| Project/Area Number |
12660260
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Applied animal science
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| Research Institution | Kyoto Sangyou University |
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Principal Investigator |
NOMURA Tetsuro Kyoto Sangyou University, Faculty of Engineering, Professor, 工学部, 教授 (50189437)
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| Project Period (FY) |
2000 – 2001
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| Project Status |
Completed (Fiscal Year 2001)
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| Budget Amount *help |
¥1,500,000 (Direct Cost: ¥1,500,000)
Fiscal Year 2001: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 2000: ¥1,000,000 (Direct Cost: ¥1,000,000)
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| Keywords | Cloning / Breeding structure / Statistical genetics / Beef cattle / Genetic diversity / Effective population size / Inbreeding / クローン / 家畜育種 / 遺伝的多様体 / 遺伝的改良 |
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| Research Abstract |
The efficiencies of the use of cloning technique were evaluated under three typical situations of beef cattle breeding, by means of statistical genetics methods.
1. Use of clones as commercial stock
The intuitive merit of the use of clones as commercial stock is the increase in uniformity of final products. This expectation was evaluated in terms of the coefficient of correlation and the standard error of difference between clones. It was shown that clones would be somewhat more uniform than other pairs of relatives, but would not be as uniform as most people would expect.
2. Clone testing
The efficiency of clone testing as an alternative to the conventional progeny testing was evaluated in terms of the accuracy of selection. It was found that there are situations under which the conventional progeny testing is preferable to the clone testing, depending on the amount of dominance variation and the number of tested animals.
3. Use of cloned sires
(1) Probability of finding a "super" sire
A "super" sire is defined as a bull who has a prominent performance enough to justify to make his clones. Using a deterministic model, the probability that we can find a "super" sire was calculated. The results showed that in a population with a moderate genetic gain, the probability would be quite low.
(2) Effect of the use of cloned sires on genetic diversity
Applying a stochastic simulation technique to pedigree records of Japanese Black cattle, the effect of the use of cloned sires on genetic diversity was examined. In a population in which the donor sire had been intensively used, the use of his clones would lead to a drastic reduction of genetic diversity.
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