The objective of this study was to evaluate three methods of estrous synchronization, viz. controlled internal drug releasing device (CIDR), intravaginal sponges impregnated with fluogestone acetate (FGA), and cloprostenol (Estrumate; an analogue of prostaglandin F2a) in Nadooshani goats of Yazd province, Iran. The estrous synchronized does (n = 30 to 33 per treatment), after heat detection, were artificially inseminated (once) with diluted semen of fertile bucks. Pregnancy was determined by measuring blood serum progesterone levels on day 21 after insemination, followed by ultrasonography at mid-gestation. No significant difference was observed for the interval between the end of the synchronization protocol and the standing heat amongst treatments (range: 23 to 35 hrs). There was no significant difference in the interval between the time of standing heat and insemination among treatments (range: 15 to 27 hrs). Blood serum progesterone levels (overall mean: 4.80 ± 0.41 ng/ml; SEM), litter size (overall mean: 1.32 ± 0.05; SEM), non-return rate to estrus and the kidding rate were not significantly affected by the synchronization methods. Serum progesterone levels were significantly lower (P<0.01) in does that returned to estrus after artificial insemination (AI). Prolificacy and fecundity were not significantly affected by the synchronization methods; however, cloprostenol method was found to be more convenient and economical under the conditions of this experiment.

The increase of reproduction performance is one of the critical factors for improving economic achievement and sustaining small and middle scale livestock producing. For this to happen, participatory research and extension programs should be implemented with the help of livestock producers. In the present study, the knowledge and attitudes of target livestock producers of ewe estrous synchronization model plan in Markazi (N=11) and Fars (N=12) provinces were investigated. The data were collected using questionnaires and in-depth interviews. The results indicated that producers obtained an average score in the knowledge test. The respondents’ attitudes towards the technology were positive. The main factors preventing the technology to be extended among neighbourhood livestock producers included: lack of attention to some of the advices (e.g., small number of rams when mating, and inappropriate feeding), not providing educational programs by organizers, lack of appropriate indicators to choose target producers, and lack of a complementary and tuned relations between educational programs and practice.

The aim of this study was investigated the effect of synchronization with different PMSG dosages and time of hormone injection and its effect on changes in steroid hormones (E2 and P4) in Farahani ewes breed. Seventy Farahani ewes used in this study. Treatment included: T1: injection of 400 IU PMSG 24h before CIDR removal, T2: injection of 500 IU PMSG 24h before CIDR removal, T3: injection of 600 IU PMSG 24h before CIDR removal, T4: injection of 400 IU PMSG in CIDR removal time, T5: injection of 500 IU PMSG in CIDR removal time, T6: injection of 600 IU PMSG in CIDR removal time, Control: no injection in CIDR removal time. After withdrawal CIDR, estrous percentage, pregnancy rate and parturition assessed. The results of this experiment showed that the conception rate was similar in all groups and there was no significant effect in lamb weight among all treatments. The number of lamb per ewe was significant between T2 and others groups (P˂ 0. 05). The progesterone levels were significantly (P<0. 01) increased from day 0 to day 50. Higher progesterone levels were recorded in all groups of ewes and non-significant between groups. In general, administration 500 IU of PMSG 24 hours before CIDR removal improved estrous percentage, pregnancy rate and parturition in ewes.

Estrus synchronization is an important technique in management of reproductive function in ewes. The objective of this study was to evaluate the effect of using combination of PMSG and GnRH hormones on estrus synchronization during the breeding season in Farahani ewes. Forty mature Farahani ewes, weighting 48. 97± 0. 55 kg, BCS 3. 04± 0. 3, were used in this study. The experimental ewes were synchronized using CIDR for a period of 10 days and injected 2 ml PGF2α at day 0 and these ewes randomly assigned to four groups. The control group (group 1; n=10) did not receive any treatment. Ewes in group 2 were injected with 150 IU PMSG and 1 ml Buserellin acetate after CIDR removal. The group 3 ewes injected with 100 IU PMSG and 2 ml Buserellin acetate after CIDR removal. The group 4 of ewes were injected with 300 IU PMSG and 0. 5 ml Buserellin acetate after CIDR removal. Estrus detected after CIDR removal, then, the ewes were mated with Farahani rams. After parturition, the reproductive parameters of ewes were recorded. The estrus rate was constant in all groups. The lamb weight in group 4 was significantly different (P>0. 05) compared with other groups. Pregnancy rate was not significantly meaningful among treatments. The lowest glucose and progesteron concentration was achieved in group 4 that was significantly different (P > 0. 05) compared to other groups. The data of birth weight also didn’ t show significant differences (P>0. 05) between the treatment groups. There was no significant difference in abortion and stillbirths between treatments (P˃ 0. 05). The results showed that the combination of two PMSG and GnRH hormones in the estrus synchronization program could increase the lambing rate up to 0. 7.

Estrous synchronization is a valuable management tool that has been employed successfully in enhancing reproductive efficiency, particularly in cows, ewes and does (Kusina et al., 2000). Oestrous synchronization in small ruminants is achieved either by reducing the length of the luteal phase of the oestrous cycle with prostaglandin F2α or by artificially extending it with exogenous progesterone or potent progestagens A completely randomized design experiment was carried out using eighty Zel ewes during out of season breeding to compare different dosage of equine chorionic gonadotrophin (eCG) with controlled internal drug release (CIDR) dispensers to synchronize estrous. Intravaginal progestagen was administered for a 13-day period. Upon progestagen withdrawal, doses received 350, 400, 450 and 500 IU (eCG) intramuscularly. Teaser rams (1/8 ewes) were introduced 1 d after treatment removal to detect estrus. Ewes were subjected to fertile rams 40 h after CIDR removal. The results of this experiment showed that eCG was effective when used with CIDR. Different dosage of eCG treatments had not significant effect on estrus response (100% in all groups). Enhancing the level of eCG administration led to a increase in fecundity rate and lambing rate in this study.In conclusion the CIDR device with 450 and 500 IU can improve reproductive performance in Zel ewes comparable to 350 and 400 IU eCG.

