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Martínez-Boví R, Sala-Ayala L, Querol-Paajanen A, Plaza-Dávila M, Cuervo-Arango J. Effects of repeated embryo flushing without PGF 2α administration on luteal function, percentage of unwanted pregnancy and subsequent fertility in mares. Equine Vet J 2024. [PMID: 38403412 DOI: 10.1111/evj.14073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 01/30/2024] [Indexed: 02/27/2024]
Abstract
BACKGROUND PGF2α is commonly given at the end of embryo flushing (EF) to shorten the interval to the next oestrus and ovulation. OBJECTIVES To determine the effect of repeated EF on plasma progesterone concentration, percentage of mares with endometritis, unwanted pregnancy and subsequent fertility in mares flushed without the use of PGF2α . STUDY DESIGN Controlled experiments. METHODS Nine mares were inseminated in seven consecutive cycles (n = 63), to either perform an EF (n = 54) 7-9 days after ovulation or left pregnant (n = 9). PGF2α was not used to induce oestrus. Ultrasound examination and blood sampling were performed just before the EF and 72 h later to determine changes in progesterone concentration and signs of endometritis. RESULTS The overall percentage of positive EF/pregnancy was 55.5% (30/54) and 66.7% (6/9), respectively. The likelihood of pregnancy/positive EF in the first three cycles was 55.5% (15/29). This was not different (p > 0.1) from the fertility of the last four cycles (69.4%, 25/36). In five EF cycles (9.3%), mares had signs of endometritis and early luteolysis (progesterone <2 ng/mL) 72 h after EF. The reduction in progesterone concentration by 72 h after EF was greater (p < 0.05) for Day 9 (-2.3 ± 0.7 ng/mL) than Day 7 (-1.0 ± 0.8 ng/mL) or Day 8 (-1.3 ± 1.1 ng/mL) cycles. The progesterone concentration in non-flushed mares did not vary significantly during the sampled period (Day 7-12). There were 5 cycles in which the donor mare remained pregnant after the EF, although four were from a single mare. MAIN LIMITATIONS The mare population was limited to barren and maiden mares. The cycle order and operator allocation to each EF were not randomised. CONCLUSIONS EF induces a subtle, but significant reduction in progesterone concentrations compared with non-EF cycles. However, the percentage of mares with EF-induced full luteolysis is low (9.3%). The fertility of mares after repeated EF without administration of PGF2α was unaffected; however, there is a considerable risk of unwanted pregnancy (5/27 = 18.5%) in donors from which an embryo was not recovered.
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Affiliation(s)
- Rebeca Martínez-Boví
- Equine Fertility Group, Faculty of Veterinary Medicine, Universidad CEU Cardenal Herrera, CEU Universities, Alfara del Patriarca, Valencia, Spain
| | - Laura Sala-Ayala
- Equine Fertility Group, Faculty of Veterinary Medicine, Universidad CEU Cardenal Herrera, CEU Universities, Alfara del Patriarca, Valencia, Spain
| | - Aurora Querol-Paajanen
- Equine Fertility Group, Faculty of Veterinary Medicine, Universidad CEU Cardenal Herrera, CEU Universities, Alfara del Patriarca, Valencia, Spain
| | - María Plaza-Dávila
- Equine Fertility Group, Faculty of Veterinary Medicine, Universidad CEU Cardenal Herrera, CEU Universities, Alfara del Patriarca, Valencia, Spain
| | - Juan Cuervo-Arango
- Equine Fertility Group, Faculty of Veterinary Medicine, Universidad CEU Cardenal Herrera, CEU Universities, Alfara del Patriarca, Valencia, Spain
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Yang F, Wu H, Wu S, Cui D, Zhou J, Li N, Ma J, Zeng S. Effect of cloprostenol on luteolysis and comparison of different estrus synchronization protocols in jennies. Anim Reprod Sci 2023; 253:107263. [PMID: 37235952 DOI: 10.1016/j.anireprosci.2023.107263] [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: 02/11/2023] [Revised: 05/18/2023] [Accepted: 05/21/2023] [Indexed: 05/28/2023]
Abstract
Estrus synchronization is necessary for intensive donkey farming. Studies on estrus synchronization in jennies are, however, scarce. We aimed to investigate the susceptibility of the donkey corpus luteum to cloprostenol and design a successful estrus synchronization protocol. Firstly, the effects of different cloprostenol doses and the timing effect of cloprostenol treatment on estrous cycle was investigated. The time from treatment to luteolysis, the ovulation interval, pre-ovulatory diameter, and ovulation rates were compared between groups. Secondly, to identify the best protocol, eight estrus synchronization protocols from three categories were examined. In the first category, jennies in groups A (n = 55) and B (n = 30) received a progesterone releasing intra-vaginal device (JVID®) and cloprostenol treatment. In the second category (group C to F), jennies were pretreated with deslorelin, and then treated with JVID and cloprostenol, including groups C (n = 50), D (n = 50), E (n = 70), and F (n = 65). In the third category, jennies were treated with deslorelin and cloprostenol, including groups G (n = 40) and H (n = 40). Comparisons were made among groups regarding the degree of synchronization, ovulation, and pregnancy rates. Treatment with 0.4 mg cloprostenol on the third day following ovulation minimized the length of the luteal phase and estrous cycle. Synchronization rate varied from 60.0% to 88.6% among groups and was highest in group E. Pregnancy rates did not differ among the eight protocols. In conclusion, cloprostenol effectively induced luteolysis in jennies and a treatment protocol combining deslorelin, cloprostenol, and JVID is efficient for estrus synchronization in donkeys.
