Time Of Sponge Removal Research Articles

The effect of human menopausal gonadotropin and equine chorionic gonadotropin on the reproductive performance of treated ewes with short-term progesterone injections and sponge during the non-breeding season.

This study investigated the effect of human menopausal gonadotropin (hMG) on reproductive efficiency of synchronized ewes with the sponge and progesterone (P4) injection-based protocols. In study 1, anoestrous ewes (n = 120) were used. Sixty ewes were treated with sponge (S) for 12 days. The injection of eCG (SeCG group, n = 30) or hMG (ShMG, n = 30) was given at the time of sponge removal. Thirty ewes received IM injection of P4, three times every 48 h and the injection of hMG was given 24 h after the third P4 injection (3PhMG group, n = 30), and 30 ewes were used as control group. Pregnancy was diagnosed on day 50 after the release of ram. In study 2, 60 ewes were randomly divided into two equal groups. In the treated group with antibiotics (n = 30), before inserting, the sponges were impregnated with the antibiotic penicillin G sodium (5,000,000 IU) and in the control group (n = 30), there was no added antibiotics. Before inserting and after removing sponges, a vaginal cytology sample was taken with a sterile cotton swab. The number of neutrophils in each sample was counted and analysed. The rate of oestrus and total pregnancy was greater in SeCG (96.7, 93.3%), ShMG (82.8, 93.1%) and 3PhMG (67.9, 89.3%) groups compared with the control group (13.8, 41.4%) (p < .05). No significant difference was found in single, twin and total lambing and pregnancy rates after injection of eCG and hMG during the non-breeding season (p > .05). A higher percentage of control ewes had the vaginal smear with neutrophils more than 50% (96.7% vs. 76.7%; p < .05). In conclusion, a single dose of hMG can induce fertile oestrus in synchronized ewes with P4 administered by either injection or intravaginally. Purulent discharge and percentage of neutrophils were significantly reduced in the synchronized ewes by the impregnated sponges with the antibiotic penicillin.

Litter size affects ovulation and pregnancy rate after a hormonal treatment without influencing expression of estrus in the anestrous season in ewes

The aim of this study was to determine if litter size affects the response to hormonal treatments for inducing estrus and ovulation during the non-breeding season. A total of 124 Corriedale ewes were utilized, consisting of 56 ewes that had given birth during the spring and were currently nursing either a single lamb (Single, n = 30) or twin lambs (Twin, n = 26). Additionally, a control group of ewes that had not given birth (Con, n = 68) was included. Estrus was induced 38 days after lambing using intravaginal sponges containing medroxyprogesterone acetate, which were left in place for 7 days. Furthermore, 350 IU of eCG was administered at the time of sponge removal. Upon detection of estrus, the ewes were inseminated, and transrectal ultrasonography was performed 8 and 40 days later to determine the presence of a corpus luteum (CL) and pregnancy, respectively. Expression of estrus did not differ due to postpartum status. However, a higher proportion of Con ewes than Twin ewes had a corpus luteum (P = 0.02), while the Single group did not differ from the other groups. Conception and pregnancy rates were higher in the Con group than in both, the Single and Twin groups (P ≤ 0.03). The litter size did not have a significant effect on the estrous response; however, postpartum status and/or lactation negatively impacted the pregnancy outcome.

Evaluación del protocolo corto y largo de sincronización de celo en borregas inseminadas con semen congelado

The objective of the study was to evaluate the effect of short (5 days) and long (9 days) SC protocols in ewes inseminated with frozen semen on the diameter of the uterine horn and pregnancy rate. The experiment was carried out at the Carolina Experimental Center, belonging to the National University of the Altiplano, and 40 ewes be-tween Corriedale and Criollas were used; in groups of 20 for each treatment, which were synchronized with in-travaginal sponges based on Medroxyprogesterone acetate, for 9 days (long protocol) and 5 days (short protocol) and at the time of sponge removal, 350 IU of eCG were applied. To measure the diameter of the uterine horn, ultrasonography was performed at 36 h post sponge removal and at 56 h after cervical insemination with thawed semen and a subsequent ultrasonography at 35 days to confirm gestation. Quantitative data were analyzed using the statistical t-test for uterine horn diameter and Chi-square for gestation rate. The results for uterine horn diameter were 11.11±1.52 and 12.12±2.12 mm for the short and long synchronization protocol, respectively. Regarding the pregnancy rate, 21.05 % and 25 % were obtained for the short and long synchronization protocol, respectively. Therefore, we can conclude that the long progesterone treatment had better results than the short treatment both in uterine diameter and pregnancy rate, but this difference was not significant (p>0.05).

