Endocrine relationships in the induction of oestrus and ovulation in the anoestrous ewe

1955 ◽  
Vol 46 (1) ◽  
pp. 37-43 ◽  
Author(s):  
T. J. Robinson
Keyword(s):  
Single Dose ◽  
Benzyl Alcohol ◽  
Artificial Insemination ◽  
Quantitative Data ◽  
Single Injection ◽  
Physiological Activity ◽  
Aqueous Suspension ◽  
Successful Pregnancy ◽  
Oestradiol Benzoate ◽  
Pregnant Mare Serum Gonadotrophin

1. A total of forty-two Suffolk cross-bred and 230 stud Romney Marsh ewes were used in four experiments in which pregnant mare serum gonadotrophin (p.m.s.) was used in various combinations with progesterone and oestrogen in attempts to induce fertile mating in anoestrus.2. Groups of six Suffolk cross-bred ewes were injected with 1000 i.u. p.m.s. after pretreatment, commencing 4 days earlier, with 75 mg. progesterone administered in one of four different ways. Six twice-daily injections in oil resulted in oestrus in five ewes in each of two groups treated. Single injections in oil solution, aqueous suspension, and benzyl alcohol emulsion resulted in oestrus in two, nil, and four ewes, respectively. All were served within 48 hr. of injection of p.m.s.3. Ovulation was observed in five of six crossbred ewes which received six twice-daily injections of progesterone in oil, without subsequent injection of p.m.s. Three were served.4. Divided injections of progesterone commencing 4 days before 750–1000 i.u. p.m.s. failed to induce a satisfactory oestrous response in Romney Marsh ewes. An increase to 7 days in the duration of progesterone stimulation resulted in oestrus in all of eighteen ewes treated.5. The injection of a benzyl alcohol emulsion containing 75 or 150 mg. progesterone, given as a single dose 4 or 7 days before 750 i.u. p.m.s., failed to induce a satisfactory oestrous response. Of seventy-two ewes treated, only seven were served.6. Lambing results were most unsatisfactory when progesterone-p.m.s. treatment was followed by artificial insemination. Of 144 Romneys inseminated, only twelve lambed. Successful pregnancy appeared unrelated to the type of treatment or the occurrence of oestrus.7. On the basis of the oestrous responses observed after the injection of a variety of combinations of oestrogen, progesterone, and p.m.s., and by reference to quantitative data on progesterone-oestrogen relationships in oestrous behaviour in the spayed ewe, it is concluded that the developing follicle of the Romney Marsh ewe produces an amount of oestrogen approximately equivalent, in its physiological activity, to a single injection in oil of about 20 μg. oestradiol benzoate.

STUDIES ON THE MECHANISM OF DECIDUALIZATION. I.

1963 ◽  
Vol 42 (2) ◽  
pp. 225-232 ◽  
Author(s):  
M. C. Shelesnyak ◽  
Peretz F. Kraicer ◽  
Gerard H. Zeilmaker
Keyword(s):  
Single Dose ◽  
Single Injection

ABSTRACT The concept of an oestrogen surge as a prerequisite for successful decidualization of the progravid uterus and consequently nidation in the rat was tested. Experiments were designed to see whether administration of an oestrogen antagonist at specific times would block decidualization (and nidation); whether the ovary was the source of the oestrogen, and whether a single dose of oestrogen, in the absence of the ovary (if the ovary is the source) would allow the uterus to respond to a decidualizing stimulus. It was found that when given prior to the surge, the oestrogen antagonist prevented decidualization and interfered with nidation. The ovary is thus the source of the oestrogen; and a single injection of oestradiol can act as a substitute for the surge.

