Mean Number Of Large Follicles Research Articles

Different doses of pFSH are effective to promote follicular growth, superovulatory response, and embryo yield in White Dorper ewes

This study evaluated the effect of 250, 333, or 400 IU of a commercial porcine stimulating-follicle hormone (pFSH) on follicular growth, superovulatory (SOV) response, and embryo yield in White Dorper sheep. Ewes received an induced-ovulation protocol (D0 = progesterone (P4) device insertion) and superovulation starting 60 h before P4 withdrawal (D9), which consisted of six decreasing doses of 250 IU (G250; n = 15), 333 IU (G333; n = 15), or 400 IU (G400; n = 14) of pFSH. Ewes also received 50 µg of gonadotropin-releasing hormone (GnRH) analog on D10 and 300 IU of hCG on D13. Ewes were mated and submitted to non-surgical embryo recovery (NSER). Ultrasound evaluations were performed on D6, D7, D8, D9, and D16. The overall responding donor rate (≥3 CL) was 86.4% (38/44). The mean number of large follicles was higher (P < 0.05) in all groups on D8 (6.2 ± 0.9, 7.7 ± 0.9, and 8.3 ± 1.1) and D9 (11.1 ± 0.6, 10.4 ± 1.0, and 11.5 ± 0.9). Non-surgical embryo recovery procedures were successfully performed in 60.5% (23/38) of females. The CL count in successfully flushed ewes was greater (P < 0.05) in G333 (12.7 ± 2.3) and G400 (12.0 ± 1.3) than in G250 (6.0 ± 1.1). The recovery rate (44.4%, 57.3%, and 50.0%) and numbers of transferable embryos (2.3 ± 1.1, 6.1 ± 2.6, and 4.5 ± 1.3) did not differ (P > 0.05) among groups. All protocols were efficient in promoting follicular growth and adequate superovulatory response and embryo yield.

Increased number of large non-atretic follicles and co-dominance effects account for high litter sizes in Bonga sheep.

To understand the ovarian basis for prolificacy of Bonga sheep, a total of 31 ewes were selected based on litter size (LS) records and divided into two groups: High Prolificacy (HP) (n=20) with LS≥2 and Low Prolificacy (LP) (n=11) with LS=1. At a synchronized estrus, follicular dynamics were determined using transrectal ultrasonography. Plasma estradiol concentrations were also monitored. In total 27 ewes were observed in estrus being 9/11 LP (82%) and 18/20 HP (90%). On the day of estrus (day 0), the mean number of large follicles was higher (p<.05) in HP (1.78±0.19) than in LP (1.0±0.28) ewes. Prior to estrus, more (p<.05) medium follicles were visible for HP compared to LP ewes. Plasma estradiol concentrations were higher in HP compared to LP ewes (18.91±0.41 vs. 14.51±0.65pg/ml; p<.05) and similarly was ovulation number (2.3±0.15 vs. 1.28±0. 14; p<.05). Higher ovulation rates and litter size in Bonga sheep are evidenced by the previous presence of more large follicles and the existence of co-dominance effects as most likely medium follicles are selected to ovulate.

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 7days, to assess ovarian activity by ultrasound. Follicles were classified as small (≤4mm), middle (4.1-8mm), and large (≥8.1mm) 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 (1.3mm; 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.

Characterization of ovarian follicular development and steroid profile during estrous cycle and seasonal anestrous in buffalo

