4 Induction of ovulation by kisspeptin in llamas

2019 ◽  
Vol 31 (1) ◽  
pp. 127 ◽  
Author(s):  
R. A. Carrasco ◽  
C. E. Leonardi ◽  
K. D. Hutt ◽  
J. Singh ◽  
G. P. Adams

After mating, female camelids ovulate in response to nerve growth factor (NGF) present in semen (formerly referred to as ovulation-inducing factor). The ovulatory effect appears to be induced by stimulation of hypothalamic gonadotropin-releasing hormone (GnRH) neuronal activity and LH secretion. Recent studies have identified kisspeptin as an important mediator of GnRH secretion in several species. In the present study, we tested the hypothesis that kisspeptin is involved in the ovulatory pathway in llamas and investigated the mechanism of this effect. In Experiment 1, ovarian function in non-pregnant, non-lactating adult female llamas was synchronized by intramuscular administration of a GnRH analogue (50µg of gonadorelin acetate; Fertiline, Vetoquinol, Quebec, QC, Canada). When a growing dominant follicle ≥8mm in diameter was detected, llamas were assigned randomly to 3 treatment groups and given an intravenous dose of purified seminal NGF (1mg, single dose; n=5), kisspeptin (0.1mg kg−1 of body weight, 2 doses 1h apart; n=5), or PBS (n=4). The bioactive 10 amino acid fragment of murine kisspeptin was used. Ovulation and corpus luteum development were assessed by transrectal ultrasonography every other day from the day of treatment (Day 0) to Day 8. In Experiment 2, ovarian function among female llamas was synchronized, as in Experiment 1. When a growing dominant follicle ≥8mm in diameter was detected, llamas were given kisspeptin (0.1mg kg−1 of body weight IV, 2 doses 1h apart) beginning 2h after pretreatment with either a GnRH receptor blocker (cetrorelix acetate, 1.5mg per llama IV; Sigma, Oakville, ON, Canada; n=6) or saline (n=6). Llamas were examined 48h later by transrectal ultrasonography to detect ovulation and 8 days later to determine the presence of a corpus luteum. Chi-square tests were used to compare ovulation rates, and ANOVA for repeated measures was used to compare diameter profiles of the corpus luteum. In Experiment 1, ovulation rate did not differ between the NGF and kisspeptin groups (5/5 in each; 100%) and was greater than in the control group (0/4; 0% P<0.05). Corpus luteum diameter did not differ between llamas that ovulated in response to treatment with NGF or kisspeptin (13.2±0.8 and 14.0±1.2mm on Day 8, respectively). In Experiment 2, none of the llamas pretreated with cetrorelix ovulated in response to kisspeptin treatment (0/6; 0%), whereas all of the llamas pretreated with saline ovulated in response to kisspeptin treatment and had a corpus luteum at Day 8 (6/6; 100%; P<0.05). Results supported the hypothesis that kisspeptin induces ovulation in llamas. Because a GnRH receptor antagonist blocked ovulation, our interpretation is that the site of action of kisspeptin is upstream of the pituitary gland and involves control of GnRH release from the hypothalamus. These findings raise the possibility that kisspeptin mediates the ovulation-inducing effect of NGF. Research was supported by the Natural Sciences and Engineering Research Council of Canada.

PLoS ONE ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. e0245553
Author(s):  
João C. Alves ◽  
Ana Santos ◽  
Patrícia Jorge ◽  
Catarina Lavrador ◽  
L. Miguel Carreira

