Dose Of Cloprostenol Research Articles

INDUCTION OF PARTURITION IN A PYGMY HIPPOPOTAMUS (CHOEROPSIS LIBERIENSIS).

A 27-yr-old female pygmy hippopotamus (Choeropsis liberiensis) had two consecutive stillbirths with no overt signs of labor, suggestive of uterine inertia. After a third pregnancy was confirmed, an induction protocol was developed. Cloprostenol and betamethasone were administered on d 200 of gestation (time 0 h). Additional doses of cloprostenol were administered at 24 and 48 h and oxytocin at 30, 31, and 48 h. Each injection resulted in preparturient behavior without overt evidence of contractions. Fetal membranes presented at the vulva at 54.5 h after initial cloprostenol and betamethasone administration with no progression of labor. Transvaginal palpation and manual delivery of a live calf followed. Despite confirmed nursing, the serum glutaraldehyde coagulation test was negative. Failure of passive transfer may have been secondary to the induction protocol. The calf was treated with broad-spectrum antimicrobial agents due to diarrhea, and clinical signs resolved. This clinical brief details the first known induction of parturition in a pygmy hippopotamus, which can serve as the basis for further development of the technique.

The male effect associated with prostaglandins and reproductive outcomes in photo‐stimulated Saanen goats during the non‐breeding season

AbstractThe efficiency of combining oestrous induction via a light program (16 h of light and 8 h of darkness for 60 days, ending on Day 0 – D0) with cloprostenol administration, followed by the male effect or not, was tested in acyclic Saanen goats during the non‐breeding season (June/2019 to January/2020). Initially, all animals (males and females) were submitted to the described light program; 60 days after its ending (D60), the females were divided into two groups, with (G1; n = 67) or without (G2; n = 61) a male effect from D60 to D75 after the light program. At D75, both groups received two cloprostenol doses (120 μg; intramuscular) 7.5 days apart (D75 and D82.5). Artificial insemination was performed at a specific time according to the oestrous onset (approximately 68.4 ± 1.2 h between the second cloprostenol dose and IA). Ultrasound scans were performed at different intervals to evaluate follicular dynamics and confirm pregnancy. At the first cloprostenol dose (D75), the proportion of does with at least a corpus luteum (CL), which indicates resumed cyclicity, was greater in G1 than in G2 (85.2% vs. 48.8%; p < .05), although no difference was found at the second dose (p > .05). The adjusted pregnancy rates (number of pregnant goats/oestrous goats) differed between G1 and G2 (21.7% vs. 42.0%; p < .05). G1 also showed a higher frequency of functional CL (based on blood flow and morphology) compared to G2 (96.9% vs. 66.7%; p < .05) at D116. A male effect using photo‐stimulated bucks after the first cloprostenol dose increased the number of does presenting CL after buck removal, and no impairment in the pregnancy rates of multiparous does was found.

Customized modified therapies for ovarian cyst and persistent follicle followed with TAI in early postpartum dairy cows.

Postpartum ovarian dysfunction [ovarian cyst (OC) and persistent follicle (PF)] has been an important issue. Finding effective hormonal treatments to improve reproductive performance in dairy cows has become a necessity. Improve reproductive performance and ovarian activity in postpartum cows with specific customized treatment for OC and PFs. The study included 48 cows at 14 days P.P, which received two dosages of 500 μg IM cloprostenol, 14 days apart as presynchronization protocol. Ultrasound ovarian scans 14 days after the last injection for 4 weeks. The cows were divided into three groups according to ovarian status: OC (n = 14), PF (n = 12), and NE (n = 22). In the OC group, received 500 μg IM cloprostenol and 100 μg IM cystoriline, a second dose of cloprostenol 14 days later and a second dose of cystoriline 36 hours later, and AI after 24 hours (GnRH+ PG/PG/GnRH). In the PF group, was fitted with progesterone-releasing intravaginal device (PRID) for 9 days; the same day, they received 100 μg cystoreline then 500 μg cloprostenol 7 days later, after PRID removal AI 56 hours later (PRID + GnRH/PG). In the NE group, artificial insemination was implemented until 28 days depending on estrus detection. The ovarian activity was greatly affected by the customized treatments, leading to enhanced follicular and luteal activity, particularly after the PGF2α injection. The OC and PF groups showed substantial estrus responses of 71.43% and 75.02%, respectively, during AI time. While the NE group had an ovulation rate of 54.5% and a pregnancy rate of 31.8%, the treatment groups showed marked improvements in reproductive performance. The ovulation rates in the OC and PF groups were 71.43% and 75% and the pregnancy rates at the 1st artificial insemination were 64.28% and 66.7%. Improving reproductive performance and minimizing the time to first service are possible advantages of early case-specific treatment for postpartum cows with OC and PFs.