The experiment was conducted to study ovarian follicular population, its diameter, steroid profile (estradiol 17ß and progesterone) and corpus luteum development during estrous cycle and seasonal anestrous in Murrah buffaloes. They were categorized into 2 groups based on the estrus signs i.e. cyclic (6) and anestrous (6) and subjected to ultrasound scanning of ovaries on day 0 (day of estrus in cyclic and day of first scanning in anestrous buffaloes), 6, 10 and 16 using B-mode scanner equipped with 6.0 MHz linear array transducer. Blood samples were collected on the above days for the estimation of the progesterone and estradiol-17ß. The mean number of small follicles on day 0 and 10 and medium follicles on day 10 were significantly higher within as well as between the cyclic and anestrous buffaloes, while mean number of large follicles on day 0, 10 and 16 were significantly higher in the cyclic as compared to anestrous buffaloes. However, mean number of total follicles were significantly higher in cyclic as compared to anestrous buffaloes on all the days of scanning. The maximum diameter of large follicle was observed in cyclic buffaloes on day 0 (1.40±0.49 cm). The diameter of CL increased with its development and reached to its peak on day 10 (1.39±0.04 cm), thereafter, it reduced on day 16 (0.72±0.30 cm) of the cycle. The mean serum progesterone concentration was significantly higher on day 6, 10 and 16 than day 0 of the estrous cycle indicating development of functional corpus luteum, however, mean serum estradiol-17ß concentration was significantly higher on day 0 than the other days of cycle signifying follicular growth and development secreting higher amount of estrogen.

Effects of eCG injection combined with FSH and GnRH treatment on the lambing rate in synchronized Afshari ewes

Due to the substantial contribution of lambing rate to profitability of sheep holders, the present trial was investigated the effects of eCG injection combined with FSH and GnRH administrations on ovarian follicular development and the lambing rate in Afshari ewes during breeding season. The estrous cycle of 64 cycling multiparous Iranian Afshari ewes, weighing 65±2.5kg, was synchronized using CIDR's, inserted for 14 days. eCG (300IU) was injected to ewes a day before CIDR removal. The ewes were allocated randomly to 1 of 4 groups (n=16/group). Control group did not receive FSH treatment. In FSH/0h, FSH/12h and FSH/24h groups, ewes received 10mg FSH at CIDR removal, 12 or 24h later, respectively. GnRH (50μg) was administered 48h following CIDR removal to half of each group of ewes. Ewes were mated with the proven rams. Ovarian follicular activity was monitored by transrectal ultrasonography at CIDR removal (day 0) and a day later (day 1). The repeated data analyzed using the mixed procedure of SAS (9.1). Effects of weight and age of ewes were added as a covariate to the model. The reproductive parameters (%) were analyzed using the chi-square test. The results have been showed that FSH treatment did not increase the mean number of small and medium sized follicles. Following FSH treatment, the mean number of large follicles had a tendency to increase (P<0.1) in FSH/12h group of ewes. Lambing rate in control, FSH/0h, FSH/12h and FSH/24h were 137.50%, 131.25%, 150.00% and 181.25%, respectively. The lambing rate and litter size increased to ≥150% (P<0.05) in groups of ewes which received GnRH. FSH/24h group of ewes had a significantly higher lambing rate, litter size and multiple birth rate (P<0.05) compared to other treatment groups. In conclusion, GnRH injection 48h after CIDR removal and eCG injection increase the lambing rate, litter size and multiple birth rates in ewes. The lambing rate (>180%) was greater in ewes which eCG injection was combined with FSH treatment 24h after CIDR removal with or without GnRH injection. These results indicate that lambing rate and litter size after CIDR and eCG treatment can be increased when GnRH is administered 48h after CIDR removal or when FSH is given 24h after CIDR removal.

Effect of gonadotropin-releasing hormone (GnRH) treatment on multiple births in Afshari ewes