Objective To evaluate the effect of an intra-articular (IA) administration of triamcinolone hexacetonide, compared with saline. Patients and methods Forty (N = 40) hip joints were randomly assigned to a treatment group (THG, n = 20, receiving IA triamcinolone hexacetonide) and a control group (CG, n = 20, receiving IA saline). On treatment day (T0), and at 8, 15, 30, 90 and 180 days post-treatment, weight distribution, joint range of motion, thigh girth, digital thermography, radiographic signs, synovial fluid interleukin-1 and C-reactive protein levels were evaluated. Data from four Clinical Metrology Instruments was also gathered. Results were compared Repeated Measures ANOVA, with a Huynh-Feldt correction, Paired Samples T-Test or Wilcoxon Signed Ranks Test. A Kaplan-Meier test was performed to compare both groups, with p<0.05. Results Joints were graded as mild (65%), moderate (20%) and severe (15%). Patients of both sexes, with a mean age of 6.5±2.4 years and bodyweight of 26.7±5.2kg, were included. No differences were found between groups at T0. Comparing THG to CG, weight distribution showed significant improvements in THG from 8 (p = 0.05) up to 90 days (p = 0.01). THG showed lower values during thermographic evaluation in the Lt view (p<0.01). Pain and function scores also improved from 30 to 180 days. Increasing body weight, age, and presence of caudolateral curvilinear osteophyte corresponded to worse response to treatment. Results of the Kaplan Meier test showed significant differences between groups, with THG performing better considering several evaluations and scores. Conclusion THG recorded significant improvements in weight-bearing and in with the considered CMIs, particularly pain scores. Lower thermographic values were registered in THG up to the last evaluation day. Age, sex, and radiographic findings did significantly influenced response to treatment.


2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 377-377
Author(s):  
Giovanni M Baez ◽  
Wilfran E Rivera

Abstract Tropical cow-calf operations using Bos indicus crossbreds are characterized by extended periods of time before the establishment of ovarian cyclicity. The aim was to determine whether the increase of progesterone concentrations during postpartum anestrous using intravaginal devices along with injection of estradiol benzoate would advance the occurrence of first ovulation after calving. 269 suckled crossbred cows kept in different farms at North-Santander (Colombia) were randomized in one of the following treatments: 1:Control (n = 88) no further treatment; 2:P4 (n = 91) cows received an intravaginal device containing 0.588 g of progesterone during 7 days at day 50±3 after calving; 3:P4+E2 (n = 90) as treatment 2 plus an additional injection of 2.0 mg of estradiol benzoate at the time of device insertion. Ovarian ultrasound was performed weekly starting on the day of treatments until ovulation (disappearance of a dominant follicle with later appearance of a corpus luteum within two consecutive examinations). Calving-Ovulation Interval was recorded and means between groups were analyzed using ANOVA (α=0.05). For the control group, COI tended (P = 0.08) to be longer for primiparous cows (149.6±4.5 days, n = 14) compared to multiparous cows (140.4±2.1d, n = 74). Treatment with P4 reduced the COI for both primiparous (105.3±5.4d, n = 15; P &lt; 0.0001) and multiparous (96.4±3.0d, n = 76; P &lt; 0.0001) compared to the controls (P = 0.21 between groups of age). When primiparous cows were treated with P4+E2 the COI decreased compared to both P4 and control treatments (82.3±2.8d, n = 17; P &lt; 0.0001). However, in multiparous cows there was no effect of P4+E2 compared to P4 treatment (94.6±2.6d, n = 73; P = 0.65), then COI was shorter for primiparous compared to multiparous cows (P = 0.03) with P4+E2 treatment. The use of an intravaginal device containing progesterone advances the time of first ovulation after calving in suckled cows. Additional use of estradiol benzoate reduces the time for first ovulation in primiparous but not multiparous cows.


2017 ◽  
Vol 34 (03) ◽  
pp. 173-177
Author(s):  
A. Oyewopo ◽  
K. Obasi ◽  
K. Anumudu ◽  
E. Yawson

Abstract Introduction: Calabash chalk is a naturally occurring mineral, chiefly composed of fossilized sea shells. It is prepared from clay and mud mixed with other ingredients, including lead, arsenic, sand and wood ash. Clay consumption is correlated with pregnancy, and also to eliminate morning sickness in women. The aim of this study is to evaluate the effects of calabash chalk on the ovarian function in adult female Wistar rats. Methods: Eighteen (18) adult female Wistar rats. Group A served as the control group, group B received 40 mg/kg body weight of Non-salted calabash chalk while group C received 40 mg/kg body weight of Salted calabash chalk for 14 days. On day 15, the animals were sacrificed for histological and biochemical examination. Results: Results showed a significant (P< 0.05) reduction in follicle stimulating hormone (FSH) levels of the treatment groups when compared with the control group and an increase in luteinizing hormone (LH) levels of the treatment groups when compared with the control group. Histological examination of the ovaries showed severe deterioration of the ovarian follicles, necrosis and follicular atresia. Conclusion: Calabash chalk is toxic to ovarian function. These alterations have been shown to be the leading cause ofinfertility in female rats. Hence, proper monitoring, education, and regulation of the product is needed.


