This document is a teacher's guide for a unit in the college animal science curriculum. It is intended to be used for 20 hours of instruction for freshmen as an introduction to animal science. It explores the livestock industry and builds a foundation for livestock selection. The unit's objectives are to help the student develop an understanding of the history, importance, and functions of the livestock industry, and the ability to identify animal parts, select livestock, and to identify breeds of livestock. The unit is divided into material for six jobs, as follows: (1) examining the history of the livestock industry; (2) recognizing the importance of the livestock industry; (3) understanding the functioning of the livestock industry; (4) identifying animal parts; (5) selecting livestock and giving reasons for the selection; and (6) identifying breeds of livestock. Each of the jobs includes objectives, guide questions, references, an approach to interest students, key facts about the content of the material, student learning activities, and transparency masters. A list of the names and addresses of breeding associations for beef, swine, sheep, dairy cattle, and horses is included as part of job six. (KC)