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Enhancement of Food Production — BIOLOGY STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYEnhancement of Food Production5 Marks
Question
Explain concept of outbreeding and its types.
✓

Answer

(1) Outbreeding involves breeding of two unrelated animals.
(2) It is of three types, viz. outcrossing, cross-breeding and interspecific hybridization.(3) Outcrossing:
  • Outcrossing involves mating of animals of same breed, which do not have a common ancestors on either side of mating partners up to 4 to 6 generations.
  • The progeny obtained from such mating is called an outcross.
  • Outcrossing is done to overcome inbreeding depression.
(4) Crossbreeding:
  • In crossbreeding superior males of one breed are mated with superior females of another breed.
  • New animal breeds of desirable characters are developed by this method.
  • Example : Hisardale breed of sheep is developed in Punjab by crossing Bikaneri ewes and Marino rams.
(5) Interspecific hybridization:
  • It involves breeding of animals of two different but related species.
  • It is used to produce animals with desirable characters from both the parents.
  • e.g. Mule is a breed obtained from horse and donkey.
  • It may not be always successful.

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