Worker-like behavioral and physiological phenotype in queens with removed wings in a ponerine ant.

Many highly eusocial insects are characterized by morphological differences between females, which are especially pronounced in ants. How these differences associate with particular behavioral and physiological phenotypes can illuminate early ant evolution. In ants, the morphological queen usually possesses a larger thorax with wings compared with a wingless worker. While queens specialize in reproduction, workers help with non-reproductive tasks and show various levels of reproductive degeneration. Here, we investigated the level of behavioral and physiological plasticity within queens in the ant species Harpegnathos saltator, which shows limited queen-worker dimorphism. We found that the experimental removal of wings led to the expression of worker behaviors and physiology, by examining young queens with wings, known as alate gynes, and those whose wings have been experimentally removed or naturally shed, known as dealate gynes. Compared with alate gynes, dealate gynes displayed higher frequencies of behaviors that are naturally shown by workers during reproductive competition. In addition, dealate gynes exhibited a worker-like range of ovarian activity. Like workers, they lacked the putative sex pheromones on their cuticle characteristic of dispersing gynes. Because gynes activate a worker-like phenotype after wing removal, the essential difference between the queen and worker in this species is a dispersal polyphenism. If the queen plasticity observed in H. saltator reflects the early stages of ant eusociality, a dispersal dimorphism rather than a distinct reproductive dimorphism might represent an early step in ant evolution.

Resumption of ovarian activity following removal of a 4.7 mg deslorelin implant in queens.

Deslorelin implants are widely used in felines. Due to their prolonged duration cat breeders frequently request early implant removal. The interval between deslorelin implant removal and resumption of ovarian function in queens is unknown. The aim of this study was to evaluate the interval between the removal of a deslorelin implant and the resumption of ovarian activity in adult queens. Twenty-three queens were treated with a 4.7 mg deslorelin implant placed in the periumbilical area. In the 16 queens completing the study implants were surgically removed at 3, 6 or 9 months (n = 6, 4 and 6 queens, respectively). Queens received a GnRH stimulation test as part of their pre-treatment general and reproductive health check. Following implantation treatment, all queens in inter-oestrus-anoestrus at the time of treatment came in oestrus within 2-5 days. Starting 7-14 days following implant removal queens were checked every 1-2 weeks with reproductive ultrasonography, a vaginal smear and blood collection. The interval to resumption of ovarian function ranged from 3 to 7 weeks irrespective of treatment length and age of the queen but was longer when the implant was removed at decreasing photoperiod (p < .05). In conclusion, at least 3 weeks post-removal are needed during increasing photoperiod to achieve follicular development and oestrogen production sufficient to support oestrous behaviour in queens following removal of a 4.7 mg deslorelin implant, while this time may increase up to 7 weeks during decreasing photoperiod. Further studies are needed to assess the interval between removal of a deslorelin implant and occurrence of ovulation as well as fertility at the first oestrus after a deslorelin treatment.

Body status and blood metabolites profiles during resumption of postpartum ovarian activity in yak (Poephagus grunniens).

We examined the changes in body weight (BW), back-fat thickness (BFT) and blood metabolites in relation to postpartum (PP) ovarian activity status in twenty female yaks raised under semi-intensive system. BFT and ovarian activities, like follicle development, ovulation (OV) and corpus luteum (CL) development, were monitored from 4 to 15 weeks (wk) PP using ultrasonography. Resumption of ovarian activity was confirmed with ovulation of dominant follicle (DF) and subsequent CL development, and >1 ng/ml progesterone concentration in blood plasma sample after 1week of ovulation. Yaks were further classified as cyclic (with CL), acyclic (without CL), and cystic (with >25 mm follicular cyst; FC). Within 20 weeks PP, 60% yaks resumed cyclic ovarian activity, while 25% failed to initiate cycling activity, and 15% developed follicular cysts. In all categories of yak, BW gradually decreased (p < .05) till nadir; however, nadir reached earlier (p < .05) in acyclic yaks. BFT differed (p < .05) among the yak groups, but it tended to be higher in cyclic yaks as compared to acyclic and cystic. No difference (p > .05) in non-esterified fatty acids (NEFA) values was found among the different categories of yaks, whereas, beta-hydroxy butyrate (BHB) levels were higher in cystic animals as compared to acyclic and cyclic. Blood glucose levels decreased in all yaks during initial 2 weeks after calving. Our findings suggest that yaks with low BW, BFT and glucose levels, and higher BHB values were at risk of delayed resumption of ovarian activity and concomitant development of follicular cysts.

