12 Effect of additional prostaglandin F2α during the Ovsynch protocol applied in different postpartum intervals in lactating dairy cows: Preliminary results

2019 ◽  
Vol 31 (1) ◽  
pp. 132
Author(s):  
A. Bover ◽  
J. Casellas ◽  
T. Mogas
Keyword(s):  
Dairy Cows ◽  
Pregnancy Rate ◽  
Animal Health ◽  
Prostaglandin F2α ◽  
Gonadotropin Releasing Hormone ◽  
Pregnancy Rates ◽  
Ongoing Research ◽  
Releasing Hormone ◽  
Preliminary Results ◽  
Synchronization Protocol

Timed AI (TAI) programs have been developed to increase the service risk. However, when Ovsynch is used as a synchronization protocol, lack of regression of the corpus luteum after prostaglandin F2α (PGF) administration has been demonstrated, leading to reductions in fertility. In this way, a second PGF administration might increase the frequency of achieving complete luteolysis. This study aimed to evaluate the effect of an additional treatment with PGF on fertility when an Ovsynch synchronization protocol was applied at different postpartum intervals. Multiparous high-production dairy cows (n=471) of a commercial farm were stratified by postpartum intervals [<120 (n=136), 120-150 (n=131), 150-180 (n=92), 180-210 (n=52), and >210 days (n=60)] and randomly allocated to receive either the Ovsynch (n=108) or Ovsynch with second PGF protocol (n=243). Cows inseminated 12h after observed heat detection (AI) served as a control (n=120). The Ovsynch protocol consisted of an injection of gonadotropin-releasing hormone (100 µg; Fertagyl®, Intervet, Millsboro, MD, USA) on Day 0, an injection of PGF (0.5 mg; Estrumate®, Schering-Plough Animal Health, Montréal, QC, Canada) on Day 7, another injection of gonadotropin-releasing hormone (100µg) on Day 9, and timed insemination on Day 10. The Ovsynch with second PGF protocol consisted of the same hormone injection schedule as the Ovsynch protocol, but a second injection of PGF (0.5 mg; Estrumate®) was administered 24h after the first PGF. Data were analysed using the chi-square test. The level of significance was taken as P<0.05. When data were pooled at 120 to 150 days of postpartum interval, pregnancy rate was higher, but not significantly different (P>0.05), for cows that received the Ovsynch (37.5%, n=32) or Ovsynch with second PGF protocol (33.8%, n=77) compared to nonsynchronized cows (22.8%, n=22). After 180 days of postpartum interval, Ovsynch with second PGF protocol triggered pregnancy rates similar to those of nonsynchronized cows (33.3%, n=21 and 28.6%, n=14), whereas the Ovsynch protocol resulted in lower percentages (11.8%, n=17; P>0.05). Similar pregnancy rates (P>0.05) were observed when TAI protocols were administered before 120 days (26.5 and 30.2% for Ovsynch and Ovsynch with second PGF, respectively) or between 150 and 180 postpartum days (31.8 and 33.9% for Ovsynch and Ovsynch with second PGF, respectively) compared with AI cows (25.7 and 28.8% for <120 days and between 150 and 180 postpartum days, respectively). These preliminary results showed a tendency of a better pregnancy rate when both TAI synchronization protocols were applied between 120 and 150 postpartum days when compared with AI. Also, the application of a second dose of PGF seems recommendable when the Ovsynch protocol is used to synchronize cows of >180 postpartum days. Ongoing research will allow an increase in the number of the samples in each postpartum interval in order to confirm these results.

12 EFFECT OF HUMAN CHORIONIC GONADOTROPIN (hCG) ADMINISTRATION ON DAY 2 OR DAY 5 AFTER OESTRUS ON PREGNANCY RATE IN HIGH-YIELDING DAIRY COWS

2015 ◽  
Vol 27 (1) ◽  
pp. 98 ◽  
Author(s):  
J. M. Sanchez ◽  
V. Maillo ◽  
L. Molina ◽  
C. C. Perez-Marin ◽  
P. Lonergan ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Pregnancy Rate ◽  
Body Condition Score ◽  
Significant Proportion ◽  
Prostaglandin F2α ◽  
Gonadotropin Releasing Hormone ◽  
Pregnancy Rates ◽  
Holstein Cows ◽  
Control Group ◽  
Releasing Hormone

