Effects of levonorgestrel on ovulation and oestrous behaviour in the female tammar wallaby

2007 ◽  
Vol 19 (2) ◽  
pp. 335 ◽  
Author(s):  
Emily F. Hynes ◽  
Chris D. Nave ◽  
Geoff Shaw ◽  
Marilyn B. Renfree

Subcutaneous hormone implants are a useful method for managing overabundant marsupials in restricted enclosures in Australia. Levonorgestrel induces long-term infertility in the kangaroo, tammar wallaby and koala, although the contraceptive mechanism of levonorgestrel is unknown for any marsupial. In the present study, it was investigated if insertion of a single levonorgestrel or control implant at the time of reactivation of the diapausing blastocyst affected the subsequent post-partum oestrus or the preceding follicular development. Twenty levonorgestrel-treated and 16 control animals were autopsied the day before birth and the accompanying post-partum oestrus (Day 25), and 10 levonorgestrel-treated and five of the nine control animals were autopsied 3–4 days (Days 29–30) after the expected birth and oestrus. Peripartum behaviour was observed and birth and mating times were recorded. Levonorgestrel treatment did not prevent follicular growth because there was no significant difference between treatment and control animals in the size of the dominant follicle at Day 25. None of the levonorgestrel-treated females autopsied at Days 29–30 had ovulated (n = 10), in contrast to controls, where four of the five that were autopsied had ovulated. Mating occurred in eight of nine control animals but in only three of 10 levonorgestrel-treated females. Males showed a more sustained period of interest in the three that were mated than in the controls, and mating took place significantly later after birth (36 v. 10 h; P = 0.038). Follicular growth and development was not blocked in any female but only one-third of the animals mated and none ovulated after levonorgestrel treatment. These results suggest that levonorgestrel inhibits the preovulatory surge of luteinising hormone.

1991 ◽  
Vol 9 (5) ◽  
pp. 736-740 ◽  
Author(s):  
L E Spitler

We conducted a long-term follow-up (median, 10.5 years) of patients included in a randomized trial of levamisole versus placebo as surgical adjuvant therapy in 203 patients with malignant melanoma. Of the patients randomized, 104 received levamisole, and 99 received placebo. The results show that there is no difference between the treatment and control groups with regard to any of the three end points analyzed. These included disease-free interval, time to appearance of visceral metastasis, and survival. Moreover, there was no significant difference between the treatment and control groups after adjusting for age, sex, or stage of disease.


2021 ◽  
Author(s):  
Vildan Güngörer ◽  
Mehmet Öztürk ◽  
Mustafa Yasir Özlü ◽  
Şükrü Arslan

ABSTRACT Objectives Long-term therapy with low-dose methotrexate (MTX) is widely used in treatment of rheumatic diseases, in children. The purpose of this study was to evaluate liver elasticity in patients with juvenile idiopathic arthritis (JIA) who received MTX and compare the results with control group. Methods Liver elasticity was evaluated with shear wave elastography (SWE) technique in 25 patients aged 3–17 years who were followed up with JIA and received MTX and compared with 25 healthy controls of the same age and weight. Factors that had an effect on liver elasticity were examined. Results The mean SWE value of patients was 2.64 ± 2.13 m/s and 24.10 ± 18.50 kPa, whereas 1.83 ± 0.16 m/s and 10.09 ± 1.83 kPa in control group. There was a significant difference in liver elasticity in the patient and control groups. When the patients were evaluated as Group 1 (< 1000 mg) and Group 2 (≥ 1000 mg) according to the cumulative MTX dose, no significant difference was obtained. There was positive correlation between liver elasticity and weekly MTX dose and age. Conclusions Our study revealed that liver elasticity significantly decreased in patients who received MTX when compared with the control group. The elastography technique will be understood better over time and used safely in many areas.


