Publications by authors named "Jaap R"
Gametic products transmitted by chickens heterozygous for chromosomal rearrangements.
Cytogenet Cell Genet
April 1979
Chromosomal analysis was made from 3744 chick embryos derived from reciprocal matings between parents, one of which was heterozygous for a pericentric inversion, a centric fission, or one of three translocations. The objectives were to determine the types and frequencies of genetically balanced and unbalanced gametes transmitted to early embryos by rearrangement heterozygotes and to ascertain if some gametic types were preferentially produced or utilized. The array of embryos obtained from the heterozygous sires did not deviate significantly from the expected, except in the case of the centric fission group.
View Article and Find Full Text PDFThe parental source of heteroploidy in chick embryos determined with chromosomally marked gametes.
J Reprod Fertil
January 1978
Article Synopsis
- Males with chromosomal translocations were bred with normal females, resulting in embryos that were subjected to cytogenetic analysis after 16-18 hours of incubation.
- Out of 62 embryos analyzed, 54 (7.8%) exhibited abnormal chromosomal configurations, indicating various levels of ploidy including haploid, diploid, triploid, and tetraploid forms.
- The findings suggest that the diverse embryonic ploidy levels resulted from issues in meiotic division and fertilization processes, with specific markers indicating different genetic origins among the embryos.
In order to produce chicks heterozygous for structural aberrations of chromosomes, 67 hens were inseminated with semen that had been exposed to 1200 R of X-rays. A sample of 204 chicks was hatched and survived. Among these, 18 (8.
View Article and Find Full Text PDFArticle Synopsis
- Measurements showed the Z-chromosome is metacentric, with 46% of one arm translocated to a microchromosome due to semen irradiation.
- Semen from a Z-micro female inseminated 98 dwarf broiler-type females, resulting in offspring with distinct genetic variations in body weight and egg production.
- Heterozygous males for Z-micro were significantly heavier than their normal counterparts, while Z-micro females exhibited reduced weight and delayed egg production.
A normal-bodied broiler population and one dwarfed by the dw sex-linked gene were each sub-divided into two lines. AGB (normal) and D2B (dwarf) were selected only for superior body weight at eight weeks of age. AGE (normal) and D2E (dwarf) were sublines in which prospective dams were selected for large egg weight while prospective sires were selected for eight-week body weight.
View Article and Find Full Text PDFSmall 1.1 kg. egg-type pullets having the sex-linked dw dwarfing gene were more resistant to a force molting program started at 11 months of age than were their 1.
View Article and Find Full Text PDFPreparations for chromosomal analysis were made from 2107 chick embryos at 16 hours of incubation. The embryos resulted from intraline and reciprocal interline matings of two genetically different stocks (AG and D6). The two stocks had been previously characterized as producers of high (AG) and low (D6) frequencies of chromosomally aberrant embryos.
View Article and Find Full Text PDFThe lipogenic activity of propylthiouracil, triphenylchloroethylene and hexestrol in chickens.
J Clin Endocrinol Metab
July 1948