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Affiliation(s)
- Feng Yang
- National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing, China; College of Animal Science and Technology, Henan Agricultural University, Zhengzhou, China
| | - Hao Wu
- National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Shuaishuai Wu
- National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Daiyong Cui
- College of Animal Science and Technology, Yangzhou University, Yangzhou, China
| | - Jingqian Zhou
- College of Animal Science and Technology, Yangzhou University, Yangzhou, China
| | - Nan Li
- National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Jinliang Ma
- College of Animal Science and Technology, Yangzhou University, Yangzhou, China
| | - Shenming Zeng
- National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing, China.
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Silva ESM, Newcombe JR, Cuervo-Arango J. The Effect of Treatment with Oestradiol Benzoate on Oestrus Expression and Endometrial Oedema in Anovulatory and Cyclic Mares. Animals (Basel) 2023; 13:ani13050938. [PMID: 36899795 PMCID: PMC10000200 DOI: 10.3390/ani13050938] [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: 02/06/2023] [Revised: 03/01/2023] [Accepted: 03/03/2023] [Indexed: 03/08/2023] Open
Abstract
Oestrogens treatment is often used to induce oestrus behaviour in anoestrous mares to aid in the collection of stallion semen and as recipient mares to receive embryos when combined with progesterone. However, there are no studies to describe the effect of dose and individual mare on the intensity and duration of the response, in both anoestrous and cyclic mares. In Experiment 1, 13 anoestrous mares were treated with one of five doses of oestradiol benzoate (OB) (1, 1.5, 2, 3 and 4 mg) per mare in five consecutive treatment periods (n = 65), to determine the response in terms of endometrial oedema and oestrous behaviour. Experiment 2 and 3 used 3 mg of OB in cyclic mares to confirm or deny the presence of an active corpus luteum (CL). There was a dose rate of OB and individual mare effect (p < 0.05) on the intensity and persistence of endometrial oedema and oestrous behaviour. A total of 2 mg OB was enough to induce endometrial oedema and oestrous behaviour within 48 h in most mares. Mares with an active CL did not show endometrial oedema following treatment of 3 mg OB.
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Affiliation(s)
- Elisa S. M. Silva
- Faculty of Veterinary Medicine, Federal University of Uberlandia, Uberlândia 38408-100, Brazil
| | - John R. Newcombe
- Warren House Farm, Equine Fertility Clinic, Brownhills WS8 6LU, UK
| | - Juan Cuervo-Arango
- Equine Fertility Group, Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities, 46115 Valencia, Spain
- Correspondence:
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Janini LCZ, Silva MIA, Rizzoto G, Fonseca‐Alves CE, de Camillo BL, Aristizábal VHV, Negreiros NF, Corona LFC, Hara E, Mendonça VH, Mendonça HV, Cipriano RS. The use of prostaglandin applied in Bai Hui Acupoint on mare reproductive efficiency. EQUINE VET EDUC 2023. [DOI: 10.1111/eve.13762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Affiliation(s)
- Ludimila Cardoso Zoccal Janini
- Department of Veterinary Surgery and Animal Reproduction, School of Veterinary Medicine and Animal Science São Paulo State University (UNESP) Botucatu Brazil
| | | | - Guilherme Rizzoto
- Department of Veterinary Surgery and Animal Reproduction, School of Veterinary Medicine and Animal Science São Paulo State University (UNESP) Botucatu Brazil
| | - Carlos Eduardo Fonseca‐Alves
- Department of Veterinary Surgery and Animal Reproduction, School of Veterinary Medicine and Animal Science São Paulo State University (UNESP) Botucatu Brazil
| | - Beatriz Lippe de Camillo
- Department of Veterinary Surgery and Animal Reproduction, School of Veterinary Medicine and Animal Science São Paulo State University (UNESP) Botucatu Brazil
| | - Viviana Helena Vallejo Aristizábal
- Department of Veterinary Surgery and Animal Reproduction, School of Veterinary Medicine and Animal Science São Paulo State University (UNESP) Botucatu Brazil
| | | | | | - Eduardo Hara
- Central Araçá Reprodução Animal, Rodovia Marechal Rondon Araçatuba Brazil
| | | | | | - Rafael Silva Cipriano