Reproduction ◽  
2004 ◽  
Vol 127 (2) ◽  
pp. 265-273 ◽  
Author(s):  
C A Herbert ◽  
T E Trigg ◽  
D W Cooper

The effect of treatment with slow release implants containing the GnRH agonist, deslorelin, was investigated in female tammar wallabies. Pouch young were removed from 16 wallabies presumed to be carrying quiescent blastocysts. Eight received a 5 mg deslorelin implant and eight received a placebo implant. Animals were caught daily from day 25 to day 30 and their pouches inspected for newborn young and their urogenital sinus checked for a copulatory plug. Treatment with deslorelin did not affect reactivation of a dormant blastocyst and subsequent birth in 4/8 animals, but post-partum mating was inhibited in these animals. Five control and five treated animals were killed within 0–48 h post partum and their reproductive tracts analysed. At autopsy, all five control animals had large preovulatory follicles but only one deslorelin-treated animal showed signs of follicular development. These differences were also reflected in the weights of the lateral vaginae, with treated animals showing no evidence of oestrogenic stimulation. The remaining three control and three treated animals were monitored for approximately 2 years. The long-term contraceptive effects of a single 5 mg deslorelin implant lasted for just under one year. These results indicate that slow release deslorelin implants inhibit follicular development in the female tammar wallaby for extended periods of time and may have potential application in reproductive management of captive marsupials in the kangaroo family.


1990 ◽  
Vol 2 (1) ◽  
pp. 79 ◽  
Author(s):  
TP Fletcher ◽  
G Shaw ◽  
MB Renfree

Female tammar wallabies were treated with the dopamine agonist bromocriptine at the end of pregnancy to suppress the peripartum pulse of plasma prolactin. The animals were subsequently observed, and a series of blood samples taken to define the hormonal profiles before and immediately after parturition. Birth was observed in 4/5 control animals and occurred in 8/9 bromocriptine-treated animals. The peripartum peak in plasma PGFM concentrations was not affected by bromocriptine although the pulse of prolactin normally seen at parturition was completely abolished. The timing of luteolysis was apparently unaffected, as plasma progesterone concentrations fell similarly in both treated and control animals immediately after parturition. However, all of the neonates of the bromocriptine-treated animals died within 24 h, possibly because of a failure to establish lactation. Subsequent onset of post-partum oestrus was delayed or absent both in control and in bromocriptine-treated animals, suggesting that the frequent blood sampling and disturbances in the peripartum period interfered with these endocrine processes. It is concluded that both prolactin and prostaglandin can induce luteolysis in the pregnant wallaby, but that the normal sequence of events results from a signal of fetal origin inducing a prostaglandin release from the uterus, which in turn releases a pulse of prolactin that induces a progesterone decline.


2015 ◽  
Vol 27 (1) ◽  
pp. 178
Author(s):  
K. M. Lemes ◽  
L. A. Silva ◽  
E. C. C. Celeghini ◽  
M. A. Alonso ◽  
G. Pugliesi ◽  
...  

The postpartum period is characterised by the rapid uterine involution process and return of ovarian activity (foal heat), resulting in a fertile oestrus in most of the mares. However, the follicular development and selection processes during this period are not completely known in horses. We aimed to study the characteristics of follicular growth and vascular perfusion in the ovary during the early postpartum period in mares that demonstrated oestrous behaviour and had early (<10 days) or late (≥10 days) ovulation. Ten mares were scanned daily from the first day postpartum (Day 1) until the day of the first postpartum ovulation (Day 0). The animals were split in the early (n = 3) and late (n = 7) ovulation groups (averaged interval between parturition and ovulation: 8.0 ± 0.0 and 14.7 ± 1.2 days, respectively). For ultrasound exams a Duplex B-mode and colour Doppler instrument (M5VET®, Mindray, Shenzhen, China) was used with a multifrequency linear probe. Data were analysed for the main effects of group, day, and their interaction using the PROC MIXED procedure of SAS software (version 9.3, SAS Institute Inc., Cary, NC, USA). For the follicular growth, no difference (P > 0.05) was detected between the groups when the data were analysed for the days relative to ovulation (from Day 7 to Day 1). However, the dominant follicle was larger (P < 0.05) in the early-ovulated group (37.2 ± 1.6 v. 21.9 ± 1.1) in all days during early postpartum (Day 1 to Day 7). The number of follicles with >25 mm diameter was also greater (P < 0.05) in the early-ovulated group (1.1 ± 0.1 v. 0.1 ± 0.1) during the first 3 days postpartum. In addition, the late-ovulated mares showed greater number of follicles with 20–25 mm during Day 4 to Day 7 (2.0 ± 0.2 v. 0.7 ± 0.1). For the blood flow characteristics, no difference (P > 0.05) was detected in the coloured signals of blood flows in the follicular wall of the dominant follicle or in the ovarian pedicle ipsilateral to the largest follicle. Therefore, the characteristics of the follicle growth on the preceding days of ovulation were similar between the early- and late-ovulated mares and consistent with the follicular dynamics expected in non-pregnant and non-lactating mares. However, when the data were analysed for the days relative to parturition, a greater follicle development was present in mares that ovulate earlier during the postpartum period (<10 days). In conclusion, the results suggest that important events may occur previous to the parturition, resulting in an early follicle development, mainly in those mares that show heat signs and ovulate within 10 days postpartum. Research was supported by FAPESP process number 2010/10692-9 and CNPq process number 135954/2011-8.


