Consequences of eight consecutive applications of equine chorionic gonadotropin on ovarian follicle development and ovulation in  bos indicus cows

ABSTRACT: The equine chorionic gonadotropin (eCG) is a glycoprotein produced in mare endometrial calices. In bovine, it is used in estrus synchronization protocols. However, studies have shown that it is potentially immunogenic and its effect can decrease after repetitive use. This study aimed to evaluate antral follicle dynamics, corpus luteum (CL) and ovulation rate in bos indicus cows submitted to an estrus synchronization protocol in association with eCG for eight times consecutively. Ten cyclical, multiparous, and pasture raised beef cows were divided into two groups: control group (n=5) and eCG group (n=5). In 30 day interval, all animals were synchronized with the same estrogen/progesterone based protocol, totalizing 8 re-synchronizations. Cows in the treatment group received 300IU eCG 48 hours prior to the presumable ovulation. Ultrassound examinations were performed on Day 4 of the protocol (approximately 1.5 days after follicle recruitment) to count antral follicles, on Day 10, to count antral follicles and to measure size of the largest follicle and on Day 18 to measure the diameter of the CL. No difference (P>0.05) between follicular growth and size of the pre-ovulatory follicle was reported between groups. Cows treated with eCG had a larger (P<0.05) CL and increased (P<0.05) ovulation rate (18mm and 92%, respectively) when compared with control group (14.1mm and 80%, respectively). Furthermore, consecutive treatments did not affect CL nor ovulation rates. In conclusion, eCG treatment increased CL size and ovulation rate even after 8 consecutive treatments.

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9 TIMED ARTIFICIAL INSEMINATION IN BLOCKS: A NEW ALTERNATIVE TO IMPROVE FERTILITY IN BEEF COWS

Reproduction Fertility and Development ◽

10.1071/rdv27n1ab9 ◽

2015 ◽

Vol 27 (1) ◽

pp. 97

Author(s):

L. F. M. Pfeifer ◽

N. A. Castro ◽

L. G. B. Siqueira ◽

K. R. Lagos ◽

A. Bagon ◽

...

Keyword(s):

Artificial Insemination ◽

Meta Analysis ◽

Bos Indicus ◽

Prostaglandin F2α ◽

Beef Cows ◽

Ovulation Rate ◽

Control Group ◽

Block Group ◽

Preovulatory Follicle ◽

Timed Artificial Insemination

The objective of this study was to evaluate whether timed artificial insemination (TAI) according to the diameter of the dominant preovulatory follicle (POF) would improve pregnancy rates in beef cows. In Experiment 1, a retrospective meta-analysis of 5 oestradiol- or gonadotropin-releasing hormone-based TAI experiments from 2011 to 2014 was performed to evaluate the interval from luteolysis to ovulation. In these experiments, crossbred cows (Gyr × Holstein; n = 60) were examined by ultrasonography at 12-h intervals from progesterone-releasing device (CIDR) removal to ovulation. A linear regression model was used to predict the effect of POF diameter on the time of ovulation. Cows with a larger POF at the time of AI ovulated earlier than cows with smaller POF (y = –8.25x + 115.22; R2 = 0.93; P < 0.0001). In Experiment 2, lactating Nelore cows (Bos indicus; n = 59) on random days of the oestrous cycle were given 2 mg of oestradiol benzoate IM and a CIDR device (Day 0) to synchronize follicular waves. The CIDR were removed, and cows were given 500 μg of d-Cloprostenol (prostaglandin F2α) IM, 1 mg of oestradiol cypionate IM, and 300 IU of eCG IM on Day 8. On the morning of Day 10 (07:00 a.m.), the diameter of the POF was assessed by ultrasonography, and cows were randomised into Control (n = 29) and Block (n = 30) groups. 1) Control-group cows were TAI 48 h after CIDR removal (08:00 a.m. on Day 10), and Block-group cows were inseminated at 4 time points according to the diameter of the POF: B0 (POF ≥15 mm, TAI at 08:00 a.m. on Day 10, n = 6), B1 (POF 13 to 14 mm, TAI at 02:00 p.m. on Day 10, n = 8), B2 (POF 11 to 12 mm, TAI at 08:00 a.m. on Day 11, n = 11), and B3 (POF ≤ 10 mm, TAI at 02:00 p.m. on Day 11, n = 5). Pregnancy status was assessed 30 days post-AI by ultrasonography. No differences were detected in the diameter of the POF 48 h after CIDR removal (P = 0.77) or ovulation rate (P = 0.65; combined ovulation rate 52/59, 88%) between Control and Block groups. Block group had a higher pregnancy rate than Control (22/30, 73% v. 13/29, 45%, respectively; P = 0.02). In conclusion, our results document that interval from luteolysis to ovulation depends on the size of preovulatory follicle, timing of AI in relation to ovulation time is critical, and AI time according to the diameter of the POF can be an effective tool to improve fertility of cows in TAI protocols.