In cattle, ~40% of embryonic loss occurs in the period from Day 8 to Day 16 of pregnancy. A significant proportion of embryo loss may be due to inadequate circulating progesterone (P4) concentrations. Low P4 concentrations have also been implicated as a causative factor in the low pregnancy rates (PR) observed in high-yielding dairy cows. Administration of hCG during the early luteal phase stimulates hypertrophy of the original corpus luteum (CL) and, depending on the day of administration, induces ovulation of the first-wave dominant follicle and formation of a functional accessory CL, which increases circulating P4 concentrations. The aim of this study was to examine whether administration of hCG on Day 2 or Day 5 after oestrus after timed AI (TAI) would lead to an increase in pregnancy rates in dairy cattle. Lactating Holstein cows (n = 194) from 12 commercial dairy herds in Southern Spain (37.8833° N, 4.7667° W) with an average milk production at 37.8 L/cow per day and typically with a PR to first AI of ~30% were randomly assigned based on their body condition score (2.65 ± 0.05; mean ± SEM), parity (2.60 ± 0.09), and days in milk (75.06 ± 0.63) to 1 of 3 treatments and administered a single intramuscular injection of 3000 IU of hCG (4 mL of Veterin Corion) either (1) on Day 2 = 36 h after TAI (n = 65; hCG2 group), (2) Day 5 = 108 h after TAI (n = 64; hCG5 group), or (3) 4 mL of saline on Day 2 = 36 h after TAI (n = 65; control group). Cows were synchronized using a 7-day Ovsynch TAI protocol that included a P4-releasing intravaginal device (PRID DELTA 1.55 g). First, gonadotropin-releasing hormone (Cystorelin 100 mg) treatment was administered at PRID insertion (Day 0) followed by 25 mg Dinoprost (prostaglandin F2α: Enzaprost T) on Day 7 at PRID withdrawal. Then, 56 h later, the second gonadotropin-releasing hormone (100 mg) treatment was administered and all cows were inseminated 16 h later. Pregnancy was diagnosed by ultrasonography 28 to 32 days after TAI. Logistic regression model and chi-squared test were used to analyse data. Pregnancy rate to AI was significantly higher in the hCG2 and hCG5 groups than in the control group (43.1 and 45.3%, v. 27.7%; P < 0.05). A treatment-by-parity interaction was observed; while pregnancy rate for primiparous cows was not affected by treatment, multiparous cows from the hCG2 group had greater pregnancies per AI than those in the control group (47.2% v. 21.1%, respectively; P < 0.05). In conclusion, these preliminary results suggest that hCG administration on Day 2 and 5 after oestrus increases PR at first postpartum AI in Holstein cows. In addition, hCG on Day 2 increases the fertility in multiparous cows.This study was funded by the Spanish Ministry of Science and Innovation (AGL2012–37510) and partially supported by Ceva Salud Animal S.A., Spain – synchronization protocol and DFV, Spain – hCG treatments.

Estrous synchronization and fertility of cross-bred dairy cows using prostaglandin F2α and gonadotropin releasing hormone

2021 ◽  
pp. 171-175
Author(s):  
Abubakr O. Ismail ◽  
◽  
Erneo B. Ochi ◽  
Ambrose S. Jubara ◽  
Bakri Ahmed A/Rahim ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Artificial Insemination ◽  
Prostaglandin F2α ◽  
Fixed Time ◽  
Gonadotropin Releasing Hormone ◽  
Pregnancy Rates ◽  
Releasing Hormone ◽  
Treatment Groups ◽  
Estrous Synchronization ◽  
Descriptive Statistical Analysis

A comparative hormonal study of prostaglandin, gonadotropin releasing hormone and their combination was conducted on 30 randomly selected cross-bred dairy cows of SEMEX project for artificial insemination in Hillat Kuku, Khartoum North, Sudan. The study attempts to determine the response of the animals to hormonal induction and synchronization of estrous as well as fertility following fixed time artificial insemination. Three treatment groups of 10 cows each were undertaken. Groups 1, 2 and 3 involved administration of prostaglandin F2α (PGF2α), gonadotropin releasing hormone (GnRH) and a combination of PGF2α + GnRH, respectively. Descriptive statistical analysis was performed. The results revealed that all the three protocols induced and synchronized estrous were almost synchronous in all the treated groups. However, protocol 3 revealed a significantly (p<0.05) better result of 70% pregnancy rate compared to other two protocols that equally provided 50% pregnancy rates. The study resolves that protocol 3 be highly recommended to change the mindset of farmers about the spread of reproductive technology in Sudan. Protocols 1 and 2 provided acceptable pregnancy rates that can be enhanced with the improvement of management.

