Synaptonemal complex analysis of hybrid cattle. I. Pachytene substaging and the normal full bloods

Genome ◽  
1989 ◽  
Vol 32 (5) ◽  
pp. 856-864 ◽  
Author(s):  
A. E. Dollin ◽  
J. D. Murray ◽  
C. B. Gillies
Keyword(s):  
Electron Microscopy ◽  
Synaptonemal Complex ◽  
Chromosome Pairing ◽  
Complex Analysis ◽  
Bos Taurus ◽  
Meiotic Chromosome ◽  
Early Pachytene ◽  
Meiotic Chromosome Pairing ◽  
Synaptonemal Complex Analysis

Meiotic chromosome pairing abnormalities in full-blood and hybrid Bos taurus and B. indicus cattle have been surveyed by electron microscopy of pachytene synaptonemal complex spreads. In this paper, the full-blood spreads are described in detail, including the use of XY and nucleolar morphology and other measured parameters for pachytene substaging. Pairing abnormalities were observed in up to 9% of the full-blood spreads. Most of these pairing abnormalities (83%) occurred in early-pachytene spreads, suggesting that the mechanism of synaptic adjustment may operate in cattle.Key words: synaptonemal complex, cattle, pachytene substages.

Synaptonemal complex analysis of hybrid cattle. III. Meiotic pairing mechanisms in F1 Brahman × Hereford hybrids

Genome ◽  
1991 ◽  
Vol 34 (2) ◽  
pp. 228-235 ◽  
Author(s):  
A. E. Dollin ◽  
J. D. Murray ◽  
C. B. Gillies
Keyword(s):  
Synaptonemal Complex ◽  
Chromosome Pairing ◽  
Complex Analysis ◽  
Bos Taurus ◽  
Bos Indicus ◽  
Meiotic Pairing ◽  
Homoeologous Chromosome ◽  
Homoeologous Chromosome Pairing ◽  
Synaptonemal Complex Analysis ◽  
Complex Hybrid

The mechanisms of homoeologous chromosome pairing were studied in synaptonemal complex (SC) spreads of F1 Brahman (Bos indicus) × Hereford (Bos taurus) cattle. The most common SC abnormalities were bivalents with partial pairing failure and interlocks. While C-band polymorphisms could underlie most of the SC abnormalities observed in the full-blood cattle, other causes seem also to be contributing in the hybrids. The pattern of the abnormalities indicates that genie differences between the species were probably involved. Pachytene substaging data suggest that in some spreads, early pachytene bivalents with partial pairing failure may achieve complete synapsis or may be converted to interlocks by late pachytene.Key words: synaptonemal complex, hybrid cattle, interlocks.

Synaptonemal complex analysis of hybrid cattle. II. Bos indicus × Bos taurus F1 and backcross hybrids

Genome ◽  
1991 ◽  
Vol 34 (2) ◽  
pp. 220-227 ◽  
Author(s):  
A. E. Dollin ◽  
J. D. Murray ◽  
C. B. Gillies
Keyword(s):  
Synaptonemal Complex ◽  
Complex Analysis ◽  
Bos Taurus ◽  
Meiotic Chromosome ◽  
Bos Indicus ◽  
Backcross Hybrid ◽  
Synaptonemal Complex Analysis ◽  
Backcross Hybrids ◽  
Fertility Problems ◽  
And Inversion

The levels of meiotic chromosome pairing abnormalities observed in six Australian F, Bos indicus x Bos taurus cattle crosses (mean = 23%) were significantly higher than those of the full-blood breeds (9%). The abnormal configurations in the F[hybrids included partial pairing failure, multivalents, interlocks, and inversion pairing. Abnormal configurations were also present, but at lower frequency, in backcross hybrid bulls. The main types of abnormal configurations and the levels of XY-autosomal associations and autosomal asynapsis observed were unlikely to cause significant fertility problems in the hybrids.Key words: synaptonemal complex, hybrid cattle, meiosis.