Luteal tissue blood flow and side effects of horse-recommended luteolytic doses of dinoprost and cloprostenol in donkeys

This study assessed luteolysis and side effects in jennies receiving standard horse-recommended doses of cloprostenol and dinoprost. Sixteen cycles of eight jennies were randomly assigned in a sequential crossover design to receive dinoprost (5 mg, i.m.) and cloprostenol (0.25 mg, i.m.) at 5-d post-ovulation. B-mode and Doppler ultrasonography were employed to assess luteal tissue size and blood flow before (-15 min and 0h) and after (0.5, 1, 2, 3, 4, 5, 6, 7, 8, 12, 24, and 48h) administering PGF2α. Immunoreactive progesterone concentrations were assayed at similar timepoints via RIA. Side effects such as sweating, abdominal discomfort, and diarrhea were scored at 15-min-intervals for 1h after PGF2α. Data normality was assessed with the Shapiro-Wilk's test. Luteal tissue size and blood flow were analyzed using PROC-MIXED and post-hoc by Tukey. Non-parametric tests analyzed side effect variables. The luteal blood flow increased overtime by 27% at 45 min and peaked by 49% at 3 h for dinoprost, and conversely, it increased by 14% at 30 min and peaked at 39% at 5h for cloprostenol (P<0.05). Luteal blood flow was reduced by 50%, 25%, and 10% on both groups at 8, 12, and 24h (P<0.05). Immunoreactive progesterone concentrations decreased in 0.5h for dinoprost and 1h for cloprostenol and gradually decreased by 48h (P<0.05). Dinoprost induced greater sudoresis scores, while cloprostenol resulted in greater abdominal discomfort and diarrhea scores (P<0.05). In conclusion, dinoprost and cloprostenol effectively induced luteolysis with distinct side effects; this could guide practitioners’ case selection to use one or another PGF2α.

CASE REPORT: A SUCCESSFUL TREATMENT STRATEGY FOR CYSTIC OVARIAN DISEASE IN A DAIRY COW

A 5-year-old multiparous lactating Holstein cow was reported to have cystic ovarian disease with a history of whitish vaginal discharge on the 80th day postpartum. On the 83rd day postpartum, transrectal ultrasonography revealed a thick-walled cystic structure with visible cobwebs in the cavity, measuring 4.2[Formula: see text]cm × 3.4[Formula: see text]cm in diameter on the right ovary. The serum progesterone (P4) concentration was 6.82[Formula: see text]ng/mL, leading to a diagnosis of luteinized follicular cyst. Transvaginal aspiration of the cyst was performed to decrease the compression of ovarian stroma by the cyst, followed by intramuscular administrations of cloprostenol and buserelin. A 1.9[Formula: see text]cm diameter corpus luteum was detected on the right ovary nine days after aspiration, with a serum P4 concentration of 1.29[Formula: see text]ng/mL. Continual hormone treatment was followed, consisting of an injection of buserelin and an intravaginal progesterone-releasing device inserted for seven days. After seven days, two corpora lutea were noted on the right ovary with an average diameter of 2.8[Formula: see text]cm and 1.8[Formula: see text]cm, respectively. The device was removed and the cow showed a P4 concentration of 11.22[Formula: see text]ng/mL on that day. Estrus induction was conducted with two low doses of cloprostenol followed by an injection of gonadorelin, to induce a complete luteolysis and the following ovulation to fit a fixed-timed artificial insemination (AI). Pregnancy was confirmed 33 days after AI. Although the number of days open was 102 in this case, it took a total of 19 days from treatment to pregnancy.