18 PREGNANCY RATES IN LACTATING DAIRY COWS TREATED WITH GONADOTROPIN-RELEASING HORMONE-BASED SYNCHRONIZATION PROGRAMS AND INSEMINATED AT A FIXED TIME

2013 ◽  
Vol 25 (1) ◽  
pp. 156
Author(s):  
D. Romero ◽  
G. Romero ◽  
G. Veneranda ◽  
L. Filippi ◽  
D. Racca ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Pregnancy Rate ◽  
Milk Production ◽  
Animal Health ◽  
Fixed Time ◽  
Gonadotropin Releasing Hormone ◽  
Pregnancy Rates ◽  
Lactating Dairy Cows ◽  
Pfizer Animal Health ◽  
Group 3

An experiment was designed to compare pregnancy rates in lactating dairy cows synchronized with a 7-day CIDR-Synch or a 5-day CIDR-Synch program and to determine if the addition of a second prostaglandin F2α (PGF) injection to the 7-day CIDR-Synch program would improve pregnancy rates following fixed-time AI (FTAI). The experiments were performed on 2 dairy farms in Argentina, with year-round calving and a mixed feeding system (35% grazing plus 65% corn silage and grain). Cows (n = 621) were 39.3 ± 6.5 days in milk (DIM, mean ± SD) when they were enrolled in the program, had 2.4 ± 1.5 lactations and a body condition score (BCS) of 3.1 ± 0.2 (range: 2.7 to 4.0). All cows received a pre-synchronization treatment with 2 doses of prostaglandin (PGF, 25 mg of dinoprost, Lutalyse, Pfizer Animal Health, Argentina) 14 days apart, and 11 days after the second PGF (Day 0) received 10 µg of Buserelin (GnRH, Receptal, MSD-Intervet, Argentina) and a CIDR device (1.9 g of progesterone, Pfizer Animal Health). Cows were randomly allocated to 1 of 3 groups. The CIDR devices were removed and PGF was administered to cows in Groups 1 and 2 on Day 7. A second GnRH was given 56 h later and cows experienced FTAI 16 h after gonadotropin-releasing hormone (GnRH) injection (i.e. 72 h after CIDR removal). Cows in Group 2 also received a second PGF injection on the afternoon of Day 7. Cows in Group 3 had the CIDR removed and received 2 PGF injections 12 h apart on Day 5. A second dose of GnRH was given and FTAI was performed at the same time, on Day 8 (i.e. 72 h after CIDR removal). All cows were examined by ultrasonography (Aloka 500V, Aloka, Tokyo, Japan) on the day of the first PGF injection and at CIDR removal to determine the presence and number of corpora lutea (CL), and 30 days after FTAI to determine pregnancy status. Data were analyzed by logistic regression to determine the effects of treatment, parity, days postpartum, milk production, BCS, presence of a CL at enrollment, and number of CL at the time of CIDR removal on pregnancy rates. Overall pregnancy rates did not differ among groups: 32.9% (68/207), 38.2% (78/204), and 38.3% (80/209) for Groups 1, 2, and 3, respectively (P = 0.2). Although the number of CL present at CIDR removal did not significantly affect pregnancy rates (P = 0.4), pregnancy rates in cows with 1 CL in Groups 1 and 2 tended to differ [29.0% (11/38) v. 48.9% (21/43); P < 0.07], but neither differed from that in Group 3 [37.2% (16/43)]. No differences were detected among groups in cows without a CL at CIDR removal [overall pregnancy rate: 29.4% (5/17)] and those with ≥2 CL [overall pregnancy rate: 36.1% (173/479)]. Among the other variables evaluated, first-parity cows had 1.96 (1.38–2.78) times more chance of getting pregnant than second-or-more-parity cows (P = 0.002) and cows with BCS >3 had 1.63 (1.16–2.28) times more chance of getting pregnant than those with BCS <3 (P = 0.003). Finally, herd, days postpartum, milk production, and presence of a CL at enrollment did not significantly affect pregnancy rates. We concluded that the 3 treatments resulted in similar pregnancy rates for lactating dairy cows and that the benefit of adding a second PGF injection to the 7-day protocol was only marginal in cows with 1 CL at CIDR removal.

