IDENTIFICATION OF OVARIAN FOLLICLES AT ESTRUS AND DEVELOPMENT OF THEIR ENSUING CORPORA LUTEA IN SINGLE AND MULTIPLE OVULATING EWES ON TWO FEEDING REGIMES

1977 ◽  
Vol 57 (4) ◽  
pp. 647-652 ◽  
Author(s):  
J. J. DUFOUR ◽  
P. MATTON
Keyword(s):  
High Energy ◽  
Ovarian Follicles ◽  
Low Energy ◽  
Ovulation Rate ◽  
Corpora Lutea ◽  
The Third ◽  
India Ink ◽  
Feeding Regimes

Twelve hours after standing estrus was first detected, 30 ewes had their four largest follicles identified and marked with India ink. Seven days later, ovulation rates and origin of the corpora lutea (CL) from previously marked follicles were determined. Feeding a high energy ration from day 10 to estrus did not change the ovulation rate as compared to feeding a low energy ration. Its only effect was to increase the diameter of the third and fourth largest follicles. The diameter of the largest follicle was identical in single and multiple ovulators. However, in multiple ovulators, the diameter of the second largest follicle was larger than in single ovulators. The largest follicle identified at estrus developed into a CL that was 15% heavier in single than in multiple ovulators. In multiple ovulators, the second largest follicle developed into a CL of weight similar to that from the largest follicle.

scholarly journals MORPHOLOGY AND RESPONSIVENESS OF THE TWO LARGEST OVARIAN FOLLICLES IN ANESTROUS EWES

1977 ◽  
Vol 57 (3) ◽  
pp. 459-464 ◽  
Author(s):  
PIERRE MATTON ◽  
JACQUES BHÉREUR ◽  
J. J. DUFOUR
Keyword(s):  
Breeding Season ◽  
Ovarian Follicles ◽  
Ovulation Rate ◽  
Corpora Lutea ◽  
India Ink

The morphology and the responsiveness of ovarian follicles to an ovulating stimulus imposed in the presence or absence of previously induced corpora lutea (CL) were studied in anestrous DLS ewes (Dorset × Leicester × Suffolk). Induction of CL formation was done with 500 IU of PMSG given intravenously. In CL-bearing ewes, the diameter of the largest follicle was significantly larger 12 and 16 days after PMSG injection, while that of the second largest follicle was increased only on day 12. When ovulation was induced with 500 IU PMSG on day 16, the presence of a previously induced CL did not modify the ovulation rate. The two largest follicles identified with India ink markings 4 days prior to PMSG injection did not respond by ovulation and most of these follicles had become completely atretic by day 21 of the experiment. When the two largest follicles, however, were identified and marked on the day of PMSG injection, 65% of them responded to the stimulus. This indicated that turnover of the large follicles was occurring during the anestrous season as is the case during the normal breeding season.

Prepubertal reduction of the ovarian follicle population by combined LH-releasing hormone antagonist treatment and unilateral ovariectomy influences follicle characteristics but not the ovulation rate at first oestrus

1992 ◽  
Vol 135 (3) ◽  
pp. 439-446 ◽  
Author(s):  
W. A. van Cappellen ◽  
E. C. M. van Leeuwen ◽  
P. Kramer ◽  
H. M. A. Meijs-Roelofs
Keyword(s):  
Ovarian Follicle ◽  
Ovarian Follicles ◽  
Ovulation Rate ◽  
Corpora Lutea ◽  
Normal Range ◽  
Juvenile Period ◽  
Unilateral Ovariectomy ◽  
Releasing Hormone ◽  
Total Pool ◽  
Lh Releasing Hormone

ABSTRACT The effect on first ovulation of the massive reduction of the total pool of ovarian follicles during the infantile and late juvenile period was studied in rats. Treatment with an LH-releasing hormone antagonist (LHRH-A) during infancy (5 mg/kg body weight on days 6, 9, 12 and 15 of life) was combined with unilateral ovariectomy performed on either day 15 (early ULO) or 2–5 days before the expected day of first ovulation (late ULO). Rats were killed on the day of first or second oestrus, when blood was collected and the (remaining) ovaries were prepared for differential counting of follicles and corpora lutea. In addition, blood was sampled 8 h after ULO and the ovaries studied histologically in the group of rats which were unilaterally ovariectomized 2–5 days before first ovulation. The time of first ovulation was not influenced by treatment with LHRH-A, early or late ULO, or a combination of LHRH-A treatment and ULO. Ovulation rate after LHRH-A treatment was decreased, but was still within the normal range in intact rats and in early ULO rats compared with saline-treated controls. Serum FSH concentrations 8 h after ULO performed 2–5 days before first ovulation were similar in saline- and LHRH-A-treated rats (845 ± 59 and 801 ± 99 (s.e.m.) μg/l respectively) and had increased compared with intact controls (216 ± 15 μg/l). Treatment with LHRH-A resulted in a reduction of more than 50% in healthy and atretic follicles, and late ULO reduced the number of healthy follicles even further. In saline-treated rats late ULO decreased the rate of atresia, but in LHRH-A-treated rats atresia was not reduced further by (late or early) ULO. It is concluded that even after massive reduction of the pool of ovarian follicles by early LHRH-A treatment combined with late or early ULO, the timing of the first ovulation was normal and ovulation rates, although somewhat lower in some LHRH-A-treated rats, were within the normal range. Journal of Endocrinology (1992) 135, 439–446

scholarly journals Relation between nutrition and fertility in pigs.