1982 ◽  
Vol 92 (3) ◽  
pp. 397-403 ◽  
Author(s):  
M. B. RENFREE ◽  
G. I. WALLACE ◽  
I. R. YOUNG

The corpus luteum was removed from tammar wallabies during either lactational or seasonal quiescence, and the pouch young were replaced on the teat after lutectomy. Follicular development resumed and the animals came into oestrus 11–14 days later. Injections of oil, progesterone or androstenedione did not prevent follicular growth, although ovulation only occurred in one animal, but treatment with oestradiol-17β, either alone or mixed with progesterone, inhibited the development of follicles. These results suggest that oestrogen, of luteal origin, is responsible for the suppression of follicular development during lactational and seasonal quiescence.


2004 ◽  
Vol 4 (4) ◽  
pp. 28-31
Author(s):  
Sabaheta Hasić ◽  
Emina Kiseljaković ◽  
Radivoj Jadrić ◽  
Belma Zečević ◽  
Nešina Avdagić ◽  
...  

Long term stress exposure results in somatisation symptoms appearance. Cardiovascular, respiratory, gastrointestinal and muscle-bone symptoms arise because of intensified activity of autonomic nervous system caused by chronic stress. The aim of the study was to examine the relationship between long term war stress exposure and appearance of somatisation. 40 students of health-care faculties in Sarajevo, of both sexes, were included in investigation and divided in two groups-somatisation and control. Somatisation group subjects (N=20) lived in B&H under war conditions, from 1992-1995. Control subjects (N=20) spent the same period outside B&H. For evaluation of somatisation symptoms we used SCL-90-R test. The obtained data were statistically evaluated using Student’s t-test and χ2 test. Confidence level was set at ρ < 0,05. Our results showed statistically significant difference in somatisation level between somatisation and control subjects group. Different intensity of appearance of certain symptoms in male and female was established. The score of somatisation dimension between somatisation and control group showed statistically significant level (p < 0,0001). Study results confirmed correlation of chronic stress exposure (living in war environment) and somatisation symptom appearance. Individual organic systems had various level of symptom expression. The influence of sex on intensity of individual symptoms of somatisation is possible.


Materials ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2190
Author(s):  
Bruna Sinjari ◽  
Gianmaria D’Addazio ◽  
Manlio Santilli ◽  
Barbara D’Avanzo ◽  
Imena Rexhepi ◽  
...  

Marginal bone loss (MBL) is a key factor in long-term implant success rate. Among the different factors that influence MBL, it is the different implant shoulder designs, such as scalloped or non-scalloped, which have been widely studied on screw retained but not on cemented retained implants. Thus, the aim of the present study was to evaluate the MBL around scalloped and non-scalloped cemented retained dental implants after 4 years of loading, in humans. A total of 15 patients were enrolled in the present study. A radiographic and clinical examination was performed after implant placement (T0) and after 4 years from it (T1). The results demonstrated a differential MBL (T1-T0) of 2.436 ± 1.103 mm and 1.923 ± 1.021 mm, respectively for test (scalloped) and control (non-scalloped) groups with a statistically significant difference between them. On the other hand, no statistically significant differences were found between the groups in terms of prosthetic complication and abutment decementation, whilst ceramic crowns chipping was shown in both groups. In conclusion, the use of a scalloped platform did not provide better results on the maintenance of MBL after 4 years follow-up. In this study, this probably was determined by multiple factors, among which was the subcrestal insertion of scalloped implants.


