estrus synchronization

حرية الوصول المقاله

1 - بررسی اثر هم‌زمان‌سازی فحلی و استفاده از GnRH بر برخی شاخص‌های سرمی و میزان باروری گوسفندان نژاد ماکویی در فصل تولیدمثل
رسول بابازاده اقدم غلامعلی مقدم حسین دقیق کیا سیدعباس رافت آیتک بخشایش خیابانی سینا مقدم

یکی از مهم‌ترین مشکلات دامداری ها پایین بودن نرخ باروری است. بنابراین، می توان با استفاده از هورمون های صناعی فرآیند تولیدمثل را در دام ها کنترل و نرخ باروری آن ها را با استفاده از هم زمان سازی فحلی افزایش داد. هدف از انجام این مطالعه بررسی اثر هورمون GnRH(هورمون آزادکن أکثر

یکی از مهم‌ترین مشکلات دامداری ها پایین بودن نرخ باروری است. بنابراین، می توان با استفاده از هورمون های صناعی فرآیند تولیدمثل را در دام ها کنترل و نرخ باروری آن ها را با استفاده از هم زمان سازی فحلی افزایش داد. هدف از انجام این مطالعه بررسی اثر هورمون GnRH(هورمون آزادکننده گنادوتروپین) در روزهای 10، 11 و 12 بعد از تلقیح مصنوعی بر باروری میش بود. برای این منظور 226 رأس گوسفند ماکوئی با استفاده از سیدر همزمان سازی فحلی شدند. پس از درآوردن سیدر، تمامی میش ها PMSG(گنادوتروپین سرم مادیان آبستن) را به مقدار 400 واحد بین المللی دریافت کردند. دو روز بعد، میش های فحل شده با اسپرم تازه، تلقیح مصنوعی شده و به سه گروه تقسیم شدند. گروه شاهدهیچ هورمونی دریافت نکرد. گروه دوم به زیرگروه های D، E و Fتقسیم شدند که به ترتیب در روزهای 10، 11 و 12 بعد از تلقیح مقدار 20 میکروگرم GnRH(هورمون آزادکننده گنادوتروپین‌) به روش عضلانی دریافت کردند و گروه سوم (گروه G) نیز در روز 12 بعد از تلقیح مقدار 40 میکروگرم GnRH دریافت کرد. 5 میلی لیتر خون دو روز بعد از تزریق به وسیله لوله ونوجکت گرفته شد. غلظت گلوکز، فسفر، اوره، پروتئین تام و پروژسترون سرم خون اندازه گیری گردید. برای تجزیه متغیرهای وابسته و متغیرهای مستقل به ترتیب از رویه GLM(General Linear Model) و FREQ (frequencies) نرم افزار SASاستفاده شد. نتایج نشان داد که اثر GnRH بر میزان پروژسترون کاملاً معنی دار بود (01/0>p). همچنین بیشترین نرخ باروری متعلق به گروه سوم بوده و تفاوتی معنی دار در نرخ باروری بین گروه مذکور با سایر گروه ها مشاهده شد (01/0>p). به طور کلی می توان نتیجه گرفت که تزریق 5 میلی‌لیتر GnRH در روز 12 بعد از تلقیح، نرخ باروری میش را بهبود می‌بخشد. تفاصيل المقالة

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2 - Effects of PMSG Doses on Reproductive Performance of Kurdi Ewes Artificially Inseminated during Breeding Season
M. Nosrati M. Tahmorespoor M. Vatandoost M. Behgar

This experiment was conducted to determine the reproductive performance of Kurdi ewes which were artificially inseminated (AI). In total 240 Kurdi ewes, weighing 49.5±2.5 kg were used in the trail. The ewes were allocated randomly to one of four groups (n=60/in e أکثر

This experiment was conducted to determine the reproductive performance of Kurdi ewes which were artificially inseminated (AI). In total 240 Kurdi ewes, weighing 49.5±2.5 kg were used in the trail. The ewes were allocated randomly to one of four groups (n=60/in each group). For synchronizing, controlled internal drug release (CIDR) was placed in the vagina of all individuals for 14 days. After removing the CIDR, pregnant mare's serum gonadotropin (PMSG) hormone was intramuscularly injected at the dosages of 300, 400, 500 and 600 IU in four groups of ewes. Cervical artificial insemination was performed after two days following CIDR withdrawal and hormone administration. The conception rates in groups I, II, III and IV were found as 63.7, 66.1, 65.8 and 67.9%, respectively. The mean litter size was significantly higher in groups II, III and IV (1.30, 1.34 and 1.46) than group I (1.11). The fecundity rate was lowest in group I (65.6%). Administration of 600 I.U PMSG resulted in the highest (58.9%) multiple births (P<0.05). These results suggest that 600 I.U. PMSG was more effective in increasing multiple births in the Kurdi ewes in breeding season. تفاصيل المقالة