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EFFECT OF KISPEPTIN-10 AS AN ALTERNATIVE TO ECG IN ESTRUS SYNCHRONIZATION PROTOCOL ON IMPROVING THE REPRODUCTIVE PERFORMANCE OF KARADI EWES

IRAQI JOURNAL OF AGRICULTURAL SCIENCES ◽

10.36103/ijas.v52i3.1340 ◽

2021 ◽

Vol 52 (3) ◽

pp. 535-546

Author(s):

T. A. Abdulkareem ◽

S. J. Muhammad ◽

A. N. Yousif

Keyword(s):

Body Weight ◽

Chorionic Gonadotropin ◽

Reproductive Performance ◽

The Other ◽

Control Group ◽

Estrus Synchronization ◽

Serum Progesterone ◽

Live Body Weight ◽

Equine Chorionic Gonadotropin ◽

Synchronization Protocol

This study was conducted to examine the effect of Kisspeptin-10 as an alternative to equine chorionic gonadotropin (eCG) in estrus- synchronization protocol for improving the reproductive performance of Karadi ewes. Forty adult ewes of 3-7 years old and 65–70 kg live body weight were equally divided into four equal groups. Animals were inserted with a progestagen (60 mg MAP)-impregnated sponges for 13 days as estrus synchronization protocol. Following withdrawal of sponges, first group was served as control (C) and intramuscularly injected with normal saline only. The second group was intramuscularly injected with 250 IU of eCG (eCG), while those of third and fourth groups were intravenously injected with 4 and 8 µg /kg body weight of Kisspeptin-10, referred as Kisspeptin1 and Kisspeptin2 groups respectively. Serum progesterone and LH concentrations did not significantly differ among groups before estrus synchronization protocol and eCG or Kisspeptin treatments. The two Kisspeptin-injected groups attained better (P≤0.01) overall mean estrus (100%), fertility (90%), conception (90 and 100%, respectively), lambing (90%), and twinning (10%) rates with lesser barrenness (10%) as compared with the other groups. Moreover, eCG and Kisspeptin groups exhibited greater (P≤ 0.01) percentage of increasing fecundity (233%) and extra lambs born (0.7) than the control group. In conclusion, treatment of Karadi ewes either with Kisspeptin-10 or eCG hormones enhanced the overall reproductive performance, but did not affect serum progesterone and LH concentrations.

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Reproductive performance of Bos indicus beef cows treated with different doses of equine chorionic gonadotropin at the end of a progesterone-estrogen based protocol for fixed-time artificial insemination

Theriogenology ◽

10.1016/j.theriogenology.2018.06.003 ◽

2018 ◽

Vol 118 ◽

pp. 150-156 ◽

Cited By ~ 3

Author(s):

Rafael Herrera Alvarez ◽

Guilherme Pugliesi ◽

Fabio Luis Nogueira Natal ◽

Cecilia Constantino Rocha ◽

Gilmar Arantes Ataide Júnior ◽

...