The purpose of this study was to investigate the effects of gonadotropin-releasing hormone (GnRH) administration on the induction of multiple births in synchronized Afshari ewes. 16 cycling, multiparous fat-tailed Iranian Afshari ewes, weighing 66.5 ± 2.5 kg, were used in the trail. Estrus was synchronized using controlled internal drug release CIDR’s; inserted for 14 days. Pregnant mare serum gonadotrophin (PMSG) (300 IU) was injected to ewes a day before CIDR removal. The ewes was randomly allocated to two groups (n = 8). Synchronization treatment was initiated with a week interval in two groups (weeks 1 and 2). 24 h following CIDR removal (day 1), GnRH (50 µg) was administered to half of each group ewes (GnRH and control groups), and ewes mated with the proven rams. Pregnancy was diagnosed with the aid of transabdominal ultrasonograpy 30 days after mating. Ovarian follicular activity was monitored with the aid of transrectal ultrasonograpy on the days of CIDR removal and at estrus (approximately day 1). Following PMSG treatment, the mean number of large follicles on total ovaries increased from CIDR removal to estrus 1.48 ± 0.71 vs. 2.85 ± 0.82 (P < 0.05). Lambing rate in GnRH group (162.5%) was higher (P < 0.05) compared to the control group (125%). The mean weights of lambs born in the GnRH and control groups were 5.5 ± 0.1 and 5.2 ± 0.1, respectively.

Ovarian follicular response to different hormonal stimulation treatments in Canindé goats

The objective of the present study was to evaluate the effect of different hormonal stimulation treatments on the antral follicular population of naturalized Canindé goats. Adult goats ( n = 17) having estrous cycles at regular intervals were treated with intra-vaginal sponges containing 60 mg medroxyprogesterone acetate for 11 days, combined with an application of 50 μg d-cloprostenol on the Day 8 of treatment. For ovarian stimulation, goats were distributed into the following experimental groups: (a) multiple doses (MD), with a total of 120 mg NIH-FSH P1 in five intramuscular injections (30/30; 20/20 and 20 mg) at 12-h intervals; (b) three doses (TD), with a total of 120 mg NIH-FSH P1 in three intramuscular injections (60; 40 and 20 mg) at 24 h intervals; (c) one dose (OD), which consisted of the use of 70 mg NIH-FSH P1 combined with 200 IU eCG administered intramuscularly 36 h before sponge removal. In the MD and TD groups, FSH injections were begun on the Day 8 of progestagen treatment. The ovaries of all animals were observed by transrectal real time ultrasonography (TRU) during the follicular stimulation protocols. All follicles ≥2 mm were counted, measured and classified according to greatest diameter. The ultrasonographic assessment of the ovaries provided for well-defined ovarian structures. At the time of insertion of the sponges (Day 0), significant differences were observed ( P < 0.05) for the mean number of large follicles between the treated groups. Meanwhile, on Day 11, the three treatments did not differ ( P < 0.05), regardless of the follicular category. The diameter of small follicles was similar in MD, TD and OD during the whole period of the study. In the TD group, diameter of the large follicles was less ( P < 0.05) on Day 10 when compared to MD and OD. However, these differences were not observed on Day 11. In conclusion, the three treatments produced comparable distribution of the follicular populations. However, the single dose treatment can be preferred because of its simplicity and efficacious follicular response.

Effect of gonadotropin-releasing hormone (GnRH) treatment on multiple births in Afshari ewes

The purpose of this study was to investigate the effects of gonadotropin-releasing hormone (GnRH) administration on the induction of multiple births in synchronized Afshari ewes. 16 cycling, multiparous fat-tailed Iranian Afshari ewes, weighing 66.5 ± 2.5 kg, were used in the trail. Estrus was synchronized using controlled internal drug release CIDR’s; inserted for 14 days. Pregnant mare serum gonadotrophin (PMSG) (300 IU) was injected to ewes a day before CIDR removal. The ewes was randomly allocated to two groups (n = 8). Synchronization treatment was initiated with a week interval in two groups (weeks 1 and 2). 24 h following CIDR removal (day 1), GnRH (50 µg) was administered to half of each group ewes (GnRH and control groups), and ewes mated with the proven rams. Pregnancy was diagnosed with the aid of transabdominal ultrasonograpy 30 days after mating. Ovarian follicular activity was monitored with the aid of transrectal ultrasonograpy on the days of CIDR removal and at estrus (approximately day 1). Following PMSG treatment, the mean number of large follicles on total ovaries increased from CIDR removal to estrus 1.48 ± 0.71 vs. 2.85 ± 0.82 (P < 0.05). Lambing rate in GnRH group (162.5%) was higher (P < 0.05) compared to the control group (125%). The mean weights of lambs born in the GnRH and control groups were 5.5 ± 0.1 and 5.2 ± 0.1, respectively.

