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Azari-Dolatabad N, Benedetti C, Velez DA, Montoro AF, Sadeghi H, Residiwati G, Leroy JLMR, Van Soom A, Pascottini OB. Oocyte developmental capacity is influenced by intrinsic ovarian factors in a bovine model for individual embryo production. Anim Reprod Sci 2023; 249:107185. [PMID: 36610102 DOI: 10.1016/j.anireprosci.2022.107185] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 11/21/2022] [Accepted: 12/28/2022] [Indexed: 12/31/2022]
Abstract
The ovary and its hormones may have major effects on the in vitro developmental capacity of the oocytes it contains. We related intrinsic ovarian factors namely the presence of corpus luteum (CL) and/or dominant follicle (>8 mm) and the follicular count to cumulus expansion (CE), embryo development, and blastocyst quality in a bovine model. Cumulus-oocyte-complexes (COCs) were aspirated from follicles between 4 and 8 mm in diameter. In vitro embryo production was performed in a fully individual production system. The follicular fluid from which COCs were collected was pooled (per ovary) to evaluate the estrogen, progesterone, and insulin-like growth factor-1 (IGF-1) concentrations. Cumulus oocyte complexes collected from ovaries without a CL presented a greater CE than COCs derived from ovaries bearing CL. The absence of ovarian structures increased the blastocyst rate when compared to oocytes derived from ovaries with a CL, a dominant follicle, or both. Blastocysts derived from ovaries without a dominant follicle presented higher total cell numbers and a lower proportion of apoptosis than blastocysts derived from ovaries containing a dominant follicle. Cumulus oocyte complexes collected from ovaries with high follicular count resulted in higher cleavage than from ovaries with low follicular count, but the blastocyst rate was similar between groups. Ovaries bearing a CL had greater progesterone and IGF-1 follicular fluid concentrations in neighboring follicles than ovaries without a CL. Selection for bovine ovaries without CL or dominant follicle can have positive effects on CE, embryo development, and blastocyst quality in an individual embryo production system set-up.
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Affiliation(s)
- Nima Azari-Dolatabad
- Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium; Department of Veterinary Sciences, Gamete Research Center, Veterinary Physiology and Biochemistry, University of Antwerp, Wilrijk, Belgium.
| | - Camilla Benedetti
- Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Daniel Angel Velez
- Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium; Research Group in Animal Sciences - INCA-CES, School of Veterinary Medicine and Animal Production, Universidad CES, Medellin, Colombia
| | - Andrea Fernandez Montoro
- Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Hafez Sadeghi
- Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Gretania Residiwati
- Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Jo L M R Leroy
- Department of Veterinary Sciences, Gamete Research Center, Veterinary Physiology and Biochemistry, University of Antwerp, Wilrijk, Belgium
| | - Ann Van Soom
- Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Osvaldo Bogado Pascottini
- Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium; Department of Veterinary Sciences, Gamete Research Center, Veterinary Physiology and Biochemistry, University of Antwerp, Wilrijk, Belgium
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2
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Synchronization of stage of follicle development before OPU improves embryo production in cows with large antral follicle counts. Anim Reprod Sci 2020; 221:106601. [PMID: 32961391 DOI: 10.1016/j.anireprosci.2020.106601] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 09/09/2020] [Accepted: 09/10/2020] [Indexed: 11/21/2022]
Abstract
In the present study, there was an evaluation of in vitro embryo production (IVEP) in Bos indicus donor cows with small or large antral follicle counts (AFCs) when there was synchronization of follicular dynamics among cows before ovum pick-up (OPU). Donor cows classified as having small or large AFC were submitted to OPU/IVEP program (Experiment-I) or had follicular-stage synchronization imposed before OPU/IVEP (Experiment-II). In Experiment-I, the cows with a large AFC had a greater (P < 0.01) mean of embryos developing to the blastocyst stage compared to those with a small AFC. In Experiment-II, percentage of viable oocytes/OPU were not affected (P = 0.33) by synchronization of follicular dynamics, but the AFC had an effect (P < 0.0001). There was an interaction (P = 0.01) indicating the larger AFC, with or without imposing of a synchronization treatment regimen, resulted in the most desirable outcome. The number of embryos was affected (P < 0.001) by follicular-stage synchronization and AFC, with there being an interaction (P = 0.002) with the most desirable results for the large AFC-synchronized group. Number of pregnancies was greater (P ≤ 0.02) for recipient females with embryos from synchronized donors and with a large AFC. There was an interaction (P = 0.03) with there being a greater pregnancy percentage for cows with synchronized follicular stages and the large AFC. Bos indicus donor with a large AFC when associated with the synchronization of stage of follicular dynamics pre-OPU results in improvement of the efficacy of IVEP.