Comparison of Pregnancy Rates after Short - Term and Long -Term Synchronization Protocol in Ewes- Pilot Study

The objective of the study was to compare the pregnancy rates after short-term and long-term synchroniza-tion protocol in Kivircik ewes. Ewes (n=54) were randomly divided into two synchronization groups as ST (short-term; n=27) or LT (long-term, n=27). Intravaginal sponge was inserted on the same day (D0) in both groups. It was removed at 7 days (D7) in the ST group and 13 days (D13) in the LT group. All ewes received 450 IU eCG and 75 μg d-cloprostenol at the time of sponge removal. The characteristics of vaginal discharge were evaluated following sponge withdrawal. For both protocols, 5 fertile rams per 27 ewes were used for natural mating following sponge removal. The overall estrous response and pregnancy rate were 88.9% and 64.8%, respectively. Following the synchronization, the overall estrous response (94.7% vs. 85.7%, respectively) and pregnancy rate (63.1% vs. 65.7%, respectively) were similar in both multiparous and nulliparous ewes. Although the short-term protocol reduced the rate of severe vaginitis from 48.1% to 25.9%, pregnancy rates were not different in both synchronization protocols. Nulliparous ewes had a higher rate (48.6% vs. 15.8%) of severe vaginal discharge than multiparous ewes. However, the alteration of the vagi-nal discharge severity depending on parity did not affect the overall pregnancy rate after the short-term (66.7%) and long-term (63.0%) protocols. Therefore, the long-term and short-term protocol can be used in both nulliparous and multiparous ewes in small flocks.

Effects of vitamin B1, vitamin E and selenium on pregnancy and blood metabolites profile during non-breeding season and early prediction of pregnancy by thermographic monitoring in Merino ewes

The objective of this study was to evaluate the effects of injectable selenium, vitamin E and vitamin B1 compounds on serum metabolic profile and pregnancy rates (PR) during the non-breeding season in Merino ewes that were synchronized with progesterone and equine chorionic gonadotrophin (eCG). Thermographic monitoring of ewes on the last day of synchronization was successful in the early selection of ewes to be used in artificial insemination and its relationship with pregnancy outcomes. Cyclic and non-pregnant ewes (n=75) were randomly assigned to treatment (n=30) and control (n=45) groups. All animals were synchronized using PGF2α at day 0, progesterone impregnated intravaginal sponges for 14 days, eCG 48 h before sponge withdrawal and artificial insemination were carried out 43–45 h after sponge removal. Animals of treatment group (n=30) were administered (intramuscularly) with 1 mg sodium selenite, 60 mg vitamin E and 40 mg vitamin B1 on two occasions, at the beginning of sponge insertion and following sponge removal. Blood samples were collected at sponge insertion and removal. Perianal and perivulvar areas were considered to evaluate the thermal pattern at day 0 and 14 using a thermo camera. Overall, 90.6% of ewes exhibited estrus in response to the synchronization protocol. Ewes of treatment group showed greater PR as compared to that of control group (70.3% vs 56%). Perivulvar temperature was influenced by time only. At the time of sponge removal, perivulvar temperatures were significantly lower in pregnant ewes than in non-pregnant animals. In conclusion, injectable selenium, vitamin E and vitamin B1 compounds increased PR after synchronization protocol and thermographic evaluation that was performed on the last day of synchronization could be used for very early prediction of pregnancy.