Effects of the Rate and Duration of Physiological Increases in Serum FSH Concentrations on Emergence of Follicular Waves in Cyclic Ewes1

Large antral follicles grow in waves in the ewe, with each wave triggered by a peak in serum FSH concentrations. In this study, our objectives were to determine if the slope of the rise in the FSH peak affects the ability of the peak to trigger wave emergence (experiment 1), and whether increasing serum FSH concentrations and holding them at peak concentrations would provide a stimulus for constant emergence of large antral follicles (experiment 2). In experiment 1, cyclic ewes received ovine FSH (n = 6; 0.1 μg/kg, s.c.) or vehicle (n = 6; control) every 6 h for 42 h. This treatment created a peak in serum FSH concentrations (P < 0.05) during the early growth phase of the first follicular wave of the interovulatory interval and enhanced the growth of follicles in that wave (P < 0.05), but did not trigger emergence of a follicular wave. In experiment 2, cyclic ewes were infused constantly with oFSH (1.98 μg/h; n = 6) or vehicle (control; n = 6) for 60 h starting at the time of the second endogenously driven FSH peak of the interovulatory interval. Infusion of oFSH resulted in a super-stimulatory effect, with a peak in the mean number of large follicles (≥5 mm) on Day 2 after the start of FSH infusion (13 ± 1.2 large follicles per ewe, 1.8 ± 0.2 in control ewes; P < 0.001). In conclusion, exposing early growing antral follicles in a wave to a gradual increase in serum concentrations of FSH enhanced their growth, but did not trigger the expected new follicular wave, and infusion of a dose of oFSH within the physiological range caused a super-ovulatory response in cyclic ewes.

Application of Ultra-low-dose Incremental Gn Protocol in Controlled Ovarian Hyperstimulation of the Patients with Ovary Hyperreaction

Objective To explore the clinical outcome of ultra-low-dose incremental protocol in the controlled ovarian hyperstimulation (COH) for the ovary hyperreaction patient. Methods A prospective, randomized, controlled study was conducted between June 2006 and February 2008 on 120 women who underwent COH. The patients' clinic outcomes were compared between ultra-low-dose incremental protocal (experimental group, n=60) and other ovulation stimulating protocols (control group, n=60). Results The mean number of large follicles (≥14 mm) on the day of oocytes retrivaling, the mean number of harvested oocytes and the incidence rate of OHSS were significantly lower in experimental group. However, the gonadotropin stimulating time was significantly longer in experimental group. And the rate of leading follicle punctuation was also higher in this group when compared with control group. The clinical pregnant rate, the mean number of gonadotropin ampoules, the cancel rate were similar in the two groups. Conclusion The application of ultra-low-dose incremental protocal in the COH for the ovarian hyperreaction patients is able to effectively reduce the risk of occurrence of OHSS under the precondition of assurance of pregnancy rate. It is a safe and more effective COH program.

298 EFFECT OF TWO DIFFERENT DOSES OF FOLLICLE-STIMULATING HORMONE IN ALUMINUM HYDROXIDE GEL BY A SINGLE INJECTION ON ESTRUS AND SUPEROVULATORY RESPONSE IN HOLSTEIN CATTLE

