Class 12th Biology 2018 Set1 Delhi Board Paper Solution
Question 18
Explain out-breeding, out crossing and cross-breeding practices in animal husbandry.
Answer
Out-breeding: It refer to the breeding of unrelated animals of same breed but do not have common ancestors.
Cross-breeding: It is an out-breeding technique in which the mating of superior male of one breed with superior female of another breed. Eg. Hisardale was obtained in Punjab by crossing Marino rams and Bikaneri ewes.
Out-crossing: It is a practice if mating animals of same breed that donot have any common ancestor for 4 to 6 generation.
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