Liver preneoplastic changes in mice treated with the herbicide fomesafen

1999 ◽  
Vol 18 (5) ◽  
pp. 338-344 ◽  
Author(s):  
J Krijt ◽  
P Stránská ◽  
J Sanitraák ◽  
A Chlumská ◽  
F Fakan
Keyword(s):  
Single Dose ◽  
Single Injection ◽  
Diphenyl Ether ◽  
Liver Histology ◽  
Mouse Strains ◽  
Toxicological Evaluation ◽  
Liver Nodules ◽  
Icr Mice ◽  
Mice Liver ◽  
Foci Of Altered Hepatocytes

1 Effect of the diphenyl ether herbicide fomesafen on liver preneoplastic changes and porphyrin biosynthesis was examined in male C57BL/6J mice (0.23% in the diet for 14 months) and ICR mice (0.3% in the diet for 50 weeks). Fomesafen treatment resulted in preneoplastic changes (liver nodules and foci of altered hepatocytes) in both strains, uroporphyria developed only in ICR mice. 2 Iron pretreatment (600 mg/kg as a single dose) accelerated the development of fomesafen-induced preneoplastic changes in both mouse strains. The number of foci containing altered hepatocytes, as well as the number and size of liver nodules, were increased in iron-pretreated animals. 3 A single injection of iron induced marked uroporphyria in C57BL/6J mice after 14 months (liver porphyrin content 102 nmol/g). This uroporphyria was further potentiated by fomesafen administration (208 nmol/g). 4 In ICR mice, liver histology was apparently normal after a 3 month recovery from fomesafen treatment (0.32% for 9 months). Liver porphyrin content (260 nmol/g) started to decrease immediately after fomesafen withdrawal, but was still significantly elevated after 3 months (5 nmol/g), as compared to controls (1 nmol/g). 5 It is concluded that the toxicological evaluation of fomesafen should focus on liver porphyrin biosynthesis.

Efficiency of mating, artificial insemination or resynchronisation at different times after first timed artificial insemination in postpartum Nellore cows to produce crossbred calves

2019 ◽  
Vol 59 (2) ◽  
pp. 225 ◽  
Author(s):  
Walvonvitis Baes Rodrigues ◽  
Jean do Prado Jara ◽  
Juliana Correa Borges ◽  
Luiz Orcirio Fialho de Oliveira ◽  
Urbano Pinto Gomes de Abreu ◽  
...  
Keyword(s):  
Pregnancy Rate ◽  
Breeding Season ◽  
Chorionic Gonadotropin ◽  
Artificial Insemination ◽  
Fixed Time ◽  
Beef Cows ◽  
Device Removal ◽  
Oestradiol Benzoate ◽  
Timed Artificial Insemination ◽  
Equine Chorionic Gonadotropin

The objective of this trial was to evaluate different post-timed artificial insemination (TAI) reproductive managements in postpartum beef cows to produce crossbred calves from artificial insemination (AI). Nellore cows (n = 607), with 45 days postpartum, were inseminated at a fixed time, using a protocol that included an intravaginal progesterone-releasing device along with oestradiol benzoate, prostaglandin, equine chorionic gonadotropin, and oestradiol cypionate, followed TAI 48 h post-device removal. Four post-TAI treatments were evaluated: in CONTROL (T1, n = 161), cows were exposed to Nellore clean-up bulls until the end of the breeding season (75 days). In OBSERVATION (T2, n = 132), heat detection was performed for 15–25 days post-TAI, followed by AI. In RESYNC22 (T3, n = 157) and RESYNC30 (T4, n = 157), resynchronisation started after 22 or 30 days, following second TAI at Day 32 or 40 days after first TAI. In T2, T3 and T4, after the second AI, cows were exposed to Nellore clean-up bulls until the end of the breeding season (75 days). The pregnancy rate (PR) for the first TAI did not differ (54.6%, 53.0%, 59.2%, and 51.6% for CONTROL, OBSERVATION, RESYNC 22, and RESYNC 30, respectively; P = 0.66), and no difference was observed for the second TAI (RESYNC 22 = 45.31% and RESYNC30 = 46.05%; P = 0.137), in the PR at the end of the breeding season (86.33%, 86.36%, 78.98%, and 81.52%, P = 0.43), or embryonic losses (4.54%, 2.85%, 6.45% and 7.40%, respectively; P = 0.61), but the percentage of crossbred pregnancy was higher in groups with resynchronisation (RESYNC22 and RESYNC30) than CONTROL and OBSERVATION (98.38%, 90.62%, 63.30%, 78.95%, P < 0.001). In conclusion, resynchronisation programs of 22 or 30 days are more efficient to produce AI products, and the final pregnancy rate is similar among the treatments, differing only in the amount of calves produced by AI.