Ovarian activity in crossbred Thai native does during naturally occurring foot-and-mouth disease (FMD) virus infection.

This study aimed to compare the follicular dynamics in goats during naturally infected with foot-and-mouth disease virus (FMD) subjected to induced ovulations, and after disease recovery, crossbred Thai native does were synchronized with CIDR for 14 days, and then PGF2α and PMSG were administered on the day following CIDR removal. The ovarian activity was determined by transrectal ultrasonography. Clinical signs (fever, anorexia, lameness, and foot lesion) were observed on day 12 post-estrus (day 0, day of expected estrus). The study was carried out for 2 periods: FMD outbreak (day 0-day 21) and FMD recovery (day 63-day 84). Infected does were classified into two groups: (I) does without (n = 5) and (II) does with clinical signs (n = 5). The results showed that during FMD outbreak, the number of follicles/waves and number of follicles > 5 mm in ovulatory follicle wave of group II were lower than those of group I and those of its own group after FMD recovery (P<0.05). Higher in follicular regression rate were found in group II compared to group I in the does with 3 follicular waves during FMD outbreak (P<0.05). Moreover, during FMD outbreak, the does had lower number of follicles > 5 mm and longer day of emergence and day of largest follicles in ovulatory follicle wave than of those after FMD recovery. This observation demonstrated that FMD impaired folliculogenesis in goats, and the ovarian activity could be restored about 1 month after disease recovery.

Using in-line milk progesterone data to characterize parameters of luteal activity and their association with fertility in Holstein cows.

Our objectives were to characterize parameters of luteal activity based on milk progesterone concentration (P4c) data from before and after artificial insemination (AI) and to evaluate their potential association with fertility in Holstein cows. Records of AI events (n = 4,353) and of milk P4c (n = 158,961) obtained through an in-line milk analysis system (Herd Navigator, DeLaval International, Tumba, Sweden) from 1,891 lactations of 1,423 Holstein cows were evaluated. Milk P4c (ng/mL) were measured every 2.2 ± 1.9 d (mean ± standard deviation) between 23.6 ± 7.3 and 185.3 ± 56.7 d in milk. Variations in milk P4c of consecutive records were used to determine onset of luteal phase (increase in P4c from <5.0 to ≥5.0 ng/mL), luteal phase length (period, in days, of P4c ≥5.0 ng/mL), cessation of luteal phase (decline from ≥5.0 to <5.0 ng/mL, designated as P4c-decline), and pregnancy (AI followed by a luteal phase that remained uninterrupted until 50 d post-AI). The length of the luteal phase preceding AI, the highest P4c (P4c peak) during the luteal phase preceding AI, the lowest P4c preceding AI (P4c pre-AI) that followed a P4c-decline, and the interval between P4c-decline and AI were evaluated, as well as the interval between AI and onset of luteal phase, and P4c at early diestrus (4.5 ± 0.6 d post-AI), mid diestrus (10.0 ± 0.6 d post-AI), and late diestrus (14.1 ± 0.6 d post-AI). Data were analyzed using logistic regressions, and comparisons made based on quartiles and cut-points established by receiver operating characteristic curve analysis. Overall probability of pregnancy was 32.0%. Parameters associated with reduced probability of pregnancy (represented as percentage points decrease in the probability of pregnancy) were (1) luteal phase length >14.4 d (7.6% decrease), (2) P4c peak ≤24.7 ng/mL (4.5% decrease), (3) P4c pre-AI >0.5 ng/mL (5.5% decrease), (4) interval between P4c-decline and AI of >1.6 d (4.0% decrease), (5) interval between AI and onset of luteal phase of <7 or >11 d (9.3 and 12.1% decrease, respectively), and (6) P4c at early diestrus ≤0.7 or >3.5 ng/mL (15.2 and 6.7% decrease, respectively), (7) P4c at mid diestrus ≤12.4 ng/mL (12.5% decrease), and (8) P4c at late diestrus ≤22.7 ng/mL (9.7% decrease). The parameters of luteal activity associated with reduced probability of pregnancy established here could be used as benchmarks while developing recommendations to improve reproductive performance in herds using in-line milk progesterone monitoring.