- Catholic Salesian Auxilium University Center (UniSALESIANO) Araçatuba São Paulo Brazil
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Newcombe JR, Wilsher S, Cuervo-Arango J. The post-ovulatory rise in progesterone is lower and the persistence of oestrous behaviour longer during the first compared with the second cycle of the breeding season in mares. Reprod Domest Anim 2023; 58:141-145. [PMID: 36177828 PMCID: PMC10091980 DOI: 10.1111/rda.14273] [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: 06/22/2022] [Accepted: 09/28/2022] [Indexed: 01/07/2023]
Abstract
Mares are seasonally polyoestrous breeders. Therefore, the first ovulation of the season, following winter anoestrus, is the only cycle in which mares ovulate without the presence of an old CL from the previous cycle. The objective of this study was to compare the length of oestrous behaviour, and plasma progesterone concentrations during the early post-ovulatory period between mares after the first and second ovulation of the breeding season. Overall, 38 mares and 167 oestrous periods were used in the study. From those, 11 mares were used during the first and subsequent oestrous period to measure and compare the post-ovulatory rise in progesterone concentration, whereas all the mares were used to compare the length of the post-ovulatory oestrous behaviour between the first and subsequent cycles of the breeding season. The persistence of the post-ovulatory oestrus was longer (p < .001) following the first ovulation of the year (median of 52 h) compared with the subsequent ovulations (median of 36 h for second and later ovulations groups; n = 38 mares). The progesterone concentration at any of the four 8 h-intervals analysed (28, 36, 76 and 84 h post-ovulation) was lower (p < .01) following the first versus the second ovulation of the year. By 36 h post-ovulation the progesterone concentration of mares at the second ovulation of the year had passed the threshold of 2 ng/ml (2.1 ± 0.33 ng/ml), whereas in the first cycle it was 1.2 ± 0.13 ng/ml. In conclusion, mares had lower progesterone concentrations in their peripheral circulation and longer persistence of oestrous behaviour following the first ovulation of the year compared with the second and subsequent ovulatory periods of the breeding season.
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Affiliation(s)
| | - Sandra Wilsher
- Sharjah Equine Hospital, Sharjah, United Arab Emirates.,The Paul Mellon Laboratory of Equine Reproduction, Newmarket, UK
| | - Juan Cuervo-Arango
- Departamento de Medicina y Cirugía Animal, Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities, Valencia, Spain
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Hormonal Management for the Induction of Luteolysis and Ovulation in Andalusian Jennies: Effect on Reproductive Performance, Embryo Quality and Recovery Rate. Animals (Basel) 2022; 12:ani12020143. [PMID: 35049767 PMCID: PMC8772578 DOI: 10.3390/ani12020143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 01/04/2022] [Accepted: 01/06/2022] [Indexed: 11/17/2022] Open
Abstract
Two prostanglandins (luprostiol, LUP, and dinoprost, DIN) and two ovulation-inducing agents (human Chorionic Gonadotropin, hCG, and deslorelin, DES) were evaluated for luteolysis and estrus induction, and for ovulation induction, respectively, in embryo donor jennies. Twenty-six fertile Andalusian jennies were used. In Experiment 1, jennies (n = 112 cycles) were randomly treated with either LUP or DIN after embryo flushing. In Experiment 2, donors (n = 84 cycles) were randomly treated with either hCG or DES to induce ovulation. No differences were found between prostaglandins for all variables studied (prostaglandin–ovulation interval (POI), interovulatory interval (IOI), embryo recovery rate (ERR), positive flushing rate (PFR) and embryo grade (EG)). The ovulation rate was similar for hCG and DES (60.9% vs. 78.7%). However, the interval to ovulation (ITO) was affected (62.61 ± 7.20 vs. 48.79 ± 2.69 h). None of the other variables studied (ERR, PFR and EG) were affected (p > 0.05), except for embryo quality (p = 0.009). In short, both prostaglandins evaluated are adequate to induce luteolysis and estrus. Both ovulation-inducing agents hastened ovulation, but DES seems to be more effective than hCG. Follicular diameter affected the interval from treatment to ovulation, and high uterine edema was related to low embryo quality.