Influence of Different Synchronization Protocols on Fertility Response in Surti Does

This study was carried out to assess the influence of different estrus synchronization Protocols on fertility response in Surti does based on litter size, fecundity and twining rate. Thirty does were selected and divided into five equal groups (n=6 in each). Does of G1 group were treated with intra-vaginal progestagen sponges (IVPS) for 11 days. Does of G2 group received the same IVPS sponge for 11 days and exposure of sexually active apronized buck during the treatment period. Does of G3 group were treated as per G1 group along with i/m injection of PGF2andalpha; analog (125 µg, Cloprostenol) at the time of sponge removal. Does of G4 group were subjected to the buck effect and exposed to a sexually active patronized buck for 11 days, and does of G5 group was kept as a control without any treatment for 11 days. It was found that, none of the synchronization Protocols had significant effect on litter size, fecundity, and incidence of multiple kid birth and sex ratio in Surti does.

Addition of eCG to a 14 d prostaglandin treatment regimen in sheep FTAI programs

In the present study, there was evaluation of the alternative of adding eCG as part of a long-interval prostaglandin-F2α (PG) treatment on the reproductive efficiency of Merino sheep during the breeding season. A total of 210 ewes and 182 ewe lambs were randomly assigned to three experimental groups to induce the timing of estrus among ewes in a: Long-interval PG, group being synchronized using two doses of PG 14 days apart; Long-interval PG + eCG group being synchronized using the same treatment regimen as Group PG with the addition of 200 IU eCG to the regimen, administered concomitantly with the second PG administration; and MAP + eCG group being synchronized with intravaginal progestin sponges for 14 days plus 200 IU eCG, administered at the time of sponge removal. The percentage pregnancy rate in ewes of the MAP + eCG group was greater than the ewes of the Long-interval PG and Long-interval PG + eCG groups (76.4 % compared with 52.0 % and 62.5 %, respectively; P < 0.05). The prolificacy rate was greater in the ewes of the Long-interval PG+eCG group compared with the other groups (114 % compared with 100 % and 103 %, respectively; P < 0.05). When considering the fecundity rate, ewes of the Long-interval PG+eCG and MAP+eCG groups had greater values than ewes of the Long-interval PG group (71.2 % and 78.8 % compared with 52.0 %, respectively; P < 0.05). The Long-interval PG+eCG is an alternative to the conventional progestin sponge plus eCG treatment regimen with there being a greater fecundity rate when this regimen is used compared with the Long-term PG and similar to MAP-eCG treatment regimens.

Ovarian activity in dairy Saanen goats subjected to a short-term ovulation induction protocol and a single injection of lecirelin (GnRH analog) given 28 h or 34 h after progestin pre-treatment

Abstract Fixed-time artificial insemination (FTAI) and hormonal superovulation (SOV) are instrumental in enhancing genetic gain and productivity of commercial goat herds. The goal of this study was to document changes in antral follicle populations and ovulation in dairy Saanen does. Fifty-six animals received MAP sponges that were left in place for 6 days as well as 200 IU of eCG and 120 μg of cloprostenol i.m. 24 h before sponge withdrawal. Does were randomly divided into three groups: Gcon (n = 18) received 1 mL of saline 28 h after, whereas G28h (n = 19) and G34h (n = 19) received 25 μg of lecirelin i.m. 28 h or 34 h after sponge removal. Estrus was detected with intact bucks every 12 h and transrectal ovarian ultrasonography was carried out from the time of sponge removal until ovulation detection (8/8 h – 60 h after sponge removal) and then until 156 h after sponge withdrawal (12/12 h). There were no differences (P > 0.05) among GnRH-treated and control goats in estrus responses (G28h–57.9%; G34h–84.2%; Gcon–83.3%) and mean ovulation rates (G28h–100%; G34h–91.7%; Gcon–81.8%), but the intervals from MAP sponge withdrawal to ovulation and from the estrus onset to ovulation were less variable (P

Effect of different short term synchronization protocols on estrus and fertility in non-pregnant ewes during the breeding season

The aim of this study was to investigate the efficacy of different short term synchronization protocols on estrus and pregnancy rates in merino ewes that had not become pregnant after at least three matings during the breeding season. Three different protocols were used as follows: Group I: Ewes (n=30) were inserted intravaginal progesterone sponge (florogestan asetate; 30 mg) for 6 days plus PGF2α (125 μg, i.m.) at the time of sponge removal, Group II: Ewes (40) were treated same as in group 1 plus eCG (250 IU, i.m.) at time of sponge removal, and Group III: Ewes (n=38) were only injected with PGF2α at the same time with the ewes in the other two groups. Estrus was detected by rams (n=4), 24 hours after PGF2α and ewes detected in estrus were mated. Ten rams were used for mating. Pregnancy was diagnosed 60 days after mating by ultrasonography. Estrus, conception and pregnancy rates were: for Group I 100%, 73.3% and 73.3%, for Group II 92.5%, 89.2% and 82.5% and for Group III 81.6%, 100% and 81%. In Group III, pregnancy loss after pregnancy diagnosis was significantly higher (35.4%) compared with the other groups (Group I: 13.6% and Group II: 15%).

