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Details for article 15 of 15 found articles
| Title: |
Twelve year summary of selection for parthenogenesis in Beltsville Small White turkeys |
| Author: |
Olsen, M. W. |
| Appeared in: |
British poultry science |
| Paging: | Volume 6 (1965) nr. 1 pages 1-6 |
| Year: |
1965-01 |
| Contents: |
Parthenogenetic development was found in 16.7 per cent of 934 Beltsville Small White turkey eggs in 1952. This development, occurring during incubation, was chiefly of an unorganised type, blood or embryos being encountered only on rare occasions. In 1954, a selective breeding programme was initiated which was designed to intensify this trait. This has resulted in marked yearly increases in the average level of parthenogenetic development. Since 1952 there has been a three-fold increase in the overall incidence of parthenogenesis and presently 45 per cent of all unfertilised eggs incubated can be expected to undergo development to some extent. The most marked increases have come in the number of eggs giving rise to well-formed embryos. At the present time from 12-13 Per cent of all eggs can be expected to contain embryos, representing a 65-fold increase over the level found in eggs of the original stock. Corresponding increases have likewise occurred in embryo viability. The few embryos encountered before 1954 rarely attained the size of a normal 5-6 day embryo. During the last three years approximately 34 per cent of all parthenogenetic embryos lived for 21 days or longer and 7 of every 100 of them emerged or were helped from the shell on the 29th or 30th day of incubation. One hundred and six parthenogenetic poults were hatched from 10,060 eggs in 1961, 94 from 8519 eggs in 1962, and 23 from 5906 eggs in 1963. About 25 per cent of the parthenogenetic poults which have hatched survived to maturity. Some of these have produced semen containing viable spermatozoa. More than 25 parthenogenetic males thus far have demonstrated their ability to sire offspring. |
| Publisher: |
Taylor & Francis |
| Source file: |
Elektronische Wetenschappelijke Tijdschriften |
Details for article 15 of 15 found articles
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