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Superovulatory response following FSH, eCG-FSH and hMG and pregnancy rates following transfer of hatched blastocyst embryos with different diameter and shape in dromedary camel. Theriogenology 2018; 106:149-156. [DOI: 10.1016/j.theriogenology.2017.10.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2017] [Revised: 10/05/2017] [Accepted: 10/09/2017] [Indexed: 11/24/2022]
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4
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Kim E, Jhun H, Kim J, Park U, Jo S, Kwak A, Kim S, Nguyen TT, Kang Y, Choi I, Lee J, Kim H, Kim Y, Lee S, Kim S. Species Specific Antiviral Activity of Porcine Interferon-α8 (IFNα8). Immune Netw 2017; 17:424-436. [PMID: 29302255 PMCID: PMC5746612 DOI: 10.4110/in.2017.17.6.424] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Revised: 12/01/2017] [Accepted: 12/04/2017] [Indexed: 01/23/2023] Open
Abstract
Interferons (IFNs) have been known as antiviral genes and they are classified by type 1, type 2, and type 3 IFN. The type 1 IFN consists of IFNα, IFNβ, IFNτ, and IFNω whereas the type 2 IFN consists of only IFNγ, which is a key cytokine driving T helper cell type 1 immunity. IFNλ belongs to the type 3 IFN, which is also known as IL-28 and IL-29 possessing antiviral activities. Type 1 IFN is produced by viral infection whereas type 2 IFN is induced by mitogenic or antigenic T-cell stimuli. The IFNτ of bovine was first discovered in an ungulate ruminant recognition hormone. IFNτ belongs to the type 1 IFN with the common feature of type 1 IFN such as antiviral activity. IFNs have been mostly studied for basic research and clinical usages therefore there was no effort to investigate IFNs in industrial animals. Here we cloned porcine IFNα8 from peripheral blood mononuclear cells of Korean domestic pig (Sus scrofa domestica). The newly cloned IFNα8 amino acid sequence from Korean domestic pig shares 98.4% identity with the known porcine IFNα8 in databank. The recombinant porcine IFNα8 showed potent antiviral activity and protected bovine Madin-Darby bovine kidney epithelial (MDBK) cells from the cytopathic effect of vesicular stomatitis virus, but it failed to protect human Wistar Institute Susan Hayflick (WISH) cells and canine Madin-Darby canine kidney epithelial-like (MDCK) cells. The present study demonstrates species specific antiviral activity of porcine IFNα8.
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Affiliation(s)
- Eunhye Kim
- Laboratory of Cytokine Immunology, Department of Biomedical Science and Technology, Konkuk University, Seoul 05029, Korea.,Collage of Veterinary Medicine, Konkuk University, Seoul 05029, Korea
| | - Hyunjhung Jhun
- Laboratory of Cytokine Immunology, Department of Biomedical Science and Technology, Konkuk University, Seoul 05029, Korea.,Research Group of Nutraceuticals for Metabolic Syndrome, Korea Food Research Institute, Jeonbuk 55365, Korea
| | - Joohee Kim
- Laboratory of Cytokine Immunology, Department of Biomedical Science and Technology, Konkuk University, Seoul 05029, Korea.,Department of Clinical Pathology, Kyungdong University Medical Campus, Wonju-si, Gangwondo 24695, Korea
| | - Unjoo Park
- Laboratory of Cytokine Immunology, Department of Biomedical Science and Technology, Konkuk University, Seoul 05029, Korea
| | - Seunghyun Jo
- Laboratory of Cytokine Immunology, Department of Biomedical Science and Technology, Konkuk University, Seoul 05029, Korea.,Collage of Veterinary Medicine, Konkuk University, Seoul 05029, Korea
| | - Areum Kwak
- Laboratory of Cytokine Immunology, Department of Biomedical Science and Technology, Konkuk University, Seoul 05029, Korea.,Collage of Veterinary Medicine, Konkuk University, Seoul 05029, Korea
| | - Sinae Kim
- Laboratory of Cytokine Immunology, Department of Biomedical Science and Technology, Konkuk University, Seoul 05029, Korea.,Collage of Veterinary Medicine, Konkuk University, Seoul 05029, Korea
| | - Tam T Nguyen
- Laboratory of Cytokine Immunology, Department of Biomedical Science and Technology, Konkuk University, Seoul 05029, Korea.,Collage of Veterinary Medicine, Konkuk University, Seoul 05029, Korea
| | - Yongsun Kang
- Laboratory of Cytokine Immunology, Department of Biomedical Science and Technology, Konkuk University, Seoul 05029, Korea.,Collage of Veterinary Medicine, Konkuk University, Seoul 05029, Korea
| | - Insoo Choi
- Collage of Veterinary Medicine, Konkuk University, Seoul 05029, Korea
| | - Joongbok Lee
- Collage of Veterinary Medicine, Konkuk University, Seoul 05029, Korea
| | - Heijun Kim
- Laboratory of Cytokine Immunology, Department of Biomedical Science and Technology, Konkuk University, Seoul 05029, Korea.,Kulf Corporation, Namyangju-si, Gyeonggi-do 12241, Korea
| | - Younghyun Kim
- Kulf Corporation, Namyangju-si, Gyeonggi-do 12241, Korea
| | - Siyoung Lee
- Laboratory of Cytokine Immunology, Department of Biomedical Science and Technology, Konkuk University, Seoul 05029, Korea.,YbdYbiotech Research Center, Seoul 08589, Korea
| | - Soohyun Kim
- Laboratory of Cytokine Immunology, Department of Biomedical Science and Technology, Konkuk University, Seoul 05029, Korea.,Collage of Veterinary Medicine, Konkuk University, Seoul 05029, Korea
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Viana J, Dorea M, Siqueira L, Arashiro E, Camargo L, Fernandes C, Palhão M. Occurrence and characteristics of residual follicles formed after transvaginal ultrasound-guided follicle aspiration in cattle. Theriogenology 2013; 79:267-73. [DOI: 10.1016/j.theriogenology.2012.08.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2012] [Revised: 08/16/2012] [Accepted: 08/17/2012] [Indexed: 10/27/2022]
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6
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Amino acid differences in interferon-tau (IFN-τ) of Bos taurus Coreanae and Holstein. Cytokine 2012; 59:273-9. [PMID: 22578803 DOI: 10.1016/j.cyto.2012.03.031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Revised: 09/14/2011] [Accepted: 03/29/2012] [Indexed: 11/21/2022]
Abstract
Interferons (IFNs) are commonly grouped into type I and type II IFN. Type I IFNs are known as antiviral IFNs including IFN-α, IFN-β, and IFN-ω whereas type II IFN is referred to immune IFN and IFN-γ is only member of the type II IFN. Type I IFNs are induced by virus invading however type II IFN is produced by mitogenic or antigenic stimuli. IFN-τ was first identified in ruminant ungulates as a pregnancy recognition hormone, trophoblastin. IFN-τ constitutes a new class of type I IFN, which possesses the common features of type I IFN, such as the ability to prevent viral infection and to limit cell proliferation. In addition, IFN-τ is unique in that it is induced by pregnancy unlike other type I IFNs. We cloned Bos taurus (B. T.) Coreanae IFN-τ from peripheral blood mononuclear cells. The amino acid sequence of B. T. Coreanae IFN-τ shares only 90.3% identity with that of Holstein dairy cow. Recombinant B. T. Coreanae and Holstein IFN-τ proteins were expressed in Escherichia coli and the antiviral activity of IFN-τ proteins were examined. Both recombinant proteins were active and protected human WISH and bovine MDBK cells from the cytopathic effect of vesicular stomatitis virus. The recombinant IFN-τ protein of B. T. Coreanae and Holstein properly induced the expression of antiviral genes including 2',5'-oligoadenylate synthetase (OAS) and Mx GTPase 1 (Mx-1).