Gonadotrophin stimulation of ewes that are not pregnant following multiple matings during the season

In this study, the aim was to obtain pregnancy following synchronization and to increase profitability in ewes that did not become pregnant during the breeding season after at least 3 matings. Nonpregnant Middle Anatolian Merino ewes (n = 117) were given a progesterone sponge for 9 days. At the time of sponge removal, the ewes received 250 IU pregnant mare serum gonadotropin (PMSG) + 125 µg prostaglandin F2α (PGF2α). Two days later, they were injected with either human chorionic gonadotropin (hCG) (Group I, n = 48) or gonadotropin-releasing hormone (GnRH) (Group II, n = 43), or remained as a control (Group III, n = 26). The ewes were allowed to mate at estrus following the PGF2α injection. Pregnancy diagnosis was performed on day 30 after mating by ultrasonography. Group ratios for estrus (58.3%, 55.8%, 53.8%), conception (78.6%, 87.5%, 14.3%), lambing (90.9%, 90.5%, 50.0%), multiple births (15.0%, 31.6%, 0.0%), and average lamb number for birth (1.15%, 1.31%, 1.0%) were reported. In conclusion, the gonadotropin-supplemented protocols used here were found to be useful in ewes that were not pregnant after multiple matings during the breeding season in increasing the profitability of flocks with this problem.

Evidence of a molecular clock in the ovine ovary and the influence of photoperiod

The influence of the central circadian clock on reproductive timing is well established. Much less is known about the role of peripheral oscillators such as those in the ovary. We investigated the influence of photoperiod and timing of the LH surge on expression of circadian clock genes and genes involved in steroidogenesis in ovine ovarian stroma. Seventy-two Suffolk cross ewes were divided into two groups, and their estrous cycles were synchronized. Progestagen sponge removal was staggered by 12 hours between the groups such that expected LH peak would occur midway through either the light or dark phase of the photoperiodic cycle. Four animals from each group were killed, and their ovaries were harvested beginning 36 hours after sponge removal, at 6-hour intervals for 48 hours. Blood was sampled every 3 hours for the period 24 to 48 hours after sponge removal to detect the LH surge. The interval to peak LH did not differ between the groups (36.2 ± 1.2 and 35.6 ± 1.1 hours, respectively). There was an interaction between group and the time of sponge removal on the expression of the core clock genes ARNTL, PER1, CRY1, CLOCK, and DBP (P < 0.01, P < 0.05, P < 0.01, P < 0.01, and P < 0.01, respectively). As no significant interaction between group and time of day was detected, the datasets were combined. Statistically significant rhythmic oscillation was observed for ARNTL, CLOCK, CRY1 (P < 0.01, respectively), PTGS2, DBP, PTGER2, and CYP17A1 (P < 0.05, respectively), confirming the existence of a time-sensitive functionality within the ovary, which may influence steroidogenesis and is independent of the ovulatory cycle.

Determination of the proper time for mating after oestrous synchronisation during anoestrous or oestrous by measuring electrical resistance of cervical mucus in ewes