Recombinant equine FSH superovulation in the mare

Inducing ovulation of multiple follicles has been an elusive goal in equine reproduction. Administration of porcine FSH, ovine FSH or GnRH agonists only yield a marginal increase in ovulation rate in mares. Early studies utilizing single chain recombinant equine FSH (reFSH) reported stimulation of follicular development in anestrous mares and increased ovulation rates in cycling mares. Unfortunately, the original reFSH product from AspenBio Pharma, Inc. (Castle Rock, CO USA) is no longer in production. The goal of the current study was to evaluate the efficacy of a new single chain recombinant equine FSH (reFSH-FP; FertilPlus Partners, LLC; Conroe, TX USA) in stimulation of follicular development in mares in two pilot studies as compared to the original reFSH (reFSH-AB; AspenBio Pharma). Study 1. Nine seasonally anestrous mares (follicle diameter 19 ± 3.7 mm) were randomly assigned to one of 3 treatment groups (n=3/group): saline placebo, reFSH-AB (0.65 mg, IM, q12), reFSH-FP (0.65 mg, IM, q 12h) for a maximum of 7 days. A dose of hCG (2,500 units, IV) was administered after a 36-hour coast period once one or more follicles attained a diameter of ≥ 35 mm. The ovulation rates for the three treatment groups were 0, 10.3 ± 3.5, and 6.0 ± 2.0 ovulations for the saline placebo, reFSH-AB and reFSH-FP, respectively. Study 2. Twelve normally cycling mares were randomly assigned to one ofthe same treatment protocols as described for Study 1 above (n=4 per group). All mares were in mid-diestrus at the onset of treatment and a dose of cloprostenol (250 µg, IM) was administered on the second day of treatment. Mares were treated for a maximum of 7 days. HCG (2,500 units, IV) was administered after a coast period of 36 hours when one or more follicles attained a diameter of ≥ 35 mm. Ovulation rates were 1.3 ± 0.5, 5.5 ± 5.3, and 5.3 ± 1.0 ovulations for the saline placebo, reFSH-AB and reFSH-FP, respectively. All mares ovulated in the placebo and reFSH-FP groups after administration of hCG; one mare in the reFSH-AB group developed 12 follicles > 35 mm in diameter, but failed to ovulate after administration of hCG. Collectively, these studies confirm that the new recombinant equine FSH product (reFSH-FB; FertilPlus) has biological activity in the mare similar to that of the original reFSH product (reFSH-AB; AspenBio Pharma) and is capable of stimulating development of multiple large follicles in deep anestrus and cycling mares. However, significant hurdles remain before a recombinant equine FSH product could be available for commercial production, distribution and clinical use. Additional research will be needed to evaluate safety, dosage, frequency of administration, timing of administration of an ovulation induction agent, and fertility following reFSH treatment.

Effect of cloprostenol on luteolysis in jennies

An intensive farm system has progressively emerged with the rapid development of the donkey industry. One of the primary challenges impeding the development of the donkey industry and the preservation of endangered donkey species is the low reproductive efficiency of jennies (Feng Yang et.al. Equine Veterinary Journal 2021, 53: 1218-1226). In donkeys, luteolysis occurs between days 15 and 17 after ovulation (Carluccio A. et.al. Theriogenology, 2007, 68(6): 914-919). To shorten the estrus cycle, a new estrus cycle may start after luteolysis is induced by the PGF2α analog (Duccio P. et.al. Theriogenology, 2018, 121: 175-180). Treatment of mares and cattle with PGF2α analogs from the fifth day after ovulation induces luteolysis (Bergfelt DR. et.al. Theriogenology, 2006, 65(8): 1605-1619). However, information regarding luteolysis in jennies is limited. In this study, we aimed to investigate the effect of cloprostenol on luteolysis in jennies. The PGF2α analog used in the experiment was cloprostenol (0.2 mg/2 ml, Ningbo Second Hormone Factory, Zhejiang, China). To study the effects of different cloprostenol doses on the estrus cycle, jennies were treated with 0.2 mg (n=30), 0.4 mg (n=30), or 0.6 mg (n=30)cloprostenol (PGF2α), respectively. The time of luteolysis, ovulation interval, follicular size at ovulation, and ovulation rates were compared between the groups. The results showed that luteolysis rates in the jennies within 72 h of treatment were higher than 90% in the three treatment groups. The time required for luteolysis was not statistically different among the three groups. In addition, the estrus interval, ovulation interval, ovulation diameter, and ovulation rate did not differ among the three groups. To examine the timing effect of cloprostenol treatment on the estrus cycle, jennies were treated with 0.4 mg cloprostenol on the third (D 3, n=30), fifth (D 5, n=30), or seventh (D 7, n=30) day following ovulation, respectively. The results showed that the luteal phase of the D 3 treatment group was shorter than that of the D 5 and D 7 treatment groups, and in the D 5 treatment group was shorter than that of the D 7 group (P < 0.05). In can be concluded that treatment with 0.4 mg cloprostenol on the third day following ovulation shortens the length of the luteal phase and estrus cycle considerably.

Effect of cloprostenol on luteolysis and comparison of different estrus synchronization protocols in jennies