Carryover effects of pre- and postweaning planes of nutrition on reproductive tract development and estrous cycle characteristics in Holstein heifers.

The objectives of this study were to investigate the carryover effects of differing pre- and postweaning planes of nutrition on prepubertal reproductive tract development and postpubertal estrous cycle characteristics in Holstein heifers. Heifer calves (n = 36) were randomly assigned to receive either a low or a high (5 or 10 L of whole milk/d, respectively) preweaning diet from 1 to 7 wk of age and either a low or a high (70 or 85% of concentrate dry total mixed ration, respectively) postweaning diet from 11 to 25 wk of age. Starting at wk 26 of age, heifers were subjected to weekly transrectal ultrasonography until wk 33 or until first ovulation to assess endometrial thickness and ovarian follicular count and size in the prepubertal phase. In a subset of heifers (n = 28), ovarian ultrasonography continued weekly until at least the second ovulation was confirmed; thereafter, ovarian dynamics (through ultrasonography) and blood progesterone (P4) were assessed every 2 d throughout 1 complete estrous cycle in the postpubertal phase. In the prepubertal phase, endometrial thickness (12.0 ± 0.4 vs. 10.8 ± 0.3 mm) and largest follicle size (11.8 ± 0.3 vs. 10.9 ± 0.2 mm) were greater in heifers fed the high postweaning diet than in those fed the low postweaning diet. Furthermore, the number of class 2 (6-9 mm) follicles was greater in heifers fed the high preweaning diet than in those fed the low preweaning diet (1.6 ± 0.1 vs. 1.1 ± 0.1), whereas the number of class 3 (>9 mm) follicles was greater in heifers fed the high postweaning diet than in those fed the low postweaning diet (1.2 ± 0.1 vs. 1.0 ± 0.1). In the postpubertal phase, overall corpus luteum and P4 dynamics did not differ among pre- or postweaning treatments; however, P4 at 4 d preceding luteolysis was lesser in heifers fed the high postweaning diet than in those fed the low postweaning diet (6.1 ± 0.4 vs. 7.7 ± 0.4 ng/mL). In addition, compared with heifers fed the low postweaning diet, those fed the high postweaning diet had a greater number of antral follicles (31.4 ± 2.2 vs. 21.4 ± 2.3) and tended to have more class 3 follicles (3.6 ± 0.3 vs. 2.7 ± 0.3). Results indicate positive carryover effects of increasing the preweaning plane of nutrition from 5 to 10 L of whole milk/d on prepubertal follicular growth in Holstein heifers. Furthermore, an increased postweaning plane of nutrition (85 vs. 70% of concentrate dry total mixed ration) advanced reproductive development through greater endometrial thickness and follicular growth in the prepubertal phase and increased the population of antral follicles in the postpubertal estrous cycle.

Effectiveness of controlled internal drug release device treatment to alleviate reproductive seasonality in anestrus lactating or dry Barki and Rahmani ewes during non-breeding season.

This study aimed to evaluate the effectiveness of hormonal treatments on ovarian activity and reproductive performance in Barki and Rahmani ewes during non-breeding season. Forty-eight multiparous ewes, 24 Barki and 24 Rahmani ewes were divided into two groups, 12 lactating and 12 dry ewes for each breed. Controlled internal drug release (CIDR) device was inserted in all ewes for 14 days in conjunction with intramuscular 500 IU equine chronic gonadotrophin (eCG) at day of CIDR removal. Data were analysed using PROC MIXED of SAS for repeated measures. Breed, physiological status and days were used as fixed effects and individual ewes as random effects. Barki ewes recorded higher (p < .05) total number of follicles, number of large follicles, serum estradiol concentration and estradiol: progesterone (E2 :P4 ) ratio compared to Rahmani ewes. Lactating ewes recorded higher (p < .05) number of small follicles and lower concentration of total antioxidant capacity (TAC) compared to dry ewes. Number and diameter of large follicles recorded the highest (p < .05) values accompanied with disappearance of corpora lutea at day of mating. Serum progesterone concentration recorded lower (p < .05) value at day of mating and the highest (p < .05) value at day 35 after mating. CIDR-eCG protocol induced 100% oestrous behaviour in both breeds, but Rahmani ewes recorded longer (p < .05) oestrous duration compared to Barki. Conception failure was higher (p < .05) in Barki compared to Rahmani ewes. In conclusion, CIDR-eCG protocol was more potent in improving ovarian activity in Barki compared to Rahmani ewes, but this protocol seems to induce hormonal imbalance in Barki ewes that resulted in increasing conception failure compared to Rahmani ewes.