The purpose of the present study was to investigate whether the electrical resistance values of the cer - vical mucus and/or blood οestradiol-17β and progesterone concentrations at mating, after oestrous synchronisation during the anoestrous or oestrous period in ewes, are related to fertility. Oestrus was induced by medroxyprogesterone acetate-impregnated intravaginal sponges (Veramix, Upjohn, USA), either for 12 days (12-day group; 24 Kymi and 28 Chios) or for 14 days (14-day group; 24 Kymi and 28 Chios), plus 400 IU equine chorionic gonadotropin (Intergonan, Intervet, the Netherlands) i.m., at the time of sponge removal. In each case, one blood sample was collected from all ewes at sponge insertion, at sponge removal and at oestrus, for the determination of serum οestradiol-17β and progesterone concentrations, using a radioimmunoassay. The electrical resistance of the cervical mucus was meas - ured once, just after oestrus detection by teaser rams, using a digital heat detector. All ewes found to be in oestrus were mated to fertile rams. Pregnancy was determined by transabdominal ultrasonography 35-40 days after mating. Kymi ewes were in anoestrous, while those of Chios were in the oestrous period. The 14-day treatment resulted in better outcome as concerns oestrus detection and pregnancy rate than the 12-day treatment, in either oestrous or anoestrous period ewes. Oestradiol-17β concentrations at sponge removal and at oestrus were lower ( P < 0.05) in the 14-day group than in the 12-day group, in both oestrous or anoestrous period ewes. Progesterone concentrations at sponge insertion and removal were higher ( P < 0.05), while progesterone concentrations and electrical resistance values of the cervical mucus at oestrus were lower ( P < 0.05) in ewes of both groups who conceived compared to those that did not, either in oestrous or in the anoestrous period. Linear regression analysis revealed a positive relation between the electrical resistance values of the cervical mucus and blood serum progesterone concentrations in both oestrous or anoestrous period ewes. The electrical resistance of cervical mucus could be useful for the detection of the proper time for mating after oestrous synchronisation in ewes.

Sensitivity, specificity, predictive value and accuracy of ultrasonography in pregnancy rate prediction in Sahelian goats after progesterone impregnated sponge synchronization

Aim: This study was aimed to evaluate the sensitivity, specificity, predictive value and accuracy of ultrasonography in pregnancy rate (PR) prediction in Sahelian goats after progesterone impregnated sponge synchronization within the framework of caprine artificial insemination (AI) program in Fatick (Senegal). Materials and Methods: Of 193 candidate goats in AI program, 167 were selected (day 50) in six villages. Estrus was synchronized by progesterone impregnated sponges installed for 11 days. Two days before the time of sponge removal (day 4), each goat was treated with 500 IU of equine chorionic gonadotropin and 50 μg of dcloprostenol. All goats were inseminated (day 0) with alpine goat semen from France at 45±3 h after sponge removal (day 2). Real-time B-mode ultrasonography was performed at day 50, day 13, day 0, day 40 and day 60 post-AI. Results: Selection rate, estrus response rate, AI rate, PR at days 40 and days 60 were 86.53%; 71.85%; 83.34%; 51% and 68% (p<0.05) respectively. Value of sensitivity, specificity, positive and negative predictive value, accuracy, total conformity, conformity of correct positive, conformity of correct negative and discordance of pregnancy diagnosis by trans-abdominal ultrasonography (TU) were 98.03%; 63.26%; 73.52%; 3.12%; 81%; 81%; 50%; 31% and 19%, respectively. Conclusion: These results indicate that the TU can be performed in goats under traditional condition and emphasized the importance of re-examination of goats with negative or doubtful TU diagnoses performed at day 40 post-AI.

Geçiş Döneminde Laktasyondaki Kıl Keçilerinde Kısa ve Uzun Süreli Progestagen Uygulamalarıyla Sabit Zamanlı Suni Tohumlamayla Birlikte GnRH Kullanımının Fertilite Parametreleri Üzerine Etkisi

