Serum antimüllerian hormone concentrations in female cats. Relation with ovarian remnant syndrome, ovarian cysts and gonadectomy status.

The aim of this study was to reveal (1) the determination of the serum antimüllerian hormone concentrations in cats with ovarian remnant syndrome and ovarian cyst, (2) the effectiveness of the serum antimüllerian hormone concentrations in detecting gonadectomy status, and (3) ovarian expression of the antimüllerian hormone in the ovarian cysts and ovarian remnant tissue. For this purpose, a total of 31 domestic cats older than 1 year, including ORS (n = 9), OC (n = 3), spayed (n = 8), and intact (n = 11), were used in the study. Serum and intrafollicular AMH concentrations were determined by the electrochemiluminescence immunoassay, and expression of the AMH was determined by the immunohistochemical method. The serum AMH concentration in the ORS group was 1.49 ± 1.24 ng/ml (0.10-3.63 ng/ml) whereas it was 1.78 ± 0.92 ng/ml (0.8-2.63 ng/ml) in the OC group. AMH concentration in the intrafollicular fluid was determined as 0.023 ng/ml in a cat with an ovarian cyst. While the serum AMH concentration was below 0.01 ng/ml in spayed cats, it was 5.80 ± 3.30 ng/ml (1.88-11.86 ng/ml) in the intact cats. There was a significant difference between the spayed and intact groups in terms of serum AMH concentration (p < 0.05). Moreover, in cats with ovarian cyst and ovarian remnant syndrome, no difference was found between the groups in terms of serum AMH concentration (p > 0.05). No difference was found between the ovarian remnant syndrome and intact cats in terms of serum AMH concentration (p > 0.05). In immunohistochemical staining, ovarian cysts were found to be negative for AMH while a moderate (+2) AMH positivity was observed in other follicles. Furthermore, in cats with ovarian remnant syndrome, severe (+3) AMH positivity was observed. As a result, it was determined that gonadectomy status can be accurately diagnosed by the AMH measurement. Ovarian remnant syndrome cannot be diagnosed accurately by AMH measurement. In addition, it was found that AMH did not seem to play a role in the pathogenesis of ovarian cysts in cats.

The effect of Gonadotropin releasing hormone administration on fertility and embryonic loss in goats during the anoestrus period

Following the induction of oestrus out of season in small ruminants, low fertility and variations in fertility rates are associated with embryonic losses. One of the main causes of embryonic loss is luteal dysfunction. Gonadotropin Releasing Hormone (GnRH) supports the luteal structure, and increasing progesterone levels may be beneficial in terms of promoting embryonic life. The main objective of the present study was to evaluate the efficacy of GnRH administration following an oestrus induction protocol in the anoestrus season for preventing embryonic loss in goats having failure to conceive during the season. In the study, 106 Damascus goats aged 3-5 years and weighing 45-60 kg were used. The oestrus of 106 goats in the anoestrous group was stimulated with progesterone and pregnant mare serum gonadotropin (PMSG) treatment. Out of breeding season, goats were divided into the 4 following groups: GnRH0 (n = 27), GnRH7 (n = 26), GnRH0+7 (n = 27) and control (n = 26). In each goat, an intravaginal sponge (IS) containing 20 mg of fluorogestone acetate (FGA) was placed into the vagina and left for 9 days. With the withdrawal of the sponge, 550IU PMSG and 125 µg of d-cloprostenol were injected intramuscularly. Oestrus detection was made via teaser bucks for 3 days starting 24 h after withdrawal of the IS. Eighteen bucks known to be fertile were used for breeding. Goats in the oestrus period were mated via natural breeding. The GnRH analogue lecirelin was injected intramuscularly at breeding in the GnRH0 group, on day 7 post-breeding in the GnRH7 group, and both at breeding and on day 7 post-breeding in the GnRH0+7 group. No injections were given to the control group. Blood samples for progesterone measurement were taken by jugular vena puncturing on days 3, 6, 7, 10, 13, 16, and 19 after breeding from 10 randomly chosen goats in all groups. The goats with a level of > 3.5 ng/mL of progesterone on day 21 post-breeding were evaluated as pregnant. Pregnancy was also viewed on day 50 after breeding by real-time ultrasonography (USG) with a 5-7.5 MHz convex probe. The oestrus rate was 96.23% (102/106) in the goats. The rates of onset of oestrus between 36-48 h, 48-60 h and 60 h and beyond were 38.7% (41/106), 21.7% (23/106) and 35.8% (38/106), respectively. The total pregnancy rate was 35.8% (38/106). There were no statistically significant differences (P > 0.05) found for the pregnancy rate, embryonic death rate or progesterone concentration of the groups. However, serum progesterone levels were statistically different in the GnRH7 group compared with the control group (P < 0.05). After synchronisation, various anti-luteolytic strategies can be used to support corpus luteum development and elevate progesterone concentration in the luteal phase to decrease embryonic loss and increase reproductive performance. Therefore, application of GnRH to support the luteal structure and to increase progesterone levels may be beneficial in terms of supporting embryonic life. The results showed that GnRH treatment on the day 7 post-breeding following oestrus induction, including FGA and PMSG, can increase serum progesterone levels in Damascus goats in the anoestrus period. However, following oestrus induction in the anoestrus period, it was seen that GnRH treatment at breeding or on day 7 after breeding did not have any positive effect on embryonic loss or reproductive performance. In conclusion, it was considered that this protocol could be implemented successfully, yielding a 35% pregnancy rate in Damascus goats in the anoestrus period, but embryonic loss must be deeply studied in detail.(AU)

