The traditional Highland cow. Fresian cows have been bred to produce large volumes of milk. Aberdeen Angus cows have also been bred for their meat. A wide range of characteristics can be chosen for usefulness or appearance. Desired characteristics in plants:. Desired characteristics in animals:. Selective breeding leads to future generations of selectively bred plants and animals, all sharing very similar alleles which will reduce variation. Genes and their different alleles within a population are known as its gene pool.
Inbreeding can lead to a reduced range of alleles in the gene pool, making it more difficult to produce new varieties in the future. It is interesting to realise that these herdbooks were established without any knowledge about genetics. Breeders had a feeling about inheritance and that was sufficient to invent this selective breeding. Quick Search. Hit enter to search. Animal breeding. Expand all Collapse all. A t tachments 0 Page History People who can view.
Skip to end of banner. Jira links. The start in the th century Until roughly the 's animal breeding, as in selective breeding, did not really exist.
Establishment of herdbooks With time the number of people increased who were using the selective breeding approach introduced by Bakewell. Creation of breeds With the establishments of herdbooks, breeds were formed. We do not know as much of his life as would be the case had his contemporaries realized at the time of the magnitude of his discoveries, or appreciated the far-reaching influence of his work. We know this, however, that flying squarely in the face of all preconceived notions governing the production of farm animals, he was the first of the world's great animals breeders, of which there is record, to demonstrate the power of the principle of the concentration of blood elements as the readiest and most effective method of establishing and fixing desired characteristics.
The scene of his labors was at Dishley, Leicestershire, England, and his great success was made with the long-wooled Leicester sheep and Longhorn cattle, the latter then a widely distributed type in all the midland counties of Britain.
His work is said to have been conducted at first with more or less secrecy so far as the public was concerned. Aware of the general prejudice existing at the time against close breeding, he probably did not care to call down criticism while still experimenting. Some have intimated that in the case of his "improved Leicesters" he was actuated by a desire to conceal one of the real sources of the betterment attained.
One story ran to the effect that he had used in his earlier experiments an extraordinary black-face "tup," which no visitor was ever permitted to see, and the occasional appearance of blackish lambs among the descendants of the Dishley sheep long years later was cited as an illustration of the power of atavism or reversion to an original type even after the lapse of many generations.
Naturally, progress was more rapid with the Leicesters than the Longhorns, and it was not long before the flockmasters of the entire kingdom were taking notice of the marvels being wrought. One celebrated ram, Two Pounder , is said to have earned Guineas in a single season! The improvement of the Longhorns followed, and the Dishley "breed" became the prevailing popular type in all the neighboring districts.
He is said to have maintained somewhat of a "museum," or as Dixon calls it, a "business room," in which there were preserved both skeletons and "pickled carcasses" illustrating interesting results attained.
Among these later trophies of the Longhorns were some joints that were prized relics of Old Comley , that died at the good old age of 26, with fully four inches of outside fat upon his sirloin.
The herd was distinguished above all others for its depth of flesh, and Bakewell did not for a moment doubt that he had evolved a type which would "represent the roast beef of old England forever and aye. King George III became interested, and honored the wizard with a royal inquiry as to his "new discovery in stock breeding. To understand the full import of Bakewell's work, it is necessary to know that his great successes antedated the creation of all the leading breeds of the present day.
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