Synaptonemal complex analysis of domestic sheep (Ovis aries) with Robertsonian translocations. II. Trivalent and pairing abnormalities in Massey I and Massey II heterozygotes

Genome ◽  
1994 ◽  
Vol 37 (4) ◽  
pp. 679-689 ◽  
Author(s):  
K. Dai ◽  
C. B. Gillies ◽  
A. E. Dollin
Keyword(s):  
Complex Analysis ◽  
Ovis Aries ◽  
Domestic Sheep ◽  
Robertsonian Translocations ◽  
Xy Bivalent ◽  
Synaptonemal Complex Analysis ◽  
Unpaired Chromosome ◽  
Pachytene Spermatocytes ◽  
Small Testis ◽  
Trisomic Cell

Zygotene and pachytene spermatocytes from Massey I (t1 5;26) and Massey II (t2 8;11) translocation heterozygotes each contained one trivalent, often delayed in pairing, while cells from double Massey translocation heterozygotes had two such trivalents. As meiosis progressed, trivalents became fully paired, with acrocentric axes in a cis configuration. Abnormal pairing configurations often resulted from interactions between unpaired chromosome axes or segments. However, when two Massey trivalents were present in the same nucleus, there was no pairing interaction between them. In different Massey translocation heterozygotes, trivalent-involved pairing abnormalities occurred in 14–28% of cells, with XY–trivalent and XY–bivalent–trivalent associations being as high as 7.1–23.1%. In spermatocytes from single and double Massey translocation heterozygotes with normal-sized testes, the total SC abnormality frequency was 34.4% for the t1 heterozygotes, 27.1% for the t2 heterozygotes, and 21.4% for the double heterozygote. One Massey II heterozygote with one normal and one small testis had significantly higher SC abnormality frequency (54%) than normal rams. A trisomic cell was recorded in one ram and two hyperdiploid cells in another ram, but these were unrelated to the translocations. It is suggested that resolution of pairing abnormalities by synaptic adjustment is important in reducing the effects on fertility of the translocations.Key words: sheep, Robertsonian translocation, trivalent, abnormal pairing configuration.

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.

Synaptonemal complex analysis of domestic sheep (Ovis aries) with Robertsonian translocations. III. Deficient pairing and NOR role in Massey III heterozygotes

Genome ◽  
1994 ◽  
Vol 37 (5) ◽  
pp. 802-808 ◽  
Author(s):  
K. Dai ◽  
C. B. Gillies ◽  
A. E. Dollin
Keyword(s):  
Synaptonemal Complex ◽  
Complex Analysis ◽  
Chromosome Rearrangement ◽  
Nucleolar Organizer ◽  
Ovis Aries ◽  
Domestic Sheep ◽  
Nucleolar Organizer Regions ◽  
Robertsonian Translocations ◽  
Synaptonemal Complex Analysis ◽  
Pairing Behaviour

Spermatocytes from rams heterozygous for Massey translocation III (t37;25) contained one trivalent and those from the rams heterozygous for both Massey translocations I and III (t1t3) contained two trivalents. Where two trivalents and the XY pair are present in the same nucleus they may form a synaptonemal complex (SC), but no SC segment is found between the two trivalents. The frequency of pairing abnormality in four t3 rams and two t1t3 rams did not significantly differ from that in the normal sheep, but t3 trivalents with diverse abnormal configurations were recorded. A hypothesis was proposed that nucleolar organizer regions (NORs) or nucleoli could account for deficient pairing behaviour and hence chromosome rearrangement, because the NOR region on an NOR-bearing chromosome was usually delayed in pairing, and unpaired regions tended to associate with other unpaired axes or SCs.Key words: Bovidae, NOR, deficient pairing, chromosome rearrangement.

Synaptonemal Complex Analysis of Sex Chromosomes in Two Species of Sceloporus

Copeia ◽  
1990 ◽  
Vol 1990 (4) ◽  
pp. 1122 ◽  
Author(s):  
Kent M. Reed ◽  
Philip D. Sudman ◽  
Jack W. Sites ◽  
Ira F. Greenbaum
Keyword(s):  
Synaptonemal Complex ◽  
Sex Chromosomes ◽  
Complex Analysis ◽  
Synaptonemal Complex Analysis

​Re-sequencing of Whole Genome Jordanian Awassi Ewes using Hiseq Sequencing Technology: Major Step Towards Sheep Genomic Selection

2021 ◽  
Author(s):  
Hussein Migdadi ◽  
Nizar Haddad ◽  
Ruba AlOmari ◽  
Mohammad Brake ◽  
Mustafa AlShdaifat ◽  
...  
Keyword(s):  
Production Systems ◽  
Ovis Aries ◽  
Domestic Sheep ◽  
Major Step ◽  
Illumina Hiseq ◽  
Structure Variation ◽  
Awassi Sheep ◽  
Wide Range ◽  
Number Variation ◽  
Paired End Sequencing