Keyword(s):

Chorionic Gonadotropin ◽

Reproductive Performance ◽

Artificial Insemination ◽

Bos Indicus ◽

Fixed Time ◽

Beef Cows ◽

Equine Chorionic Gonadotropin ◽

Different Doses

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Should fertile women quit drinking alcohol to produce better quality oocytes?

Zygote ◽

10.1017/s0967199420000696 ◽

2020 ◽

pp. 1-3

Author(s):

Burcu Ozbakir ◽

Pinar Tulay

Keyword(s):

Alcohol Consumption ◽

Young Women ◽

Antral Follicle ◽

Antral Follicle Count ◽

Control Group ◽

Social Drinkers ◽

Antral Follicles ◽

Healthy Women ◽

Significant Difference

Summary Alcohol consumption has long been shown to affect both fetal health and pregnancy. In this study, antral follicle count, maturation level of oocytes including morphological assessment and number of metaphase I (MI), metaphase II (MII) and germinal vesicle (GV) stage oocytes obtained from young women (age < 30 years old) with or without alcohol consumption were investigated. In total, 20 healthy women who were social drinkers and 36 healthy women who do not consume alcohol were involved in this study. Women in both study and control groups were undergoing controlled ovarian stimulation. The antral follicle count and the number and quality of the oocytes retrieved were evaluated and recorded. In total, 635 antral follicles, 1098 follicles and 1014 oocytes with 820 MII, 72 MI and 78 GV stage oocytes were collected from the social drinkers. In the control group, 628 antral follicles, 1136 follicles and 1085 oocytes with 838 MII, 93 MI and 102 GV stage oocytes were evaluated. The results of this study showed that the antral follicle count was very similar in both groups. The number of oocytes and MII stage oocytes was slightly higher in the control group, although it was not a significant difference. This study showed that although the consumption of alcohol may have adverse effects post-implantation, it may not have a solid effect during oogenesis in young women. The results of this study are especially important in clinical settings as some women who are social drinkers undergo in vitro fertilization treatments.

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Efficiency of mating, artificial insemination or resynchronisation at different times after first timed artificial insemination in postpartum Nellore cows to produce crossbred calves

Animal Production Science ◽

10.1071/an17466 ◽

2019 ◽

Vol 59 (2) ◽

pp. 225 ◽

Cited By ~ 1

Author(s):

Walvonvitis Baes Rodrigues ◽

Jean do Prado Jara ◽

Juliana Correa Borges ◽

Luiz Orcirio Fialho de Oliveira ◽

Urbano Pinto Gomes de Abreu ◽

...

Keyword(s):