scholarly journals EVALUASI TINGKAT KEBERHASILAN PELAKSANAAN PROGRAM INSEMINASI BUATAN SAPI PERANAKAN FRISIEN HOLSTEIN (PFH) DI DESA SEMEN KECAMATAN GANDUSARI KABUPATEN BLITAR

2018 ◽  
Vol 12 (2) ◽  
pp. 41-47
Author(s):  
Yuli Masfufah ◽  
Edya Moelia Moeis ◽  
Anang Widigdyo
Keyword(s):  
Success Rate ◽  
Artificial Insemination ◽  
Quantitative Data ◽  
Research Method ◽  
Secondary Data ◽  
Data Types ◽  
Average Value ◽  
Pregnant Females ◽  
Data Realization ◽  
The Village

The main objective of this study was to evaluate the success rate of Artificial Insemination (IB) in the Village of Semen Gandusari District, Blitar Regency. This research method is done in 2 ways, namely, descriptive and quantitative analytical. Quantitative data types are data in the form of numbers including: Number of IB services, number of females in IB, all pregnant females IB results, number of pregnant females first IB results, Data Realization of Artificial Insemination activities and recapitulation data on Artificial Insemination births, Number of Days / Months between one birth and the next, the number of farmers applying the IB program. The type of data used is primary and secondary data. The results of the research in the form of primary and secondary data obtained qualitatively are processed descriptively, while the quantitative ones are processed statistically with an average value then interpreted according to the statistics. The results that have been obtained evaluating the success rate of IBs in the working area of Semen KUD, especially Semen village, are as follows: Non Return Rate (NRR) 38.42 ± 32.91%, Conception Rate (CR) 38.42 ± 32.91%, Service Per Conception (S / C) 2.23 ± 0.95 times, 433.2 ± 57.3 days of Calving Interval (CI). It can be concluded that dairy cows in the Semen village pretty good value even though not optimal. Suggestions that need to be carried out further research on factors that influence the success of artificial insemination programs (IB).

Effects of a Single Dose of Rabbit Anti-mouse Lymphocyte Serum on Tumors Induced in Mice by 7,12-Dimethylbenz (a) anthracene Given at Birth

1972 ◽  
Vol 58 (6) ◽  
pp. 397-408 ◽  
Author(s):  
Carlo D. Baroni ◽  
Pietro Mingazzini ◽  
Paolo Pesando ◽  
Anna Cavallero ◽  
Stefania Uccini ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Single Dose ◽  
Malignant Lymphoma ◽  
Single Injection ◽  
Latency Period ◽  
Skin Tumors ◽  
Rabbit Serum ◽  
Normal Rabbit Serum ◽  
Malignant Lymphomas ◽  
Mouse Lymphocyte

The effects of ALS (anti-lymphocyte serum) and NRS (normal rabbit serum) treatments on the development of malignant lymphoma, lung, subcutaneous and skin tumors induced in mice by 7,12-dimethylbenz (a) anthracene (DMBA) are described. Groups of Charles-River mice, injected at birth with a dose of 100 μg of DMBA, received a single injection of ALS or NRS at the same time as DMBA administration or 10, 20, 30, 40 and 50 days after birth. Incidence, latency, histology and spread of the tumors were studied in all groups. It was found that both ALS and NRS increased tumor incidence and shortened their latency period. Malignant lymphomas were the main tumors whose latency was shortened either by ALS or NRS treatment. In addition ALS treatment apparently increased dissemination of DMBA induced lymphoma in bone marrow.