8 EFFECT OF SUPPLEMENTATION WITH ESTRADIOL OR ESTRADIOL PLUS GONADOTROPIN-RELEASING HORMONE AFTER PROSTAGLANDIN F2α ADMINISTRATION ON THE PREGNANCY RATES FOLLOWING TIMED ARTIFICIAL INSEMINATION IN DAIRY COWS

2012 ◽  
Vol 24 (1) ◽  
pp. 115
Author(s):  
J. K. Jeong ◽  
H. G. Kang ◽  
I. H. Kim
Keyword(s):  
Dairy Cows ◽  
Pregnancy Rate ◽  
Artificial Insemination ◽  
Animal Health ◽  
Prostaglandin F2α ◽  
Pregnancy Rates ◽  
Gnrh Analogue ◽  
Chi Square ◽  
Array Transducer ◽  
Timed Artificial Insemination

This study determined the effect of supplementation with oestradiol or oestradiol plus GnRH after PGF2α administration on pregnancy rates after timed artificial insemination (TAI) in dairy cows. Three hundred and six Holstein dairy cows with corpus luteum confirmed by ultrasonography (Tringa Linear with 5.0 MHz array transducer; Esaote Pie Medical, Maastricht, the Netherlands) were randomly allocated to three treatments: a single injection of 500 μg of cloprostenol, PGF2α analogue (Estrumate, Schering-Plough Animal Health, Friesoythe, Germany; PGF2α group, n = 115) designated as 0 h, an injection of 500 μg of cloprostenol and an injection of 1 mg of oestradiol benzoate (EB, SY Esrone; Samyang, Seoul, Korea) 56 h later (PGF2α + EB group, n = 114), or the same treatment as in the PGF2α + EB group and an additional injection of 100 μg of gonadorelin, GnRH analogue (Godorel, Uni-Biotech Co., Ltd., Korea) 24 h later (PGF2α + EB + GnRH group, n = 77). All cows in each group received TAI 80 h after the PGF2α injection. Pregnancy was determined at 40 to 50 days after TAI by using both ultrasonography and rectal palpation. Pregnancy rate among groups were compared by the chi-square test using the SAS program (version 9.1: SAS Institute Inc., Cary, NC, USA). Pregnancy rate following TAI were higher (P < 0.05) in the PGF2α + EB + GnRH group (34/77, 44.2%) than in the PGF2α group (31/115, 27.0%), with the PGF2α + EB group intermediate (39/114, 34.2%). In conclusion, the supplementation with oestradiol plus GnRH after PGF2α administration improved pregnancy rate after TAI in dairy cows. This work was supported by the research grant of the Chungbuk National University in 2011.

Effect of gonadotropin-releasing hormone and prostaglandin F2α on reproduction in postpartum dairy cows

1983 ◽  
Vol 19 (6) ◽  
pp. 763-770 ◽  
Author(s):  
G.F. Richardson ◽  
L.F. Archbald ◽  
D.M. Galton ◽  
R.A. Godke
Keyword(s):  
Dairy Cows ◽  
Prostaglandin F2α ◽  
Gonadotropin Releasing Hormone ◽  
Releasing Hormone

9 EFFECT OF TIMING OF INSEMINATION WITH SORTED SEMEN ON SUBSEQUENT PREGNANCY RATE IN POSTPARTUM BEEF COWS SYNCHRONIZED WITH A MODIFIED 14-DAY PROGESTERONE PROTOCOL

2014 ◽  
Vol 26 (1) ◽  
pp. 119
Author(s):  
A. J. Davis ◽  
J. G. Powell ◽  
T. D. Lester ◽  
R. W. Rorie
Keyword(s):  
Pregnancy Rate ◽  
Animal Health ◽  
Prostaglandin F2α ◽  
Beef Cows ◽  
Subsequent Pregnancy ◽  
Pregnancy Rates ◽  
Treatment Groups ◽  
Rate Analysis ◽  
Chi Squared ◽  
Pregnancy Status