2021 ◽  
Vol 14 (1) ◽  
pp. 87-92
Author(s):  
Mina Alipoor ◽  
◽  
Marzeyeh Loripoor ◽  
Majid Kazemi ◽  
Farshid Farahbakhsh ◽  
...  

Postpartum depression is a common disabling psychosocial disorder that could have adverse effects on the life of the mother, infant, and family. The present study was conducted to evaluate the effect of ketamine on preventing postpartum depression in women undergoing caesarian sections considering the relatively known positive effect of ketamine on major depression. The present double-blind, randomized clinical trial was conducted on 134 women undergoing scheduled caesarian sections. Participants were randomly allocated into two groups of control and intervention. To induce anesthesia, 1–2 mg/kg of body weight of Nesdonal and 0.5 mg/kg of body weight of ketamine were used in the intervention group, while only 3–5 mg/kg of body weight Nesdonal was administered in the control group. Data were gathered using the Edinburgh Postnatal Depression Scale (EPDS) in three stages: before the caesarian section and two and four weeks after the caesarian section. Data were analyzed using variance analysis with repeated measures and the Chi-square test. Results of the present study showed that the mean (± standard deviation) of the depression score in the intervention and control groups were 13.78±3.87 and 13.79±4.78(p = 0.98) before the caesarian section, 11.82±3.41 and 14.34±4.29 (p < 0.001) two weeks after and 10.84±3.48 and 13.09±3.79 (p = 0.001) four weeks after the caesarian section, respectively. Using ketamine in the induction of general anesthesia could be effective in preventing postpartum depression. However, further studies are required to strengthen these findings.


Author(s):  
Ercan Soydan ◽  
Uğur Şen

The aim of this study was to determine the effect of gonadotropin-releasing hormone (GnRH) administration on the estrus rate and ovarian activity in Karayaka sheep. In the present study 20 Karayaka sheep breed, which gave at least 2 births and had similar body weight, were used as animal material. At the beginning of the study, 1 ml PGF2α was intramuscularly injected to all ewes in order to lutalyse the corpus luteum (CL) on the ovary. After 9 days of PGF2α administration, sheep were randomly divided into two equal groups; intra-vaginal sponge containing 40 mg flugestone acetate was inserted into vagina of the ewes in first group (n=10) and the ewes in the second group (n=10) were used as controls. Sponges were removed after 14 days and intramuscular injection of 1 ml PGF2α was performed. After 36 hours, intramuscular injection of 1 ml GnRH was performed and all ewes were introduced to Karayaka rams and ewes in estrus were recorded during 72 hours. At the end of estrus determination period all ewes were slaughtered and number of small (1-3 mm), large (> 3 mm) and total follicles and CL were determined on both ovaries. GnRH administered ewes showed higher (100%) estrus rate than the ewes (%70) in the control group. GnRH administered ewes had higher number of small and total follicles, and CL than those of ewes in control group. However, there was no significant difference between experimental groups in terms of large follicle numbers. As a result, it was concluded that the GnRH administration after vaginal sponge application in the Karayaka ewes during the breeding season increased estrus rate and stimulated ovarium activity.


2012 ◽  
Vol 24 (1) ◽  
pp. 113 ◽  
Author(s):  
J. Yapura ◽  
J. Singh ◽  
R. J. Mapletoft ◽  
R. Pierson ◽  
D. Rogan ◽  
...  