RESTORATION BY OESTRADIOL BENZOATE OF A NEURAL AND HORMONAL RHYTHM IN THE OVARIECTOMIZED RAT

1975 ◽  
Vol 64 (1) ◽  
pp. 27-35 ◽  
Author(s):  
F. R. BURNET ◽  
P. C. B. MACKINNON
Keyword(s):  
Single Injection ◽  
Time Of Day ◽  
Ovariectomized Rats ◽  
Female Rat ◽  
Functional Link ◽  
Initial Injection ◽  
Oestradiol Benzoate ◽  
Before And After ◽  
Lh Release ◽  
The Brain

SUMMARY The rate of [35S]methionine incorporation into protein in discrete cerebral areas was measured before and after the administration of oestradiol benzoate (OB) to chronically ovariectomized rats. The circadian rhythm of incorporation which is normally seen in the intact cyclic female rat was deleted by ovariectomy. A daily rhythm of incorporation reappeared, however, in all the brain areas studied 30 h after a single injection of OB (20 μg), and was still present 12 days later. The release of luteinizing hormone (LH) after administration of 20 μg OB was measured in chronically ovariectomized animals and was found to be biphasic. High levels of LH after ovariectomy were initially reduced by negative feedback, but this phase was followed 52 h later by a facilitation of LH release between 15.00 and 18.00 h. The facilitation of LH release at this time of day was still detectable 12 days after the initial injection. The evidence for a functional link between the rhythm of neural activity which is reflected by [35S]methionine incorporation, and the ability to 'time' the facilitation of LH release is discussed.

In Vivo Effect of Heparin on Acid and Alkaline Ribonuclease Activities of Mouse Liver

1956 ◽  
Vol 184 (2) ◽  
pp. 415-417 ◽  
Author(s):  
Gaston De Lamirande ◽  
George Weber ◽  
Antonio Cantero
Keyword(s):  
Tissue Culture ◽  
Body Weight ◽  
Single Dose ◽  
Ribonucleic Acid ◽  
Mouse Liver ◽  
Single Injection ◽  
Coagulation Time ◽  
Alkaline Ribonuclease ◽  
Blood Coagulability

A single dose of 30 µg/gm body weight of depo-heparin was injected subcutaneously into white Swiss mice. At 1, 3, 6 and 12 hours after the injection, the blood coagulation time was measured and the activity of acid and alkaline ribonuclease of liver was determined. This single injection of depo-heparin significantly inhibited the acid and alkaline ribonucleases of liver 1 hour after injection. The enzymatic activities significantly increased after the blood coagulability was restored. The in vivo inhibition of acid and alkaline ribonuclease activity supports the explanation that the accumulation of ribonucleic acid in cells of tissue culture in the presence of heparin might be due to the inhibition of ribonuclease.

Does oxytocin play a role in the onset of maternal behaviour in the rat?

1984 ◽  
Vol 101 (3) ◽  
pp. 353-357 ◽  
Author(s):  
E. L. M. Bolwerk ◽  
H. H. Swanson
Keyword(s):  
Wistar Rats ◽  
Single Injection ◽  
Rapid Onset ◽  
Maternal Responsiveness ◽  
Control Group ◽  
Maternal Behaviour ◽  
Sprague Dawley ◽  
Untreated Control Group ◽  
Sprague Dawley Rats ◽  
Oestradiol Benzoate

ABSTRACT Oxytocin is released during parturition and may also play a role in maternal behaviour. Oxytocin, injected in the cerebral ventricles, has been reported to accelerate the onset of maternal behaviour in oestrogen-pretreated virgin Sprague—Dawley rats within 2 h of injection. This study was an attempt to replicate and extend these findings in Wistar rats. In the first experiment, 16 virgin females were ovariectomized and a cannula was placed into the cerebral ventricle. Forty-eight hours after a single injection of 24 μg oestradiol benzoate (OB), 400 ng oxytocin or saline were injected into the ventricle. In the second experiment three groups were observed: an untreated control group plus two ovariectomized and cannulated groups treated with OB in a regimen designed to mimic pregnancy. After 10 days of OB administration they received an injection of either saline or oxytocin (400 ng) into the ventricle. Immediately after this injection they were exposed to the pups and observations started. In both experiments no rat became maternal in the first 1·5 h after the intracerebroventricular injection. Oxytocin therefore did not induce a rapid onset of maternal responsiveness in oestrogen-pretreated Wistar rats. J. Endocr. (1984) 101, 353–357