Pregnancy Rate ◽

Breeding Season ◽

Chorionic Gonadotropin ◽

Artificial Insemination ◽

Fixed Time ◽

Beef Cows ◽

Device Removal ◽

Oestradiol Benzoate ◽

Timed Artificial Insemination ◽

Equine Chorionic Gonadotropin

The objective of this trial was to evaluate different post-timed artificial insemination (TAI) reproductive managements in postpartum beef cows to produce crossbred calves from artificial insemination (AI). Nellore cows (n = 607), with 45 days postpartum, were inseminated at a fixed time, using a protocol that included an intravaginal progesterone-releasing device along with oestradiol benzoate, prostaglandin, equine chorionic gonadotropin, and oestradiol cypionate, followed TAI 48 h post-device removal. Four post-TAI treatments were evaluated: in CONTROL (T1, n = 161), cows were exposed to Nellore clean-up bulls until the end of the breeding season (75 days). In OBSERVATION (T2, n = 132), heat detection was performed for 15–25 days post-TAI, followed by AI. In RESYNC22 (T3, n = 157) and RESYNC30 (T4, n = 157), resynchronisation started after 22 or 30 days, following second TAI at Day 32 or 40 days after first TAI. In T2, T3 and T4, after the second AI, cows were exposed to Nellore clean-up bulls until the end of the breeding season (75 days). The pregnancy rate (PR) for the first TAI did not differ (54.6%, 53.0%, 59.2%, and 51.6% for CONTROL, OBSERVATION, RESYNC 22, and RESYNC 30, respectively; P = 0.66), and no difference was observed for the second TAI (RESYNC 22 = 45.31% and RESYNC30 = 46.05%; P = 0.137), in the PR at the end of the breeding season (86.33%, 86.36%, 78.98%, and 81.52%, P = 0.43), or embryonic losses (4.54%, 2.85%, 6.45% and 7.40%, respectively; P = 0.61), but the percentage of crossbred pregnancy was higher in groups with resynchronisation (RESYNC22 and RESYNC30) than CONTROL and OBSERVATION (98.38%, 90.62%, 63.30%, 78.95%, P < 0.001). In conclusion, resynchronisation programs of 22 or 30 days are more efficient to produce AI products, and the final pregnancy rate is similar among the treatments, differing only in the amount of calves produced by AI.

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FIELD EVALUATION OF ESTRUS SYNCHRONIZATION AND PREGNANCY DETECTION USING ULTRASONOGRAPHY TO THE LOCAL AWASSI EWES FOR SHEEP OWNERS IN KANAAN DISTRICT- DIYALA PROVINCE

IRAQI JOURNAL OF AGRICULTURAL SCIENCES ◽

10.36103/ijas.v47i4.547 ◽

2016 ◽

Vol 47 (4) ◽

Author(s):

Al-Jubouri & Hobi

Keyword(s):

Reproductive Performance ◽

Field Evaluation ◽

High Accuracy ◽

Control Group ◽

Estrus Synchronization ◽

Transabdominal Ultrasonography ◽

Training Courses ◽

Equine Chorionic Gonadotropin ◽

On Farm ◽

Unconventional Methods

The objective of this study was to carry out an on-farm experiment in sheep owner farms in Kanaan district for the period from 7th Feb. 2015 to 27th Mar. 2015 and to identify the unconventional methods in controlling the reproduction in sheep and increase their productivity using 45 local Awassi ewes, randomly selected from three sheep owners (15 ewes / owner). Treatment group (10 ewes/ owner) were treated with a vaginal sponges containing 20 mg fluorogestone acetate (FGA) inserted for 10 days, followed by I.M. injection of 500 IU equine chorionic gonadotropin (eCG), while 5 ewes / owner were regarded as control group without any treatment. Estrus was observed for all ewes for 5 days post withdrawal of sponges. Ewes that showed estrus were mated by rams in their flocks, thereafter, pregnancy detection was conducted at days 35-37 post- mating using transabdominal ultrasonography. A questionnaire involved 20 sheep owners and a demonstrative field day was conducted for owners contributed in the experiment, and others from the region of study to explain the importance and results of the experiment. The results showed the appearance of estrus in all ewes 100% within three days after the withdrawal of sponges. Pregnancy rate of 85.71% at days 35-37 of mating. The questionnaire showed there is an urgent need of knowledge for owners to find out the importance of controlling the reproductive cycle in sheep using vaginal sponges. Also, there were a correlation between the need of knowledge for sheep owners with (educational level for most of them, herd sizes, income from breeding, training courses and other activities in the fields of breeding and reproduction of sheep). In conclusion, the technology of estrus synchronization has an important role to improve reproductive performance of sheep and pregnancy could be detected through transabdominal ultrasonography at 35-37 days with high accuracy as well as there is great desire for the most owner to conduct estrus synchronization technique and to take care their birth of herds simultaneously.