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Efficacy and Side Effects of Low Single Doses of Cloprostenol Sodium or Dinoprost Tromethamine to Induce Luteolysis in Donkeys. J Equine Vet Sci 2021; 107:103774. [PMID: 34802629 DOI: 10.1016/j.jevs.2021.103774] [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: 07/19/2021] [Revised: 09/14/2021] [Accepted: 09/15/2021] [Indexed: 11/21/2022]
Abstract
Due to the limited literature available evaluating doses of Prostaglandin F2α in donkeys, doses for horses have been extrapolated and used as guidelines. This study aimed to assess the efficacy and side effects of four different cloprostenol sodium and dinoprost tromethamine doses to induce luteolysis in jennies. Sixty-three cycles of seven Jennies (nine cycles per jenny) were used in this study. Seven days after ovulation, jennies randomly received one of the treatments in a crossover design as follows: Control, no treatment was administered; C1, 250 µg of cloprostenol sodium (CS, Estrumate , Merck Animal Health, USA); C2, 125 µg of CS; C3, 65.5 µg of CS, C4, 37.5 µg of CS; DT1, 5 mg of dinoprost tromethamine (DT, Lutalyse, Zoetis, USA); DT2, 2.5 mg of DT; DT3, 1.25 mg of DT; DT4, 0.625 mg of DT. Jennies were monitored for 30 minutes following treatment, and adverse effects were recorded. The measurement of the corpus luteum (CL) and the length of the estrous cycle were recorded. All DT and CS treatment doses were effective (P < .0001) in reducing the estrous cycle length compared to jenny's Control cycle. The CL volume was decreased in all treated groups one day after treatment (P < .05). The adverse effects were reduced as the dose of both Prostaglandin F2α analogs were reduced. In conclusion, a single low dose of dinoprost tromethamine (0.625 mg) or cloprostenol sodium (37.5 µg) can induce luteolysis and shorten the estrous length in jennies producing fewer adverse effects.
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The Combination of hCG and GnRH Analog to Hasten Ovulation in Mares Does not Change Luteal Function and Pregnancy Outcome in Embryo Recipient Mares. J Equine Vet Sci 2021; 105:103691. [PMID: 34607691 DOI: 10.1016/j.jevs.2021.103691] [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: 04/01/2021] [Revised: 05/21/2021] [Accepted: 06/19/2021] [Indexed: 11/21/2022]
Abstract
Equine practitioners often prescribe the combined use of hCG and GnRH to hasten ovulation due to presumed synergistic effects. Therefore, this study aimed to test whether the combination of hCG and deslorelin acetate to hasten ovulation in mares would show any effect in inducing ovulation more efficiently than when either drug is used by itself, and to verify whether this association would affect progesterone concentrations; corpus luteum (CL) diameter and blood flow; and pregnancy outcome in recipient mares after embryo transfer (ET). Seventeen mares had the ovulation hastened (≥35 mm follicle) as follow: Control, 1 mL of 0.9% NaCl solution; GnRH, 1 mg of deslorelin acetate; hCG, 1,500 IU of hCG; hCG+GnRH, 1mg of deslorelin acetate and 1,500 IU of hCG. CL diameter and blood flow, and serum progesterone concentrations were assessed between the day of ovulation induction and sixteen days after ovulation. In addition, data of 194 ET were retrospectively analyzed. Pregnancy rates at five days after ET and pregnancy loss up to 60 days of recipient mares with natural ovulation (Control, n=37), or with ovulation hastened with hCG (n=25), or deslorelin acetate (n=46), or the combination of these hormones (n=86), as described above, were assessed. The control group had a higher progesterone concentration on the day of ovulation than the GnRH group (P < .05). However, there were no differences in CL diameter and blood flow at any time point, as well as in progesterone concentration over time (P > .05). Pregnancy rates and pregnancy loss didn't differ between recipient mares treated or not with hormones. In conclusion, the combination of hCG and deslorelin acetate to hasten ovulation was not able to change luteal development, progesterone concentration, or pregnancy outcome in recipient mares after ET.
