scholarly journals Interval between Removal of a 4.7 mg Deslorelin Implant after a 3-, 6-, and 9-Month Treatment and Restoration of Testicular Function in Tomcats

Animals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1559 ◽  
Author(s):  
Lluis Ferré-Dolcet ◽  
Lisa Carniello ◽  
Silvia Ferro ◽  
Andrea Cattai ◽  
Stefano Romagnoli ◽  
...  

Deslorelin implants have been used to produce a reversible sterilization in several species. In cats, the prolonged duration (12–15 months in tomcats and 18–22 months in queen) is often too much for cat breeders who request early implant removal. The interval between implant removal and resumption of reproductive function in cats has never been investigated. Eighteen tomcats received a 4.7 mg deslorelin implant placed in the periumbilical area and surgically removed during all seasons of the year after 3, 6, or 9 months (n = 6, 6, and 6 cats, respectively). Following implant removal, all cats received a clinical exam every two weeks, including testicular ultrasonographic measurement, observation of penile spikes, and blood collection for serum testosterone assay. Restoration of serum testosterone secretion occurred after 23 ± 6, 23 ± 6, and 22 ± 7 days in the 3-, 6-, and 9-month groups, respectively. Restoration of testicular function was confirmed by histology in 13/15 cats undergoing orchiectomy at the end of the study while the owners of the remaining two cats opted to maintain their animals intact. Removal of a 4.7 mg deslorelin implant after 3, 6, or 9 months is followed by resumption of serum testosterone secretion after about 3 weeks independent of age or season.

2021 ◽  
Author(s):  
Lluis Ferré Dolcet ◽  
Silvia Ferro ◽  
Barbara Contiero ◽  
Christelle Fontaine ◽  
Tamara Badon ◽  
...  

Abstract Objective: The use of deslorelin implantsto control reproduction in cats is increasing but because of its prolonged duration, cat breeders oftenrequest implant removal before the end of the treatment. Assaying Anti Mullerian Hormone (AMH) concentrations might be useful to predict time of resumption of ovarian activity in deslorelin-treated queens following implant removal. In queens a minimum of 3 weeks during increasing photoperiod after implant removal has been described for resumption of ovarian activity but no information about AMH concentrations were observed for determining ovarian activity.Animals: Sixteen queens in whichdeslorelinimplants were surgically removed after3, 6 or 9 months (n= 6, 4 and 6 queens, respectively) were used in this study. Procedures: A general and reproductive health check with a GnRH stimulation test were performed before the treatment.After implant removal queens were checked every 1-2 weeks withreproductive ultrasonography, a vaginal smear and blood collection to assay AMHconcentrations. Results: AMH concentrations decreased significantly during treatment to < 2.5+0.6 ng/ml (p<0.05) and reached a nadir at 1.9+0.9 (p<0.05) one-week post-removal.Following implant removal AMH concentrations started to rise reaching a value of 4.3+1.2 ng/ml on the third week and were not different from pre-treatment levels on week 6 post-removal (5.8 ng/ml +0.9, p>0.05).AMH values did not differ depending on duration of deslorelin treatment but were lower in adult queens (p<0.05).Clinical relevance: AMH assay can be a useful tool to follow resumption of feline ovarian function following a deslorelin treatment.


1999 ◽  
Vol 161 (2) ◽  
pp. 211-218 ◽  
Author(s):  
M Tena-Sempere ◽  
L Pinilla ◽  
LC Gonzalez ◽  
C Dieguez ◽  
FF Casanueva ◽  
...  

Leptin, the product of the ob gene, has emerged recently as a pivotal signal in the regulation of fertility. Although the actions of leptin in the control of reproductive function are thought to be exerted mainly at the hypothalamic level, the potential direct effects of leptin at the pituitary and gonadal level have been poorly characterised. In the present study, we first assessed the ability of leptin to regulate testicular testosterone secretion in vitro. Secondly, we aimed to evaluate whether leptin can modulate basal gonadotrophin and prolactin (PRL) release by incubated hemi-pituitaries from fasted male rats. To attain the first goal, testicular slices from prepubertal and adult rats were incubated with increasing concentrations (10(-9)-10(-7) M) of recombinant leptin. Assuming that in vitro testicular responsiveness to leptin may be dependent on the background leptin levels, testicular tissue from both food-deprived and normally-fed animals was used. Furthermore, leptin modulation of stimulated testosterone secretion was evaluated by incubation of testicular samples with different doses of leptin in the presence of 10 IU human chorionic gonadotrophin (hCG). In addition, analysis of leptin actions on pituitary function was carried out using hemi-pituitaries from fasted adult male rats incubated in the presence of increasing concentrations (10(-9)-10(-7) M) of recombinant leptin. Serum testosterone levels, and basal and hCG-stimulated testosterone secretion by incubated testicular tissue were significantly decreased by fasting in prepubertal and adult male rats. However, a significant reduction in circulating LH levels was only evident in adult fasted rats. Doses of 10(-9)-10(-7) M leptin had no effect on basal or hCG-stimulated testosterone secretion by testes from prepubertal rats, regardless of the nutritional state of the donor animal. In contrast, leptin significantly decreased basal and hCG-induced testosterone secretion by testes from fasted and fed adult rats. In addition, 10(-9) M leptin inhibited LH and FSH secretion by incubated hemi-pituitaries from fasted adult males, whereas, at all doses tested, it was ineffective in modulating PRL release. Our results show that leptin, depending on the state of sexual maturation, is able to inhibit testosterone secretion acting at the testicular level. Furthermore, the present data suggest that the actions of leptin on the reproductive system are complex and are probably carried out at different levels of the hypothalamic-pituitary-gonadal axis.