Summary The aim of this study was to determine the efficiency of the progestagen containing intravaginal sponges used for 6 or 12 days at timed artificial insemination (TAI) in Hair Goats during the transition period, the effect of GnRH administrations at the time of TAI on fertility was also investigated. In this study 104 lactating hair goats aged between 2-5 years old minimally primiparous was used as animal materials. All of the goats received 30 mg fluorogestone acetate (FGA) impregnated vaginal sponges. The sponges were inserted into vagina for 6 days in the short-term (ST, n=52) group also for 12 days in the long-term (LT, n=52) group. The goats received 400 IU PMSG and 0.075 mg of cloprostenol at the time of sponge removal. The goats in both the ST and LT groups timed artificially inseminated 48 h after sponge withdrawal with fresh cooled semen. At the time of artificial insemination, the subgroups ST1 (n=24) and LT1 (n=22) were maintained as controls, the subgroups ST2 (n=24) and LT2 (n=23) received 5 mcg of buserelin acetate. Pregnancy and twinning rates of the ST1, ST2, LT1 and LT2 groups were 37.5%, 41.6%, 40.9%, 47.8% and 22%, 30%, 11%, 18%, respectively. The litter sizes were 122%, 130%,111% and 118% in the ST1, ST2, LT1 and LT2 groups, respectively. The parturition rates were 100% in all treatment groups. Pregnancy rates, twinning rates and litter sizes were not statistically different among the groups (P>0.05). The results of this study indicated that, a TAI protocol without detection estrus seems to be a suitable administration for short and long progesterone sponges aplications in lactating hair goats during the transition period. In addition, progesteron and AI without estrus detection procedure may be useful alternative to traditional synchronization program using progesteron and AI after estrus detection. Also, GnRH addition to progesterone sponges did not improve reproductive paramaters.

Oestrus synchronization with short-term and long-term progestagen treatments in goats: the use of GnRH prior to short-term progestagen treatment

The aim of the present study was to determine the efficacy of the synchronization of oestrus using short- and long-term progestagen treatments in Hair goats at the onset of the breeding season, and to evaluate the effect of the exogenous GnRH administration immediately prior to short-term progestagen treatment on the reproductive performance. A total of 75 Hair goats, aged 2.5–5 years-old were used in this experiment. Goats were divided equally into three groups (n=25 per group). Animals in LT-FGA (long-term progestagen treatment), ST-FGA (short-term progestagen treatment) and Gn-ST-FGA (GnRH-short-term progestagen treatment) groups received an intravaginal sponge (day 0) containing 30 mg fluorogestone acetate (FGA) for 14, 8 and 8 days, respectively, plus 75 µg cloprostenol i.m. 24 h before sponge removal and 400 I.U. equine chorionic gonadotrophin (eCG) i.m. at the time of sponge removal. In addition, the goats in the Gn-ST-FGA group received 10.5 µg busereline acetate i.m. at the time of sponge insertion (day 0). Oestrus response for all treatment groups was 100%. The mean interval from sponge removal and the onset of oestrus for the LT-FGA, ST-FGA and Gn-ST-FGA groups was 28.0±1.0 h, 28.8±1.1 h and 33.1±2.0 h, respectively. No significant difference in onset of oestrus among groups was recorded. The pregnancy rate, kidding rate, multiple kidding rates and litter size were 72.0, 61.1, 45.5% and 1.6 in the LT-FGA, 70.8, 76.5, 69.2% and 1.8 in the ST-FGA and 58.3, 78.6, 63.6% and 1.6 in the Gn-ST-FGA groups, respectively. The pregnancy rates were similar in the LT-FGA (72.0%) and ST-FGA (70.8%). However, the kidding rate, multiple kidding rates and litter size were numerically higher in the ST-FGA (76.5%, 69.2% and 1.8, respectively) group than in the LT-FGA (61.1%, 45.5% and 1.6, respectively) group. Although not statistically different, pregnancy rate and litter size was lower in the Gn-ST-FGA group (58.3% and 1.6, respectively) compared with the ST-FGA (70.8% and 1.8, respectively).In conclusion, it can be said that oestrus synhcronization with long-term progestagen treatment (14 d-FGA- PGF2α- eCG) could be replaced with short-term progestagen treatment (8 d-FGA-PGF2α- eCG) without a reduction in oestrus rate and fertility parameters in lactating goats at the beginning of breeding season. However, the use of GnRH prior to short-term progestagen treatment (8 d-FGA-PGF2α- eCG) do not have a positive effect on fertility parameters in goats.