A study investigated the effect of AI timing on pregnancy rate when using X sorted semen, and whether prostaglandin F2α (PGF2) injection on Day 7 of a modified 14-day progesterone (P4) protocol improved oestrous response in beef cows. Angus-based cows were allotted across treatment groups by cyclicity, parity, weight, body condition, and days postpartum. Treatment 1 (n = 132) cows received a CIDR P4 insert (Eazi-Breed CIDR, Pfizer Animal Health, Groton, CT, USA) on Day 0, with CIDR removal on Day 14, followed by 100 μg of gonadotropin-releasing hormone (GnRH; Factrel, Pfizer) on Day 16, and 25 mg of PGF2 (Lutalyse, Pfizer) on Day 23. Treatment 2 (n = 132) cows received the same synchronization treatment, except for an additional 25 mg dose of PGF2 given on Day 7 of CIDR treatment. Cows were observed for oestrus over an 84-h period and inseminated with X-sorted semen at 9 to 14, 15 to 17, 18 to 21 or 22 to 24 h after detected oestrus, followed 10 days later by exposure to fertile bulls for 45 days. Ultrasonography was used to determine pregnancy status ~45 days after AI and again 45 to 55 days after bull removal. Chi-squared analysis was used to determine the effects of treatment on oestrus response, AI pregnancy, and seasonal pregnancy rates, and the effect of AI timing on pregnancy rate. Analysis of variance was used to determine the effects of treatment on the interval from PGF2 dosing to detected oestrus. Oestrus response to synchronization treatment was similar (P = 0.33) at 76.5 and 71.2% for cows in Treatments 1 and 2, respectively. The mean interval from PGF2 to the onset of oestrus was extended (P = 0.03) ~3 h for cows in Treatment 2 (57.4 v. 54.3 h, respectively). About two-thirds of the cows in each treatment were cyclic at the start of synchronization. The extended interval from PGF2 to observed oestrus was due to an effect on cyclic, but not acyclic, cows in Treatment 2. Of the cows expressing oestrus, 69 and 89% expressed oestrus 48 to 72 h post-PGF2 in Treatments 1 and 2, respectively. Pregnancy rates after AI with sorted semen were similar (P = 0.64) at 63.3 and 66.7% for Treatments 1 and 2, respectively. No differences (P = 0.98) were detected in AI pregnancy rates for insemination intervals ranging from 9 to 24 h after detected oestrus. At the end of the breeding season, seasonal pregnancy rates were also similar (P = 0.74), at 83.3 and 84.9% for cows in Treatments 1 and 2, respectively. The addition of a PGF2 treatment on Day 7 of our 14-day CIDR-based protocol was expected to ensure all cows has sub-luteal P4 concentrations and would develop a persistent follicle capable of ovulation in response to GnRH given on Day 16. Whereas the Day 7 PGF2 treatment had no effect on oestrus response or pregnancy rate, it did result in a more synchronous oestrus within a 24-h period. Results indicate that acceptable pregnancy rates can be achieved in lactating beef cows when using sorted semen over a range of insemination times.

7 COMPARISON OF TIMED ARTIFICIAL INSEMINATION PROTOCOLS USING PROSTAGLANDIN F2α+ESTRADIOL OR PROSTAGLANDIN F2α+ESTRADIOL+GONADOTROPIN-RELEASING HORMONE IN DAIRY COWS

2012 ◽  
Vol 24 (1) ◽  
pp. 115
Author(s):  
J. K. Jeong ◽  
H. G. Kang ◽  
I. H. Kim
Keyword(s):  
Dairy Cows ◽  
Pregnancy Rate ◽  
Artificial Insemination ◽  
Prostaglandin F2α ◽  
Pregnancy Rates ◽  
Gnrh Analogue ◽  
Chi Square ◽  
Array Transducer ◽  
Chi Square Test ◽  
Timed Artificial Insemination

This study compared pregnancy rates following 2 timed artificial insemination (TAI) protocols using PGF2α + oestradiol or PGF2α + oestradiol + GnRH in dairy cows. Four hundred fifty-five Holstein dairy cows, 2.2 ± 0.1 in parity, 148.3 ± 3.6 days in milk, with corpus luteum of greater than 20 mm diameter confirmed by ultrasonography (Tringa Linear with 5.0 MHz array transducer; Esaote Pie Medical, Maastricht, the Netherlands) were randomly divided into two treatments: an injection of 500 μg of cloprostenol, PGF2α analogue (Iliren cycle BP®, Intervet International GmbH, Unterschleissheim, Germany) and an injection of 2 mg of oestradiol benzoate (EB, SY Esrone, Samyang, Seoul, Korea) 36 h later (PGF2α + EB group, n = 257), or an injection of 500 μg of cloprostenol, an injection of 2 mg of EB 36 h later and an additional injection of 100 μg of gonadorelin, GnRH analogue (Godorel, Uni-Biotech Co., Ltd., Korea) 24 h later (PGF2α + EB + GnRH group, n = 198). All cows in the two groups received TAI 24 h after the EB injection. Pregnancy was determined at 40 to 50 days after TAI by using both ultrasonography and rectal palpation. Pregnancy rates between the PGF2α + EB and PGF2α + EB + GnRH groups were compared by the chi-square test using the SAS program (version 9.1: SAS Institute Inc., Cary, NC, USA). Pregnancy rate following TAI did not differ between the PGF2α + EB (32.7%) and PGF2α + EB + GnRH groups (34.9%; P > 0.05). In conclusion, addition of GnRH for TAI protocol using PGF2α + oestradiol did not improve pregnancy rate in dairy cows.

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