We investigated the effect of administration of different dosage of FSH in aluminum hydroxide gel (Gel; an adjuvant and absorbent of large molecules) by a single injection on induction of estrus, superovulatory response, and embryo recovery in Holstein cattle. In this study, six cloprostenol-synchronized [PGF (0.75 mg, IM); Clopromate C; Sumitomo Pharmaceuticals Co., Tokyo, Japan], nonlactating Holstein cows were divided into three groups (Gel-40, Gel-30, Controls) between days 8 and 11 (day 0 = the day of estrus) in a Latin square design. Forty mg (Gel-40 group) FSH (Antrin-R10; Kawasaki Mitaka Pharmaceutical Co., Tokyo, Japan) or 30 mg (Gel-30 group) FSH were mixed with 5 mL Gel and administered by a single injection into fat in the ischiorectal fossa. The control group received 40 mg pFSH twice daily for 4 d in decreasing doses (8, 8, 6, 6, 4, 4, 2, and 2 mg) into the ischiorectal fossa. Then, all cows received PGF (0.75 mg, IM) twice on the third day of the treatment, and cows were inseminated at 48 and 60 h after second PGF treatment; embryo recovery was performed 7 d later. Follicular development was monitored ultrasonically every 24 h from the first FSH treatment to ovulation, and the numbers of medium (MF, 5–8 mm) and large (LF, &gt;8 mm) sized follicles, and corpora lutea (CL) were counted on the day of embryo recovery. Estrous status was determined by walking activity of cows as an estrous index. Each cow was fitted with a pedometer (Gyuho; Comtec, Miyazaki, Japan) that measures total amount of walking activity per hour, and data of individual cows were sent to a personal computer in real time. Estrus was defined as an increase in number of steps to more than the value of mean steps plus standard deviation recorded for the preceding 240 h. Data were analyzed by one-way ANOVA. There was no significant difference among the Gel-40, Gel-30, and control groups for the mean ( � SD) duration of estrus (22.3 � 5.2 h, 18.0 � 2.8 h and 18.5 � 5.3 h, respectively), increments of estrous activity (398.3 � 135.3%, 388.9 � 44.4% and 393.9 � 82.1%, respectively), and the mean interval from the first PGF to onset of estrus (35.5 � 2.2 h, 37.8 � 5.7 h and 39.3 � 5.6 h, respectively). There was no significant difference among the Gel-40, Gel-30, and control groups for the mean number of large follicles at the time of estrus (21.3 � 10.2, 21.5 � 7.6 and 21.0 � 9.4, respectively), number of CL at the time of ova/embryo collection (21.5 � 10.2, 19.2 � 4.9, and 20.5 � 9.5, respectively), the total number of ova/embyos recovered (12.3 � 8.3, 12.5 � 7.8, and 13.8 � 9.2, respectively), or transferable embyos (3.3 � 4.8, 4.5 � 3.5, and 5.5 � 4.5, respectively). Results suggested that administration of 30 mg of FSH in 5 mL Gel by a single injection in the ischiorectal fossa was effective in inducing superstimulation in Holstein cattle. This work was supported by a grant of the Research Project for Utilizing Advanced Technology (04–1676).

Terminal follicular growth, ovulation rate and hormonal secretion after melatonin pretreatment prior to FGA-PMSG synchronisation in Suffolk ewes at the onset of the breeding season

The first experiment was performed in order to determine the effect of exogenous melatonin followed by a fluorogestone acetate (FGA) and pregnant mare's serum gonadotrophin (PMSG) treatment on terminal follicular dynamics, ovulation rate and luteinizing hormone (LH) pulsatility in Suffolk ewes at the beginning of the breeding season. Therefore, 10 ewes (MEL/FGA/PMSG) were injected melatonin 22 days before receiving sponges containing 40 mg of FGA for 14 days and 800 IU of PMSG at the removal of pessaries. Ten other ewes (FGA/PMSG) were synchronised with the same FGA/PMSG treatment without melatonin. The second experiment was undertaken to determine the effects of exogenous melatonin followed by a FGA-PMSG synchronisation on the plasma FSH, E 2 and P 4 concentrations. The investigations on terminal follicular growth and LH pulsatility were repeated. Six ewes were submitted to a MEL/FGA/PMSG treatment and six other to a FGA/PMSG control following the same design as in the first experiment. Melatonin treatment was effective in increasing ( p < 0.05) the circulating melatonin during a period of more than 14 days but was ineffective in lowering plasma PRL concentrations. LH pulsatility during and after the hormonal treatment and the concentrations of plasma FSH and P 4 were comparable among MEL/FGA/PMSG and FGA/PMSG groups. Concentrations of plasma E 2 during the luteal phase but not during the follicular phase of the synchronised estrous cycle were lower ( p < 0.05) in ewes treated with melatonin when compared to controls. The two groups differed only at the time of selection : the percentage of medium follicles undergoing atresia was lower ( p < 0.05) in the MEL/FGA/PMSG than in the FGA/PMSG (38% and 35.5% versus 65% and 61.5%); this resulted in a increased ( p < 0.05) mean number of large follicles (4.7 ± 0.5 versus 3.2 ± 0.5) and ovulation rate (2.6 ± 0.4 versus 1.45 ± 0.35).