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7
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EL-Sherry T, Matsui M, Kida K, Miyamoto A, Megahed G, Shehata S, Miyake YI. Ovarian stimulation with follicle-stimulating hormone under increasing or minimal concentration of progesterone in dairy cows. Theriogenology 2010; 73:488-95. [DOI: 10.1016/j.theriogenology.2009.09.031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2009] [Revised: 09/10/2009] [Accepted: 09/27/2009] [Indexed: 11/30/2022]
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8
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Effect of follicular wave synchronization on in vitro embryo production in heifers. Anim Reprod Sci 2010; 117:201-7. [DOI: 10.1016/j.anireprosci.2009.04.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Revised: 04/14/2009] [Accepted: 04/27/2009] [Indexed: 11/22/2022]
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9
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Synchronization of follicular wave emergence prior to superovulation in Bactrian camel (Camelus bactrianus). Theriogenology 2008; 69:491-500. [DOI: 10.1016/j.theriogenology.2007.10.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2007] [Revised: 10/25/2007] [Accepted: 10/29/2007] [Indexed: 11/20/2022]
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10
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Ghanem N, Hölker M, Rings F, Jennen D, Tholen E, Sirard MA, Torner H, Kanitz W, Schellander K, Tesfaye D. Alterations in transcript abundance of bovine oocytes recovered at growth and dominance phases of the first follicular wave. BMC DEVELOPMENTAL BIOLOGY 2007; 7:90. [PMID: 17662127 PMCID: PMC1976425 DOI: 10.1186/1471-213x-7-90] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2007] [Accepted: 07/27/2007] [Indexed: 11/10/2022]
Abstract
Background Oocyte developmental competence is highly affected by the phase of ovarian follicular wave. Previous studies have shown that oocytes from subordinate follicles recovered at growth phase (day 3 after estrus) are developmentally more competent than those recovered at dominance phase (day 7 after estrus). However, the molecular mechanisms associated with these differences are not well elucidated. Therefore, the objective of this study was to investigate transcript abundance of bovine oocytes retrieved from small follicles at growth and dominance phases of the first follicular wave and to identify candidate genes related to oocyte developmental competence using cDNA microarray. Results Comparative gene expression analysis of oocytes from growth and dominance phases and subsequent data analysis using Significant Analysis of Microarray (SAM) revealed a total of 51 differentially regulated genes, including 36 with known function, 6 with unknown function and 9 novel transcripts. Real-time PCR has validated 10 transcripts revealed by microarray analysis and quantified 5 genes in cumulus cells derived from oocytes of both phases. The expression profile of 8 (80%) transcripts (ANAXA2, FL396, S100A10, RPL24, PP, PTTG1, MSX1 and BMP15) was in agreement with microarray data. Transcript abundance of five candidate genes in relation to oocyte developmental competence was validated using Brilliant Cresyl Blue (BCB) staining as an independent model. Furthermore, localization of mRNA and protein product of the candidate gene MSX1 in sections of ovarian follicles at days 0, 1, 3 and 7 of estrous cycle showed a clear fluorescent signal in both oocytes and cumulus cells with higher intensity in the former. Moreover, the protein product was detected in bovine oocytes and early cleavage embryos after fertilization with higher intensity around the nucleus. Conclusion This study has identified distinct sets of differentially regulated transcripts between bovine oocytes recovered from small follicles at growth and dominance phases of the first follicular wave. The validation with independent model supports our notion that many of the transcripts identified here may represent candidate genes associated with oocyte developmental competence. Further specific functional analysis will provide insights into the exact role of these transcripts in oocyte competence and early embryonic development.