Effects of feed supplementation on growth, blood parameters and reproductive performance in Sanga and Friesian-Sanga cows grazing natural pasture.

This study determined the effects of feed supplementation during the postpartum period on the weight gain, milk yield, blood profiles and reproductive performance of Sanga and Friesian-Sanga cows grazing on natural pasture. 20 Sanga and 20 Friesian-Sanga cows were randomly allocated either to serve as a control on grazing only or to be supplemented with 2.5 kg of concentrate a day for 10 weeks during the dry season. Each week, all cows were weighed and scored for body condition. Partial milk yield of cows was determined daily. Plasma concentrations of blood metabolites were assessed fortnightly from weeks 1 to 10 postpartum. Resumption of postpartum ovarian activity was determined by measuring progesterone concentration in the plasma from weeks 1 to 10. Supplemented cows had a better body condition score (6.2 versus 5.8; P < 0.05) and higher partial milk yield (1.94 versus 1.55 L/day; P < 0.01) than non-supplemented cows. Sanga cows had a better body condition score (6.2 versus 5.8; P < 0.05) but lower milk yield (1.58 versus 1.92 L/day; P < 0.01) than the Friesian-Sanga crossbreds. Total protein (P < 0.05) and albumin (P < 0.01) concentrations were higher in the supplemented than in the non-supplemented cows. Sanga cows recorded higher globulin (P < 0.05) and total cholesterol (P < 0.01) but lower albumin (P < 0.01) concentrations than Friesian-Sanga crossbred cows. Feed supplementation did not affect (P < 0.05) the interval from calving to resumption of ovarian activity, and the days to resumption of ovarian activity in the Sanga and Friesian-Sanga cows were also similar (P > 0.05). The results demonstrate the beneficial effects of feed supplementation in terms of improved body condition and metabolic status and increased milk yield.

Effect of season and breed group on the follicular population and cyclicity of heifers under tropical conditions.

The aim was to determine the effect of season and breed group on follicular population, and presence and size of CL of heifers under tropical conditions. The seasons were hot-dry (March-June), hot-humid (July-October), and fresh-humid (November-February). Thirty Zebu (Brahman) and 38 F1 (Simmental × Brahman) heifers were used. Five evaluations were made in each season, at intervals of 7 days, to assess ovarian activity by ultrasound. Follicles were classified as small (≤4 mm), middle (4.1-8 mm), and large (≥8.1 mm) sizes, and also the size of CL, when present, was measured. Data were analyzed using analysis of variance and logistic regression procedures. Mean number of small follicles was 11.6 ± 2.3 with no effect of season, breed group, or their interaction (P > 0.05). Mean number of middle follicles was influenced by season and breed group; the highest average was found in the fresh-humid season (4.0 ± 0.2) and in F1 heifers (3.6 ± 0.2; P < 0.05). The highest mean number of large follicles was in the hot-humid season (1.4 ± 0.1; P < 0.05). The highest maximum follicle diameter (MFD) mean was registered in the hot-humid season (1.3 mm; P < 0.05) and the lowest proportion of heifers with CL occurred in fresh-humid season (33.3%; P < 0.05). No effect of season, breed group, and interaction on the maximum diameter of the CL was found. In conclusion, season was a very important source of variation. Heifers in the hot-humid season had the largest follicles and MFD, and better cyclicity.

Ovarian function during hormonal contraception assessed by endocrine and sonographic markers: a systematic review.