1979 ◽  
Vol 91 (1) ◽  
pp. 184-192
Author(s):  
Evangelina Valdés ◽  
Carlos Fernández del Castillo ◽  
Raul Gutiérrez ◽  
Fernando Larrea ◽  
Martha Medina ◽  
...  

ABSTRACT A 12-year old, 46 XX true hermaphrodite born with genital ambiguity was studied and successfully treated. The serum LH and FSH profile resembled that of a pubertal normal individual, and LH-RH administration induced a normal LH response. Baseline testosterone serum levels were within the range for normal children. Exogenous HCG stimulation induced a significant serum testosterone increase up to values similar to those observed in normal post-pubertal males. Surgical examination disclosed the presence of bilateral ovotestis, normal Mullerian derivatives, epididymis, and vas deferens. A complete ovotestis with testicular predominance and the testicular portion of the contralateral ovotestis as well as the Wolffian derivatives, were removed. A further HCG stimulation 3 months after surgery, failed to induce serum testosterone increase. Spontaneous menarche was observed 6 months after surgery and ovulation was well documented. At present the patient has several characteristics of female sex including those of chromosome complement, gonad, internal and external genitalia, hormone levels and gender identity, thus demonstrating that treatment was successful and that reproductive function could be obtained. The finding of spontaneous ovulation following removal of the testicular portion suggests normal cyclic gonadotrophic release implying a difference between animal models and man in regard to hypothalamic virilization.


1989 ◽  
Vol 120 (2) ◽  
pp. 180-186 ◽  
Author(s):  
Lee M. Sanford

Abstract. The testes of the ram become more responsive to LH stimulation following immunoneutralization of endogenous estradiol. The possibility that testosterone secretion is facilitated by increased LH-binding activity in the testes was investigated in the present study conducted with adult Dorset × Leicester × Suffolk rams during the time of testicular recrudescence. Patterns of episodic LH release and testosterone secretion (days –5, 10 and 24) and LH-binding activity in testicular biopsy samples (days –1, 14 and 28) were assessed on the days indicated relative to the onset of passive immunization and the establishment of relatively low titres (~1:200) of estradiol antiserum. During the experimental period, mean serum testosterone concentration increased by approximately 150% for the immunized rams as basal concentration and pulse amplitude increased, while all characteristics of testosterone secretion remained unchanged for the nonimmunized rams. Characteristics of LH release and the concentration of LH-binding sites in the testes, however, were always similar for both groups of rams. Further, group differences in FSH and PRL secretion and in the concentration of testicular FSH-binding sites did not occur. These results provide evidence for an estradiol direct (gonadotropin independent) negativefeedback component in the regulation of Leydig cell function in the ram.


1986 ◽  
Vol 109 (2) ◽  
pp. R9-R11 ◽  
Author(s):  
W. v. Rechenberg ◽  
J. Sandow ◽  
P. Klatt

ABSTRACT Continuous administration of LH-releasing hormone (LHRH) agonists is an effective method of suppressing testosterone secretion in the male. The effect of the LH-releasing hormone (LHRH) agonist, buserelin, administered to bulls by constant infusion from osmotic minipumps was studied. In one experiment with four treated and one control bull, 109 pg buserelin/day were administered for 22 days. Immediately after implantation, serum testosterone concentrations rose from below 35 nmol/l to 35-105 nmol/l, and all four buserelin-infused bulls showed increased testosterone secretion during the treatment period. After removal of the minipumps, testosterone concentrations decreased to pretreatment levels. In a second experiment bulls were infused for 42 days (four treated and one control), and identical results were obtained. Testosterone secretion was stimulated (52-87 nmol/l serum) during the entire treatment period. These results demonstrate that conditions for stimulation of the pituitary-testicular axis may vary between species. Infusion of low doses of LHRH-agonists in bulls has an extended stimulatory effect without immediate desensitization of gonadotrophin release.