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Affiliation(s)
- Nasser Ghanem
- Institute of Animal Science, Animal Breeding and Husbandry Group, University of Bonn, 53115 Bonn, Germany
| | - Michael Hölker
- Institute of Animal Science, Animal Breeding and Husbandry Group, University of Bonn, 53115 Bonn, Germany
| | - Franca Rings
- Institute of Animal Science, Animal Breeding and Husbandry Group, University of Bonn, 53115 Bonn, Germany
| | - Danyel Jennen
- Institute of Animal Science, Animal Breeding and Husbandry Group, University of Bonn, 53115 Bonn, Germany
| | - Ernst Tholen
- Institute of Animal Science, Animal Breeding and Husbandry Group, University of Bonn, 53115 Bonn, Germany
| | - Marc-André Sirard
- Centre de Recherche en Biologie de la Reproduction, Université Laval, Département des Sciences Animales, Pav. Comtois, Laval, Sainte-Foy, Québec, G1K 7P4, Canada
| | - Helmut Torner
- Research Institute for Biology of Farm Animals, Wilhelm-Stahl-Allee 2, 18196 Dummerstorf, Germany
| | - Wilhelm Kanitz
- Research Institute for Biology of Farm Animals, Wilhelm-Stahl-Allee 2, 18196 Dummerstorf, Germany
| | - Karl Schellander
- Institute of Animal Science, Animal Breeding and Husbandry Group, University of Bonn, 53115 Bonn, Germany
| | - Dawit Tesfaye
- Institute of Animal Science, Animal Breeding and Husbandry Group, University of Bonn, 53115 Bonn, Germany
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Landaeta-Hernández AJ, Giangreco M, Meléndez P, Bartolomé J, Bennet F, Rae DO, Hernández J, Archbald LF. Effect of biostimulation on uterine involution, early ovarian activity and first postpartum estrous cycle in beef cows. Theriogenology 2004; 61:1521-32. [PMID: 15036982 DOI: 10.1016/j.theriogenology.2003.09.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2003] [Accepted: 09/01/2003] [Indexed: 10/26/2022]
Abstract
The objective was to determine the effect of biostimulation (bull-exposure) on uterine involution (UI), plasma progesterone concentration (P4), size of largest follicle (LF), number of follicles larger than 5 mm ( F > or = 5 ), presence of fluid in uterine lumen (PF), presence of luteal tissue (LT), and length of the first estrous cycle postpartum (LEC). Ninety Angus cows with calves were allocated by parity and body frame into three groups (30 per group) 1 week postpartum. Two groups were exposed to bulls (BE) and one non-exposed group (NE) served as a control. Data were collected during weekly sessions of palpation per rectum, ultrasonography and bleeding on a subgroup of 30 cows (10 cows per group) for 6 weeks, and permanent surveillance of estrus with HeatWatch on all 90 cows. There were no significant differences between BE and NE cows for UI ( 17.1+/-1.1 days versus 20.1+/-1.6 days), LF ( 9.5+/-1.7 mm versus 11.0+/-2.4 mm), F > or = 5 ( 1.20+/-0.3 versus 1.47+/-0.09 ), and PF. However, LT was detected in more BE than NE cows (13 versus 2; P<0.001 ). Overall differences in P4 were found between BE and NE cows with detected LT ( 2.00+/-0.3 ng/ml versus 1.05+/-0.4 ng/ml, respectively; P<0.05 ). More BE cows resumed reproductive cyclicity with estrous cycles normal in length compared with NE cows (16/30, 53%; 16/30, 53%; and 8/30, 26.6%, for the two BE groups and the NE group, respectively; P<0.01 ). In conclusion, BE hastened luteal function but did not affect uterine involution.
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Affiliation(s)
- A J Landaeta-Hernández
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida. Gainesville, FL 32610-0136, USA
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Abstract
At birth the ovaries of mammalian females contain a finite store of primordial follicle oocytes. Each oocyte and its surrounding follicle cells share a communication system, the gap junction network, which facilitates the transfer of signals as well as nutrients in to and out off the oocyte and between follicle cells. The connexin family of proteins form the building blocks of this communication network, their expression is specific to the differentiated state of the granulose cell and the stage of folliculogenesis. Factors such as the c-kit receptor and its ligand, IGF-I, IGF-I receptors and the IGF binding proteins, members of the transforming growth factor beta (TGFbeta) family, in particular, some of the bone morphogenetic proteins, play prominent roles in oogenesis, primordial follicle activation and subsequent follicle/oocyte development culminating in oocyte ovulation. The oocyte undergoes a progressive series of morphological modifications as it grows and proceeds through the different stages of development. These structural rearrangements facilitate the increasing energy and nucleic acid synthesis requirements of the developing oocyte and are a prerequisite to the oocytes achievement of meiotic and embryo developmental competence. Several factors determine the ultimate competence of the oocyte, these have been investigated and attempts made to mimic these conditions in vitro. The complexity of the orchestration of the events that control oocyte growth and ultimate acquisition of developmental competence is under continuous investigation. The present review describes some of the findings to date.
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Affiliation(s)
- Trudee Fair
- Department of Animal Science and Production and The Conway Institute for Biomedical and Biomolecular Research, University College Dublin, Lyons Research Farm, Newcastle, County Dublin, Ireland.
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Abstract
In the present short review superovulation treatments commonly used for Bos taurus and/or Bos indicus will be addressed with emphasis in recent superstimulation protocols associated with pharmacological manipulation of the follicular dynamics to improve donor management and potentially embryo yield. Results obtained after superovulation treatments in which the time of LH surge is selectively delayed as an attempt to improve embryo yield are presented and discussed.
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Affiliation(s)
- C M Barros
- Departamento de Farmacologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, São Paulo, Brazil.