This systematic review focuses on the literature evidence for residual ovarian function during treatment with hormonal contraceptives. We reviewed all papers which assessed residual ovarian activity during hormonal contraceptive use, using endocrine markers such as serum anti-Müllerian hormone (AMH) concentrations, FSH, LH, oestradiol, progesterone and sonographic markers such as antral follicle count (AFC), ovarian volume and vascular indices. We considered every type (oestroprogestin or only progestin) and dosage of hormonal contraceptive and every mode of administration (oral, vaginal ring, implant, transdermal patch). We performed an electronic database search for papers published from 1 January 1990 until 30 November 2015 using PubMed and MEDLINE. We pre-selected 113 studies and judged 48 studies suitable for the review. Most studies showed that follicular development continues during treatment with hormonal contraceptives, and that during treatment there is a reduction in serum concentrations of FSH, LH and oestradiol, and also a reduction in endometrial thickness, ovarian volume and the number and size of antral follicles. The ovarian reserve parameters, namely AFC and ovarian volume, are lower among users than among non-users of hormonal contraception; regarding the effect of hormonal contraception on AMH, there are still controversies in the literature.

A randomised study comparing the effect on ovarian activity of a progestogen-only pill (POP) containing desogestrel and a new POP containing drospirenone in a 24/4 regimen.

OBJECTIVES: Progestogen-only pills (POPs) are safer with respect to cardiovascular risks than contraceptives containing estrogens. Despite the increased contraceptive efficacy of a desogestrel-only pill compared with a traditional POP, POPs are still not widely used due to an unpredictable bleeding pattern. A new POP containing 4 mg drospirenone has been developed with a 24/4 intake regimen which may improve the bleeding pattern. The objectives of this study were to investigate ovulation inhibition with the new drospirenone-only pill in comparison with the desogestrel-only pill and, in addition, to assess the effects on cervical mucus permeability and bleeding. METHODS: Sixty-four healthy volunteers with proven ovulatory cycles were randomised and treated with either the drospirenone-only or the desogestrel-only pill during two 28-day cycles. Follicular diameter, endometrial thickness, and serum estradiol (E2) and progesterone concentrations were measured and Hoogland scores were determined. Additionally, cervical mucus scores, bleeding and return of ovulation were assessed. RESULTS: Both treatments effectively inhibited ovulation. Follicular diameter, E2 levels and Hoogland scores were equal, demonstrating efficient ovarian suppression. One subject in each group had a Hoogland score of 6, but the criteria for normal luteal activity were not fulfilled. In both groups, ovulation did not occur before day 9 of the post-treatment cycle. Cervical mucus permeability was suppressed in both groups. The median number of bleeding and spotting days was lower in the drospirenone group. CONCLUSIONS: The new drospirenone-only pill inhibited ovulation as effectively as the desogestrel-only pill despite the 4-day hormone-free interval.

A phase 1, multicentre, open-label study to evaluate ovarian follicular activity and hormone levels with an extended-regimen combined oral contraceptive with low-dose ethinyl estradiol supplementation.

OBJECTIVES: To evaluate the effect on ovarian follicular activity of the 91-day extended-regimen combined oral contraceptive (COC), consisting of 84 days of levonorgestrel (LNG)/ethinylestradiol (EE) 150 µg/30 µg tablets plus seven days of EE 10 µg tablets in place of placebo. METHODS: This was a phase 1, open-label study. Ovarian follicular activity was classified via the Hoogland and Skouby method. Safety and tolerability as well as return to ovulation were assessed. RESULTS: Of the 35 subjects included in the efficacy analysis, luteinized, unruptured follicles, or ovulation were detected in 0 of 35 cycles during the first 28-day interval; 1 of 35 cycles (2.9%) in the second 28-day interval; and 2 of 35 cycles (5.7%) in the final 35-day interval. The ovarian activity rate over the entire 91-day treatment period was 2.9%. There was a low incidence of treatment-emergent adverse events. Ovulation returned in most subjects (77.1%, 27/35) within 32 days following the last dose of COC. CONCLUSIONS: The 91-day extended-regimen COC with low-dose EE supplementation was found to be effective in suppressing ovarian activity and inhibiting ovulation and was well tolerated. Return to ovulation was rapid, occurring within approximately one month after discontinuation of COC.