حرية الوصول المقاله

3 - Effect of Flushed Feeding and Age on Estrus Synchronization and Conception Rate of Holstein × Local Crossbred Cows After Using Analogue GnRH and Prostaglandin F2α Hormone
M. Sydur Rahman M. Kabirul Islam Khan T. Bilkis

The study was conducted to know the effect of flushed feeding on estrus synchronization and conception rate of Holstein ÍLocal crossbred cow’s after using the GnRH (fertagyl) and PGF2α hormone. As a representative sample 20 Holstein ÍLocal cros أکثر

The study was conducted to know the effect of flushed feeding on estrus synchronization and conception rate of Holstein ÍLocal crossbred cow’s after using the GnRH (fertagyl) and PGF2α hormone. As a representative sample 20 Holstein ÍLocal crossbred cows were chosen from Chittagong Cantonment Military Dairy Farm in Bangladesh and the experimental work was carried out for 60 days. Ten cows were flushed with high energy feed (10.5 mega Joule metabolisable energy/kg feed dry matter) and considered as treated group and 10 cows was allowed for normal feeding. Both the control and treated group cows were injected intramuscularly by the GnRH and PGF2α hormone. After injection of these hormones, 100% cows from both groups showed estrus. Fixed time artificial insemination (AI) was done and the cows were diagnosed in pregnancy after 60 days of AI. It was observed that 20% cows were conceived after AI from control group, but treated group cows showed more conception / pregnancy rate (40%). After using the hormones, age of the cow did not influences for estrus synchronization, but for conception rate it was observed that younger cows showed more than older one. تفاصيل المقالة

حرية الوصول المقاله

4 - Efficacy of CIDR or FGA Sponges with hCG Treatments on the Conception Rate and Prolificacyin Lori Ewes Out of the Breeding Season
M.M. Moeini F. Alipour M.R. Sanjabi

Two experiments were performed to determine the effectiveness of different progestogens contained in intravaginal devices, different doses of eCG and subsequent hCG treatment on the reproductive performance of estrus-induced mature Lori ewes. In the first experiment, 88 أکثر

Two experiments were performed to determine the effectiveness of different progestogens contained in intravaginal devices, different doses of eCG and subsequent hCG treatment on the reproductive performance of estrus-induced mature Lori ewes. In the first experiment, 88 ewes were allocated into two groups, and were treated with either fluorogestone acetate (FGA) sponges or Controlled Internal Drug Release devices (CIDR).The sponges were withdrawn 13 days after insertion and then ewes were treated with either 350 IU or 500 IU of eCG by intramuscular injection. There was no significant difference among treatments in the percentage of ewes in estrus or the interval to the onset of estrus. However, the conception rate and prolificacy of ewes treated with 350 IU eCG, in both the FGA and CIDR groups, was higher than ewes treated with 500 IU of eCG. In the second experiment 384 ewes were randomly divided into three groups and after synchronization with FGA spongesand 350 IU of eCG, 128 ewes in the first group (T1) were injected 250 IU hCG when artificially inseminated, 128 ewes in the second group (T2) were injected 250 IU hCG 12 days after AI and the 128 ewes in the third group (C) acted as the control group. Estrous was determined by monitoring 35 teaser rams to calculate estrous rate. Prolificacy and conception rate were assessed and serum progesterone (P4) concentrations were measured on days 12, 14 and 16 days after AI. Prolificacy was increased in the T1 group compared with control group (P<0.05) and conception rates were higher in hCG treatments (P<0.05). The weight of single lambs on the day ofbirth increased with the hCG injection on days 0 and 12 (P<0.05). The P4 concentration was higher in the hCG-treated groups compared with the control ewes on day 16 (P<0.05). It is concluded that CIDR and FGA sponges were equally effective for estrous induction in anestrous Lori ewes and P4 concentrations increased with 200 IU hCG given at the time of AI or 12 days after AI which could improve reproductive performance. تفاصيل المقالة