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Ali A, Lange A, Gilles M, Glatzel PS. Morphological and functional characteristics of the dominant follicle and corpus luteum in cattle and their influence on ovarian function. Theriogenology 2001; 56:569-76. [PMID: 11572438 DOI: 10.1016/s0093-691x(01)00589-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Predicting the functional activity of a dominant follicle (DF) and corpus luteum (CL) might be important before starting a superovulation regime or a synchronization program. The DF and CL were characterized morphologically by using ultrasonography and were characterized functionally by estimating the estradiol-17beta/progesterone (E2/P4) ratio. Their influence on ovarian function was estimated through their ability to ovulate at different stages of development in response to PGF2alpha-application. A total of 47 Holstein Friesian (35 cows and 12 heifers) were used in two experiments. In Experiment 1, 25 animals were examined by daily transrectal palpation and ultrasonography to follow the morphological development of the DF. The status of the DF was categorized into 3 groups (A1, B1, C1). The A1 group (n=7) contained animals with DF in the growing phase or in early static growth phase for less than 3 days. Group B1 (n=13) included animals with DF in static growth phase for 3 to 4 days, while Group C1 (n=5) comprised animals with DF keeping a plateau for more than 4 days or animals with DF in the regression phase. The DF were aspirated transvaginally and the follicular fluid (FF) was analyzed for E2 and P4. In Experiment 2, 22 animals were included. As in Experiment 1, the animals were classified into three groups (A2, n=10; B2, n=5; C2, n=7). They were treated by a single dose of PGF2alpha (25 mg, i.m.) between Days 8 and 12 of the cycle. Results showed that luteolyses occurred in all animals. The DF, which were in growing or in early static growth phase < 3 days were always E2-dominant (E2 > P4) and ovulated after PGF2alpha-application in 6/8 of cases and persisted in 2 (Group A2). The DF persisting > 4 days or that had been in regression were always P4-dominant. This type of DF regressed after PGF2alpha-application (Group C2). The DF in early static growth phase for 3 to 4 days in 5/13 cases were E2-dominant and in 8/13 cases were P4-dominant. This type of DF ovulated in 3/5 cases and regressed in 2/5 cases after PGF2alpha-application (Group B2). These results suggest that the DF is morphologically and functionally defined as long as the DF is in the growing or early static growth phase (A1, A2) for at least 2 days or if the DF is in regression (C1, C2). However, when the DF is in the static growth phase for 3 or 4 days (B1, B2), their morphological and functional characteristics are different. The CL controlls ovulation in the A and C groups and plays an abettor's roll in the B-group.
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Affiliation(s)
- A Ali
- Department of Theriogenology, Faculty of Veterinary Medicine, Assiut University, Egypt
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15
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Driancourt MA. Regulation of ovarian follicular dynamics in farm animals. Implications for manipulation of reproduction. Theriogenology 2001; 55:1211-39. [PMID: 11327681 DOI: 10.1016/s0093-691x(01)00479-4] [Citation(s) in RCA: 142] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In this review, the main features of folliculogenesis are summarized and compared among species. In the past few years, ultrasonography has clarified follicle growth patterns, and our understanding of follicle maturation has improved considerably. As the follicles develop towards the ovulatory stage, three features appear to be highly conserved across all species: 1) the sequence of events (recruitment, selection and dominance); 2) the sequential need for gonadotropins (FSH for recruitment, LH for dominance) and 3) the large variability of numerical parameters (number of waves per cycle, number of follicles per wave) as well as temporal requirements (time of selection, duration of dominance). In addition, specific follicles may also have variable gonadotropin requirements (thresholds). When patterns of follicle development at different physiological states are compared across species, follicular waves were detected in cattle, sheep and horses and during the prepubertal period in swine, suggesting that ovaries of all species operate on a wave basis unless they are prevented from doing so. Efficient estrus control treatments should have the ability to affect 1) the wave pattern by preventing the development of persistent dominant follicles containing aging oocytes, and 2) the recruitment of the future ovulatory follicle whatever the stage of the wave at the time of treatment. This would allow synchronous ovulation of a growing dominant follicle. Manipulation of the luteal phase follicular waves after mating or AI may also optimize fertility. Superovulation is still an efficient technique to obtain progeny from genetically valuable females. Administration of exogenous gonadotropins acts to reveal the underlying ovarian variability. Ovarian response of each female depends on the number of gonado-sensitive follicles present at the time when treatment is initiated. Identification of the number of such follicles for each female would improve efficacy of superovulation, by allocating potential nonresponders to other techniques (OPU/FIV). One of the main components of the within female response to superovulation is the stage of the wave when gonadotropins are injected. Treatment in the absence of a dominant follicle ensures a response close to the female's specific maximum. The development of practical approaches to achieve this still requires further research.
