*3.2.5 Cross breeding*

Cross breeding is mating of two individuals from different distinct breeds. In recent years, crossbreeding has been used for development of new breeds or synthetics strain. For example: Santa Gertrudis, Jamaica Hope, Norwegian Red and White, Australian Milking Zebu, Hissardale, Karan Swiss, Sunandini, Taylor breed

#### **Figure 6.**

*Representative cross for genetic improvement of non-descript zebu cattle by crossbreeding unit [5].*

### *Basic Animal Breeding Methods DOI: http://dx.doi.org/10.5772/intechopen.104136*

etc. [4, 5]. The representative diagram for genetic improvement of non-descript zebu cattle by crossbreeding is shown in **Figure 6**.

Crosses of animals from different breeds result in offspring whose level of production is above that of the average of the parents. The increased production may be due to increased fertility, increased pre and post-natal viability, faster and more efficient growth, improved mothering ability, etc. The increased level of performance as compared to the average of the parents is known as heterosis or hybrid vigor. Heterosis is due to non-additive gene action. The breeds or lines with good nicking ability or combining ability are crossed to exploit heterosis.