حرية الوصول المقاله

5 - The Effect of Administering Equine Chorionic Gonadotropins (eCG) on Reproductive Performance of Dairy Cows with a CO-Synch + CIDR Protocol and Insemination at a Fixed Time
م.م. منشادی ع. رستگارنیا Sh. اسماعیلی ثانی

The success of a ﬁxed-time artiﬁcial insemination (FTAI) program depends on a high ovulation rate during a short interval. Equine chorionic gonadotropin (eCG) has been used in FTAI protocols to improve follicular growth and thereby to produce larger, more responsive fol أکثر

The success of a ﬁxed-time artiﬁcial insemination (FTAI) program depends on a high ovulation rate during a short interval. Equine chorionic gonadotropin (eCG) has been used in FTAI protocols to improve follicular growth and thereby to produce larger, more responsive follicles for ovulation with increased pregnancy rates. The aim of the present study was to evaluate the effects of eCG on conception rates of early post-partum dairy cows treated by progesterone-based estrous synchronization with artificial insemination at a fixed time (CO-Synch+CIDR protocols). 144 Holstein cows ≥ 55 days postpartum were used. All cows were enrolled in a 7-day CO-Synch + CIDR protocol which included 100 μg gonadotropin releasing hormone (GnRH) at CIDR insertion (day 0); 500 µg prostaglandin F2α (PGF2α) at CIDR removal (day 7); and 100 μg GnRH at FTAI, 66 hours after PGF2α (day 10). Cows were randomly assigned as control cows (n=69) or treated cows (n=75) which received 500 IU eCG at the time of CIDR removal. All cows were examined by ovarian ultrasound at FTAI. The addition of eCG to CO-Synch+CIDR protocols improved the frequency of estrous response (control cows 51.4%, eCG-treated cows 87.8%; P<0.01). It reduced the interval between the end of treatment and the start of estrus (control cows 56.8±5.52 hours, eCG-treated cows 45.7±5.87 hours; P<0.01). It increased dominant follicular size at FTAI (control cows 15.1±2.41 mm, eCG-treated cows 19.6±1.84 mm; P<0.001). However, eCG had no effect on pregnancy rates (control cows 49.3%, eCG-treated cows 54.6%; P=0.131). The use of eCG, prior to termination of 7-day estrus synchronization when using the CO-Synch+CIDR program alone, could hasten the time of estrous expression and should be considered in FTAI dairy cows. تفاصيل المقالة

حرية الوصول المقاله

6 - Comparison of Different Methods of Oestrus Synchronization on Reproductive Performance of Farahani Sheep in Iran
آ. میرشمس الهی

This experiment was carried out on 123 Farahani ewes from a herd in Delijan city in Markazi province of Iran to determine the best short-term method for oestrus synchronization. Ewes were divided into five experimental groups randomly: group 1) use of controlled interva أکثر

This experiment was carried out on 123 Farahani ewes from a herd in Delijan city in Markazi province of Iran to determine the best short-term method for oestrus synchronization. Ewes were divided into five experimental groups randomly: group 1) use of controlled intervaginal drug release devices (CIDR) for 7 days with intramuscular (IM) injection of PGF2α on zero day and IM injection of 500 IU equine chorionic gonadotropin (eCG) at the time of CIDR removal; group 2) use of CIDR for 7 days and IM injection of PGF2α on the 6th day and IM injection of 500 IU eCG at the time of CIDR removal; group 3) use of intravaginal sponge for 7 days with IM injection of PGF2α on zero day and IM injection of 500 IU eCG at the time of sponge removal; group 4) use of intravaginal sponge for 7 days with IM injection of PGF2α on the 6th day and IM injection of 500 IU eCG at the time of sponge removal and group 5) control, without any treatment. Results showed that parturition percentage on expected date was almost doubled in all treatment groups when compared to control group. Each treatment used for oestrus synchronization increased the percentage of twinning on expected date in comparison with control group. Obtained results indicated that the most ewes lambed on expected date after 7 day treatment with both the intra-vaginal sponge and CIDR, and had a favorable impact on fertility of ewes. تفاصيل المقالة

حرية الوصول المقاله

7 - The Effects of short and long-term progesterone treatment combined with PMSG on the fertility rate of Ghezel breed ewes during the breeding season
Ghader Najafi

10.30495/jbcvm.2021.686344

The objective of this study was to compare the efficacy of short-term and long-term progesterone treatments on the fertility rate of Ghezel breed ewes during breeding season. Forty ewes were distributed in a randomized block experimental design, where the treatments con أکثر