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Kim IH, Son DS, Yeon SH, Choi SH, Park SB, Ryu IS, Suh GH, Lee DW, Lee CS, Lee HJ, Yoon JT. Effect of dominant follicle removal before superstimulation on follicular growth, ovulation and embryo production in Holstein cows. Theriogenology 2001; 55:937-45. [PMID: 11291916 DOI: 10.1016/s0093-691x(01)00455-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
This study was to investigate whether removing the dominant follicle 48 h before superstimulation influences follicular growth, ovulation and embryo production in Holstein cows. After synchronization, ovaries were scanned to assess the presence of a dominant follicle by ultrasonography with a real-time linear scanning ultrasound system on Days 4, 6 and 8 of the estrus cycle (Day 0 = day of estrus). Twenty-six Holstein cows with a dominant follicle were divided into 2 groups in which the dominant follicle was either removed (DFR group, n=13) by ultrasound-guided follicular aspiration or left intact (control group, n=13) on Day 8 of the estrus cycle. Superovulation treatment was initiated on Day 10. All donors were superovulated with injections of porcine FSH (Folltropin) twice daily with constant doses (total: 400 mg) over 4 d. On the 6th and 7th injections of Folltropin, 30 mg and 15 mg of PGF2alpha (Lutalyse) were given. Donors were inseminated twice at 12 h and 24 h after the onset of estrus. Embryos were recovered on Day 6 or 7 after AI. During superstimulation, the number of follicles 2 to 5 mm (small), 6 to 9 mm (medium) and > or = 10 mm (large) was determined by ultrasonography on a daily basis. At embryo recovery, the number of corpora lutea (CL) was also determined by ultrasonography and blood samples were collected for analysis of progesterone concentration. Follicular growth during superstimulation was earlier in the DFR group than in the control group. The number of medium and large follicles was greater (P < 0.01) in the DFR group than in the control group on Days 1 to 2 and Days 3 to 4 of superstimulation, respectively. The numbers of CL (9.6+/-1.1 vs 6.1+/-0.9) and progesterone concentration (30.9+/-5.4 vs 18.6+/-3.5 ng/mL) were greater (P < 0.05) in the DFR group than in the control group, respectively. The numbers of total ova (7.7+/-1.3 vs 3.9+/-1.0) and transferable embryos (4.6+/-0.9 vs 2.3+/-0.8) were also greater (P < 0.05) in the DFR group than in the control group, respectively. It is concluded that the removal of the dominant follicle 48 h before superstimulation promoted follicular growth, and increased ovulation and embryo production in Holstein cows.
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Affiliation(s)
- I H Kim
- National Livestock Research Institute, RDA, Cheonan, Chungnam, Korea
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17
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Diaz T, Pancarci SM, Drost M, Schmitt EJ, Ambrose JD, Fredriksson WE, Thatcher WW. Effects of the persistent dominant follicle on the ability of follicle stimulating hormone to induce follicle development and ovulatory responses. J Dairy Sci 2001; 84:88-99. [PMID: 11210054 DOI: 10.3168/jds.s0022-0302(01)74456-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Three experiments were conducted to evaluate the effect of an induced first wave persistent dominant follicle on folliculogenesis and ovulatory responses induced by FSH. On d 6 of a synchronized estrous cycle (d 0 = estrus), cows were treated with a Syncromate-B implant and two injections of PGF2, (25 mg, 0700 h; 15 mg, 1900 h, i.m.). Cows in the control group retained a first-wave persistent dominant follicle, but in the aspirated group, the first-wave dominant follicle was removed via transvaginal aspiration on d 10 (d 0 = estrus). Beginning on d 12, cows received 32 mg of FSH-P i.m. in decreasing doses at 12-h intervals over a 4-d period. On d 15, the Syncromate-B implant was removed, and cows were ovariectomized (experiment 1, n = 8) or inseminated (experiment 2, n = 11) at 10 and 22 h after the onset of estrus. Cows in experiment 3 received a used controlled intravaginal drug releasing (CIDR) device and two injections of PGF2alpha (25 mg, 0700 h; 15 mg, 1900 h; i.m.) on d 6. On d 8, the first-wave dominant follicle was aspirated (n = 6) or left intact (n = 5), and FSH treatment was initiated (20 mg of Folltropin in decreasing doses at 12-h intervals over a 4-d period), and on d 10 the used CIDR device was removed from all cows. Ovarian follicle size and number were examined daily by ultrasonography from d 5 of the estrous cycle. The persistent dominant follicle increased in size from 10.7 mm on d 5 to 15.4 mm on d 10 (experiments 1 and 2), and from 9 mm on d 5 to 20.4 mm on d 11 (experiment 3). From d 11 to 14, the number of class 1 (2 to 5 mm) follicles was lower in the aspirated group than in the control group; the number of class 2 (6 to 9 mm) follicles was higher on d 12 and 13 for the aspirated group (experiments 1 and 2). The number of class 3 (> or =10 mm) follicles was higher in the aspirated group on d 14 to 16, but the same on d 17. Ovarian and embryo responses to superovulation did not differ between groups. In experiment 3, the numbers of class 1, 2, and 3 follicles, as well as ovarian and embryo responses following ovulation did not differ between groups. Initiation of exogenous FSH treatment appears to override any systemic inhibitory effect that a persistent dominant follicle may be exerting at the pituitary and possibly the ovary.
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Affiliation(s)
- T Diaz
- Department of Dairy and Poultry Sciences, and University of Florida, Gainesville 32611-0920, USA
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18
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Buratini J, Price CA, Visintin JA, Bó GA. Effects of dominant follicle aspiration and treatment with recombinant bovine somatotropin (BST) on ovarian follicular development in nelore (Bos indicus) heifers. Theriogenology 2000; 54:421-31. [PMID: 11051325 DOI: 10.1016/s0093-691x(00)00359-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Follicle ablation has been recognized as an efficient method of follicular wave synchronization. Treatment with recombinant bovine somatotropin (BST) has been shown to enhance follicular development in Bos taurus. This experiment assessed the effects of these treatments in Nelore (B. indicus) heifers. Eight cycling Nelore heifers were randomly assigned to 3 different treatments. On Day 2 of a synchronized cycle (Day 0 = day of ovulation), heifers assigned to Treatments 1 and 2 received 2 mL of saline, whereas heifers assigned to Treatment 3 received 320 mg of BST. On Day 5, the first-wave dominant follicle was ablated by ultrasound-guided transvaginal aspiration in heifers in Treatments 2 and 3, and all heifers received an injection of prostaglandin on Day 11. Aspiration of the dominant follicle advanced and synchronized (P < 0.05) the day of second-wave emergence (6.9 +/- 0.1 vs. 8.4 +/- 0.4) and the day of the pre-wave FSH peak (6.0 +/- 0.0 vs. 6.9 +/- 0.4), and increased FSH peak concentrations (381 +/- 21 vs. 292 +/- 30; pg/mL; P < 0.01). Recombinant bovine somatotropin treatment caused a two-fold increase in plasma insulin-like growth factor-I (IGF-I) concentrations (P < 0.001) and resulted in a 36% increase in the number of small follicles (<5 mm; P < 0.001) compared with saline-treated heifers. In summary, in agreement with previous reports on B. taurus, dominant follicle aspiration synchronized ovarian follicular development, and BST treatment increased peripheral concentrations of IGF-I in Nelore heifers. Recombinant bovine somatotropin also increased the number of small follicles, but this response appeared to be inferior to that reported for B. taurus.