Estrus synchronization is necessary for intensive donkey farming. Studies on estrus synchronization in jennies are, however, scarce. We aimed to investigate the susceptibility of the donkey corpus luteum to cloprostenol and design a successful estrus synchronization protocol. Firstly, the effects of different cloprostenol doses and the timing effect of cloprostenol treatment on estrous cycle was investigated. The time from treatment to luteolysis, the ovulation interval, pre-ovulatory diameter, and ovulation rates were compared between groups. Secondly, to identify the best protocol, eight estrus synchronization protocols from three categories were examined. In the first category, jennies in groups A (n = 55) and B (n = 30) received a progesterone releasing intra-vaginal device (JVID®) and cloprostenol treatment. In the second category (group C to F), jennies were pretreated with deslorelin, and then treated with JVID and cloprostenol, including groups C (n = 50), D (n = 50), E (n = 70), and F (n = 65). In the third category, jennies were treated with deslorelin and cloprostenol, including groups G (n = 40) and H (n = 40). Comparisons were made among groups regarding the degree of synchronization, ovulation, and pregnancy rates. Treatment with 0.4 mg cloprostenol on the third day following ovulation minimized the length of the luteal phase and estrous cycle. Synchronization rate varied from 60.0% to 88.6% among groups and was highest in group E. Pregnancy rates did not differ among the eight protocols. In conclusion, cloprostenol effectively induced luteolysis in jennies and a treatment protocol combining deslorelin, cloprostenol, and JVID is efficient for estrus synchronization in donkeys.

Effects of farrowing induction using cloprostenol on sow farrowing characteristics.

Background and Aim:Previous findings regarding the effects of farrowing induction on the farrowing characteristics of sows are controversial. This study aimed to investigate the effects of farrowing induction on the following characteristics: (1) Proportion of sows that farrowed during working hours, (2) stillbirth rate, (3) number of stillbirths per farrow, (4) dystocia rate per farrow, (5) dystocia rate (the proportion of farrowings that had at least one dystocia event), (6) number of dystocia events per farrow, (6) farrowing duration, (7) birth interval, and (8) birth weight.Materials and Methods:Thirty-eight Landrace x Yorkshire sows were randomly allocated into two groups; the control group and the treatment group. In the control group (n = 18), sows farrowed spontaneously. In the treatment group (n = 20), farrowing was induced approximately 2 days earlier than the herd’s average length of gestation (7:00 am on day 114) by injecting cloprostenol into the perivulval region. All sows were supervised throughout their farrowing. We recorded the interval between induction and farrowing; total number of births; number of live, stillborn, and mummified piglet births; number of dystocia events; birth interval; farrowing duration; and birth weight. A generalized linear mixed model, a linear mixed-effects model, the Chi-squared test, and Student’s t-test were used to compare outcomes between the two groups.Results:Farrowing induction did not influence the percentage of sows that farrowed during working hours (7 am–5 pm), stillbirth rate, birth weight, and number of dystocia events per farrow. Farrowing induction led to an increase in birth interval, dystocia rate, dystocia per farrow (p < 0.05) and in addition to the percentage of sows that farrowed on the day following induction (60% vs. 27.8%; p < 0.05).Conclusion:Farrowing induction using a single dose of cloprostenol 2 days before the expected farrowing date can be performed with care to concentrate farrowing into a short interval. This can enhance the optimization of cross-fostering and the practice of an all-in-all-out strategy in the swine breeding industry.

Use of two cloprostenol administrations 11.5days apart efficiently synchronizes oestrus in photostimulated multiparous dairy goats in the non-breeding season.

This study assessed the efficiency of synchronous oestrous induction by light programme followed by two doses of cloprostenol in acyclic Saanen goats of different parity orders. Primiparous (n=22) and multiparous (n=33) goats were subjected to 16hr of light and 8hr of darkness for 60days (D0-D60), starting 10days after the winter solstice. All goats received 120µg cloprostenol doses on D130 (morning) and D141.5 (afternoon) (11.5days apart). Oestrus behaviour, ovarian follicular dynamics and serum progesterone (P4) analyses were recorded from D0 to D174 at different intervals. Animals in oestrus after D141.5 were randomly assigned into two groups: assisted natural mating (NM) or artificial insemination (AI; 10-24hr after oestrus onset with frozen-thawed semen). From D57 to D120, 89.0% of goats presented large follicles (5-8mm) and P4 concentrations were subluteal from D0 to D120. More multiparous compared to primiparous goats (54.5%, 18/33 vs. 18.2%, 4/22) exhibited oestrus after both injections. More primiparous compared to multiparous goats (54.5%, 12/22 vs. 12.1%, 4/33) did not exhibit oestrus after any injection. A total of 35 goats (64%) were in oestrus after the second prostaglandin injection and were subjected to NM or AI. The conception rate was similar among primiparous (70.0%, 7/10) and multiparous (68.0%, 17/25) goats but the pregnancy rate differed, being 31.8% (7/22) and 51.5% (17/33), respectively. No interaction was found between parity order and P4 concentrations in does that became pregnant or not. Thus, the association between light programme (60days, starting at the beginning of winter) and two cloprostenol administrations 11.5days apart (starting 70days after the end of the light treatment) resulted in sufficient synchronous oestrous response in multiparous acyclic Saanen goats to reach satisfactory fertility levels after both NM and AI.