Theranekron for treatment of endometriosis in a rat model compared with medroxyprogesterone acetate and leuprolide acetate.

OBJECTIVES: The aim of this study was to compare the effects of theranekron, medroxyprogesterone acetate (MPA), and leuprolide acetate (LA) on surgically induced endometriosis in a rat model. STUDY DESIGN: Endometriosis was surgically induced in forty female rats during estrus. After 3 weeks, a second operation was performed and the rats were randomized using a randomization table into theranekron, MPA, LA, and control groups. These treatments were continued for 3 weeks. A third operation was performed to evaluate treatment results. Then, the experimental treatments were halted and estrogen was initiated again to maintain estrus. After three additional weeks; i.e. after 9 weeks, the recurrence rate of endometrial foci was evaluated in a fourth operation and the rats were sacrificed. The volume of endometriotic foci and histopathology scores before and after treatment were compared. RESULTS: The respective mean volumes of the endometriotic foci after 3, 6, and 9 weeks were 86.4±21.2, 16.4±8.2, and 20.1±9.6 mm(3) in the theranekron group, 78.3±20.4, 42.6±13.5, and 66.7±16.2 mm(3) in the MPA group, and 91.8±30.2, 34.4±11.4, and 72.4±21.9 mm(3) in the LA group. The respective mean histopathology scores were 2.4±0.6, 1.8±0.6, and 1.6±0.6 in the theranekron group, 2.5±0.8, 2.0±1.1, and 2.7±1.0 in the MPA group, and 2.3±0.5, 2.1±1.2, 2.4±0.8 in the LA group. After 9 weeks, the mean volume of endometriotic foci and histopathology scores were significantly lower in the theranekron group. CONCLUSIONS: Theranekron caused more evident regression of endometriotic foci than MPA or LA in a rat model. After stopping the theranekron treatment, the recurrence rate was also lower than that of the other groups.

The protective effect of erythropoietin and dimethylsulfoxide on ischemia-reperfusion injury in rat ovary.

OBJECTIVES: The aim of this study was to investigate the effects of erythropoietin and dimethylsulfoxide in the recovery from ischemia-reperfusion injury in an experimental rat adnexal torsion model. STUDY DESIGN: Thirty-six Wistar-albino rats were divided into six groups. Except for the sham operation group, all groups were subjected to left unilateral adnexal torsion for 3h. Erythropoietin and dimethylsulfoxide were intraperitoneally administered 30min before the detorsion operation. Malondialdehyde and nitric oxide levels were detected from both the plasma and the tissue samples. The sections of the tissues were evaluated histologically. The results were analyzed by a one-way analysis of the variance (ANOVA) followed by the Duncan test for multiple comparisons using computer software, SPSS Version 15.0 for Windows. RESULTS: This study demonstrated that dimethylsulfoxide and erythropoietin pretreatment attenuated ischemia-reperfusion-induced lipid peroxidation, prevented post-ischemic ovarian injury and helped to maintain the ovarian morphology. Malondialdehyde levels of plasma and ovary were higher in the torsion and detorsion groups than the sham group. This showed that ischemia-reperfusion had caused lipid peroxidation of the ovarian tissue, thus leading to oxidative damage. One of the major findings of this study is that malondialdehyde was significantly decreased in the plasma of rats who were pre-treated with dimethylsulfoxide and erythropoietin before detorsion. This suggests that dimethylsulfoxide and erythropoietin might prevent oxidative damage in ovarian ischemia-reperfusion injury. Histological examination confirmed that reperfusion caused more detrimental effects than only ischemia, which could be at least partially prevented by dimethylsulfoxide and erythropoietin administration prior to detorsion. CONCLUSION: Erythropoietin and dimethylsulfoxide may have beneficial effects in ischemia-reperfusion injury in ovarian torsion.