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Ginther OJ. Switching of follicle destiny so that the second largest follicle becomes dominant in monovulatory species. Theriogenology 2021; 171:147-154. [PMID: 34058507 DOI: 10.1016/j.theriogenology.2021.05.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 04/27/2021] [Accepted: 05/02/2021] [Indexed: 11/15/2022]
Abstract
During an ovulatory follicular wave in the monovulatory species of heifers, mares, and women, the two largest follicles deviate in diameter at the end of a common follicle growth phase. The largest follicle before deviation becomes the future ovulatory follicle in most ovulatory waves. In 10-30% of the ovulatory waves, the destiny of the two follicles switches just before or at deviation so that the second-largest follicle becomes the future ovulatory follicle, and the largest follicle becomes a subordinate. In FSH-driven switching in heifers, mares, and women, the wave-stimulating FSH surge decreases to a low concentration before the largest follicle has developed the ability to utilize the low concentrations. The concentrations of FSH then increase (mares, women) or cease to decrease (heifers), and the next largest follicle acquires the capability of becoming the future ovulatory follicle. Luteolysis-driven switching has been reported in heifers but not in mares and women. The switching in heifers occurs during ovulatory wave 3 of three wave interovulatory intervals (IOI) when the wave of follicles is in the common growth phase in synchrony with the time of luteolysis. Regression of the CL during the common growth phase of ovulatory wave 3 is accompanied by decreased activity of follicles that are adjacent to the regressing CL but not when follicles and CL are separated or in opposite ovaries. The role of luteolysis in switching in heifers has been tested by treating with PGF2α when the largest follicle of wave 2 was near the end of the common growth phase. Switching in destiny of the largest follicle from the expected future dominant to a future subordinate occurred in most waves (10 of 17) when the largest follicle and regressing CL were in the same ovary and adjacent but not when separated in the same ovary or when in opposite ovaries (0 of 11). The newly selected future ovulatory follicle may develop in the opposite ovary. Thereby, frequency of the contralateral vs ipsilateral relationship between the preovulatory follicle and CL in heifers is greater in three-wave IOI than in two-wave IOI. In summary, the second largest predeviation follicle becomes the postdeviation dominant follicle when the decreasing FSH is out of phase with the largest predeviation follicle in heifers, mares, and women or when luteolysis and predeviation are in synchrony in heifers.
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Affiliation(s)
- O J Ginther
- Eutheria Foundation, Cross Plains, WI, USA; Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI, USA.
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Ginther OJ, Nunes da Silva P, Gomez-León VE, Domingues RR, Inskeep EK. Side of ovulation at each end of two- and three-wave interovulatory intervals and before and after pregnancy in cattle. Anim Reprod Sci 2021; 229:106758. [PMID: 33964763 DOI: 10.1016/j.anireprosci.2021.106758] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 04/22/2021] [Accepted: 04/23/2021] [Indexed: 01/10/2023]
Abstract
The side of ovulation (left ovary, LO; right ovary, RO) and side of the next ovulation were compared between (1) beginning and end of an interovulatory interval (IOI) and beginning and end of consecutive sets of two and three IOI (n = 900 IOI), (2) beginning and end of the IOI for two and three follicular waves per IOI (n = 1300), and (3) beginning of pregnancy and first postpartum ovulation (n = 793). Pairs of sides of ovulation were designated LL (LO and LO), RR, LR, and RL. The frequency of ovulation pairs for two ends of an IOI was not different from two ends of two or three consecutive IOI indicating that differences between LO and RO were more likely inherent than from factors that developed in each IOI. For each end of an IOI or two consecutive IOI, the least frequency (P < 0.05) was for LL (16 %) with no differences among RR, LR, and RL (28 % for each). Frequencies between ipsilateral (LL, RR) and contralateral (LR, RL) ovulations pairs were not different for two-wave IOI (48 % compared with 52 %) but differed (P < 0.0001) for three-wave IOI (32 % compared with 68 %) and for pregnancy/postpartum (34 % compared with 66 %). In pregnancy/postpartum, each pair was different (P < 0.05) from each other: LL (13 %), RR (21 %), LR (30 %), RL (36 %). The lesser frequency for LL than for any of the others for an IOI, consecutive IOI, and pregnancy/postpartum indicated a ubiquity of the small propensity for LO ovulation.