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Affiliation(s)
- J Buratini
- Department of Animal Reproduction, Faculty of Veterinary Medicine, University of São Paulo, Brazil.
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19
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Garcia A, van der Weijden GC, Colenbrander B, Bevers MM. Monitoring follicular development in cattle by real-time ultrasonography: a review. Vet Rec 1999; 145:334-40. [PMID: 10530882 DOI: 10.1136/vr.145.12.334] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The application of real-time ultrasonography to monitoring ovarian function in mammals has advanced the understanding of follicular dynamics and its regulation. Follicular development is a wave-like sequence of organised events. The waves consist of the synchronous growth of small (4 to 5 mm) antral follicles, followed by the selection and growth of one dominant follicle which achieves the largest diameter and suppresses the growth of the subordinate follicles. In the absence of luteal regression, the dominant follicle eventually regresses (becomes atretic) and a new follicular wave begins. The dominant follicle regulates the growth of the subordinate follicles, because the appearance of the next wave is accelerated if the dominant follicle is ablated, and delayed if the lifespan of the dominant follicle is prolonged. During bovine oestrous cycles, two or three successive waves emerge, on average, on the day of ovulation (day 0) and day 10 for two-wave cycles, and on days 0, 9 and 16 for three-wave cycles. During the oestrous cycle there are thus two or three successive dominant follicles, and the last of these ovulates. Ovarian folliculogenesis is a complex process involving interactions between pituitary gonadotrophins, ovarian steroids and non-steroidal factors. Subtle changes in the hormonal milieu regulate folliculogenesis and the emergence of a follicular wave is preceded by a small increase in the concentration of plasma follicle-stimulating hormone. The mechanisms that promote the selection of a dominant follicle have not been elucidated, but considerable progress has been made in understanding follicular development and its regulation. Most treatments designed to control the development of follicular waves have been based on the physical or hormonal removal of the suppressive effect of the dominant follicle, and the consequent controlled induction of the emergence of a new follicular wave. The studies reviewed here describe current methods for regulating the bovine ovarian cycle, interesting models for future studies, and information that may be used for improving reproductive efficiency.
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Affiliation(s)
- A Garcia
- Department of Herd Health and Reproduction, Faculty of Veterinary Medicine, University of Utrecht, The Netherlands
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20
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Hagemann LJ, Beaumont SE, Berg M, Donnison MJ, Ledgard A, Peterson AJ, Schurmann A, Tervit HR. Development during single IVP of bovine oocytes from dissected follicles: interactive effects of estrous cycle stage, follicle size and atresia. Mol Reprod Dev 1999; 53:451-8. [PMID: 10398421 DOI: 10.1002/(sici)1098-2795(199908)53:4<451::aid-mrd11>3.0.co;2-3] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Previous work suggests that a number of factors such as follicle size, day of estrous cycle, and level of atresia influence the developmental potential of bovine oocytes in vitro. To understand better the interactions of these factors, 1299 follicles > or =3 mm in diameter were dissected from ovaries of synchronized dairy cows on four days (d2, d7, d10, or d15) during the estrous cycle. The oocyte from each follicle was collected and matured, fertilized, and cultured singly to d8 (d0 of culture = IVF). Control follicles (302) were similarly dissected and processed from an ovary pair randomly collected from the abattoir on each slaughter day. Results showed that development to blastocyst was greater in oocytes collected during phases of follicular growth (d2 and d10) than those collected during phases of follicular dominance (d7 and d15; 44.8% vs. 36.0%, respectively: P < 0.001) over all follicle size categories (3-5 mm, 6-8 mm, 9-12 mm and > or =13 mm). Oocyte competence tended to increase with increasing follicle size (P < 0.1). Follicular cells from follicles containing an oocyte that developed to morula or greater by d8 (484 samples) were analyzed by flow cytometry to measure the level of apoptosis. Results showed an increase in mean percent apoptotic cells in subordinate follicles (18.65 +/- 0.86 over all size categories), particularly those of medium size (25.55 +/- 2.2 for 6-8 mm size follicles; P < 0.001), during the dominance phase compared to growth phase (9.25 +/- 0.95 over all sizes; P < 0.05). These results show a significant affect of the stage of estrous cycle on both oocyte competence and levels of follicular atresia.
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Affiliation(s)
- L J Hagemann
- AgResearch, Dairy & Beef Division, Ruakura Research Centre, Hamilton, New Zealand.
