https://search.dev.ndltd.org/etd/massey/oai:mro.massey.ac.nz:10179/4628
type: CreativeWork
name: Some aspects of meiosis in normal and Robertsonian translocation-carrying rams : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Veterinary Science at Massey University
description: SOME ASPECTS OF MEIOSIS IN NORMAL AND ROBERTSONIAN TRANSLOCATION-CARRYING RAMS A study was made of the meiotic chromosomes in air-dried preparations from 35 genitally sound rams (Ovis aries). The quantity and quality of dividing cells were best when testicular material was obtained by castration under local anaesthesia from rams during their breeding season. Sodium tri-citrate solution was used as hypotonic treatment and the cells were fixed in suspension with glacial acetic acid and absolute alcohel plus a trace of chloreform. Slides were stained either with aceto-orcein or with Giemsa for a "C-banding" technique. Fourteen of the rams bad a normal mitotie karyetype (54,xy) and the remainder were heterozygous or homozygous carriers of a Massey I, Massey II or Massey III Robertsonian translocation and had the following mitotic karyotypes: 53,xy,t(5q26q); 52,xy, t(5q26q) t(5q26q); 53,xy,t(8q11q); 53,xy,t(7q25q); 52,xy, t(7q25q) t (7q25q). One ram was heterozygous for both the Massey I and Massey III Robertsonian translocations. Analysis of primary spermatocyte cells showed that a modal number of 27 chromosomal elements was present in normal rams, while in both heterozygous and homozygous Robertsonian translocation-carriers, a modal number of 26 chromosomal elements was recorded. Heterozygous carriers of the three types of Robertsonian translocations, which involved non-homologous chromosomes, were characterized by the presence of a trivalent in cells at the diplotene, diakinesis and metaphase I stages. The modal number of chromosomal elements was recorded in over 80 per cent of the cells at diakinesis and metaphase I in the heterozygous and normal rams while over 77 per cent of the cells in the Massey I homozygote and 90 per cent of the cells in the Massey III homozygote had modal counts. An association between the sex bivalent and a small autosomal bivalent was recorded in 7.5 per cent of the diakinesis-metaphase I cells from normal rams and in between 3.4 and 4.7 pe…
abstract: SOME ASPECTS OF MEIOSIS IN NORMAL AND ROBERTSONIAN TRANSLOCATION-CARRYING RAMS A study was made of the meiotic chromosomes in air-dried preparations from 35 genitally sound rams (Ovis aries). The quantity and quality of dividing cells were best when testicular material was obtained by castration under local anaesthesia from rams during their breeding season. Sodium tri-citrate solution was used as hypotonic treatment and the cells were fixed in suspension with glacial acetic acid and absolute alcohel plus a trace of chloreform. Slides were stained either with aceto-orcein or with Giemsa for a "C-banding" technique. Fourteen of the rams bad a normal mitotie karyetype (54,xy) and the remainder were heterozygous or homozygous carriers of a Massey I, Massey II or Massey III Robertsonian translocation and had the following mitotic karyotypes: 53,xy,t(5q26q); 52,xy, t(5q26q) t(5q26q); 53,xy,t(8q11q); 53,xy,t(7q25q); 52,xy, t(7q25q) t (7q25q). One ram was heterozygous for both the Massey I and Massey III Robertsonian translocations. Analysis of primary spermatocyte cells showed that a modal number of 27 chromosomal elements was present in normal rams, while in both heterozygous and homozygous Robertsonian translocation-carriers, a modal number of 26 chromosomal elements was recorded. Heterozygous carriers of the three types of Robertsonian translocations, which involved non-homologous chromosomes, were characterized by the presence of a trivalent in cells at the diplotene, diakinesis and metaphase I stages. The modal number of chromosomal elements was recorded in over 80 per cent of the cells at diakinesis and metaphase I in the heterozygous and normal rams while over 77 per cent of the cells in the Massey I homozygote and 90 per cent of the cells in the Massey III homozygote had modal counts. An association between the sex bivalent and a small autosomal bivalent was recorded in 7.5 per cent of the diakinesis-metaphase I cells from normal rams and in between 3.4 and 4.7 pe…
author: Chapman, Helen Margaret
keywords: Meiosis, Sheep, Rams
date published: 1974
date modified: 2026-07-27T20:17:35Z
provider: Massey University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Massey University