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Affiliation(s)
- O J Ginther
- Eutheria Foundation, Cross Plains, WI, 53528, USA; Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI, 53706, USA.
| | | | - Victor E Gomez-León
- Eutheria Foundation, Cross Plains, WI, 53528, USA; Department of Animal and Dairy Sciences. University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Rafael R Domingues
- Department of Animal and Dairy Sciences. University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - E K Inskeep
- Division of Animal and Nutritional Sciences, West Virginia University, Morgantown, WV, 26506, USA
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Ginther OJ. Selection of side of ovulation by intraovarianism in Bos taurus heifers†. Biol Reprod 2020; 103:711-716. [PMID: 32658294 DOI: 10.1093/biolre/ioaa118] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 06/26/2020] [Accepted: 07/09/2019] [Indexed: 11/14/2022] Open
Abstract
Intraovarianism refers to mechanisms within an ovary that affect the local follicle and luteal dynamics and is well-represented in heifers by greater frequency of ovulation from the right ovary (RO) than the left ovary (LO). On average, the RO has more 6-mm follicles than the LO before one follicle is selected to deviate in diameter and become the future ovulatory follicle. Therefore, the ovulatory follicle is more frequently selected from the RO. More follicles in the RO likely develop before birth as indicated by greater weight of the RO with more 0.3- to 4.8-mm follicles in recently born calves. It has been proposed that differences in intraovarianism between sides are a consequence of differences between sides in the inherent intraovarian angioarchitecture. The frequency of the pair of ovulations at the beginning and end of 900 interovulatory intervals (IOI) was lowest for the left/left (LL) pair (16%) and higher and similar among the RR, LR, and RL pairs (28% each). The lower frequency of LO ovulation was entirely a function of the LL pair as indicated by the lower frequency of the LL than RR pairs without a difference among the RR, LR, and RL pairs. Ovulations from the opposite sides at the beginning and end of an IOI (LR and RL pairs) would not have contributed to a difference in ovulation frequency between LO and RO. In conclusion, the greater frequency of RO (56%) than LO (44%) ovulation was mathematically and functionally a direct consequence of the low frequency of the LL pair of ovulations.
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Affiliation(s)
- O J Ginther
- Eutheria Foundation, Cross Plains, Wisconsin, USA.,Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA
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Ginther O. Intraovarian spatial and vascular harmony between follicles and corpus luteum in monovulatory heifers, mares, and women. Theriogenology 2019; 128:31-39. [DOI: 10.1016/j.theriogenology.2019.01.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 01/18/2019] [Accepted: 01/24/2019] [Indexed: 10/27/2022]
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Ginther O, Dangudubiyyam S. Effect of number of 6-mm predeviation follicles and intraovarian patterns on right-side ovulation in heifers. Anim Reprod Sci 2019; 202:73-79. [DOI: 10.1016/j.anireprosci.2019.01.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 01/30/2019] [Indexed: 11/25/2022]
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Factors affecting side of ovulation in heifers and mares—A comparative study. Anim Reprod Sci 2018; 199:72-78. [DOI: 10.1016/j.anireprosci.2018.10.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 10/20/2018] [Accepted: 10/25/2018] [Indexed: 11/20/2022]
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Martinez IYH, Santos APC, Bottino MP, Orlandi RE, Santos G, Simões LMS, Souza JC, Díaza AMG, Binelli M, Sales JNS. Molecular and endocrine factors involved in future dominant follicle dynamics during the induction of luteolysis in Bos indicus cows. Theriogenology 2018; 111:78-83. [PMID: 29428848 DOI: 10.1016/j.theriogenology.2018.01.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 01/25/2018] [Accepted: 01/29/2018] [Indexed: 10/18/2022]
Abstract
The growth profiles of the future dominant follicle (DF) and subordinate follicle (SF) and the gene expression of the granulosa cells during luteolysis induction in Bos indicus cows were evaluated. Forty cows were synchronized with a progesterone and estradiol based protocol. After synchronization, cows with a corpus luteum (CL) were evaluated by ultrasonography every 12 h, beginning at eight days post ovulation. Cows identified with a follicle of at least 6.0 mm in diameter in the second wave were split into two groups (BD-before follicular deviation and AD-after follicular deviation. In the BD group cows received 500 μg of cloprostenol (a synthetic analogue of prostaglandin F2α) when the DF reached a mean diameter of 7.0 mm (6.5-7.5 mm). In the AD group, cows received 500 μg of cloprostenol when the DF reached a mean diameter of 8.0 mm (7.5-8.5 mm). Cows in both groups were submitted to aspiration of the DF at 96 and 72 h after prostaglandin was given. Follicular aspirations were performed to quantify IGF1R, LHR and PAPPA transcripts in the granulosa cells. The diameter of the DF at the moment of prostaglandin administration (P = 0.001) and the growth rate of the SF (P = 0.05) were greater in the AD group. There was greater abundance of LHR transcripts in BD cows (P = 0.04). The remaining variables tested were similar between the experimental groups (P > 0.05). In conclusion, the induction of luteolysis before follicular deviation does not interfere with dominant follicle dynamics. However, it causes granulosa cell LHR down regulation.