Letrozole, a non-steroidal aromatase inhibitor, prevents the body from producing its own oestrogen. The potential use of this compound for herd synchronization is supported by previous studies in which letrozole treatment increased mean plasma LH concentrations, prolonged the period of dominance of the extant dominant follicle and delayed emergence of the next follicular wave. Heifers given a 3-day regimen of letrozole exhibited greater corpus luteum diameter indicative of a luteotrophic effect. The objective of the present study was to test the hypothesis that letrozole treatment during the development of the preovulatory follicular wave will delay ovulation. Post-pubertal beef heifers were given 2 luteolytic doses of PGF (12 h apart) and monitored by ultrasonography for ovulation. Ovarian follicular wave emergence was synchronized by ultrasound-guided transvaginal follicular ablation 5 to 8 days after PGF-induced ovulation (Day –1 = follicular ablation, Day 0 = wave emergence) and a luteolytic dose of PGF was given 60 and 72 h later. On Day 1, heifers were divided randomly into 2 groups (n = 15/group) and given an intravaginal device containing 1 g of letrozole or a blank device (control). The intravaginal devices were removed on Day 7, or at the time of ovulation, whichever occurred first. The ovaries were monitored by ultrasonography and a blood sample was collected daily from day of ablation to 12 days post-ovulation. Single point measurements were analysed by t-tests and serial data were analysed by analysis of variance for repeated measures. Multiple contrasts were made by Tukey's test. The interval from placement of the intravaginal device to ovulation was longer in letrozole-treated animals (6.1 ± 0.25 vs 5.1 ± 0.26 days, P < 0.01). Compared with controls, the day-to-day diameter profile of the dominant follicle of the ovulatory wave was larger (P < 0.05) and the maximum diameter greater (14.6 ± 0.51 vs 12.4 ± 0.53 mm; P < 0.01) in letrozole-treated heifers. The diameter profile of the corpus luteum formed post-letrozole treatment did not differ between groups; however, plasma P4 concentrations were higher (P < 0.01) in heifers treated with letrozole. In summary, a slow-release intravaginal letrozole device delayed ovulation by 24 h and induced the formation of a corpus luteum that secreted higher levels of progesterone. A slow-release intravaginal letrozole device may become useful for the development of an aromatase inhibitor-based protocol to control ovulation for herd synchronization and to enhance fertility by increasing circulating progesterone concentrations during the first 7 days post-AI or embryo transfer in cattle. Supported by the Natural Sciences and Engineering Research Council of Canada and Bioniche Life Sciences Inc.


2000 ◽  
Vol 166 (2) ◽  
pp. 355-361
Author(s):  
E Ogawa ◽  
BH Breier ◽  
I Fujiwara ◽  
K Iinuma

Sexual dimorphism of somatic growth in rats appears to reflect differing actions of sex steroids. However, mechanisms of gonadal steroid effects on the somatotropic axis are incompletely understood. To evaluate whether GH is involved in the effects of long-term gonadal suppression on somatic growth in rats, a GnRH agonistic analogue (GnRHa) was administered to normal Sprague-Dawley rats (controls) and to a strain of rats with complete growth hormone deficiency (GHD; n=4-6 in each group). Subcutaneous injection of GnRHa (2 mg/kg) or saline were given within 48 h after birth and repeated every 3 weeks. GnRHa treatment significantly reduced serum gonadal steroid levels in rats of both sexes with small testes in males and impaired development of internal genitalia in females. GnRHa-treated control females became significantly heavier (P<0.01 ANOVA for repeated measures) than saline-treated rats beginning at 8 weeks. However, female GHD rats with GnRHa treatment did not differ in body weight from rats receiving saline. In male rats, GnRHa treatment did not change body weight in either control or GHD rats. Serum IGF-I concentrations did not differ between treatment groups in GHD and control rats of either sex. Hepatic GH binding was reduced significantly by GnRHa treatment in female control rats (P<0.01), but not in female GHD rats. These data suggest that sexual dimorphism in body size and its modulation by estrogens are independent of circulating IGF-I levels suggesting non-endocrine IGF-I-mediated mechanisms, and that GH-induced somatic growth is modulated by estrogens, but not androgens, in rats.