Background: Jordanian Awassi sheep (Ovis aries) is the dominant fat tail sheep breed that appeals to customers because of its various production systems, including fiber, meat and milk. This report is the first whole ewe genome sequence (WGS) of O. aries submitted in the NCBI database from Jordan. Methods: 64 Paired-end sequencing libraries were constructed and subjected to Illumina Hiseq 2500 sequencing system. High-quality reads were aligned against the reference sheep genome and detecting comprehensive sources (SNPs, InDels, SV, CNVs) of genetic variations. We have deposited data sequences at the NCBI under SRA (sequence reads archives) under the accession numbers SRR11128863, PRJNA574879. Result: Genome resequencing of Jordanian Awassi ewe was carried out with approximately 93.88 Gb with a mapping rate and effective mapping depths were 99.28% and 36.32. Around 19 million SNPs, 3,6 million InDels, 35,180 Structure variation and 13,524 copy number variation among the Jordanian ewe genome were detected. This wide range of genetic variation provides a framework for further genetic studies that will help understand the molecular basis underlying phenotypic variation of economically important traits in sheep and improve intrinsic defects in domestic sheep breeds.

Field metabolic rate and water turnover of red kangaroos and sheep in an arid rangeland: an empirically derived dry-sheep-equivalent for kangaroos

2009 ◽  
Vol 57 (1) ◽  
pp. 23 ◽  
Author(s):  
A. J. Munn ◽  
T. J. Dawson ◽  
S. R. McLeod ◽  
D. B. Croft ◽  
M. B. Thompson ◽  
...  
Keyword(s):  
Metabolic Rate ◽  
Grazing Pressure ◽  
Ovis Aries ◽  
Domestic Sheep ◽  
Detailed Knowledge ◽  
Water Turnover ◽  
Field Metabolic Rate ◽  
Red Kangaroo ◽  
Resource Requirements ◽  
Comparative Measure

Sustainable management of pastures requires detailed knowledge of total grazing pressure, but this information is critically lacking in Australia’s rangelands where livestock co-occur with large herbivorous marsupials. We present the first comparative measure of the field metabolic rate (an index of food requirement) of Australia’s largest marsupial, the red kangaroo (Macropus rufus), with that of domestic sheep (Ovis aries; merino breed). We tested the assumption that the grazing pressure of red kangaroos is equivalent to 0.7 sheep, and show this to be a two-fold overestimation of their contribution to total grazing. Moreover, kangaroos had extraordinarily lower rates of water turnover, being only 13% that of sheep. Consequently, our data support arguments that the removal of kangaroos may not markedly improve rangeland capacity for domestic stock. Furthermore, given the low resource requirements of kangaroos, their use in consumptive and non-consumptive enterprises can provide additional benefits for Australia’s rangelands than may occur under traditional rangeland practices.

Synaptonemal complex analysis of X-7 translocations in male mice

Chromosoma ◽  
1982 ◽  
Vol 87 (2) ◽  
pp. 149-164 ◽  
Author(s):  
Terry Ashley ◽  
Liane B. Russell ◽  
N. L. A. Cacheiro
Keyword(s):  
Synaptonemal Complex ◽  
Complex Analysis ◽  
Male Mice ◽  
Synaptonemal Complex Analysis

Description of Diploplastron dehorityi sp. nov. (Entodiniomorphida, Ophryoscolecidae), a new rumen ciliate from Brazilian sheep (Ovis aries)

Zootaxa ◽  
2017 ◽  
Vol 4258 (6) ◽  
pp. 581 ◽  
Author(s):  
FRANCIANE CEDROLA ◽  
ROBERTO JÚNIO PEDROSO DIAS ◽  
ISABEL MARTINELE ◽  
MARTA D’AGOSTO
Keyword(s):  
New Species ◽  
Body Shape ◽  
The Body ◽  
Ovis Aries ◽  
Domestic Sheep ◽  
Diagnostic Features ◽  
Ciliate Community ◽  
The Right ◽  
A New Species

To date the genus Diploplastron comprised only one species of ophryoscolecid ciliate, Diploplastron affine, which is characterized by having two retractable ciliary zones in the anterior end of the body, two slender and juxtaposed skeletal plates on the right side, a rod shape macronucleus, and two contractile vacuoles. During study on the characterization of rumen ciliate community composition in Brazilian domestic sheep, we observed ciliates with atypical morphology but with diagnostic features of genus Diploplastron. This study describes Diploplastron dehorityi, a new species of ophryoscolecid ciliate, that differs from D. affine, primarily, in the morphology of skeletal plates, morphology of nuclear apparatus and body shape. In addition to the similarities between the new species and congener species, D. dehorityi has some morphological similarities to species of genus Eremoplastron.

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