1980 ◽  
Vol 28 (4) ◽  
pp. 211-227 ◽  
Author(s):  
L.A. den Hartog ◽  
G.J.M. van Kempen
Keyword(s):  
Energy Intake ◽  
Early Pregnancy ◽  
Protein Intake ◽  
High Energy ◽  
Low Energy ◽  
Embryonic Mortality ◽  
Ovulation Rate ◽  
High Energy Intake ◽  
Suitable Sequence

A review of experiments on the effect of energy and protein intake on fertility in gilts suggested that a high energy intake shortly before oestrus (flushing) increased ovulation rate. Although high energy intake gave more ovulations than low energy intake, embryonic mortality was greater. The most suitable sequence during rearing, flushing and early pregnancy seemed to be low, high and low energy, respectively. (Abstract retrieved from CAB Abstracts by CABI’s permission)

The effect of increasing feed intake for one day only during the oestrus period on the reproductive performance of sows

1971 ◽  
Vol 13 (4) ◽  
pp. 669-675 ◽  
Author(s):  
P. H. Brooks ◽  
D. J. A. Cole
Keyword(s):  
Reproductive Performance ◽  
Feed Intake ◽  
Ovulation Rate ◽  
Control Group ◽  
Large White ◽  
Embryo Mortality ◽  
The Third ◽  
Feeding Regimes ◽  
Embryo Number

SUMMARYTwo groups of 24 Landrace × Large White gilts were allocated at puberty to two feeding regimes during oestrus. The control group received 1·8 kg food/day throughout the oestrus period, while the flushed group had an additional 1·8 kg immediately after mating on the first day of oestrus. The treatments were imposed at the first post-puberal heat (second heat) and at the post-weaning oestrus in the second and third parities. The sows remained on the same treatment throughout the experiment. Litter performance was measured in the first two parities. The sows were slaughtered on day 25 of their third gestation to provide data on ovulation rate and embryo mortality. Increasing feed intake to 3·6 kg on the day of mating did not significantly affect the number of piglets born, number born live, or mean piglet weight, in either the first or second parity. In the third parity, ovulation rate, embryo number at 25 days of gestation and embryo mortality were unaffected by treatment.

scholarly journals Spring and summer and wool growth pasture feeding and ewe reproduction

1990 ◽  
pp. 123-127 ◽  
Author(s):  
K.F. Thompson ◽  
J.R. Sedcole ◽  
D. O'Connell ◽  
K.G. Geenty ◽  
A.R. Sykes
Keyword(s):  
Ovulation Rate ◽  
Corpora Lutea ◽  
Carryover Effects ◽  
Feeding Level ◽  
The Third ◽  
Wool Growth ◽  
Summer Feeding

Effects of pasture feeding level during lactation and over summer on ewe wool growth and ovulation rate were assessed in 1983-84 and 1984-85. Two levels of pasture feeding (lactation high and lactation low) from parturition to weaning (10 weeks) produced 8 to 10 kg liveweight difference in ewe liveweight at weaning. Groups (n = 40) were offered pasture allowances of 0.8, 1, 1.4, 2 or 5 kg DM/ewe/day from weaning until after the third synchronzied oestrus in April. Ewes on the lower allowances tended to reach a stable liveweight and those on 5 kg DM/ewe/day gained throughout. Other groups were offered low allowances during summer and then 5 kg DM/ewe/day after the first recorded oestrus. Mean dates for synchronised oestrus were 2 March, 19 March and 5 April. Ovulation rate increased by 0.15 corpora-lutea/ewe ovulating at each successive oestrus, and increased by 0.047 corpora lutes/ewe ovulating for each kg increase in liveweight at oestrus. These effects accounted for 77% of the variation in ovulation rate between treatments across years. The effects of flushing, lactation or summer liveweight change were small and generally non-significant. Lactation feeding affected wool growth during lactation as well and had carryover effects through the summer when lactation low ewes grew 10% less wool irrespective of the level of summer feeding. Keywords ewe, wool growth, ovulation rate, lactation, summer feeding, liveweight, flushing

Destinée des deux plus gros follicules des ovaires de brebis à la suite de la destruction du plus gros follicule et/ou de l'enlèvement du corps jaune à deux moments du cycle

1976 ◽  
Vol 54 (1) ◽  
pp. 7-11 ◽  
Author(s):  
Jacques Bhérer ◽  
Jacques DuFour ◽  
Pierre Matton
Keyword(s):  
Inhibitory Effect ◽  
Ovulation Rate ◽  
Corpora Lutea ◽  
India Ink