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Affiliation(s)
- I Y H Martinez
- Department of Veterinary Medicine, UFLA, Lavras, Minas Gerais, Brazil
| | - A P C Santos
- Department of Veterinary Medicine, UFLA, Lavras, Minas Gerais, Brazil.
| | - M P Bottino
- Department of Veterinary Medicine, UFLA, Lavras, Minas Gerais, Brazil
| | - R E Orlandi
- Department of Veterinary Medicine, UFLA, Lavras, Minas Gerais, Brazil
| | - G Santos
- Department of Veterinary Medicine, UFLA, Lavras, Minas Gerais, Brazil
| | - L M S Simões
- Department of Veterinary Medicine, UFLA, Lavras, Minas Gerais, Brazil
| | - J C Souza
- Department of Animal Science, UFLA, Lavras, Minas Gerais, Brazil
| | - A M G Díaza
- Department of Animal Reproduction, FMVZ-USP, Pirassununga, São Paulo, Brazil
| | - M Binelli
- Department of Animal Reproduction, FMVZ-USP, Pirassununga, São Paulo, Brazil
| | - J N S Sales
- Department of Veterinary Medicine, UFLA, Lavras, Minas Gerais, Brazil
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Variations in follicle-diameter deviation and a growth spurt in the dominant follicle at deviation in Bos taurus heifers. Anim Reprod Sci 2018; 188:155-164. [DOI: 10.1016/j.anireprosci.2017.11.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 11/21/2017] [Accepted: 11/28/2017] [Indexed: 11/18/2022]
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Ginther O, Domingues R, Siddiqui M, Dangudubiyyam S. Blood flow and echotextural differences between the future dominant and subordinate follicles before the beginning of diameter deviation in heifers. Theriogenology 2017; 100:42-49. [DOI: 10.1016/j.theriogenology.2017.05.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 05/25/2017] [Accepted: 05/30/2017] [Indexed: 11/24/2022]
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Ginther OJ, Siddiqui MAR, Baldrighi JM, Araujo ER. An intraovarian mechanism that enhances the effect of an FSH surge on recovery of subordinate follicles in heifers. Domest Anim Endocrinol 2017; 59:67-74. [PMID: 28002761 DOI: 10.1016/j.domaniend.2016.10.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 09/28/2016] [Accepted: 10/19/2016] [Indexed: 11/26/2022]
Abstract
The effect of the future dominant follicle (DF), corpus luteum (CL), and side (left ovary [LO] and right ovary [RO]) on FSH-induced recovery (increase in diameter) of regressing subordinate follicles was studied in heifers. The DF of wave 2 and the largest subordinate follicle remained intact (controls, n = 14 heifers) or were ablated (n = 14 heifers) on a mean of 13 d postovulation when the DF was ∼10 mm (hour 0). Concentration of FSH (P < 0.0004) and diameter of subordinate follicles (P < 0.0002) decreased between hours -48 to 0 combined for the control and ablation groups. Thereafter, follicle diameter continued to decrease in the controls. Concentration of FSH increased (P < 0.05) and diameter of subordinates began to increase at hour 12 in the ablation group. Follicle-stimulating hormone increased to hour 24 and then returned to the hour 0 concentration by hour 72, completing the induced FSH surge. Concentration of LH began to increase at hour 0 in each group and at a similar rate between groups. Follicle recovery in the ablation group was compared among 8 subgroups as defined by the 2 sides and 4 intraovarian patterns (DF-CL pattern, both structures in same ovary; DF pattern, DF alone; CL pattern, CL alone; and devoid pattern, both structures absent). Follicle diameter increased (P < 0.05) between hours 24 and 48, and diameter at hours 24, 48, 72, and 96 involved a 3-way interaction (P < 0.0001) of pattern, side, and hour. The interaction was similar when diameter of the DF that originated from a recovered subordinate was either included or excluded in the analysis. Diameter of subordinate follicles in the ablation group at hour 96 was greater (P < 0.05) in the DF-CL/RO and DF/RO subgroups than that in the devoid/LO, devoid/RO, and CL/LO subgroups. The DF-CL/LO and CL/RO subgroups were intermediate. For follicles that decreased