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Solodova E. The use of cloprostenol to reduce the diestral phase of the sexual cycle of mares. BIO WEB OF CONFERENCES 2021. [DOI: 10.1051/bioconf/20213606009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The article presents the results of the analysis of the pregnancy rates of mares depending on the duration of the intervals from cloprostenol preparation injection to ovulation. It was found that with a decrease in the interval (≤7 days), the pregnancy rate decreases by 30% (p≤0.05). To determine the optimal time for cloprostenol use, an analysis of the intervals from injection to ovulation was performed, depending on the day of the sexual cycle and the largest follicle diameter. The average intervals before ovulation in the groups, depending on the day of injection (5, 6-7, 8-10, 11-15 days), have a duration from 8.5±0.4 to 11.1±0.5 days. However, it is difficult to predict the time of ovulation, since the duration of the interval from cloprostenol treatment to ovulation varies greatly, the difference in the extreme values in the groups can be from 8 to 13 days. More precisely, it is possible to predict the duration of the interval until the follicle reaches 35 mm with a known diameter of the largest follicle at the time of injection. In this way, in the group with the diameter of the largest follicle ≤22 mm, this interval is 7.13±0.17 days, from 23 to 26 mm - 4.59±0.16 days, from 27 to 30 mm - 2.91±0.13 days. The difference in the duration of the intervals before ovulation in these groups is more significant – from 5 to 11 days and depends on the individual duration of the mare estrus.
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Okada CTC, Kaps M, Perez Quesada J, Gautier C, Aurich J, Aurich C. Diestrous Ovulations in Pregnant Mares as a Response to Low Early Postovulatory Progestogen Concentration. Animals (Basel) 2020; 10:ani10122249. [PMID: 33266083 PMCID: PMC7761349 DOI: 10.3390/ani10122249] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 11/25/2020] [Accepted: 11/28/2020] [Indexed: 12/23/2022] Open
Abstract
Simple Summary During early pregnancy in mares, progestogen is synthesized by the primary corpus luteum, which is the only source of progestogen until endometrial cup and accessory corpus luteum formation, from day 36 of pregnancy onwards. In the present study, we investigated the hormonal profile (gonadotrophin and progestogen concentrations) of 11 mares after experimental reduction of primary corpus luteum function. Two pregnancies of each mare were assigned to the control and treatment groups, respectively, and were analyzed until day 34. Low plasma progestogen concentration caused by the treatment reduced the negative feedback on the hypothalamic-pituitary axis, stimulating gonadotropin release, and luteal tissue response. Progestogen concentration restoration soon after treatment suggests a rebound effect and the resurgence of luteal function. In addition, diestrous ovulation was observed between days 11 and 15 in five treatment pregnancies (5/11), but none of the controls (0/11). Although the total luteal area increased after diestrous ovulations, corpus luteum size was not correlated to progestogen secretion. Results suggest that diestrous ovulations during early pregnancy in mares may reflect low progestogen concentrations in the early postovulatory period. Abstract Spontaneous prolongation of the luteal phase has been described in horses, but the underlying causes are still unclear. The present study investigated details of gonadotrophin and progestogen secretion in pregnant mares (n = 11) with or without experimentally reduced early postovulatory luteal function. From days 0 to 3 after ovulation, they were treated with the prostaglandin F2α (PGF2α) analogue cloprostenol or left untreated. After conceptus collection on day 34, they were assigned to the opposite treatment. Mares were affiliated to the group primary corpus luteum (n = 6) or diestrous corpus luteum (n = 5) depending on diestrous corpus luteum (CL) detection in the PGF pregnancy. For statistical comparisons, a p-value < 0.05 was significant. There was an effect of treatment (p < 0.01), but not of group on progestogen concentration. The concentration of LH was higher in PGF-treated than in untreated pregnancies (p < 0.05), but did not differ between groups. The FSH concentration did not differ between groups nor treatments. The total luteal tissue area was greater in mares with a diestrous ovulation during the PGF treatment pregnancy. Low progestogen concentration in the early postovulatory phase diminish the negative feedback on the hypothalamic-pituitary axis in early pregnancy and, thus, stimulate a luteal tissue response. Detection of secondary CL at the time of pregnancy examination in mares may reflect that early post-ovulatory progestogen concentrations were low.
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Affiliation(s)
- Carolina T. C. Okada
- Platform Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria; (C.T.C.O.); (M.K.); (J.P.Q.); (C.G.)
| | - Martim Kaps
- Platform Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria; (C.T.C.O.); (M.K.); (J.P.Q.); (C.G.)
| | - Javier Perez Quesada
- Platform Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria; (C.T.C.O.); (M.K.); (J.P.Q.); (C.G.)
| | - Camille Gautier
- Platform Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria; (C.T.C.O.); (M.K.); (J.P.Q.); (C.G.)
| | - Jörg Aurich
- Section for Obstetrics, Gynaecology and Andrology, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria;
| | - Christine Aurich
- Platform Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria; (C.T.C.O.); (M.K.); (J.P.Q.); (C.G.)