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173 A COMBINED RECOMBINANT BOVINE SOMATOTROPIN/EQUINE CHORIONIC GONADOTROPIN PROTOCOL IN THE ZEBU BREED TABAPUA AND HOLSTEIN HEIFERS SUBMITTED TO OVUM PICKUP

Reproduction Fertility and Development ◽

10.1071/rdv23n1ab173 ◽

2011 ◽

Vol 23 (1) ◽

pp. 188

Author(s):

J. C. de Souza ◽

H. de Morais ◽

R. Spuri ◽

R. C. Andrade ◽

T. L. C. Pinto

Keyword(s):

Chorionic Gonadotropin ◽

Transvaginal Ultrasound ◽

Ovarian Follicle ◽

Interactive Effect ◽

Bovine Somatotropin ◽

Recombinant Bovine Somatotropin ◽

Oocyte Yield ◽

Equine Chorionic Gonadotropin ◽

And Control ◽

Zebu Breed

The aim of this study was to enhance ovarian follicular development and subsequent oocyte retrieval by the use of a combined equine chorionic gonadotropin (eCG) and recombinant bovine somatotropin (rbST) protocol, as well as to compare its efficiency between the Brazilian zebu breed Tabapua (TAB) and Holstein (HOL) nulliparous heifers. In a changeover design, TAB (n = 16) and HOL (n = 12) were allocated to 1 of 2 protocols in 2 distinct periods. Two days before initiation of the protocols (D2), dominant follicles were ablated by transvaginal ultrasound-guided aspiration: Group 1: on day 0 (D0) a subcutaneous injection of 500 mg of rbST (Boostin®, Intervet, SP) and on D2 an intramuscular injection of 500 IU of eCG (Novormon®, Schering-Plough-Intervet, SP); and control: vehicle only. Two days later (D4), ovum pickup (OPU) was performed and the ovarian follicle population was evaluated by ultrasound. Twenty days after the first OPU session, heifers were switched over across treatments and were aspirated a second time, so that a total of 28 sessions were performed for each treatment. Main effects of period, breed, and protocol and their interactions on follicle numbers and oocyte yield were analysed through the GENMOD procedure of SAS (SAS®, Cary, NC, USA) using the Poisson distribution option. Means were compared by orthogonal contrasts, and the probability value set at 0.05 for significance unless otherwise specified. There was an interaction effect between hormonal stimulation and breed (P < 0.05) on the number of aspirated follicles (2 to 10 mm in diameter) such that they were higher in TAB treated (41.4 ± 2.6) compared with control (29.9 ± 2.6) heifers and did not differ between the HOL heifers (15.5 ± 2.6 v. 14.4 ± 2.6 in treated and control heifers, respectively). Overall, follicle numbers were higher (P < 0.0001) in TAB (35.6 ± 1.84) than in HOL (15.0 ± 2.1) heifers and in treated (28.4 ± 2.0) v. control (22.1 ± 2.0) heifers (P < 0.001). There was no effect (P = 0.77) of treatment on total viable oocytes (grades 1 to 3) between treated (3.5 ± 1.2) and control (3.9 ± 1.1) heifers. Tabapuã heifers had more (P < 0.05) viable oocytes than HOL (5.9 ± 0.9 v. 1.6 ± 1.4). In conclusion, the proposed protocol may improve OPU results but viable oocyte yield was not associated to the higher number of follicles available for aspiration. It may be necessary to modify this protocol to improve results perhaps by increasing the time window between rbST and eCG injections as well as by increasing the rbST dosage for heifers. The present protocol may be cost saving, compared with follicle stimulating hormone, for initial OPU sessions in the case of Tabapuã heifers because it is expected that responses decrease after a sequence of eCG injections. It is also interesting to notice that it is possible that HOL heifers already have higher endogenous growth hormone concentrations, which could help to explain the interactive effect observed in the ovarian response. Further studies are necessary to improve this protocol especially in HOL heifers. CNPQ, CAPES, Schering-Plough-Intervet.