in diameter before hour 0, a greater (P < 0.05) percentage increased after hour 0 when the ovary contained a DF and was in the RO (DF-CL/RO and DF/RO subgroups) than for the remaining subgroups even after excluding the DF that originated from a subordinate. Results supported the hypotheses that (1) an induced FSH surge can stimulate the recovery of regressing subordinate follicles and (2) recovery of regressing subordinate follicles by FSH involves an intraovarian mechanism. Our interpretation is that the intraovarian mechanism that enhances the stimulatory effect of FSH on recovery of subordinate follicles was effective only in RO and only when it contained a DF.
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Affiliation(s)
- O J Ginther
- Eutheria Foundation, Cross Plains, WI 53528, USA; Pathobiological Sciences Department, School of Veterinary Medicine, University of Wisconsin-Madison, 1656 Linden Dr, Madison, WI 53706, USA.
| | - M A R Siddiqui
- Eutheria Foundation, Cross Plains, WI 53528, USA; Pathobiological Sciences Department, School of Veterinary Medicine, University of Wisconsin-Madison, 1656 Linden Dr, Madison, WI 53706, USA
| | - J M Baldrighi
- Eutheria Foundation, Cross Plains, WI 53528, USA; Pathobiological Sciences Department, School of Veterinary Medicine, University of Wisconsin-Madison, 1656 Linden Dr, Madison, WI 53706, USA
| | - E R Araujo
- Eutheria Foundation, Cross Plains, WI 53528, USA; Pathobiological Sciences Department, School of Veterinary Medicine, University of Wisconsin-Madison, 1656 Linden Dr, Madison, WI 53706, USA
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Temporality of two-way functional coupling between FSH and follicles in heifers. Theriogenology 2016; 86:1645-53. [DOI: 10.1016/j.theriogenology.2015.10.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 09/18/2015] [Accepted: 10/01/2015] [Indexed: 11/23/2022]
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Ginther OJ. The theory of follicle selection in cattle. Domest Anim Endocrinol 2016; 57:85-99. [PMID: 27565235 DOI: 10.1016/j.domaniend.2016.06.002] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 06/01/2016] [Accepted: 06/05/2016] [Indexed: 12/24/2022]
Abstract
Selection of the dominant follicle (DF) during a follicular wave is manifested by diameter deviation or continued growth rate of the largest follicle (F1) and decreased growth rate of the next largest follicle (F2) when F1 reaches about 8.5 mm in cattle. The process of deviation in the future DF begins about 12 h before diameter deviation and involves an F1 increase in granulosa LH receptors and estradiol and maintenance of intrafollicular free insulin-like growth factor 1 (IGF1). Thereby, only F1 is developmentally prepared to use the declining FSH in the wave-stimulating FSH surge and to respond to a transient increase in LH to become the DF. A follicle that emerges first may maintain an F1 ranking and become the DF by being first to reach a critical developmental stage. However, an early size advantage is not a requisite component of the deviation process as indicated by (1) F1 and F2 may switch diameter rankings during a common growth phase that precedes diameter deviation owing to intraovarian factors that affect growth of individual follicles; (2) any follicle that reaches 5 mm regardless of diameter ranking may become a DF unless it is selected against during deviation; (3) a subordinate follicle may become dominant if the DF is ablated; (4) when F1 is ablated at 8.5 mm, the next largest follicle that is greater than 7.0 mm or the first follicle to subsequently reach 7.0 mm becomes the DF; (5) after ablation of F1 at 8.5 mm, IGF1 and estradiol increase in the intrafollicular fluid of F2 beginning at 6 h, and F2 grows to 8.5 mm in 12 h to become the DF. These considerations indicate that selection of a DF or partitioning into a DF and subordinate follicles is not initiated before the end of the common growth phase. That is, the deviation process represents the entire follicle selection mechanism.