The objective of this study was to compare the efficacy of short-term and long-term progesterone treatments on the fertility rate of Ghezel breed ewes during breeding season. Forty ewes were distributed in a randomized block experimental design, where the treatments consisted of two protocols for estrus synchronization (short, 7 days and long, 12 days) with twenty animals each. The progesterone treatment consisted of a vaginal sponge containing 30 mg fluorogestone acetate (FGA) inserted into the vagina of the ewes for 7 or 12 days. Afterwards, on the 5th and 10th days of the protocols, 0.5 ml Clo Pg® and 400 IU of PMSG was intramuscularly administered to all the ewes. Percentage of estrous, pregnancy and lambing rates were 80%, 75% and 56.25% in the short term treated group and 95%, 84.21% and 73.68% in the long term treated group respectively. The litter size did not differ between the short term and the long term treated groups (1.44 vs. 1.50). There were no significant differences in fertility responses between protocols (P>0.05).The short-term progesterone treatment was effective to synchronize estrus in Ghezel breed ewes during breeding season. However, comparing the protocols, the long-term protocol presented better results of positive estrus percentage, pregnancy rate and lambing rate in Ghezel breed ewes تفاصيل المقالة

حرية الوصول المقاله

8 - تاثیر ملاتونین بر پارامترهای تولیدمثلی میشهای نژاد شال در خارج از فصل تولیدمثل
اکبر دودانگه جعفر یدی علی قاضی خانی شاد

به منظور بررسی تاثیر ملاتونین برپارامترهای تولیدمثلی میشهای نژادشال در خارج از فصل تولیدمثل، تعداد 60راس میش با شکم زایش1-3در4گروه در قالبطرح بلوکهای کامل تصادفی مورد مطالعه قرارگرفتند که هرگروه شامل15راس میش بود. گروه کنترل هیچگونه هورمونی دریافت نکرد. درگروه ملاتونین، أکثر

به منظور بررسی تاثیر ملاتونین برپارامترهای تولیدمثلی میشهای نژادشال در خارج از فصل تولیدمثل، تعداد 60راس میش با شکم زایش1-3در4گروه در قالبطرح بلوکهای کامل تصادفی مورد مطالعه قرارگرفتند که هرگروه شامل15راس میش بود. گروه کنترل هیچگونه هورمونی دریافت نکرد. درگروه ملاتونین،Regulinحاوی 18میلی گرم ملاتونین به مدت 35روز در قاعده گوش میشها کاشتهشد. درگروه سیدر 8روز پس از سیدرگذاری، درهنگام خروج سیدر500Iuتزریق PMSGانجام شد. گروه ملاتونین همراه سیدر 35روزپس از کاشت Regulinبه مدت 8روز سیدر گذاری شدو پس از خروج PMSG 500 iuتزریق شد. به هر 4گروه پس از مرحله هم زمانی فحلی 4راس قوچ بارور به مدت5روز اضافه گردید. همچنین 15روز بعد دوباره قوچها اضافه شدند تا درصورتی که در نوبت اول میشی آبستن نشده باشد احتمال آبستنی آن بالا رود. پس از رکورردگیری، دادهها توسط نرم افزار ،SASآنالیز شدند. مقایسه میانگینگروههای آزمایش بااستفاده ازآزمون چند دامنهای دانکن در سطح %5انجام گرفت. تعدادبرههای تولدیافته در گروه ملاتونین بالاتربود و تفاوت معنیدار باسایرگروهها داشت( .)P>0/05هیچ گونه تفاوت معنیداری در میانگین وزن بره های 4گروه وجود نداشت( .)P<0/05تعداد سرویس(جفتگیری)به ازایهرآبستنی و درصد آبستنی در گروه ملاتونین عملکرد بهتری نسبت به سایرگروهها دارد و تفاوت معنیداری از نظر آماری مشاهده شد( .)P>0/05در بررسیپارامترهای نرخ برهزایی و درصد آبستنی نیزبین گروهها تفاوت معنیدار مشاهده شد.استفاده از هورمون ملاتونین بر پارامترهای تولیدمثلی میشها در شرایط خارج فصل تولیدمثلی موثر میباشد. لذا باتوجه به کاربرد آسانتر ملاتونین کاشتنینسبت به سایر روشهای همزمانسازی فحلی و عدم آلودگی و عفونت واژن و کاهش هزینههای مدیریتی بهتراست جهت بهبود عملکرد تولید مثلی میشهااز ملاتونین کاشتنی استفاده نمود تفاصيل المقالة

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