Responses to intra-luteal administration of cloprostenol in dairy cows

The aim of the study was to determine the luteolytic dose of cloprostenol administered directly into the corpus luteum (CL; intra-luteal treatment, ILT) in dairy cattle. Cows of two control groups were treated with 500 μg of cloprostenol (Estrumate®) intramuscularly (IM-500) or via ILT with 0.2 mL of physiological solution (ILT-0). Cows of four experimental groups were treated by ILT with cloprostenol in doses 5, 25, 50 and 100 μg (ILT-5, -25, -50 and -100 groups). Progesterone concentrations (P4) and size of CL were evaluated to assess luteolysis at 0, 0.5, 1, 2, 4, 8, 24 and 48 h or at 0, 24 and 48 h after ILT, respectively. Cows in the ILT-0 and -5 groups were unaffected by ILT. The P4 concentrations were less in cows of the IM-500, as well as ILT-25, -50 and -100 groups at 48 h subsequent to ILT. The size of the CL was less in cows of IM-500, as well as ILT-25, -50 and -100 groups at 48 h after ILT. There were P4 concentrations of about 1 ng/mL 48 h after ILT in cows of the IM-500, as well as ILT-50 and -100 groups. In conclusion, the cloprostenol dose of 50 μg administered intra-luteally is a luteolytic dose in cows.

1,2, 2, 3, 2, 1,4*

1,2, 2, 3, 2, 1,4*

Ultrasound guided diagnosis of anoestrus and its treatment in postpartum crossbred Holstein-Friesian cows

This study was undertaken to determine the feasibility of using ultrasonography for diagnosis of postpartum anoestrus followed by its effective management and treatment in crossbred (Holstein-Friesian X zebu) cows. A total of 57 crossbred lactating cows with unobserved oestrus for ≥60 days postpartum was examined by ultrasonography at Central Cattle Breeding and Dairy Farm (CCBDF), Savar, Dhaka. Cows were divided into silent oestrus and true anoestrus groups by ultrasonography. The pregnancy was diagnosed transrectally using ultrasonography 28 - 35 days after AI. Cows with silent oestrus were treated with Cloprostenol (500 μg) followed by AI or with 2 doses of Cloprostenol 10 days apart followed by AI at observed oestrus. The true anoestrus cows were supplied with anthelmintic and vitamin ADE injection with balanced nutrition, treated with Gonadorelin (500 μg) followed by AI or with Gonadorelin followed by injecting Cloprostenol at 7 days interval and AI at observed oestrus. All cows with silent oestrus and true anoestrus were divided into different body condition score (BCS), milk yield, age and parity groups to determine their influence on outcome of treatment. Out of 57 anoestrus cows examined, 56% were confirmed as silent oestrus and 44% were confirmed as true anoestrus. In silent oestrus, 71% cows showed cyclicity and 43% became pregnant after treatment with Cloprostenol and 78% cows showed cyclicity and 50% became pregnant after treatment with 2 doses of Cloprostenol 10 days interval (P&gt;0.05). In true anoestrus group, 60% cows showed cyclicity and 40% became pregnant when balanced diet was supplemented. Around 78% cows showed cyclicity and 44% became pregnant after treatment with Gonadorelin and 91% cows showed cyclicity and 55% became pregnant when Gonadorelin was followed by Cloprostenol at 7 days interval (P&gt;0.05). Significant (P&lt;0.05) influence of parity was observed in post-treatment cyclicity in true anoestrus cows. The Bangladesh Veterinarian (2019) 36(1 - 2): 33-41

161 Increasing the dose of cloprostenol sodium reduced pregnancy losses but did not increase pregnancies per AI in lactating dairy cows

