Sources of progesterone during gestation in Barbary sheep (Ammotragus lervia)

1983 ◽  
Vol 98 (2) ◽  
pp. 283-NP ◽  
Author(s):  
A. P. F. Flint ◽  
R. D. Burton ◽  
R. B. Heap

Concentrations of progesterone in arterial and ovarian, uterine and jugular venous plasma were determined in four Barbary sheep at various stages of pregnancy. The results, together with ovarian histology, show that the corpus luteum regresses before term in Barbary sheep, as in most breeds of domestic ewes. Uterine synthesis of progesterone was demonstrated in late pregnancy in two animals in which uterine venous levels of progesterone were increased two- to fourfold above arterial concentrations. The placenta contained 3β-hydroxysteroid dehydrogenase. Barbary sheep (diploid chromosome number, 2N = 58) therefore resemble the domestic sheep (2N = 54) rather than the goat (2N = 60) from the point of view of the source of the progesterone required for maintenance of pregnancy.

1968 ◽  
Vol 107 (6) ◽  
pp. 745-751 ◽  
Author(s):  
G. van Vliet ◽  
T. H. J. Huisman ◽  
G. A. Dasher ◽  
W. H. Moretz ◽  
A. M. Dozy ◽  
...  

1. Two haemoglobin types, haemoglobins Amm-C and Amm-B, were observed in five Barbary sheep (Ammotragus lervia). One animal was homozygous for haemoglobin Amm-C, a second was homozygous for haemoglobin Amm-B, and three were heterozygous for both. 2. Amino acid analyses of the globin from haemoglobin Amm-B showed that this type was related to, but not identical with, haemoglobin B of the domestic sheep. 3. The β-chain of haemoglobin Amm-C was found to be composed of 141 amino acid residues. Its amino acid composition differed from that of the βC-chain of the anaemic domestic sheep in at least 14 residues. The Amm-βC-chain contained one isoleucyl residue. 4. The amino acid compositions of tryptic peptides T-1, T-2, T-13 and T-14 of the Amm-βC-chain were similar to those of the sheep βC-chain. Peptides T-3, T-4, T-6, T-7, T-8, T-11 and T-15 were the same as the corresponding peptides of the sheep βA- and βC-chains. Peptide T-5 and to a smaller extent peptide T-9 resembled the corresponding peptides of the sheep βA-chain, and peptide T-10 was identical with peptide γT-10 of sheep haemoglobin F. Peptide T-12 was not recovered. 5. The results of these investigations were interpreted as being indicative that the structural Amm-βC-gene is closely related to the βC-gene of sheep, from which through domestication the present domestic sheep originated.


Zootaxa ◽  
2012 ◽  
Vol 3313 (1) ◽  
pp. 53 ◽  
Author(s):  
HAILIN YANG ◽  
HU LI ◽  
XUN DAI ◽  
JIAN CHANG ◽  
WANZHI CAI

Some cytogenetic aspects of six Chinese species of Coreoidea were studied. The material included five species from the familyCoreidae: Hydarella orientalis (Distant), Homoeocerus bannaensis Hsiao, Cletus graminis Hsiao & Cheng, Paradasynus lon-girostris Hsiao, Acanthocoris scaber (Linnaeus), and one species from the family Stenocephalidae: Stenocephalus femoralisReuter. All species show holokinetic chromosomes, post-reductional meiotic division of XO sex chromosomes, a pre-reduc-tional type of meiosis for autosomes and m-chromosomes, intersticial chiasmata in most autosomes, and one chiasma per biva-lent in male meiosis. In the species studied, the diploid chromosome number ranged from 13 to 21. It was 13 in S. femoralis (10+ 2m + XO), 15 in Hy. orientalis (12 + 2m + XO), 17 in Ho. bannaensis (14 + 2m + XO) and C. graminis (14 + 2m + XO), 19in P. longirostris (16 + 2m + XO), and 21 in A. scaber (18 + 2m + XO). Hy. orientalis represents the first cytogenetically stud-ied species in subfamily Hydarinae. The phylogenetic relationships among Coreoidea are briefly discussed from a cytogenetic point of view.


Author(s):  
Guillermo E. Delgado-de las Cuevas ◽  
Petras Prakas ◽  
Eglė Rudaitytė-Lukošienė ◽  
María L. García-Gil ◽  
Manuel Martínez-González ◽  
...  

