19 Sheep Breeding
19.1 Overview
This chapter provides an overview of sheep breeding with emphasis on wool, meat, and dual-purpose breeds.
19.2 Learning Objectives
By the end of this chapter, you should be able to:
- Describe breed types and their distinct breeding objectives
- Identify key traits and genetic parameters in sheep
- Explain the role of terminal sire crossbreeding in lamb production
- Understand genetic evaluation systems (LAMBPLAN, NSIP)
- Recognize challenges unique to sheep breeding
19.3 Global Sheep Industry
Chapter Status
This chapter is currently under development.
19.4 Breed Types and Objectives
- Wool breeds: Merino (fine wool production)
- Meat breeds: Suffolk, Hampshire, Dorset (terminal sires)
- Dual-purpose breeds: Polypay, Columbia, Targhee
- Hair sheep: Katahdin, Dorper
19.5 Key Traits and Heritabilities
19.5.1 Growth Traits
- Birth weight: h² = 0.25-0.45
- Weaning weight: h² = 0.25-0.45
19.5.2 Reproduction
- Litter size: h² = 0.10-0.15
19.5.3 Wool Traits
- Fleece weight: h² = 0.30-0.60
- Fiber diameter: h² = 0.30-0.60
19.6 Genetic Evaluation
- LAMBPLAN (Australia)
- NSIP (US)
19.7 Crossbreeding Systems
Terminal sire × maternal breed ewes
19.8 Summary
Sheep breeding objectives vary widely (wool, meat, dual-purpose). Terminal sire crossbreeding is widely used in meat production.