Which method is commonly used for improving cattle breeds and why?

Answer

N/a

Explanation

The milk production of cattle can be increased by the technique of selective breeding. This is done by cross breeding between a local breed (indigenous breed, e.g., Red Sindhi, Sahiwal) cow and an exotic (foreign breed, e.g., Brown Swiss) bull. The local cow is selected for the character of disease resistance. The exotic breed of bull is selected for the character of prolonged period of lactation and high yield of milk. The breeding may be done by natural methods or by artifical insemination (i.e., injecting the semen obtained from the desired bull into reproductive tract (vagina) of the cow during fertility period). The desired characters are thus obtained in the next generation.