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Affiliation(s)
- O J Ginther
- Eutheria Foundation, Cross Plains, Wisconsin 53528, USA; Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
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Ginther O, Hoffman M. Interactions of side (left and right ovary) with the number of follicles per ovary and with the intraovarian relationships between dominant follicle and corpus luteum in heifers. Theriogenology 2016; 86:907-913. [DOI: 10.1016/j.theriogenology.2016.03.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 03/07/2016] [Accepted: 03/08/2016] [Indexed: 10/22/2022]
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Ginther OJ, Baldrighi JM, Siddiqui MAR, Wolf CA. Characteristics and functions of a minor FSH surge near the end of an interovulatory interval in Bos taurus heifers. Domest Anim Endocrinol 2016; 56:63-9. [PMID: 27131335 DOI: 10.1016/j.domaniend.2016.03.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Revised: 03/07/2016] [Accepted: 03/09/2016] [Indexed: 11/24/2022]
Abstract
The apparent function of a minor FSH surge based on temporality with follicular events was studied in 10 heifers with 2 follicular waves per interovulatory interval. Individual follicles were tracked from their emergence at 2 mm until their outcome was known, and a blood sample was collected for FSH and LH assay every 12 h from day -14 (day 0 = ovulation) to day 4. A minor FSH surge occurred in each heifer (peak, day -4.6 ± 0.2). Concentration of LH increased (P < 0.05) during the FSH increase of the minor surge but did not decrease during the FSH decrease. A minor follicular wave with 8.2 ± 2.0 follicles occurred in 6 of 10 heifers. The maximal diameter (mean, 3.4 ± 0.9 mm) of 77% of the minor-wave follicles occurred in synchrony on day -4.4 ± 0.4. Most (59%) of minor-wave follicles regressed before ovulation and 41% decreased and then increased in diameter (recovered) on day -1.9 ± 0.3 to become part of the subsequent wave 1. A mean of 3.7 ± 0.9 regressing subordinate follicles from wave 2 recovered on the day before or at the peak of the minor FSH surge. The growth rate of the preovulatory follicle decreased (P < 0.02) for 3 d before the peak of the minor FSH surge and then increased (P < 0.03). Concentration of LH increased slightly but significantly temporally with the resurgence in growth rate of the preovulatory follicle. A minor LH surge peaked (P < 0.0002) on day 3 at the expected deviation in growth rates between the future dominant and subordinate follicles. Results indicated on a temporal basis that the recovery of some regressing subordinate follicles of wave 2 was attributable to the minor FSH surge. The hypothesis was supported that some regressing follicles from the minor follicular wave recover to become part of wave 1.