Synaptonemal complex analysis in primary spermatocytes of cattle x zebu hybrids (Bos taurus × Bos indicus)

1990 ◽  
Vol 107 (1-6) ◽  
pp. 229-238 ◽  
Author(s):  
M. Switonski ◽  
H. A. Ansari ◽  
A. Matthew ◽  
H. R. Jung ◽  
G. Stranzinger
Keyword(s):  
Synaptonemal Complex ◽  
Complex Analysis ◽  
Bos Taurus ◽  
Bos Indicus ◽  
Synaptonemal Complex Analysis

scholarly journals Synaptonemal complex analysis of Nellore and Gyr breeds of Bos taurus indicus

Caryologia ◽  
2000 ◽  
Vol 53 (2) ◽  
pp. 141-146 ◽  
Author(s):  
Marcia Denise Paixao Scavone ◽  
Claudio Oliveira ◽  
Luzia Aparecida Trinca ◽  
Fausto Foresti
Keyword(s):  
Synaptonemal Complex ◽  
Complex Analysis ◽  
Bos Taurus ◽  
Bos Taurus Indicus ◽  
Synaptonemal Complex Analysis

Synaptonemal complex analysis of domestic sheep (Ovis aries) with Robertsonian translocations. I. Pachytene karyotype substaging of normal sheep.

Genome ◽  
1994 ◽  
Vol 37 (4) ◽  
pp. 672-678 ◽  
Author(s):  
K. Dai ◽  
A. E. Dollin ◽  
C. B. Gillies
Keyword(s):  
Synaptonemal Complex ◽  
Complex Analysis ◽  
Meiotic Chromosome ◽  
Ovis Aries ◽  
Domestic Sheep ◽  
Autosomal Bivalents ◽  
Robertsonian Translocations ◽  
Synaptonemal Complex Analysis ◽  
Pachytene Karyotype ◽  
Pairing Behaviour

Meiotic chromosome pairing behaviour in three normal sheep was surveyed by synaptonemal complex (SC) analysis at the electron microscope level. The SC karyotype of normal rams is composed of a sex pair, three metacentric or submetacentric pairs, and 23 acrocentric autosomal bivalents, with the total autosomal SC length ranging from 309 to 315 μm. Five nucleoli are terminally located on the three metacentric, and one large and one small acrocentric autosomal bivalents. XY morphology was used to divide pachytene into five substages. Although pairing abnormalities (mostly SC interactions) were recorded in an average of 16% of the spermatocytes, bivalent–XY association occurred in only 4.7% of the cells.Key words: sheep, synaptonemal complex, XY pair, pachytene substaging.

Quadrivalent formation in a tetraploid chicken oocyte

Genome ◽  
1988 ◽  
Vol 30 (6) ◽  
pp. 900-902 ◽  
Author(s):  
A. J. Solari ◽  
N. S. Fechheimer
Keyword(s):  
Electron Microscopy ◽  
Synaptonemal Complex ◽  
Complex Analysis ◽  
W Chromosome ◽  
Autosomal Bivalents ◽  
Initiation Point ◽  
Recombination Nodule ◽  
Synaptonemal Complex Analysis ◽  
Threshold Length ◽  
Pairing Initiation

Synaptonemal complex analysis of an exceptional tetraploid oocyte from a diploid chicken heterozygous for the MN t (Z;1) rearrangement was performed by electron microscopy of a spread preparation. Ten separate quadrivalents (26% of the chromosomal axes) were analyzed, as well as 50 autosomal bivalents. All the axes less than 2.5 μm in length formed bivalents (38) only, while axes in the 2.5–4.2 μm range formed 5 quadrivalents and 12 bivalents. The longer, separate axes formed quadrivalents only. Partner switches in excess of one were documented. The two identical W chromosomes paired only at the ends of their short arms. Quadrivalent formation may require a threshold length (2.5 μm), at least in this species. The tip of the short arm of the W chromosome may be a pairing initiation point, and it corresponds to the region associated with a localized recombination nodule previously described in diploid oocytes.Key words: quadrivalent, tetraploid, synaptonemal complex, chicken oocyte.

Sign in / Sign up

Export Citation Format

Share Document