Effect of short-term supplementation with rumen-protected fat during the late luteal phase on reproduction and metabolism of ewes.

This study was designed to study the effect of short-term supplementation with rumen-protected fat during the late luteal phase on reproduction and metabolism of sheep during breeding season. Seventy-six ewes (Rahmani, Barki and Awassi × Barki) were allocated to two groups considering genotype: the control ewes (C-group) received a maintenance diet, and the fat-supplemented ewes (F-group) received the maintenance diet plus 50 g/head/day of rumen- protected fat (Megalac) for 9 days during which oestrus was synchronized. The latter had been accomplished using double intramuscular injection of prostaglandin F2α (PGF2α ) 11 days apart. Ovarian activity, serum concentration of cholesterol, glucose, insulin and reproductive performance variables were recorded. Data were analysed considering treatment (group) and genotype. Supplementation had positive effects on the overall mean serum concentrations of cholesterol (p < 0.05), glucose (p < 0.05) on day 6 of nutritional treatment and insulin (p = 0.07) on day 8. Fat supplementation did not affect the total number of follicles, follicle populations and ovulation rate. However, fat-supplemented Rahmani ewes tended to have higher ovulation rate compared with other breeds (treatment × breed interaction, p = 0.06). Treatment also did not affect the mean concentration of serum estradiol or progesterone. Supplemented ewes had higher conception (p = 0.06) and lambing rates (p < 0.05) compared with control. In conclusion, short-term supplementation with rumen-protected fat as a source of energy around breeding time improved metabolism, conception and lambing rates of ewes without effects on steroidogenic capacity and ovarian activity being apparent.

Impact of presynchronization and Ovsynch on early postpartum ovarian activity and fertility of dairy cows in Libya.

Background: Reproductive efficiency affects dairy cow profitability. Ovarian function in postpartum (P.P.) has been better understood using ultrasound and hormonal assays. Optimizing ovulation synchronization and carefully timing artificial insemination (TAI) can greatly enhance reproductive rates in dairy cows. Aim: This experiment was designed to investigate the reproductive performance and ovarian activity in early postpartum lactating dairy cows using the Presynch-PGF2α, Ovsynch protocol, and TAI. Methods: Randomly the cows were assigned to a control group and a treatment group, based on the chronological order of their calving date. On day 14 P.P., both groups received two cloprostenol treatments, 14 days apart. Ultrasonographic inspections were conducted on day 14 to check ovarian activity and uterine contents. On day 11, after presynchronization, cows in the treatment group were given 100 µg IM. of cystorelin, followed by a luteolytic dose of 500 µg IM., cloprostenol on day 7, and a second dose of cystorelin on day 8 (36 hours later). After the second cystorelin injection by 16-20 hours, cows were inseminated, while the control group had all cows displaying spontaneous estrus between day 0 and day 28 were artificially inseminated. Results: Ovarian activity began to improve at 82.61% on day 19 P.P., with complete recovery between days 24 and 27 P.P. The second cloprostenol injection approached, causing follicular size to reach 8.41 ± 1.04 mm. After the second injection, ovarian activity switched from follicular to luteal, with corpus luteum rates of 23.91% and 26.1%. The presynchronized PGF2α regimen significantly enhanced ovarian activity from days 19-35 P.P. Ovulation and pregnancy rates in the Ovsynch group were 54.2% and 41.7% at the first timed artificial insemination (TAI), compared to 54.5% and 31.8% in the control group. There was no significant impact between them; it was just high in the presynchronized Ovsynch group. However, the P.P. period was minimized to 47-49 days till the first AI reached a 41.7% pregnancy rate and 20.8% at the second AI, for an overall 62.5%. Conclusion: The current study concludes that presynchronization during preservice in clinically normal P.P. dairy cows reduces P.P. duration, increases ovarian activity performance, and reduces ovarian dysfunctions from day 19 to day 35 P.P., as well as improves the pregnancy rate.

Targeted Glutamate Supply Boosts Insulin Concentrations, Ovarian Activity, and Ovulation Rate in Yearling Goats during the Anestrous Season.

