Selective breeding is another practice to improve domesticated animals and plants. We select for breeding those individuals who have characteristics of our choice. We keep on breeding and selecting individual’s generation after generation till either we are satisfied with the product or no further improvement can be done.
Starting from a lean cow with very little milk, selective breeding was done in two directions (i) most milk (ii) most meat; one group of cattle breeders ended with large size modern beef cow with meat enough for lots of kebabs, steaks and roasts, the other group ended with modern dairy cow with lots of milk.
Hybridization and selective breeding have indeed produced a large number of improved varieties of animals and plants like Neeli-Ravi Buffalo, jersey – sahiwal cow, Dhani Ox, kajli sheep, Bital goat, teddy goat, Rahu – Thaila carp, broiler and Layer chicken, maxipak wheat and super kernel Basmati rice but it is a very slow process. It takes months and even years to raise a few generations of animals and plants (17.41, 17.42).
Genetic engineering has no match. It is a jet – speed process, because it depends on generations of bacteria that take just a few minutes or hours. Moreover the diverse applications of genetic engineering like cloning, gene therapy, finger printing, and gene libraries have absolutely no comparison. Selective breeding is out of fashion, genetic engineering is the most modern.
Fig 17.41:-Neeli is the famous breed of buffalo selected for centuries in the areas Punjab where river Sutlej flows. Ravi is the best breed of Ravi areas of Punjab. Their natural hybridization in areas of the common belt of the two rivers like Okara has resulted into famous crossbreed Neeli-Ravi.
Fig 17.42:-Rahu and Thaila are the two major carps of our rivers famous for their delicious white meat. Rahu – Thaila hybrid combines the superior taste of Rahu with larger size and faster growth rate of Thaila.