- Correspondence:
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Abstract
The objectives of this study were twofold. Firstly, the present study was designed to examine susceptibility of the corpus luteum (CL) in early diestrus in jennies; and secondly, to investigate the effect of two commonly used hormonal agents in horses on the induction of ovulation in jennies. The oestrus cycles of eleven jennies were monitored by ultrasound every day. When the dominant follicle reached a diameter of 30 mm, the jennies were treated by intramuscular administration of gonadotropin-releasing hormone agonist lecirelin (GnRH, 50 µg pro toto) in the first oestrus cycle, and human chorionic gonadotropin (hCG, 1500 IU pro toto) intramuscularly in the second oestrus cycle. Prostaglandin F2α analogue cloprostenolum (PGF2α, 0.125 mg pro toto) was administered intramuscularly 2 days after the first ovulation and the interovulatory interval was monitored. This study showed that intramuscular administration of 50 µg of GnRH agonist lecirelin resulted in ovulation within 48 h in 73% of treated jennies. Intramuscular administration 1500 IU of hCG was found to be poorly effective to induce ovulation, with 36% of animals ovulating within 48 h. Intramuscular administration of PGF2α analogue cloprostenol 2 days after ovulation was unsuccessful in attempting to shorten the interovulatory interval in donkeys.
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Histrelin acetate-induced ovulation in Brazilian Northeastern jennies (Equus asinus) with different follicle diameters. Theriogenology 2019; 136:95-100. [PMID: 31254727 DOI: 10.1016/j.theriogenology.2019.06.037] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 06/12/2019] [Accepted: 06/19/2019] [Indexed: 12/17/2022]
Abstract
The aim of the present study was to evaluate the efficacy of a GnRH analog for induction of ovulation in Brazilian Northeastern jennies (Equus asinus) with different follicle diameters. Four consecutive estrus of 10 jennies were used in a crossover study; C (Control, n = 10) jennies were evaluated by transrectal palpation and ultrasonography until a spontaneous ovulation and the intervals between the predetermined follicular size (25-28 mm [C1], 29-32 mm [C2] and 33-36 mm [C3] follicle) and ovulation were registered. In treated cycle, jennies had the ovulation induced by 250 μg of Histrelin acetate (Strelin®, Botupharma, Botucatu, Brazil) when respective follicle diameters 25-28 mm (T1), 29-32 mm (T2) and 33-36 mm (T3) were diagnosed. Ovulation was monitored by transrectal palpation and ultrasonography. Different follicle diameters significantly affected (P < 0.05) the interval until ovulation between control and matched treated cycles. Interval between prostaglandin administration and ovulation diagnosis was lower in jennies from T2 group (145.2 ± 34.6 h) compared with the control cycle (220.0 ± 41.8 h) and also with other treated cycles (T1 - 209.8 ± 48.0 h; T3 - 183.3 ± 33.9 h). Histrelin acetate treatment also reduces the interval between detection of predetermined follicular size and ovulation (P < 0.05) in all treated cycles groups compared with matched control group. Higher percentage (P < 0.05) of jennies had success of ovulation induction (36-48 h after Histrelin acetate injection) in all treated cycles in contrast with the matched control group. In addition, in comparison among treated cycle groups, more (P < 0.05) jennies (100%) in T2 ovulated between 36 and 48 h after ovulation induction, compared with T1 and T3, which did not differ (P > 0.05) from each other. Edema scoring and ovulation were not associated events (r = 0.0219). In conclusion, jennies with 29-32 mm follicles satisfactory responded to ovulation induction with Histrelin acetate, which allowed the shortening of interovulatory interval in all groups evaluated.