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Affiliation(s)
- O J Ginther
- Eutheria Foundation, Cross Plains, WI 53528, USA; Pathobiological Sciences Department, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA.
| | | | - M A R Siddiqui
- Eutheria Foundation, Cross Plains, WI 53528, USA; Pathobiological Sciences Department, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - C A Wolf
- Pathobiological Sciences Department, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA; CAPES Foundation, Ministry of Education of Brazil, Brasilia, DF 70040-020
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Ginther O, Siddiqui M, Baldrighi J. Functional angiocoupling between follicles and adjacent corpus luteum in heifers. Theriogenology 2016; 86:465-71. [DOI: 10.1016/j.theriogenology.2016.03.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 03/02/2016] [Indexed: 11/27/2022]
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Ginther OJ, Siddiqui MAR, Baldrighi JM, Wolf CA. Systemic effect of follicle-stimulating hormone and intraovarian effect of the corpus luteum on complete regression vs recovery of regressing wave-2 follicles in heifers. Domest Anim Endocrinol 2016; 55:51-9. [PMID: 26773368 DOI: 10.1016/j.domaniend.2015.11.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 10/26/2015] [Accepted: 11/08/2015] [Indexed: 10/22/2022]
Abstract
Each subordinate of the second follicular wave (wave 2) was monitored, and the outcome was classified as fully regressed (decreased in diameter to 2 mm) or recovered (decreased initially and then increased to become a growing follicle of the subsequent wave 1). The changing diameter of each follicle after emergence at 2 mm and plasma concentration of follicle-stimulating hormone were determined every 12 h from the day of ovulation (Day 0) to 4 d after the subsequent ovulation in heifers with 2 follicular waves per interovulatory interval (n = 10). The number and percentage of wave-2 subordinates that initially regressed and then recovered (7.2 ± 1.0 follicles; 33.2 ± 5.1%) were less (P < 0.0008) than the number and percentage that completely regressed (15.0 ± 1.7; 66.8 ± 5.1%). Follicles that later recovered initially reached maximal diameter on a later day (P < 0.0001) after emergence at 2 mm (4.3 ± 0.2 d) and at a larger (P < 0.0001) diameter (5.8 ± 0.2 mm) than follicles that completely regressed (3.2 ± 0.1 d; 4.7 ± 0.1 mm). The follicle-stimulating hormone surge that stimulated wave 2 began earlier and was more sustained in a subgroup with a high percentage of recovered follicles (61%) than in a subgroup with a low percentage (24%). Recovery began on Day -1.0 ± 0.1 when the follicles had regressed to 3.7 ± 0.1 mm. Diameter of subordinate follicles on Day -6 or before the expected days of luteolysis was greater (P < 0.05) when in the corpus luteum (CL) ovary than when in the non-CL ovary. During expected luteolysis, more follicles (P < 0.008) per ovary continued to regress when ipsilateral to the CL (9.2 ± 1.1 follicles) than when contralateral (5.8 ± 1.1), and more follicles (P < 0.02) recovered from regression when contralateral to the CL (5.0 ± 0.8) than when ipsilateral (2.2 ± 0.6). The hypothesis that the CL has a local effect on the development, regression, and recovery of the subordinate follicles of wave 2 was supported.
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Affiliation(s)
- O J Ginther
- Eutheria Foundation, Cross Plains, WI, 53528, USA; Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, 1656 Linden Dr, Madison, WI, 53706, USA.
| | - M A R Siddiqui
- Eutheria Foundation, Cross Plains, WI, 53528, USA; Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, 1656 Linden Dr, Madison, WI, 53706, USA
| | - J M Baldrighi
- Eutheria Foundation, Cross Plains, WI, 53528, USA; Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, 1656 Linden Dr, Madison, WI, 53706, USA
| | - C A Wolf
- Eutheria Foundation, Cross Plains, WI, 53528, USA; Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, 1656 Linden Dr, Madison, WI, 53706, USA
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Mechanism for greater frequency of contralateral than ipsilateral relationships between corpus luteum and ovulatory follicle for wave 3 in heifers. Theriogenology 2016; 85:361-7. [DOI: 10.1016/j.theriogenology.2015.08.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 08/26/2015] [Accepted: 08/27/2015] [Indexed: 11/23/2022]
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Siddiqui M, Baldrighi J, Greene J, Wolf C, Ginther O. Spontaneous and experimental conversion of a regressing subordinate follicle of wave 1 to the dominant follicle of wave 2 in heifers. Theriogenology 2015; 83:1352-9. [DOI: 10.1016/j.theriogenology.2015.01.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 01/23/2015] [Accepted: 01/23/2015] [Indexed: 11/29/2022]
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