Unit Animal Science

Animal Genetics and Biotechnology Problem Area Animal Genetics and Biotechnology

Lesson Biotechnology

Student Learning Objectives 1. Identify the major areas of biotechnology in animal science. 2. Explain various molecular biotechnology methods. 3. Discuss applications of molecular biotechnology. 4. Discuss applications of organismic biotechnology.

Terms Animal biotechnology Biotechnology Embryo transfer Genetic engineering Gene transfer Microinjection Molecular biotechnology Organismic biotechnology Particle injection Plasmids Recombinant DNA Superovulation Transgene Transgenic animal

What are the major areas of biotechnology in animal science? Biotechnology is the management of biological systems for the benefit of people and their environment. It is also viewed as the application of science in food and fiber production. Biotechnology has been used for hundreds of years. Using yeast to make bread and bacteria to make cheese are everyday examples of biotechnology. Animal biotechnology is the application of biotechnology methods to improve animals. There are two major areas of bio-technology in animal science.

A. Molecular biotechnology—Molecular biotechnology is changing the structure and parts of cells to change the organism. It begins with the atom. Molecular biotechnology often changes the physical appearance of an organism. In some cases, undesirable traits may develop along with those that are desired. B. Organismic biotechnology—Organismic biotechnology deals with intact or complete organisms. The genetic makeup of the organism is not artificially changed. This is the most widely used type of biotechnology.

What are some of the various molecular biotechnology methods? A. Genetic Engineering—Genetic Engineering is a form of biotechnology in which genetic information is changed to make a new product. Through this process, sections of the DNA strand are cut out and new sections are inserted. Gene transfer is the moving of a gene from one organism to another. Genetic engineering is a means of complementing traditional breeding programs.

B. Recombinant DNA—Recombinant DNA is gene slicing B. Recombinant DNA—Recombinant DNA is gene slicing. Genes are cut out of a DNA strand with a restriction enzyme that works like a scalpel. They are then inserted into circular DNA molecules in bacteria plasmids. Plasmids are circular pieces of DNA found outside the nucleus in bacteria. The plasmid is inserted into the cell that is to be altered. This allows the DNA of two different organisms to be combined. This is a very complicated and complex procedure. Most cells die in the process. Many surviving cells do not have the new DNA present in the nucleus.

C. Transgenic Animals—A transgenic animal is an animal that has incorporated a foreign gene into its cells. This animal can pass to its offspring this transgene, or altered gene. All of the cells within the transgenic animal contain this transgene. Some common transgenic methods are: 1. Microinjection—This is the most common method used. Injecting DNA into a cell using a fine diameter glass needle and a microscope constitutes microinjection. 2. Particle injection—Particle injection is using a microprojectile unit to shoot tiny particles coated with DNA into cells. Microprojectile units are sometimes called particle guns. Both methods have relatively low success rates.

What are some of the applications of molecular biotechnology? A. Human health—Animals are being used to study several different types of diseases found in humans. Insulin was once extracted from the pancreas of slaughtered cattle and hogs. This extraction process was very expensive. Sometime the insulin from the animals caused allergic reactions to the diabetics who used it. Through molecular biotechnology, insulin is now produced artificially in laboratories. This artificial insulin is of higher quality and less expensive to produce. This is just one example of a product being developed through biotechnology that will benefit human health. Many more are on the horizon.

B. Food production—Increasing the levels of beta casein in milk decreases the time required for rennet coagulation and whey expulsion in making cheese. This lowers total processing time and cost. Also through biotechnology, the fat content in milk can be reduced to make fat-free cheese and ice cream. If a substance known as kappa casein is increased 5 percent in milk, it makes it more stable and easier to ship. These are only a few examples of food products that have been developed through biotechnology. Soon, many new foods will be introduced on the market that are high in quality. C. Livestock production—The use of biotechnology has increased growth rate, efficiency, and disease resistance in livestock. This has made livestock production cost decline and aids in the supply of a low cost food supply.

What are some applications of organismic biotechnology? A. Greater fertility—Increasing the reproductive capacity of top animals is important to producers. Two methods to increase the reproductive capacity of animals are: 1. Superovulation—Superovulation is getting a female to release more than the usual number of eggs during a single estrous cycle. Hormones are injected to assure more eggs. 2. Embryo transfer—Embryo transfer is taking an embryo from its mother and implanting it in another female. The embryo completes development in the recipient.

B. Increased production—Three methods used to increase production are: 1. Milk hormones—Injections of milk hormones cause the cow’s mammary system to become more productive. The most common milk hormone is bovine somatotropin (bST). Since bST is a naturally occurring hormone, it has been widely accepted in the dairy industry. 2. Meat hormones—Injections of meat hormones causes the animal to produce more muscle cells resulting in larger and leaner cuts of valuable meat. 3. Growth implants—Growth implants are small pellets placed under the skin. They promote growth by making the animal more feed efficient.

C. Enhancing animal nutrition—The greatest results of biotechnology have been seen in animal nutrition. Some of the enhancements are: 1. Digestibility testing—Tests are made by getting samples from the digestive systems of animals after they have eaten. This information is used to improve feed use and animal growth. 2. Controlled feeding—Computer chips can be put in a monitor around the animal’s neck, ear tag or under the skin. A computerized feeding station will read the chip and regulate the amount of feed the animal receives. Daily feed intake by the animal is used to aid in the detection of health problems.

Review/Summary What are the major areas of biotechnology in animal science? What are some of the various molecular biotechnology methods? What are some of the applications of molecular biotechnology? What are some applications of organismic biotechnology?