Phytotaxa ◽  
2016 ◽  
Vol 273 (2) ◽  
pp. 141 ◽  
Author(s):  
EUGENY V. BOLTENKOV

Iris aphylla Linnaeus (1753: 38) (Iridaceae) is a highly variable species from the morphological point of view, especially in the height of stem, stem branching, size of leaves, and color of flowers. Moreover, it can be found in different habitats. In the Middle-Russian Upland, this plant is mostly associated with meadow steppes on slopes and, rarely, with edges of shrub thickets; also occurs along forest edges and in open forests, where blooming plants are rare (Kazakova et al. 2015). It is native to Central, Eastern, and some parts of Western Europe. The species is widespread in the Ukraine and mainly in the south of middle European Russia, while in the European countries its populations are sparser. Iris aphylla is of autotetraploid origin (Mitra 1956); plants with the chromosome number 2n = 48 are found more frequently in Europe (Wróblewska et al. 2010). Its numerous synonyms, including four subspecies, indicate the variability of this species. The genetic data confirm the conclusion that the subspecies of I. aphylla should be regarded as a single species (Wróblewska et al. 2010). According to my best knowledge (see also Jarvis 2007) the name I. aphylla is still lacking typification.


1975 ◽  
Vol 65 (1) ◽  
pp. 117-125 ◽  
Author(s):  
M. R. MANN ◽  
L. B. CURET ◽  
A. E. COLAS

SUMMARY Placental microsomes from eight domestic sheep at 136–146 days of gestation were incubated with radioactive androstenedione, testosterone and dehydroepiandrosterone. Aromatizing activity was examined in the presence and absence of cortisol and the rates of both oestrone and oestradiol synthesis were measured. Oestrone predominated in preference to oestradiol in most of the incubations, a result opposite to that found with human placentae. The sharp increase in the rate of oestradiol production found in the 144- to 146-day-old placentae incubated with testosterone may indicate a more rapid increase of aromatizing than of 17β-hydroxysteroid dehydrogenase activity. The presence of cortisol in the mixtures did not significantly affect the placental aromatizing activity, indicating that there is no direct effect of cortisol on the enzyme system as measured in vitro. The dramatic rise of overall mean aromatizing activity from 4·86 ± 0·22 (s.e.m.) at 138–141 days of gestation to 12·96 ± 0·38 pmol/mg protein/min at 144–146 days (with a greater relative increase in the rate of oestradiol formation), suggests that changes in placental aromatizing activity may play an important role in maternal and foetal plasma oestrogen surges before ovine parturition.


1987 ◽  
Vol 113 (1) ◽  
pp. 97-101 ◽  
Author(s):  
M. J. Taylor

ABSTRACT An inhibitor of 3β-hydroxysteroid dehydrogenase (3β-HSD) activity was administered to sheep in late pregnancy. A rapid fall in plasma progesterone concentrations followed, associated with premature delivery by all animals 44±3 h (s.e.m.) after administration of inhibitor. A significant (about twofold) increase in plasma concentrations of oestradiol-17β was detected immediately before delivery. These results demonstrate, in contrast to previous reports, that 3β-HSD inhibitors have the capacity consistently to induce premature delivery associated with increased oestrogen release in sheep. J. Endocr. (1987) 113, 97–101


2018 ◽  
Vol 70 (3) ◽  
pp. 443-447
Author(s):  
Jelena Blagojevic ◽  
Marija Rajicic ◽  
Vladimir Jovanovic ◽  
Tanja Adnadjevic ◽  
Ivana Budinski ◽  
...  

Arvicoline voles are known as a karyotypically extremely polymorphic group in which the genus Microtus leads with the highest rate of karyotype change. A member of this genus, the European pine vole Microtus subterraneus (de Selys-Longchamps, 1836), is widely distributed in Europe and parts of Asia. There are two cytotypes differing in diploid chromosome number, 2n=54 and 52, each showing different chromosomal polymorphisms. At two localities in southeastern Serbia, Mt. Jastrebac and Vlasina, we found the 2n=52 cytotype. Meiotic preparations from males revealed the presence of asynaptic sex chromosomes. Although asynaptic sex chromosomes are frequent in Microtus, this is the first finding for M. subterraneus. From summarized data it appears that two-thirds of the studied species, mainly from Microtus and Terricola subgenera, possess asynaptic sex chromosomes.


1959 ◽  
Vol 12 (4) ◽  
pp. 385-388
Author(s):  
Yoshitomi Takano ◽  
Masahiko Seki ◽  
Atushi Urago ◽  
Yoshio Kaneko ◽  
Tadao Moritomo ◽  
...  

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