The neuroendocrine regulation of the seasonal reproductive axis requires the integration of internal and external signals to ensure synchronized physiological and behavioral responses. Seasonal reproductive changes contribute to intermittent production, which poses challenges for optimizing goat product yields. Consequently, a significant objective in seasonal reproduction research is to attain continuous reproduction and enhance profitability in goat farming. Glutamate plays a crucial role as a modulator in several reproductive and metabolic processes. Hence, the aim of this study was to evaluate the potential impact of exogenous glutamate administration on serum insulin concentration and ovarian function during the out-of-season period in yearling goats. During the anestrous season, animals were randomly located in individual pens to form two experimental groups: (1) glutamate (n = 10, live weight (LW) = 29.1 ± 1.02 kg, body condition score (BCS) = 3.4 ± 0.2 units) and (2) control (n = 10; LW = 29.2 ± 1.07 kg, BCS = 3.5 ± 0.2), with no differences (p < 0.05) regarding LW and BCS. Then, goats were estrus-synchronized, and blood sampling was carried out for insulin quantification. Ovaries were ultrasonographically scanned to assess ovulation rate (OR), number of antral follicles (AFs), and total ovarian activity (TOA = OR + AF). The research outcomes support our working hypothesis. Certainly, our study confirms that those yearling goats treated with exogenous glutamate displayed the largest (p < 0.05) insulin concentrations across time as well as an augmented (p < 0.05) out-of-season ovarian activity.

Effect on ovarian activity and ovulation inhibition of different oral dosages of levonorgestrel.

OBJECTIVES: To investigate the effect of different oral dosages of levonorgestrel (LNG) on ovarian activity and to identify the lowest dosage at which no ovulation occurred. Secondary objectives were to assess return of ovulation after stopping treatment, bleeding pattern, pharmacokinetic (PK) parameters and safety and tolerability. STUDY DESIGN: A parallel-group study with adaptive design was performed in 90 healthy women with proven ovulatory cycles. Investigated dosages were LNG 0.095, 0.115 and 0.135 mg per day. Measurements of follicular growth and estradiol (E2) and progesterone concentrations were performed every 3 (±1) days during a 56-day treatment and a post-treatment period. Follicle-stimulating hormone and luteinizing hormone concentrations and multiple-dose PK parameters were determined during treatment. RESULTS: Two normal ovulations occurred in the LNG 0.095 mg group, none in the higher dose groups. Most subjects had active follicle-like structures without ovulation (Hoogland-Skouby scores 4). Ovarian activity was more suppressed in the highest dose group than in the other groups. Mean E2 concentrations were 241, 219 and 180 pmol/L during treatment with 0.095, 0.115 and 0.135 mg per day, respectively. PK results showed dose-proportionality. Most subjects ovulated during the post-treatment period. CONCLUSION: LNG 0.115 mg per day was the lowest effective dosage for consistent ovulation inhibition. All investigated dosages were safe and well-tolerated, and mean E2 concentrations were sufficient for prevention of hypoestrogenic side effects. IMPLICATIONS: Marketed progestogen-only pills (POP) containing 0.03 mg LNG do not consistently inhibit ovulation. Increasing the dosage to 0.115 mg or 0.135 mg per day, resulting in consistent ovulation inhibition, may improve the contraceptive efficacy of the LNG-POP.

Clinical use of Anti-Müllerian Hormone to monitor resumption of ovarian activity following removal of a 4.7 mg deslorelin implant in queens.

OBJECTIVE: The use of deslorelin implants to control reproduction in cats is increasing but because of its prolonged duration, cat breeders often request 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 which deslorelin implants were surgically removed after 3, 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 with reproductive ultrasonography, a vaginal smear and blood collection to assay AMH concentrations. RESULTS: AMH concentrations decreased significantly at the end of the 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 3.9 ± 0.7 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.

Maximizing the reproductive performances of anestrus dairy buffalo cows using GnRH analogue-loaded chitosan nanoparticles during the low breeding season.