Incomplete luteolysis after last prostaglandin F2α (PGF2α) of Ovsynch in fertility programmes decreases the likelihood of pregnancy per AI (P/AI) in lactating dairy cows (Martins et al. 2011 J. Dairy Sci. 94, 2815-2824; https://doi.org/10.3168/jds.2010-3652). Two doses of PGF2α 24h apart increased the percentage of cows with complete luteolysis (Brusveen et al. 2009 J. Dairy Sci. 92, 1412-1422; https://doi.org/10.3168/jds.2008-1289). Increasing the dose of cloprostenol sodium (CLO) from 0.5 to 0.75mg enhanced luteolytic properties and increased P/AI (Giordano et al. 2013 Theriogenology 80, 773-783; https://doi.org/10.1016/j.theriogenology.2013.07.003). We hypothesised that a 1.0-mg dose of CLO would not have different P/AI compared with two 0.5-mg doses 24h apart but would have greater P/AI than a single dose (0.5mg) in a timed AI programme. We also hypothesised that dose of CLO would not affect pregnancy losses. The objective was to determine the effect of cloprostenol dose on P/AI and pregnancy losses in lactating dairy cows. Lactating dairy cows (n=944) were randomly assigned to three treatments of various CLO doses at final PGF2α of Ovsynch: single dose (0.5 mg; n=338), two doses 24h apart (0.5mg each; n=311), or double dose (1.0 mg; n=295). Cows were randomly assigned to treatments by parity, synchronisation status, and type of AI (Double-Ovsynch (n=546) for first AI or GGPG (GnRH-GnRH-PGF2α-GnRH; n=398) for second and third AI). Cows were classified as either synchronised or non-synchronised based on evaluation of follicle and corpora lutea (CL) development during synchronisation protocols using ultrasound. Synchronised cows were defined as having at least one Day 7 and Day 14 CL at time of treatment. About 72% of all cows were classified as synchronised. Synchrony was not different between treatments. Within-cow pregnancy-specific protein B levels on Days 17 and 24 post-AI were used to determine pregnancy at 24 days. Pregnancy was confirmed via ultrasonography 34 days post-AI. All binomial variables were analysed using chi-square with PROC FREQ in SAS (SAS Institute Inc.). There were no differences between treatments on P/AI on d 24 post-AI (55, 50, and 53% for 0.5mg, two doses of 0.5mg 24h apart, and 1.0mg, respectively; P=0.35). At 24 days post-AI, P/AI were greater in synchronised versus non-synchronised cows (57 vs. 42%; P&amp;lt;0.0001). Older cows (third parity or greater) had reduced P/AI (44%) compared with first-parity (60%) and second-parity (54%) cows at 24 days post-AI (P=0.0001). At 24 days post-AI, P/AI in cows inseminated following Double-Ovsynch were greater than those in cows that were resynchronised using GGPG (58 vs. 46%; P=0.0001). Pregnancy loss between 24 and 34 days post-AI was greater for cows receiving 0.5mg (single dose) versus two 0.5-mg doses 24h apart or 1.0mg (12, 6, and 5%, respectively; P=0.02). In summary, cows receiving a double dose (1.0mg) of CLO had similar P/AI to cows receiving two doses of 0.5mg 24h apart. Unexpectedly, P/AI at 24 days post-AI in cows from the single-dose group were not different from those of cows treated with a double dose and two doses 24h apart. Despite numerically higher P/AI, cows that received a single dose had greater pregnancy loss between 24 and 34 days post-AI. Further analyses of effects of treatment on luteal function assessed with colour Doppler may provide information about fertility outcomes.

Comparison between the 5-day cosynch and 7-day estradiol-based protocols for synchronization of ovulation and timed artificial insemination in suckled BOS taurus BEEF cows

The objective was to compare pregnancy per AI and follicular dynamic in suckled Bos taurus beef cows treated with either a 7-day progesterone + estradiol-based protocol or a 5-day progesterone CoSynch protocol for timed artificial insemination (TAI) during four breeding seasons. We hypothesized that estrous cycle status, days postpartum (DPP), fat depth and plasma progesterone concentration differentially modify the effect of treatments. Every year, 9 days before initiation of each breeding season, cows were randomly assigned to one of two groups. Cows in the 7-d P + E group (n = 428) received a progesterone intravaginal device (DIB) and estradiol benzoate on Day −9. On Day −2 the device was removed, and cows received cloprostenol and estradiol cypionate. Forty-eight hours later (Day 0) cows received TAI. Cows in the 5-d P + CoS group (n = 428) received a DIB, and GnRH on Day −8. On Day −3, the device was removed, and cows received cloprostenol. A second dose of cloprostenol was given on Day −2. Cows received GnRH and TAI 72 h after device removal (Day 0). On Day −9, estrous cycle status was determined. In a subset of cows (n = 79) the size of the dominant follicle was determined between Days −2 and 0. In another subset of cows (n = 340), DPP, fat depth (mm) and plasma progesterone concentration (ng/mL) were evaluated on Day −9. Pregnancy per AI was determined 30 d after TAI. Pregnancy per AI was greater for cows in the 5-d P + CoS group than for cows in the 7-d P + E group (50.9% vs. 41.3%, P = 0.01) and was also greater in cyclic than in anestrus cows (54.3% vs. 33.2%, P < 0.0001). There was also a significant effect of breeding season (P = 0.0002) and sire (P = 0.03), and an interaction between treatment group and breeding season (P = 0.03). The dominant follicle was larger (P < 0.0001) in cows in the 5-d P + CoS group than the 7-d P + E group (10.7 ± 0.29 mm vs. 9.0 ± 0.28 mm). Pregnancy per AI was greater in cows with ≥55 DPP (47.0% vs. 29.6%, P = 0.001), fat depth ≥0.50 mm (44.7% vs. 29.7%), and with plasma progesterone concentration ≥1 ng/mL (47.2% vs. 28.7%, P = 0.01). In cows with plasma progesterone ≥1 ng/mL on Day −9, pregnancy per AI was greater in the 5-d P + CoS group (60.5%) than in the 7-d P + E group (34.9%), but there was no difference between treatment groups in cows with plasma progesterone < 1 ng/mL (P = 0.07). In conclusion, the 5-d P + CoS protocol resulted in greater size of the dominant follicle and pregnancy per AI in suckled Bos taurus beef cows subjected to TAI.