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Effect of the administration of alfaprostol 3 or 6 days after ovulation in jennies: ultrasonographic characteristic of corpora lutea and serum progesterone concentration. Theriogenology 2018; 121:175-180. [DOI: 10.1016/j.theriogenology.2018.08.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 08/04/2018] [Accepted: 08/07/2018] [Indexed: 11/18/2022]
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Hemodynamics of the corpus luteum in mares during experimentally impaired luteogenesis and partial luteolysis. Theriogenology 2017; 107:78-84. [PMID: 29132038 DOI: 10.1016/j.theriogenology.2017.10.045] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 10/25/2017] [Accepted: 10/30/2017] [Indexed: 11/20/2022]
Abstract
The aim of the current project was to characterize the luteal vascularity and the plasma concentrations of progesterone (P4), prolactin (PRL) and 13,14-dihydro-15-keto-PGF2α (PGFM) in mares with luteal disturbances during early and mid-diestrus. In Experiment 1, twenty-one mares were treated with 2 mL of 0.9% NaCl, or 1 mg Dinoprost, or 10 mg Dinoprost on day two after ovulation (Control-D2, 1/10PGF-D2 and PGF-D2 groups, respectively; n = 7 mares/group). In Experiment 2, similar treatments were performed eight days post-ovulation using a different cohort of 21 mares (Control-D8, 1/10PGF-D8 and PGF-D8 groups, respectively; n = 7 mares/group). Blood samples were collected hourly and power-Doppler examinations of the corpus luteum (CL) were performed every 6 h from H0 (moment immediately before treatment) to H48. Data collection was also done once a day from D0 (day of ovulation) to D20. In Experiment 1, the PGF-D2 and 1/10PGF-D2 groups had lower increase of plasma concentration of P4 until H48 and reduced maximum P4 concentrations on D8-D11 than mares from the Control-D2 group. However, no differences among groups were detected for luteal vascularity during early and mid-diestrus. In Experiment 2, complete and partial luteolysis were detected in mares from the PGF-D8 and 1/10PGF-D8 groups, respectively. Luteal vascularity and plasma P4 concentrations differed among Control-D8, PGF-D8 and 1/10PGF-D8 groups on H48. Partially regressed CLs (1/10PGF-D8 group) generated more Doppler signals than completed regressed CLs (PGF-D8 group) between D10 and D13. In both experiments, a transient increase in PRL activity was observed in parallel to the PGFM pulse in mares receiving 1 or 10 mg Dinoprost. The use of prostaglandin on D2 at conventional or 1/10 of the dose impaired the luteal development in mares. Moreover, the low dose of prostaglandin lead to partial regression of mature CLs. The blood supply was reduced in partially regressed CLs, but not in CLs undergoing impaired luteogenesis.
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Garcia-Muñoz A, Valldecabres-Torres X, Newcombe JR, Cuervo-Arango J, Garcia-Rosello E. Effect of exogenous progesterone administration on luteal sensitivity to PGF during the early development of the corpus luteum in mares and cows. Reprod Domest Anim 2017; 52:1074-1080. [DOI: 10.1111/rda.13029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 06/14/2017] [Indexed: 11/28/2022]
Affiliation(s)
- A Garcia-Muñoz
- Departamento de Producción y Sanidad Animal; Facultad de Veterinaria (Grupo de Investigación Fisiopatología de la Reproducción); Universidad CEU Cardenal Herrera; Valencia Spain
| | | | - JR Newcombe
- Warren House Farm; Equine Fertility Clinic; Brownhills West Midlands UK
| | - J Cuervo-Arango
- Department of Equine Sciences; Faculty of Veterinary Medicine; Utrecht University; Utrecht The Netherlands
| | - E Garcia-Rosello
- Departamento de Medicina y Cirugía Animal; Facultad de Veterinaria (Grupo de Investigación Fisiopatología de la Reproducción); Universidad CEU Cardenal Herrera; Valencia Spain
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The period of the follicular phase during which the uterus of mares shows estrus-like echotexture influences the subsequent pregnancy rate. Theriogenology 2016; 86:1506-1515. [DOI: 10.1016/j.theriogenology.2016.05.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 05/02/2016] [Accepted: 05/12/2016] [Indexed: 11/21/2022]
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17
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Coffman EA, Pinto CR. A Review on the Use of Prostaglandin F2α for Controlling the Estrous Cycle in Mares. J Equine Vet Sci 2016. [DOI: 10.1016/j.jevs.2016.01.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Cuervo-Arango J, Aguilar J, Vettorazzi M, Martínez-Boví R. eCG concentrations, luteal structures, return to cyclicity, and postabortion fertility in embryo transfer recipient mares. Theriogenology 2015; 84:1003-13. [DOI: 10.1016/j.theriogenology.2015.05.038] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Revised: 05/28/2015] [Accepted: 05/31/2015] [Indexed: 11/16/2022]