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138 Relationships Between Antral Follicle Count, Ovarian Volume, Pre-Antral Follicle Number, and Oocyte Quality

Reproduction Fertility and Development ◽

10.1071/rdv30n1ab138 ◽

2018 ◽

Vol 30 (1) ◽

pp. 209

Author(s):

G. L. Vasconcelos ◽

R. Maculan ◽

N. Alves ◽

A. L. A. P. L. Ribeiro ◽

A. W. B. Silva ◽

...

Keyword(s):

Ovarian Follicle ◽

Primordial Follicle ◽

Antral Follicle ◽

Oocyte Quality ◽

Antral Follicle Count ◽

Primary Follicle ◽

Ovarian Volume ◽

Primordial Follicles ◽

Antral Follicles ◽

Grade 3

The objective was to evaluate the possible relationships between AFC, ovarian volume, ovarian follicle reserve and oocyte quality in abattoir-derived ovaries (experiment 1) and in cows (experiment 2) submitted to OPU. Antral follicle counts of ≥25, 16 to 24, and ≤ 16 were used to define AFC classes as high (HAFC), intermediate (IAFC), and low (LAFC) in both experiments. In experiment 1, after antral follicles were aspirated, abattoir ovaries (n = 10 per AFC class) were processed by conventional histology and pre-antral follicles were counted within primordial, primary, secondary, and tertiary classes and classified as either healthy or degenerate under regular microscopy (Cushman et al. 1999). In experiment 2, HAFC (n = 42), IAFC (n = 34), and LAFC (n = 29) cows were submitted to OPU and oocytes classified as grades 1, 2, and 3 or degenerate (IETS, 2010). Antral follicles (≥3 mm in diameter) were counted by ultrasonography. Data were analysed by GENMOD and GLM procedures of SAS (SAS Institute Inc., Cary, NC, USA) after transformations, when required. In experiment 1, mean normal primordial follicle number was higher (P < 0.001) in HAFC (137.0 ± 1.6)a compared with IAFC (52.6 ± 1.9)b and LAFC (20.2 ± 5.3)c ovaries. However, the mean number of degenerate primordial follicles was lower (P < 0.001) in low count ovaries (2.4 ± 0.6) compared with HAFC (19.0 ± 4.7) and IAFC (16.4 ± 1.5, P < 0.001). Normal primary follicle number was higher in the HAFC compared with IAFC and LAFC ovarian classes (86.2 ± 7.0a v. 34.6 ± 5.1b and 14.4 ± 3.3c, respectively; P < 0.01). Degenerate primary follicles were higher in the HAFC compared with LAFC ovarian class (16.8 ± 6.5 v. 5.2 ± 2.64; P < 0.05). Normal secondary follicle number was also higher in the HAFC compared to LAFC ovarian classes (25.2 ± 7.67 v. 2.4 ± 0.8; P < 0.05). The number of degenerate secondary follicles differed (P < 0.01) only between the IAFC and the LAFC ovarian classes (0.6 ± 0.4 and 7.2 ± 2.4, respectively), which were similar (P > 0.5) to the HAFC class (3.8 ± 1.0). In experiment 2, grade 1, 2, and 3 oocytes, viable oocytes, and ovarian volume (mm3) were higher (P < 0.001) in HAFC compared with IAFC and LAFC cows (grade 1: 7.9 ± 0.6a, 4.9 ± 0.7b and 3.3 ± 0.7c; grade 2: 4.0 ± 0.4a, 2.8 ± 0.4b and 1.2c; grade 3: 2.1 ± 0.4a, 2.5 ± 0.4a and 1.3 ± 0.5b, respectively; viable oocytes: 16.3 ± 1.1a, 13.1 ± 1.2b, and 8.1 ± 1.3c, respectively; (volumes: 12.6 ± 0.7a, 10.1 ± 0.8b, and 8.1 ± 0.9c, respectively). In conclusion, high AFC is linked to a higher follicular reserve, oocyte quality, and ovarian volume. It is safe to apply AFC in the selection of bovine females without compromising oocyte or pre-antral follicular population qualities.

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