Relationships of changes in ultrasonographic image attributes to ovulatory and steroidogenic capacity of large antral follicles in sheep

Ovarian steroidogenesis and antral follicular development in ewes, following the treatment with medroxyprogesterone acetate (MAP) and equine chorionic gonadotrophin (eCG), are affected by the reproductive season. The objective of this study was to compare the ultrasonographic attributes of large antral follicles between cyclic (December) and seasonally anovular (June–July) ewes, after a 12-day treatment with MAP-soaked intravaginal sponges, with or without the administration of 500 IU of eCG at sponge removal, and to determine whether there is a correlation between the ultrasonographic attributes of the follicular wall and serum concentrations of oestradiol. Digital images of ovulatory follicles from cyclic ewes and eCG-treated anoestrous ewes ( n = 34 follicles), and of anovulatory follicles attaining ≥5 mm in control anoestrous ewes ( n = 8 follicles), were analysed using the spot and line techniques designed to determine the echotextural characteristics of the follicular antrum (central and peripheral), follicular wall and perifollicular ovarian stroma. The mean diameter of ovulatory follicles was greater ( P < 0.001) in cyclic than anoestrous ewes, with or without the eCG treatment. The mean pixel heterogeneity (SD of numerical pixel values) of the follicular antrum ( P < 0.05), as well as mean pixel intensity and heterogeneity of the peripheral antrum, follicular wall proper and perifollicular ovarian stroma ( P < 0.05), were consistently greater in anoestrous than cyclic ewes at the time of sponge removal and 24 h after the treatment with MAP sponges or MAP/eCG. Mean oestradiol concentrations were greater ( P < 0.05) in cyclic compared to anoestrous ewes in both MAP- and MAP/eCG-treated animals, from 1 to 2 days after sponge withdrawal. There was a moderate negative correlation ( r 2 = 0.12, P < 0.05; Pearson's Product Moment and r 2 = 0.23, P < 0.05; ANCOVA) between mean pixel heterogeneity (standard deviation of mean pixel values) of the follicular wall proper (all follicles ≥5 mm in diameter) and serum concentrations of oestradiol after sponge withdrawal. Our results indicate that large antral follicles from cyclic and seasonally anovular ewes exhibit distinctive ultrasonographic characteristics. The differences in follicular echotexture appear to be related mainly to seasonal variations in ovarian follicular morphology and oestradiol production.

Effect of Different Doses PMSG on Estrus Synchronization and Fertility in Awassi Ewes Synchronized with Progesterone During the Transition Period

Summary The aim of the present study was to evaluate different of doses PMSG on estrus synchronization and fertility in Awassi ewes synchronized with progesterone during The transition period. A total of 92 ewes were used in this experiment. All ewes were treated with a vaginal sponge containing 30 mg fl uorogestone acetate (FGA) inserted into the vagina of the ewes for 12 days. All animals were divided into four groups randomly and a single intramuscular (IM) dose of PMSG (group 1, 300 IU, n=21; group 2, 400 IU, n=27; group 3, 500 IU, n= 25), group 4 (n=19) was injected with 1 ml normal saline solution and as served control group at time of sponge removal. The interval between the withdrawal of the sponges and estrus was observed 40.82±1.21 h, 40.20±1.14 h, 38.7±1.07 h and 41.79±1.72 h in groups 1, 2, 3 and the control group, respectively. Estrus responses were similar in all groups (group 1, 81.0%; group 2, 92.6%; group 3, 92.0%; control group, 73.78%). There were no statistically signifi cant differences (P>0.05) between the treatment groups and the control group for the onset of estrus or estrus response. The duration of estrus was shorter in group 1, compared to the control group (24.9±0.85 hr vs. 29.07±1.31hr), and that this difference was statistically signifi cant (P<0.05). Pregnancy rates were 82.35%, 80.0%, 82.60% and 78.5% in groups 1, 2, 3 and the control group, respectively. Lambing rates were obtained 100.0% among all the groups, or litter size (1.07 to 1.21) did not differ between the treatment groups and the control group. As a result, different doses of PMSG in Awassi ewes synchronized with progesterone during the transition period had similar effect on estrus synchronization and fertility parameters.

Fixed-time artificial insemination in red deer ( Cervus elaphus) in Argentina

Synchronization of estrous and fixed-time artificial insemination (FTAI) was conducted during the reproductive season of 2008 (March–April) in a local red deer breeding farm in Argentina. Multiparous suckling hinds ( n = 38) were artificially inseminated following hormonal treatment (intravaginal sponge containing 100 mg of medroxiprogesterone acetate). At the time of sponge removal (day 12) 250 IU of eCG and 500 μg of PGF2α were given to each hind. The FTAI was performed at 48–55 h after device removal with cryopreserved semen imported from New Zealand. Rectal-transcervical AI method (similar to that in cattle) was performed and semen was deposited within the uterine body ( n = 28) or the cervix ( n = 10). Pregnancy was diagnosed by means of ultrasonography 44 days after FTAI. The overall pregnancy rate was 36.8% (14/38). Percentage of does that became pregnant with intrauterine seminal deposition was 42.9% (12/28) whereas pregnancy rate in the hinds with intracervical AI was 20% (2/10; P = 0.27).

