Principles of Genetics and Breeding

12.1.3 Line Breeding

• Line breeding occurs when an outstanding individuals (usually male) is brought back into the line to mate with a descendant.
• This is done because the animals is so outstanding that his contribution to each descendant is increased in the gene pool.
• There are two types of line breeding. A male with good quality in his trait has great importance as a family founder in development of a new population. To develop an inbred population, conscious and strict selection should be done to remove or cull the genetically declined individuals.
• In mild line breeding, individual A contributed 53.12% of individuals K’s genes.
• In intense line breeding, individual A contributed 93.75% of individual G’s genes (Fig.2).
• Finally,inbreeding is often combined with crossbreeding to increase hybrid vigour.