The present study was designed to evaluate the efficiency of GnRH-loaded chitosan-TPP nanoparticles (GnRH-CsNPs) to improve the reproductive performance of anestrus buffaloes during the summer. Egyptian buffaloes (n = 50) were synchronized for estrus either with the ovsynch protocol (OVSs, n = 20) or with the modified ovsynch protocol (OVSm, n = 30) using GnRH-CsNPs. Sera samples were collected on days 0, 7, and 10 (insemination day); and days15 and 30 post insemination for estradiol (E2) and progesterone (P4) determination. The follicles were monitored on day 0 and day 10. CLs diameter and pregnancy diagnosis were scanned on day 30 post insemination. Using a half dose of GnRH as GnRH-CsNPs in the OVSm improved (P < 0.05) the number of total and large follicles, and the total surface area of subordinate and large follicles compared to the OVSs protocol. The OVSm increased (P < 0.05) the largest follicles diameter on day 10 and CLs diameter on day 30 post insemination compared to the OVSs protocol. E2 concentration was greater (P < 0.05) on insemination day, and P4 concentrations were higher (P < 0.05) on days 15 and 30 post insemination in the OVSm than in the OVSs. The estrus induction rate was 80 % higher (P < 0.05) in the OVSm and cows exhibited estrus within 17.54 h earlier than the OVSs (50 % within 42 h), respectively. The conception rate increased in OVSm compared to OVSs (75 vs. 40 %, respectively). In conclusion, nanofabrication of GnRH allowed to reduce hormonal dose to 50 % without any adverse effects on fertility, and improved ovarian activity and reproductive performance of anestrus buffaloes during the low breeding season.

Resumption of Cyclic Ovarian Activity by Herbal Preparation AyuFertin in Bulgarian Murrah Buffaloes at Early Postpartum.

This study evaluates the phytochemical composition and ability of herbal preparation AyuFertin, supplemented shortly after calving, to resume the cyclic ovarian activity in postpartum Bulgarian Murrah buffaloes. In total, 13 healthy Bulgarian Murrah buffaloes at the age of 4-10 years, calved in March-April 2019 were involved in the experiment. Seven experimental buffaloes were treated individually per os with AyuFertin according to producer instruction. All animals were subjected to regular ultrasound examination of ovaries. GC-MS analysis of fatty acids composition and HPLC-DAD analysis of carotenoid and tocopherol content in AyuFertin were conducted. The determination of estrus occurrence and natural mating were done by a fertile bull. The development of the large follicles (12.5-14.3 mm) in 85.7% of treated animals was observed on day 24 postpartum compared to 0% in controls. Clinical signs of estrus were recorded in 71.4% of the animals, followed by an 80% pregnancy rate versus 16% in controls within 70 days after calving. In conclusion, the supplementation of the bioactive herbal product AyuFertin from day 21 postpartum can stimulate the follicular growth in the buffalo's ovary, which leads to the development of follicles with ovulatory capacity, followed by successful ovulation. The above-mentioned treatment resulted in a better pregnancy rate in the treated multiparous compared to the control buffaloes bred by natural service.

Hormonal Characteristics of Women Receiving Ovarian Tissue Transplantation with or without Endogenous Ovarian Activity.

Ovarian tissue cryopreservation (OTC) and transplantation of frozen/thawed ovarian tissue (OTT) are used for fertility preservation in girls and women. Here, we evaluated the hormonal characteristics of women with or without postmenopausal levels of FSH at the time of OTT to study differences and conditions that best support the initiation of ovarian function. A total of 74 women undergoing OTT (n = 51 with menopausal levels of FSH; n = 23 with premenopausal levels) were followed by measurements of FSH, LH, AMH, and oestradiol. Concentrations of FSH and LH returned to premenopausal levels after 20 weeks on average, with a concomitant increase in oestradiol. Despite resumption of ovarian activity, AMH concentrations were in most instances below the detection limit in the menopausal group, suggesting a low ovarian reserve. Despite a higher age in the premenopausal group, they more often experienced an AMH increase than the menopausal group, suggesting that conditions in the premenopausal ovary better sustain follicle survival, perhaps due to the higher concentrations of oestradiol. Collectively, this study highlights the need for improving follicle survival after OTT. Age and the amount of tissue transplanted are important factors that influence the ability to regain ovarian activity and levels of FSH may need to be downregulated and oestradiol increased prior to OTT.