Pregnancy rate in indigenous ewes by direct transfer of vitrified embryos

The effects of PMSG on superovulation, quality of embryos, and pregnancy rate were studied following transfer of vitrified embryos into indigenous ewes. Three donor and nine recipient ewes were synchronized using two intramuscular doses of Cloprostenol (PGF2α) equivalent to 125 μg Prostaglandin F2α (Ovoprost® Bayer, New Zealand) at an interval of nine days. To ensure ovulation donor and recipient ewes were treated with 600 iu and 250 iu Pregnant Mare Serum Gonadotrophin (PMSG; Folligon®, Intervet, Boxmeer, The Netherlands) at the time of 2nd injection of Prostaglandin F2α. All donor ewes were mated by fertile rams. Embryos were collected from donor ewes on day six after mating by inguinal laparotomy. Grade 1 embryos were vitrified using standard procedure. After thawing the embryos were transferred into the exteriorized uterine horn of the recipient by inguinal laparotomy. Pregnancy diagnosis was performed by trans-abdominal ultrasonography on Day 40 of transfer. Oestrus occurred 31.3 ± 8.1 hours after second injection of prostaglandin and 32.6 ± 8.7 hours in recipients. Oestrus lasted 24.7 ± 9.9 hours in donors and 32.8 ± 12.8 hours in recipients. The mean numbers of corpora lutea and embryos of donor ewes were 11.7 ± 4.0 and 8 ± 2.6, respectively. Total embryo recovery rate of donor ewes was 68.6%. The mean values of qualities of embryo yield of donor ewes were 6 ± 1.7 grade 1, 0.3 ± 0.6 grade 2, 1.3 ± 1.2 grade 3, and 0.3 ± 0.6 grade 4. Twenty embryos were vitrified, 16 embryos were transferred and four recipient ewes were found pregnant. The pregnancy rate of recipient ewes was 44.4%.Bangl. vet. 2017. Vol. 34, No. 1, 27-33

Use of two doses of cloprostenol in different intervals for estrus synchronization in hair sheep under tropical conditions.

This study evaluated the effect of two doses of prostaglandin at different intervals on reproductive parameters of crossbred ewes. In Experiment 1, 30 ewes received two doses of 120μg cloprostenol at 7 (G 7days), 9 (G 9days), or 11.5 (G 11.5days) days apart. Ultrasound assessments were performed from the first and second cloprostenol administration for 5days or ovulation detection. Estrus signs were checked by a teaser male. Plasma progesterone concentration was measured before each cloprostenol dose. In Experiment 2, 95 ewes were allocated into the same treatments and after the second dose, ewes in estrus were mated. At 30days after breeding, pregnancy diagnosis was conducted and prolificacy was evaluated at lambing. In Experiment 1, at the first cloprostenol administration, 50% of ewes had an active CL and all showed estrus. At the second administration, 66.7% of ewes had an active CL and one did not present estrus. There was no difference (P>0.05) after the second dose for as follows: overall estrous response (90%), interval from cloprostenol administration to estrous onset (42.0±4.9h), estrus duration (31.5±2.1h), ovulation rate (100.0%), and number of ovulations (1.5±0.3). In Experiment 2, both pregnancy and prolificacy rates were similar (P>0.05) for G 7days (73.3; 145%), G 9days (75.9; 125%), or G 11.5days (75.9; 145%), leading to an overall pregnancy rate of 75.0% (66/88) and prolificacy rate of 137%. Therefore, the three treatments proposed were able to promote high pregnancy and prolificacy rates in crossbred ewes.