Marking of the largest (F1) and the second largest (F2) follicles of the ovaries of the sheep with India ink has allowed us to observe the fate of these follicles after different treatments.All the F1 and F2 follicles of the controls marked on the 10th day of the cycle became atretic, but when the marking was done on the 14th day, only the F1 (of the marked follicles) ovulated. Destruction of the F1 with or without removal of the corpora lutea allowed some of the F2 to ovulate, whereas only removal of the corpora lutea decreased the number of F1 ovulating. It thus appears that the fate of the F1 is related to the time of the cycle and that the F1 could have an inhibitory effect on the ovulation of the F2. Removal of the corpora lutea also induced the development of several cystic follicles and decreased the total ovulation rate.

scholarly journals Ovulation Rate and Inhibin Levels in Gonadotrophin-treated Mice

1985 ◽  
Vol 38 (1) ◽  
pp. 115 ◽  
Author(s):  
Victor WK Lee ◽  
William RGibson
Keyword(s):  
Circulatory System ◽  
Ovarian Follicles ◽  
Ovulation Rate ◽  
Corpora Lutea ◽  
Follicular Growth ◽  
Immature Female ◽  
Positive Correlation ◽  
Female Mice ◽  
Ovarian Follicular Growth

Ovarian follicular growth was induced in immature female mice with varying doses of pregnant mare's serum gonadotrophin. The numbers of ovulations were determined either by counting tubal oocytes or corpora lutea in the ovary. Ovarian and circulatory levels of inhibin rose progressively with increasing doses of PMSG and a positive correlation (P < O� 0 I) was found between circulating inhibin levels and ovulation rate. The latter correlation makes it likely that the growing preovulatory ovarian follicles are the predominant source for the secretion of inhibin into the circulatory system.

Low energy vs. high energy depositional settings and related sedimentary bodies in early Senenian rudist bearing carbonate shelves (central-southern Italy)

2001 ◽  
Vol 28 (1) ◽  
pp. 37-40 ◽  
Author(s):  
Gabriele Carannante ◽  
A. Laviano ◽  
D. Ruberti ◽  
Lucia Simone ◽  
G. Sirna ◽  
...  
Keyword(s):  
Southern Italy ◽  
High Energy ◽  
Low Energy ◽  
Depositional Settings

Transportation: Fuel Energies

2017 ◽  
Author(s):  
Peter Rez
Keyword(s):  
Energy Density ◽  
Fossil Fuels ◽  
High Energy ◽  
Ease Of Use ◽  
Low Energy ◽  
High Energy Density ◽  
Nuclear Fuels ◽  
Liquid Hydrocarbons ◽  
Transportation Fuel ◽  
Journey Time

Transportation efficiency can be measured in terms of the energy needed to move a person or a tonne of freight over a given distance. For passengers, journey time is important, so an equally useful measure is the product of the energy used and the time taken for the journey. Transportation requires storage of energy. Rechargeable systems such as batteries have very low energy densities as compared to fossil fuels. The highest energy densities come from nuclear fuels, although, because of shielding requirements, these are not practical for most forms of transportation. Liquid hydrocarbons represent a nice compromise between high energy density and ease of use.

scholarly journals Low-Energy Electron Damage to Condensed-Phase DNA and Its Constituents

2021 ◽  
Vol 22 (15) ◽  
pp. 7879
Author(s):  
Yingxia Gao ◽  
Yi Zheng ◽  
Léon Sanche
Keyword(s):  
Condensed Phase ◽  
Genetic Material ◽  
High Energy ◽  
Dna Lesions ◽  
Low Energy ◽  
Experimental Investigations ◽  
Experimental Conditions ◽  
Strand Breaks ◽  
Sequence Of Events ◽  
Wide Range

The complex physical and chemical reactions between the large number of low-energy (0–30 eV) electrons (LEEs) released by high energy radiation interacting with genetic material can lead to the formation of various DNA lesions such as crosslinks, single strand breaks, base modifications, and cleavage, as well as double strand breaks and other cluster damages. When crosslinks and cluster damages cannot be repaired by the cell, they can cause genetic loss of information, mutations, apoptosis, and promote genomic instability. Through the efforts of many research groups in the past two decades, the study of the interaction between LEEs and DNA under different experimental conditions has unveiled some of the main mechanisms responsible for these damages. In the present review, we focus on experimental investigations in the condensed phase that range from fundamental DNA constituents to oligonucleotides, synthetic duplex DNA, and bacterial (i.e., plasmid) DNA. These targets were irradiated either with LEEs from a monoenergetic-electron or photoelectron source, as sub-monolayer, monolayer, or multilayer films and within clusters or water solutions. Each type of experiment is briefly described, and the observed DNA damages are reported, along with the proposed mechanisms. Defining the role of LEEs within the sequence of events leading to radiobiological lesions contributes to our understanding of the action of radiation on living organisms, over a wide range of initial radiation energies. Applications of the interaction of LEEs with DNA to radiotherapy are briefly summarized.

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