The effect of vitamin E treatment during preovulatory period on reproductive performance of goats following estrous synchronization using intravaginal sponges

The objectives of this study were to investigate whether the use of intravaginal sponge for estrous synchronization of goats causes oxidative stress, and to examine the effect of administering vitamin E during preovulatory period on reproductive performance of estrous synchronized goats. Estrus was synchronized in 36 non-lactating adult does using intravaginal sponges containing 30 mg of fluorogestane acetate (FGA) for 14 days. All females received 500 IU of eCG at the sponge withdrawal. The goats were allocated at random to two groups balanced for breed, age and body weight. Treatment group ( n = 18) received 200 mg of vitamin E i.m. at the time of sponge removal and again at the time of second artificial insemination. The other 18 goats (control) were administered 1 ml of physiological saline instead of vitamin E on each of these two occasions. All does in estrus was intracervically inseminated at 12 and 24 h after the onset of estrus. Blood samples were collected every 72 h during the experimental period for evaluation of malondialdehyde (MDA) and vitamin E concentrations. Serum MDA level increased and vitamin E concentration decreased during the period of vaginal sponge application. Following the sponge removal, MDA level declined rapidly to below basal level in the treatment group but remained high in the control group. Conversely, vitamin E concentration increased in the treatment group after the sponge withdrawal and remained at a low level in the control group. No statistically significant differences ( P > 0.05) were observed between groups in terms of estrous response, conception rate, gestation length or kidding rate. However, the number of multiple births (70.0% versus 50.0%) and prolificacy rate (2.40 ± 0.37 versus 1.63 ± 0.26 kids per kidding) were significantly higher ( P < 0.05) for the treatment group than those of the control group. The results indicate that the use of intravaginal sponges for estrous synchronization of goats causes an increase in level of oxidative stress. However, the vitamin E treatment during preovulatory period can prevent the overproduction of reactive oxygen species (ROS), and it may improve the multiple birth rates and the number of kids born in estrous synchronized goats.

The effect of estrus synchronization treatments on somatic cell count of transitional-anestrus Awassi ewes’ milk

Fifty-three transitional-anestrus Awassi ewes, randomly assigned to three groups: fluorogestone acetate (FGA, n = 18), FGA-Prostaglandin (FGA-PGF, n = 18) and control (n = 17), were used to examine the effect of estrus synchronization protocols and steroid hormones concentrations on milk somatic cell count (SCC). Intravaginal FGA sponge was inserted for 13 days and 600 IU equine chorionic gonadotropin was administered for ewes of FGA and FGA-PGF groups at the time of sponge removal (day 0). In addition, 10 mg was administered to ewes of FGA-PGF group on day 0. Blood and milk samples were collected from all ewes on days -13, -6, 0, 1, 2, 7 and 14. Estradiol had significant positive correlation with the SCC during the periods of sponge insertion (P = 0.015, r = 0.235) and within two days (P = 0.063 r = 0.23) after sponge removal with no correlation with SCC of both udder halves during the luteal phase. Progesterone concentrations, on the other hand, had a significant positive correlation (P < 0.001; r = 0.420) with the SCC of both udder halves during the luteal phase of the experiment, but not during the periods of sponge insertion and expected estrus. SCC returned under the influence of endogenous progesterone on days 7 and 14 to pre-synchronization values. In conclusion, sheep milk SCC is affected significantly with induction of estrus and steroid hormones concentrations. However, peak SCC recorded during estrus was far below the upper limit of the current standard for normal milk. With the current standards for SCC of 1,000,000/ml as legal limit for abnormal milk control programs in sheep, estrus synchronization programs and the estrus status should not be considered when bulk-tank milk SCC is being investigated, but should be considered during the process of setting new standards.