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21
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Abstract
As the oocyte grows within the follicle, a number of factors influence its health and developmental competence. These factors include follicle size, day of estrous cycle, level of atresia and influence of other follicles such as the dominant follicle. Follicles were dissected from ovaries of synchronized dairy cows on four days during the estrous cycle, and the oocyte from each follicle collected, matured, fertilized and cultured singly until Day 8. Development to blastocyst was greater in oocytes collected during phases of follicular growth than those collected during phases of follicular dominance (P<0.001) over all follicle size categories. Oocyte competence tended to increase with increasing follicle size (P<0.1). Follicular cells analyzed by flow cytometry showed an increase in proportion of apoptotic cells in subordinate follicles during the dominant phase compared to growth phase (P<0.05). Thus, the dominant follicle on both oocyte competence and levels of atresia. Further studies on the effect of dominance has shown that lactate production in cumulus-oocyte-complexes (COCs) from medium-sized follicles collected during a dominance phase and small follicles collected during a growth phase are no different from other follicles, despite having significantly lower uptake of glucose (P<0.1). Thus, COCs from different follicle subclasses differ in their nutrient requirements, and current IVM technology needs further improvement to better assist those oocytes that are developmentally challenged.
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22
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D'Occhio MJ, Jillella D, Lindsey BR. Factors that influence follicle recruitment, growth and ovulation during ovarian superstimulation in heifers: opportunities to increase ovulation rate and embryo recovery by delaying the exposure of follicles to LH. Theriogenology 1999; 51:9-35. [PMID: 10729059 DOI: 10.1016/s0093-691x(98)00228-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The outcome of ovarian follicular superstimulation protocols in heifers is influenced by the number of follicles that are stimulated to grow and the number induced to ovulate. At present, only a proportion of the follicles that are stimulated to grow progress to ovulation. The argument is developed in this review that failure of some of these follicles to ovulate may be due not to an intrinsic deficiency but rather to their relatively small size when the FSH treatment is initiated. Consequently, these follicles do not have the opportunity to undergo full maturation within the time frame of a conventional superstimulation protocol Based on this argument, we propose that delaying the LH surge would allow for completion of maturation by a greater number of follicles, resulting in an increased ovulation rate and in recovery of a greater number of viable embryos.
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Affiliation(s)
- M J D'Occhio
- Animal Sciences and Production Group, Central Queensland University, Rockhampton, Australia.
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23
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Yaakub H, Duffy P, O'Callaghan D, Boland MP. Effect of timing of oestradiol benzoate injection relative to gonadotropin treatment on superovulatory response, and on embryo yield and quality in beef heifers. Anim Reprod Sci 1998; 52:191-204. [PMID: 9783992 DOI: 10.1016/s0378-4320(98)00106-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Variation in superovulatory responses in cattle may be related to the stage of follicular growth at the time of gonadotropin treatment. Waves of follicle growth are regulated by both follicle-stimulating hormone (FSH) and oestradiol. The objective of experiment 1 was to determine the dynamics of follicle wave emergence and the relationship with FSH and oestradiol concentrations, after treatment of heifers with oestradiol benzoate (ODB) in the presence of an intravaginal progesterone-releasing device (CIDR-B). Experiment 2 examined the superovulatory response, embryo yield and quality following treatment with porcine follicle-stimulating hormone (pFSH) at different times relative to ODB injection. In experiment 1, 28 beef heifers were treated with a CIDR for 9 days and allocated at random to one of four groups to receive either: (I) CIDR only, or 5 mg ODB given as a single intramuscular injection at (II) day 0 (d0); (III) day 1.5 (d1.5); or (IV) day 3 (d3) post CIDR insertion. Ovaries were examined using daily ultrasound and blood samples were collected twice daily for 11 days. In experiment 2, 96 heifers were treated with a CIDR and 5 mg ODB as in experiment 1, and were allocated using a 4 x 3 factorial design plan to a superovulation programme using three doses (400 IU; 600 IU; 800 IU) of pFSH. FSH was given for 4 days at 12-h intervals beginning 6.5 days after CIDR insertion. Heifers received prostaglandin analogue 12 h before CIDR removal and were inseminated (AI) at 48 and 60 h post CIDR withdrawal and embryos were recovered 7 days after AI. In experiment 1, the interval from CIDR insertion to follicle wave emergence (FWE) was longer (P < 0.05) in heifers treated with ODB at d1.5 (5.4 +/- 0.4 days) and d3 (5.1 +/- 0.6 days) compared to heifers treated with CIDR only (2.4 +/- 0.4 days). On the basis of time to proposed injection of pFSH heifers would have had follicle emergence 4.4, 2.3, 1.5 and 1.4 days prior to pFSH for groups I, II, III and IV, respectively. In experiment 2, heifers treated with ODB at d1.5 had a higher (P < 0.05) superovulatory response (18.2 +/- 1.7) than heifers treated at d3 (12.8 +/- 1.7), but superovulatory response in both groups did not differ (P > 0.05) from heifers treated at d0 (14.4 +/- 2.0) or with CIDR only (15.0 +/- 1.8). There were fewer (P < 0.05) freezable-grade embryos recovered from heifers treated with ODB at d0 (1.5 +/- 0.7) and d3 (2.1 +/- 0.5) compared to heifers treated at d1.5 (3.0 +/- 0.6) or in heifers treated with CIDR only (3.4 +/- 0.7). Increasing the dose of pFSH caused a linear increase in the superovulatory response (11.7 +/- 1.0, 15.8 +/- 1.4 and 18.0 +/- 1.9) and in the number of embryos recovered (5.8 +/- 0.9, 7.0 +/- 0.8 and 9.1 +/- 1.0) for 400 IU, 600 IU and 800 IU, respectively. In conclusion, heifers treated with ODB had wide variation in time to follicle wave emergence and there was not a consistent beneficial effect of pretreatment with ODB on embryo yield and quality following superovulation.
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Affiliation(s)
- H Yaakub
- Faculty of Agriculture, University College Dublin, Belfield, Ireland
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