It seems that; long exposure to equine chorionic gonadotropin (eCG) in ewe synchronization programs would stimulate the growth of ovarian follicles resulting in better reproductive performance. Therefore, the aim of present study was to expose Farahani ewes to longer duration of eCG by using an eCG-alhydrogel mixture as a slow-release eCG. Fifty Farahani ewes (3-4 years, 44 ± 1.3 kg BW, BCS 3.04±0.3 on scale 1 to 5) were treated with controlled internal drug release (CIDR) for 14 days. The experimental groups consisted of: control group receiving no eCG, and four groups of ewes receiving either 400 IU eCG or eCG-alhydrogel preparation (i.m.) at 24 h (-24S, and -24SR groups, respectively), or 48 h (-48S and -48SR groups, respectively) prior to CIDR removal. Blood samples were taken from two days before until one day after CIDR removal. Reproductive performance was recorded at lambing. There was no difference (P>0.05) between groups in terms of the pregnancy rate, lambing rate, fertility, multiple birth and fecundity. However orthogonal contrasts showed that the fecundity and multiple birth were higher (p <0.05) in eCG-alhydrogel ewes. In all groups, estradiol concentration showed an increasing trend with time (p <0.05). Estradiol concentration was significantly higher in the -48SR compared with the -48S group; no difference was observed between 24S and -24SR ewes (P>0.05). The findings indicated that in an estrous synchronization protocol, administration of slow- release eCG preparations might improve the fecundity and multiple births in sheep. Keywords: alhydrogel, estrous synchronization, Farahani ewe, reproductive performance

Superovulatory response of Garganica and Maltese goats to FSH-P was studied during anestrus period. We chose 40 goats from two different breed and divided into 4 equal groups. Groups 1 and 2 consist of Garganica breed (n=20) and groups 3 and 4 consist of Maltese breed (n=20). Progestagen intravaginal sponge (FGA) was used for groups 1, 3 and 4 for 18 days. Group 2 received the same treatment but only for 11 days, plus prostaglandin analogue (ICI) was administered on the 10th day. The FSH-P was administered in steps, 7 injections (72 hours) for groups 1, 2, 3 and 4 injections (36 hours) for group 4. The first injection was given 48 hr (groups 1, 2, 3) and 24 hr (group 4) before the sponge removal animals were mated. Embryo recovery was done 7 days after the sponge removal. The results showed that the time of estrous was significantly more synchronized in groups 2 vs 1 and 4 vs 3. Significant differences were found in the ova recovery of group 3 vs groups 1 and 4 (81.1 vs 59.4, 46.9, p < 0.01); ova fertilized of 1 vs 3 (77.3 vs 61.1, P < 0.05); viable embryos of 1 vs 3 and 2 (84.3 vs 56.4, 67.2, P<0.05). The yield of viable embryos tended to be higher in Garganica goats with the treatment of FGA+ PG and with 7 injections of FSH-P.

This study aims to investigate the impact of modern management practices on reproduction and pregnancy in crossbred dairy goats (Boer×Local). The goats were maintained at the Mountain Research Centre for Sheep and Goats at the State Agricultural University to develop a dairy goat breed suitable for the climatic conditions and local needs. This research focuses on the effects of estrous synchronization and artificial insemination (AI) on pregnancy rates. In this study, 20 female goats were divided into two groups. Group I was treated with cloprostenol (125 µg) for estrous synchronization, and estrous signs were observed over the course of one week. In Group II, a buck goat was used as a biological stimulator for estrous detection and synchronization (buck effect). Estrous signs were recorded. For AI, frozen semen was obtained from the Maharashtra Goat and Sheep Research and Development Institute in India. Insemination was performed twice at 12 h intervals, and only semen with over 60% progressive motility was used. Pregnancy detection was conducted using ultrasonography and kidding records. Pregnancy was confirmed via transabdominal ultrasound on day 25 post-mating, and goats were re-examined on day 60 of pregnancy to check for fetal viability. The results indicated that estrous synchronization and AI significantly affected pregnancy rates and reproductive quality. This research will assist farmers and researchers in improving management prac-tices in dairy goat reproduction and emphasizes the necessity of employing scientific and modern tech-niques in the livestock industry.

This study presents a meta-analysis comparing the effectiveness of short-term and long-term progesterone-based protocols for estrous synchronization in sheep, focusing on pregnancy rates. The primary aim was to evaluate whether short-term protocols, which are more practical, yield comparable results to traditional long-term methods in terms of pregnancy success. The study is based on a meta-analysis of 22 independent studies conducted between 2010 and 2023, which examined various progesterone-based estrous synchronization protocols in different seasons. The data was collected from Scopus, PubMed, OpenAlex, and Google Scholar databases using keywords such as "progesterone", "P4", "estrous”, “synchronization, " "sheep, " and "ewe. " The results revealed no significant difference between short-term and long-term protocols concerning pregnancy rates. This suggests that both protocols are equally effective, with short-term protocols offering logistical and cost benefits. However, the analysis also highlighted moderate heterogeneity among the studies, indicating that factors like breed, nutrition, and environment might influence outcomes. This meta-analysis provides valuable results into the effectiveness of short-term versus long-term progesterone-based estrous synchronization protocols in sheep. The findings indicate that short-term protocols are just as effective as long-term protocols in achieving pregnancy, offering significant advantages in terms of cost and labor efficiency.  Additionally, potential publication bias was identified, underscoring the need for further research in this area to refine these reproductive strategies.