SENSITIVITY OF ANTERIOR HYPOTHALAMIC AREAS TO GONADAL STEROID IMPLANTATION IN ANDROGENIZED FEMALE RATS

1977 ◽  
Vol 74 (2) ◽  
pp. 315-NP ◽  
Author(s):  
A. DANGUY ◽  
J. L. PASTEELS ◽  
F. ECTORS
Keyword(s):  
Single Injection ◽  
Mammary Glands ◽  
Prolactin Secretion ◽  
Female Rats ◽  
Male Rats ◽  
Control Synthesis ◽  
Normal Female ◽  
Immunofluorescence Studies ◽  
Oestradiol Benzoate ◽  
Stimulation Of

A single injection of 1 mg of a complex of testosterone esters on day 5 of life was used to prepare constantly oestrous rats. Such androgenized female rats were then ovariectomized and submitted to stereotaxical implantation of 1 μg oestradiol benzoate, 5 μg testosterone isobutyrate or, as a control, 10 μg cholesterol in the anterior hypothalamic areas. The effects of the steroids on plasma and pituitary FSH and LH were assessed by radioimmunoassay. As reported previously by us in normal female and male rats, the preoptic–suprachiasmatic area (POA) was able to control synthesis and secretion of both gonadotrophins and did not lose its sensitivity to oestradiol and testosterone in androgenized rats. Evidence for enhanced prolactin secretion in androgenized rats was derived from immunofluorescence studies of the pituitary gland and from histology of the mammary glands. In this respect the condition of the androgenized females was opposite to that of the males. The present work demonstrated that stimulation of prolactin secretion in androgenized female rats resulted from oestrogen action due to permanent oestrus rather than from impairment of hypothalamo-hypophysial relationships. Indeed, prolactin stimulation was suppressed when the androgenized rats were ovariectomized and restored when they were subsequently implanted with oestradiol in the POA.

Peripubertal changes in the nature of LH

1985 ◽  
Vol 104 (2) ◽  
pp. 173-177 ◽  
Author(s):  
J. C. Buckingham ◽  
C. A. Wilson
Keyword(s):  
Biological Activity ◽  
Pituitary Gland ◽  
Leydig Cells ◽  
Abrupt Change ◽  
Single Injection ◽  
Full Spectrum ◽  
Luteinizing Hormone Releasing Hormone ◽  
Cytochemical Bioassay ◽  
Pregnant Mare Serum Gonadotrophin

ABSTRACT Administration of pregnant mare serum gonadotrophin (PMSG) to peripubertal rats, aged 27 days, induces ovulation provided the animals weigh more than 60 g at the time of the injection. In an attempt to determine whether the apparent immaturity of the ovaries in smaller rats is associated with an inability of the pituitary gland to secrete LH, the biological and immunological properties of LH in peripubertal PMSG-treated rats were examined. A single injection of PMSG caused a marked hypersecretion of LH in rats aged 27 days. The LH in the plasma of rats weighing more than 60 g was active in both the radioimmunoassay and the cytochemical bioassay but that in smaller rats was active only in the former. Plasma from both groups of rats stimulated the release of testosterone from dispersed Leydig cells. Luteinizing hormone-releasing hormone stimulated the secretion, in vitro, of immunoreactive, cytochemically active LH by pituitary tissue from rats weighing over 60 g. The LH released in vitro from tissue from the smaller animals, like that in their plasma, was active in the radioimmunoassay but not in the cytochemical system. The results suggest that an abrupt change in the nature of LH occurs at puberty and that ovulatory cycles commence only when the pituitary gland secretes the adult form of LH with a full spectrum of biological activity. J. Endocr. (1985) 104, 173–177

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