Active immunization of cattle against partly purified follicular fluid from sheep.

Yearling cross-bred heifers were injected with 0.4 or 4 mg total protein in non-ulcerative Freund's adjuvant (Groups A and C, respectively; N = 5 per group), or adjuvant with C. parvum (Groups B and D, respectively; N = 5 per group). Control heifers were not treated (N = 9). No antibodies were detected in heifers in Groups A and C and so these were excluded from the analysis. There was no effect of the treatment on Group B or D heifers after the priming or first booster injection. After a second booster injection one Group D heifer gave a triple ovulation, and two Group D heifers and one Group B heifer gave double ovulations, but for one oestrous cycle only. Group B heifers also showed a significant rise in FSH concentrations after the second booster injection. Group D heifers were given a third booster injection; there was an increase in the mean number of large follicles per heifer, and a decrease in oestrous cycle length, but no increase in ovulation rate. These results indicate that a transient increase in ovulation rate can be induced by actively immunizing cattle against partly purified follicular fluid from sheep.

Ovarian function in Holstein cows immunized against pregnant mare serum gonadotrophin

Six Holstein-Friesian cows were immunized against pregnant mare serum gonadotrophin (PMSG) using Freunds' adjuvant during the mid-luteal phase of the estrous cycle. Antibody response was maintained by five booster immunizations at 2- to 3-wk intervals. Four cows were treated with a single intramuscular injection of PMSG (2350 I U) 107 d after primary immunization. Cloprostenol (500 ug) was administered at 56 h and 72 h after the treatment with PMSG; the cows were inseminated three times at 12-h intervals starting 56 h after cloprostenol treatment. Five days after insemination, the animals were slaughtered and their reproductive organs were recovered to quantify the population of corpora lutea and unovulated follicles (>10 mm dia). Antibody titres and progesterone concentrations were determined from blood samples collected either on alternate days or twice a week. Initially, progesterone concentrations were measured in milk samples. All cows produced antibodies, and titres were elevated within 6 to 9 d following each booster immunization. After each boost, however, the antibody titres declined rapidly. Progesterone concentrations declined to below 1 ng/ml after two weeks of initial immunization and remained low throughout the study, except in one cow that ovulated on Day 75. All animals were observed to have large follicular cysts during this period. Treatment with PMSG induced a single ovulation in one cow. Ovulations were neither induced by PMSG nor observed in any of the other animals. In PMSG-treated animals, the mean number of large follicles (5.0) was greater than in those which were not treated (2.0). The results of this study suggest that low titres of antibodies against PMSG are sufficient to disturb ovarian activity, result in follicular cysts and block multiple ovulations in response to exogenous PMSG.

Oestrous behaviour, follicular growth and ovulation during pregnancy in the hare (Lepus europaeus).

Sexual chase was observed throughout pregnancy in hares permanently housed with a male. The incidence of oestrus followed by mating increased rapidly from Day 34 to day 38. Follicular growth was not interrupted; the mean number of large follicles increased at the end of pregnancy. Ovulation could be induced by hCG at any stage of pregnancy, but only on the last days by mating.