2021 ◽  
pp. 036354652098155
Author(s):  
João Carlos Agostinho Alves ◽  
Ana Margarida Moniz Pereira dos Santos ◽  
Patrícia Isabel Figueiredo Jorge ◽  
Catarina Falcão Trigoso Vieira Branco Lavrador ◽  
Luis Miguel Alves Carreira

Background: Osteoarthritis (OA) represents a significant burden to societies, as it affects quality of life and performance and implies a large cost in terms of health care. Autologous platelets are a regenerative treatment modality for OA that are thought to be a potential stimulation of the natural healing cascade. Purpose: To describe the effect of the platelet concentrate V-PET in the management of OA in a naturally occurring canine model, using several outcome assessment modalities. Study Design: Controlled laboratory study. Methods: A total of 40 joints of active working police dogs with hip OA were randomly assigned to a control group (CG) and a platelet concentrate group (PCG; treatment) and evaluated. At treatment day (T0) and 8, 15, 30, 90, and 180 days after treatment, weight distribution, joint range of motion at flexion and extension, thigh girth, digital thermography, radiographic signs, 4 clinical metrology instruments, and synovial fluid interleukin 1 and C-reactive protein levels were recorded. Results were compared using repeated-measures analysis of variance with a Huynh-Feldt correction, paired-samples t test, or Wilcoxon signed rank test, with P < .05. Results: Dogs were 6.5 ± 2.4 years old (mean ± SD) and had a body weight of 26.7 ± 5.2 kg. At T0, 32 (80%) joints were graded as having mild OA, 6 (15%) as moderate, and 2 (5%) as severe. No differences were found between groups at T0. Between the PCG and CG, the symmetry index showed significant improvements in the PCG from 8 days ( P = .01) to 180 days ( P = .01). Joint flexion also improved in the PCG up to 90 days ( P < .05) and extension improved up to 180 days ( P < .01). Several clinical metrology instrument scores also improved up to 90 to 180 days after treatment. In the CG, radiographic signs progressed, while the PCG showed some improved signs. In both groups, increasing body weight and age corresponded with worse clinical and laboratory findings. Conclusion: A single injection of platelet concentrate had a positive effect, lasting up to 6 months, on several clinical, imaging, and laboratory signs in a naturally occurring canine OA model. Clinical Relevance: We characterized the effects of this platelet concentrate in dogs, considered the gold standard of the study of OA, with a group of working animals with similar high demands as athletes.


2019 ◽  
Vol 41 (336) ◽  
pp. 22-25
Author(s):  
Akshay Sharma ◽  
Madhumeet Singh ◽  
Pravesh Kumar ◽  
Pradeep Kumar Dogra

Abstract The present study envisages the effect of PGF2α and antibiotic treatment on ovarian cyclic activity and regression of corpus luteum verum in post-partum dairy cows. Cows were divided into three treatment (PG8, PG25, antibiotic) and a control group. Ovarian activity was studied by examining follicular dynamics upto 42 days post-partum in which diameter of dominant follicle before first ovulation, the number of days to first ovulation and complete regression of corpus luteum verum were evaluated. Body condition score was recorded for all the cows in different groups. Also, ovulation on ovary ipsilateral or contralateral to previous gravid uterine horn was noted. On transrectal ultrasonography at a 3-day interval, dominant follicle diameter prior to ovulation was significantly higher (p<0.01) in PG8 group. The mean time required for complete regression of CL verum was not significantly (p>0.05) lower in PG8 group i.e. 24.33±1.48 days in comparison to PG25, antibiotic and control group (26.67±1.48, 29.00±1.81and 27.60±1.40 days post-partum, respectively). A subsequent ovarian activity was affected as 70.83 and 66.33% Ist and IInd ovulations occurred on the ovary contralateral to corpus luteum verum. In conclusion, contralateral ovary was more active in terms of ovulation whereas presence of corpus luteum verum had no effect on post-partum ovarian cyclic activity.


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