 dairy breeds and 7 beef breeds. 4. Based on the appearance of the animals in the photos, ask the students to discuss, sort and chart the pictures of cattle into either dairy, beef, or dual-purpose breeds. 5. Have the students individually complete the rest of the handout and answer the questions based on their discussion and observations. 20 minutes Use the questions to guide a class discussion of why they think that an animal is in a certain category. Review each picture and tell the students the name and information provided about each breed. Reinforce that dairy animals have larger mammary systems/udders used to produce milk while beef breeds are more muscular to produce more meat. Dual purpose breeds have a combination of both. Show students the picture of the Milking Shorthorn and the Beef Shorthorn and describe that this is one breed that over time and selection has developed into distinct beef and dairy breeds but are still considered dual purpose. Have each student pick and research a specific dairy or beef cattle breed and provide a report. Information reported could include: how long the breed has been in the United States, the history of the breed, breed characteristics, etc. If you have internet access, you can visit the Virginia Cooperative Extension 4-H Virtual Farm and learn more about the dairy and beef industries. Have a local cattle professional come speak to your class about what his/her job entails or watch online videos pertaining to the cattle industry. For a more in-depth extension, have the students complete Undressing the Mystery of Meat lesson or Milk In Motion: A Dynamic Dairy Experiment lesson included with the AGsploration materials.

4 Student understanding can be evaluated through class discussion or assessment of completed activity data sheets. The following questions may also be used to evaluate student learning. 1. What criteria did you use to sort the cattle into dairy and beef groups? 2. Name two similarities and two differences between beef and dairy cattle. 3. Define a dual purpose breed. What is it used for? Dairy or Beef Farmer This person provides daily care for the cattle including feeding and watering, breeding, keeping health records, and ensuring the animals are healthy. Large Animal Veterinarian This person provides medical care for cattle and other large animals. He or she administers vaccines, assists with the birthing process, performs diagnostic tests on sick animals, and provides care for sick and injured animals. Milk or Meat Inspector This is a person who tests meat and milk products and inspects farms and facilities where these foods are produced and processed. This job is important in ensuring meat and milk products meet safe food standards. Cattle Nutritionist This person develops balanced diets for cattle so they receive proper nutrition and are able to reach maximum production. Artificial Insemination (A.I.) Technician This is a person who performs artificial insemination of cattle, or the breeding of female animals using fresh or frozen sperm that has been collected from a bull. Dairy Resource Handbook. The Ohio State University Extension, Beef Resource Handbook. The Ohio State University Extension, 2001.

5 Beef Breeds Teacher Key Angus This breed is all black with no horns and originated from Scotland. They are the most numerous beef cattle breed in the United States. They are known for their carcass quality (meat production) and mothering characteristics. Charolais This breed is all white and comes from France. It is known for fast growth and heavy, lean muscle. Hereford The breed is from England and the cattle are identified by their red bodies and white faces. Some have horns and others don t. These docile cattle are known for being some of the best animals at converting grass into muscle. Limousin This breed is from France and is traditionally solid in color ranging from golden to red. They are known for heavy muscle and lean meat. Shorthorn This breed originated in England and can be red, white, or speckled (roan). They are related to the Milking Shorthorn and are a more maternal breed. Simmental This breed is from Switzerland, and the cattle are traditionally red to dark red with white spots on their bodies. They are heavy milk producers and fast growers. Brahman These cattle were developed for meat production in Texas from cattle that originated in India. They are light grey to black and are known for their humps, extra skin, and long ears. This extra skin provides heat resistance and insect tolerance. Dairy Breeds Ayrshire This breed originated in Scotland, and the cattle are red and white. They are known for being hardy, good grazers with superior udder quality. Brown Swiss These cows originated in Switzerland and are known as the Big Brown Cows for their grayishbrown color. They are known for their size, strength, and excellent durability. Guernsey This breed is from the Isle of Guernsey, a small island off the coast of France. They are fawn color with white markings, and their skin and milk is yellowish. Black and White or Red and White Holstein This breed originated in Holland and can be either black and white or red and white. They are the most numerous breed of dairy cattle in the United States making up about 90% of U.S. dairy animals. They also produce the largest quantity of milk per cow of all dairy breeds. Jersey This breed originated in the Isle of Jersey off the coast of France. They are fawn color with black points, and the tongue and end of its tail are typically black. They produce the largest percentages of fat and protein in their milk. Milking Shorthorn This breed originated in England alongside the beef Shorthorn. They are red, white, or speckled (roan). They are known for their versatility. Dual Purpose Dual-purpose breeds provide both meat and milk; therefore, all cattle breeds can be considered dual purpose. The most common dual-purpose breed is the Shorthorn. The breed split into two specific lines over time due to genetic selection. The beef Shorthorn is better at producing quality meat, while the Milking Shorthorn is selected for it milking ability. Besides the Shorthorn breed, other breeds commonly considered dual purpose are Friesian, Devons and Red Polls. The Science of Maryland Agriculture because of race, age, sex, color, sexual orientation, physical or mental disability, religion, ancestry,

6 Name: Date: Period: 1. Organize the picture cards into the categories Beef, Dairy, or Dual Purpose. Record the results in the table: Beef Dairy Dual Purpose 2. What characteristics do the breeds that you grouped into the dairy category share? 3. What characteristics do the breeds that you grouped into the beef category share? 4. If you put any breeds in the dual purpose category, why do you think they belong there? 5. What are the differences between the breeds in the dairy and beef groups? The Science of Maryland Agriculture because of race, age, sex, color, sexual orientation, physical or mental disability, religion, ancestry,