Luteolytic efficiency of reduced doses of cloprostenol in the ewe. Effect of progesterone concentrations at the time of treatment

Seventy six ewes were treated with 7.5, 12.5, 25 or 50μg of cloprostenol on day 6 or 9 post-estrus to compare the luteolytic efficiency of the PGF2α analogue at each stage and to evaluate if progesterone concentrations at the time of treatment affect such efficiency. Blood samples were obtained before cloprostenol administration and 12, 24, 48, and 72h thereafter. There was an effect of dose (p<0.05) but not of day post-estrus on the proportion of animals completing luteolysis. As the dose increased, the proportion of ewes completing luteolysis also increased. Also, as the dose increased from 7.5 to 25μg, more ewes showed a transient progesterone decline instead of an absence of response, indicating that in some ewes reduced doses initiated luteolysis but were not able to finish the process. Since the dose of 25μg resulted in close to 50% luteolytic efficacy, this group was used to study the effects of progesterone concentrations at the time of treatment on the response to cloprostenol. Pre-treatment progesterone concentrations were higher (p<0.01) in ewes experiencing luteolytic failure than in those that completed luteolysis. There was a negative correlation between initial progesterone concentrations and their reduction by 12h post-treatment. It is concluded that high progesterone concentrations are associated with a reduction in sensitivity to small doses of cloprostenol. Possible mechanisms and implications of this luteoprotective effect are discussed.

Effects of cloprostenol and flurogestone acetate sponge on embryo yields and quality in indigenous ewes in Bangladesh

The effects of two doses of cloprostenol and two doses of flurogestone acetate sponge on the onset of oestrus, and embryo recovery and quality were evaluated. Thirty-two indigenous ewes (Wera breed) were allocated into four groups of eight. All ewes were synchronised with 100 µg (Group I) or 175 µg (Group II) cloprostenol injection, 9 days apart, or insertion of intravaginal sponges containing 30 mg (Group III) or 45 mg (Group IV) flurogestone acetate (FGA) for 12 days. The ewes were superovulated with 600 IU PMSG intramuscularly 10 days after the second cloprostenol injection or immediately after sponge removal on Day 12. After the detection of oestrus, the ewes were mated naturally at 6 and 12 h, and some ewes were inseminated laparoscopically. Embryos were recovered surgically 5 or 6 days after service. All ewes exhibited oestrus. The onset of oestrus occurred significantly (P &lt; 0.05) earlier in FGA-treated (50.0 ± 1.5 and 48.0 ± 0.00 h) than in cloprostenol-treated groups. There were no significant differences (P &gt; 0.05) in the mean time of onset of oestrus (50.0 ± 1.5 and 48.0 ± 0.00 h) between the two doses of cloprostenol. The mean number of corpora lutea (8.1 ± 1.26) and embryos recovered (6.1 ± 1.00) was significantly (P &lt; 0.05) higher in ewes treated with 45 mg FGA than in ewes treated with cloprostenol. Embryo recovery rate was significantly (P &lt; 0.05) higher in ewes treated with 45 mg FGA (75.4%) than in other groups (41.7% and 51.6% in 100 μg and 175 μg cloprostenol- and 52.7% in 30 mg FGA-treated groups, respectively). Fertilisation rate was 93.3% in ewes given 100 µg cloprostenol, whereas other groups showed 100% fertilisation rate. The highest percentage (100%) of Grade 1 embryos was in FGA groups. In conclusion, despite FGA protocol presenting superior results, cloprostenol protocol was equally efficient in synchronising oestrus. The embryo recovery rate was better after 45 mg FGA than 30 mg FGA or after either dose of cloprostenol.

Changes accompanying spontaneous embryonic loss in nine mares during the first month of pregnancy

s / Journal of Equine Veterinary Science 34 (2014) 196 196 degenerate conceptuses recovered (Fig 1d,f-h) were very similar, each with a shrunken avascular yolk sac and a complete capsule. Fig. 1. Maternal plasma progesterone concentrations (closed symbols, lefthand scale of each panel, ng/ml) and mean conceptus diameters (open symbols, right-hand scales, mm) at various days after ovulation (bottom scales) in 11 cases of spontaneous embryonic loss or degeneration in singletons before fixation (a-c), singletons after fixation (d-h), and twins(i-k). Proteomic analyses of four uterine flush fluids (two from mares with singletons, Fig 1d,f; two from twin pregnancies, (Fig 1i,j) revealed several major proteins known to be expressed by the endometrium [2] in amounts that were correlated with mean P4 concentrations (Fig 2). Several major endometrial proteins were increased more than 2fold over amounts detected in uterine flushes from normal day-20 pregnancies (Fig 3). Some of these increases corresponded to increases observed 2 days after a luteolytic dose of cloprostenol. Fig. 2. Plasma progesterone relationship with several major endometrial proteins detected by LC-MS/MS in flush fluids from four mares after spontaneous loss of conceptuses. Fig. 3. Mean amounts of some proteins that were increased in flush fluids from four mares with spontaneously failing pregnancies, in comparison with flush fluids from day-20 normal pregnancies (N 1⁄4 5) and day-20 pregnancies from mares given cloprostenol on day 18 (N 1⁄4 5).