2012 ◽  
Vol 24 (7) ◽  
pp. 999 ◽  
Author(s):  
T. Keeley ◽  
P. D. McGreevy ◽  
J. K. O'Brien

Devil facial tumour disease (DFTD) is the cause of the rapid decline of wild Tasmanian devils. Female devils are seasonal breeders with births peaking during autumn (i.e. March) but the degree of reproductive seasonality in male devils is unknown. The objective of this study was to examine the potential effects of season and DFTD on reproductive function in male devils (n = 55). Testicular (1.90 ± 0.23 g) and epididymal (0.90 ± 0.06 g) weights were maximal during autumn and spring (P < 0.05), whereas prostate (3.71 ± 0.74 g) and Cowper’s gland (0.68 ± 0.22; 0.52 ± 0.21 g) weights peaked during autumn (P < 0.001). The motility of spermatozoa from the cauda epididymides extracted post-mortem was similar (P > 0.05) across season and disease state (31.5 ± 13.1% total motility). Testicular and epididymal weights were no different between animals displaying late or early-stage DTFD signs or disease-free animals (P > 0.1). The accessory sex glands were larger in late-stage DFTD animals than in animals with early-stage disease signs or which were disease-free (P < 0.01) but effects of season on this result can’t be excluded. Serum testosterone concentrations peaked during summer (0.25 ± 0.18 ng mL–1) but values were not different from the preceding and subsequent seasons (P > 0.05), nor influenced by disease stage (P > 0.1). Seasonal and DFTD-related changes in serum cortisol concentrations were not evident (P > 0.1). Male devil reproduction does not appear to be restricted by season nor inhibited by DFTD.


1999 ◽  
Vol 276 (6) ◽  
pp. E1099-E1104 ◽  
Author(s):  
William A. Banks ◽  
Robert N. McLay ◽  
Abba J. Kastin ◽  
Ulla Sarmiento ◽  
Sheila Scully

Leptin is a 17-kDa protein, secreted by fat, that controls adiposity and has been proposed to have numerous effects on reproduction in the mouse. To assess whether the effects of leptin on testicular function are direct, we determined whether leptin can cross the murine blood-testis barrier. Multiple time regression analysis showed that a small amount of blood-borne leptin is able to enter the testis but does so by a nonsaturable process. In addition, no significant expression of leptin receptors was found at the Leydig cells or Sertoli cells of the testis. This compares with the presence of a saturable transport system for leptin at the blood-brain barrier and abundant receptors for leptin at the leptomeninges, neurons, and choroid plexus of the central nervous system (CNS). These results support the hypothesis that the effects of leptin on reproductive function are not mediated at the level of the testis but indirectly, probably through the CNS.


2020 ◽  
Vol 105 (5) ◽  
pp. 1608-1616
Author(s):  
Angela K Lucas-Herald ◽  
Andreas Kyriakou ◽  
Malika Alimussina ◽  
Guilherme Guaragna-Filho ◽  
Louise A Diver ◽  
...  

Abstract Introduction The relationship between serum anti-Müllerian hormone (AMH) and the testosterone response to human chorionic gonadotropin (hCG) stimulation test is unclear. Methods Children who had hCG stimulation tests in one tertiary centre from 2001 to 2018 were included (n = 138). Serum testosterone was measured before (day 1 [D1]) and after 3 days (D4) of hCG stimulation. Sixty-one of these children also had prolonged hCG stimulation for 2 more weeks and serum testosterone measured after 21 days (D22). All children had a serum AMH measured on D1. Results Of the 138 children, D4 testosterone was normal in 104 (75%). AMH was low in 24/138 (17%) children, and 16 (67%) of these had a low D4 testosterone. Median AMH in those who had a normal vs low D4 testosterone was 850 pmol/L (24, 2280) and 54 pmol/L (0.4, 1664), respectively (P &lt; 0.0001). An AMH &gt; 5th centile was associated with a low D4 testosterone in 18/118 (13%; P &lt; 0.0001). Of the 61 children who had prolonged hCG stimulation, D22 testosterone was normal in 39 (64%). AMH was low in 10/61(16%) children and 9 (90%) of these had a low D22 testosterone. Median AMH in children who responded and did not respond by D22 was 639 pmol/L (107, 2280) and 261 pmol/L (15, 1034) (P &lt; 0.0001). Conclusion A normal AMH may provide valuable information on overall testicular function. However, a low AMH does not necessarily predict a suboptimal testosterone response to hCG stimulation.


1979 ◽  
Vol 11 (S6) ◽  
pp. 5-18 ◽  
Author(s):  
A. Vermeulen

The menopause clearly marks the end of the reproductive phase in the female, but no comparable event of sudden discontinuity in fertility occurs in the male. Successful paternity in man has been recorded at the age of 94 (Seymour, Duffy & Koerner, 1935). This difference between the sexes is rather surprising, as the male does not seem to age in a fundamentally different way from the female and as, moreover, the death rate for males is higher in all age groups, than for females. This may be related to the presence of only one X chromosome, the eventual defects of which cannot be compensated for by the activity of the homologue. The Y chromosome does not appear to bear vital genes, as it is not essential for life, XO individuals being perfectly viable, in distinction to the YO genotype. Moreover in the absence of male inducers, the phenotype is female, suggesting that the male phenotype is a more complex differentiation. For whatever reason, the lower viability of the male remains a striking fact: males represent only 35% of the age group over 75 years. The persistence of reproductive function into old age is therefore the more surprising. This does not mean, however, that a gradual decrease in sexual activity and testicular function in the ageing male does not occur. From adolescence onwards, there is a continuous decline in sexual interest, arousal and activity, without a sudden discontinuity in any age group.


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