Reproduction ◽  
2007 ◽  
Vol 133 (1) ◽  
pp. 155-163 ◽  
Author(s):  
Chiho Kawashima ◽  
Saori Fukihara ◽  
Mayumi Maeda ◽  
Etsushi Kaneko ◽  
Carlos Amaya Montoya ◽  
...  

Recent studies suggest that IGF-I is a crucial regulatory factor in follicular growth during earlypost-partumperiod. The aim of the present study was to determine in detail the changing profiles of metabolic and reproductive hormones in relation to ovulation of the dominant follicle (DF) of the first follicular wavepost-partumin high-producing dairy cows. Plasma concentrations of related hormones in 22 multiparous Holstein cows were measured from 4 weeks pre-partum to 3 weekspost-partum, and the development of DF was observed with colour Doppler ultrasound. Thirteen cows showed ovulation by 15.2 dayspost-partum. Anovulatory cows showed higher GH and lower IGF-I levels than those in ovulatory cows during the peri-partum period. Each DF developed similarly, and a clear blood flow in the follicle wall was observed despite ovulation or anovulation. In addition, detailed endocrine profiles were analyzed in 9 out of the 22 cows. Five cows showed an increase in plasma oestradiol-17β (E2) with follicular growth followed by E2 peak, LH surge and ovulation. In these cows, plasma IGF-I concentrations remained high until 10 dayspost-partumfollowed by a gradual decrease. Subsequently, the insulin level increased together with the E2 peak towards ovulation. These profiles were not observed in anovulatory cows. In conclusion, our data strongly support the concept that IGF-I and insulin represent ‘metabolic signals’ of the resumption of ovarian functionpost-partumin high-producing dairy cows. Moreover, we provide the first visual evidence that both ovulatory and anovulatory DFs of the first follicular wavepost-partumare similarly supplied with active blood flow.


2013 ◽  
Vol 25 (1) ◽  
pp. 151
Author(s):  
A. Niasari-Naslaji ◽  
V. Akbarinejad ◽  
K. Hoseinipajooh ◽  
G. Akbari ◽  
S. Gharibi ◽  
...  

The present study was conducted to evaluate laparoscopic intrauterine and intraperitoneal AI in a fat-tailed sheep breed. Multiparous and nulliparous (n = 72) healthy Shall ewes (Iranian native breed) were assigned into 3 experimental groups to be inseminated with 3 laparoscopically insemination methods, including intrauterine insemination with frozen semen (IUIFZ; n = 34), intraperitoneal insemination with fresh semen (IPIFR; n = 21), and intraperitoneal insemination with frozen semen (IPIFZ; n = 17). To perform the experiment easily and control confounding factors, the experiment was conducted in 5 replicates. In each replicate, similar numbers of ewes belonging to each experimental group were included, synchronized, and inseminated with the fresh or frozen semen collected from the same fertile ram. Estrus was synchronized using CIDR for 14 days. Immediately after CIDR removal, all ewes received 400 IU of pregnant mare serum gonadotropin. Inseminations with 300 million total spermatozoa (≥70% progressive forward motility) were performed 51.1 ± 0.64 h after CIDR removal. Intrauterine insemination was conducted at the tip of the uterine horn, ipsilateral to the ovary having a dominant follicle. In the case that both ovaries had a dominant follicle, half of the straw was deposited in each horn. In 2 other experimental groups (IPIF and IPIR) either fresh or frozen semen was deposited on the surface of ovaries having a dominant follicle. Pregnancy was diagnosed with transrectal ultrasonography on Day 30 after AI. Data were analyzed using logistic regression. The pregnancy rate in the IUIFZ group (51.7%) was significantly higher than in IPIFR and IPIFZ experimental groups (17.6 and 0%, respectively; P < 0.01), and there was significant difference between IPIFR and IPIFZ in pregnancy rate (P < 0.05). In conclusion, the laparoscopic intrauterine insemination method can be applied effectively in Shall fat-tailed sheep. Laparoscopic intraperitoneal inseminations with fresh or with frozen semen are not recommended for AI in fat-tailed sheep.


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