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Cuervo-Arango J, Mateu-Sánchez S, Aguilar J, Nielsen J, Etcharren V, Vettorazzi M, Newcombe J. The effect of the interval from PGF treatment to ovulation on embryo recovery and pregnancy rate in the mare. Theriogenology 2015; 83:1272-8. [DOI: 10.1016/j.theriogenology.2015.01.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2014] [Revised: 01/08/2015] [Accepted: 01/09/2015] [Indexed: 10/24/2022]
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Miró J, Vilés K, Anglada O, Marín H, Jordana J, Crisci A. Color Doppler provides a reliable and rapid means of monitoring luteolysis in female donkeys. Theriogenology 2015; 83:485-90. [DOI: 10.1016/j.theriogenology.2014.10.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 10/06/2014] [Accepted: 10/06/2014] [Indexed: 11/26/2022]
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Coffman E, Pinto C, Snyder H, Leisinger C, Cole K, Whisnant C. Antiluteogenic effects of serial prostaglandin F2α administration in cycling mares. Theriogenology 2014; 82:1241-5. [DOI: 10.1016/j.theriogenology.2014.07.038] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2014] [Revised: 07/29/2014] [Accepted: 07/30/2014] [Indexed: 11/30/2022]
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22
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Newcombe J, Cuervo-Arango J. The effect of multiple PGF treatment during early dioestrus on luteolysis and pregnancy rate in the mare. J Equine Vet Sci 2014. [DOI: 10.1016/j.jevs.2013.10.113] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Wenzinger B, Bleul U. Effect of a prostaglandin F2α analogue on the cyclic corpus luteum during its refractory period in cows. BMC Vet Res 2012; 8:220. [PMID: 23151276 PMCID: PMC3538667 DOI: 10.1186/1746-6148-8-220] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 11/05/2012] [Indexed: 12/19/2022] Open
Abstract
Background The goal of this study was to examine the response of the cyclic corpus luteum of cows to the administration of a prostaglandin F2α analogue (PGF) during the transition of refractoriness to responsiveness by investigating ultrasonographic changes in the corpus luteum and changes in plasma progesterone concentration in cows following the administration of PGF 3 and 5 days after ovulation. Results All cows that responded to PGF given on day 5 ovulated on day 9. In the cows that did not respond on day 5, the luteal cross-sectional area stagnated after treatment, whereas the plasma progesterone concentration continued to increase. In the cows that received PGF on day 3 of the oestrous cycle, the luteal cross-sectional area and the plasma progesterone concentration continued to increase. Conclusions The results of this study suggest that the transition of the bovine corpus luteum from refractoriness to responsiveness to PGF occurs during day 5 of the oestrous cycle because in 5 of 8 cows given PGF on day 5, early luteal regression was evident during the examination 24 hours after PGF administration.
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Affiliation(s)
- Beatrice Wenzinger
- Clinic for Reproductive Medicine, Vetsuisse-Faculty University of Zurich, Zurich, Switzerland.
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Bianchi CP, Cavilla MV, Jorgensen E, Benavente MA, Aba MA. Development of corpus luteum susceptibility to an analog of prostaglandin F2α, throughout the luteal phase in llamas (Lama glama). Anim Reprod Sci 2012; 131:199-203. [PMID: 22516230 DOI: 10.1016/j.anireprosci.2012.03.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Revised: 03/02/2012] [Accepted: 03/08/2012] [Indexed: 11/29/2022]
Abstract
The aim of the present study was to evaluate the susceptibility of the corpus luteum to d-cloprostenol (synthetic analog of PGF(2α)) throughout the luteal phase in llamas. Female llamas (n=43) were induced to ovulate by GnRH injection in the presence of an ovulatory follicle and randomly assigned into one of six groups: control and treated with an injection of d-cloprostenol on Day 3, 4, 5, 6 or 8 post GnRH. Blood samples were collected to determine plasma progesterone concentrations. There was no effect of treatment on animals injected on Day 3 or 4 post-GnRH. In animals treated on Day 5, different responses were observed. No effect of treatment was recorded in 27% of the animals whereas 55% of the llamas showed a transitory decrease followed by a recovery in plasma progesterone concentrations after d-cloprostenol injection, indicative of a resurgence of the corpus luteum, extending the luteal phase a day more than in control animals. In the remaining 18% of the animals injected on Day 5, (corresponding to those exhibiting the greatest plasma progesterone concentrations at the day of injection), complete luteolysis was observed. Plasma progesterone concentrations decreased to below 1 ng ml(-1) 24 h after d-cloprostenol in llamas injected on Day 6 or 8 post-GnRH. In conclusion, the corpus luteum of llamas is completely refractory to PGF(2α) until Day 4 after induction of ovulation, being partially sensitive by Day 5 and fully responsive to PGF(2α), by Day 6 after induction of ovulation.
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Affiliation(s)
- C P Bianchi
- Área de Endocrinología, Facultad de Ciencias Veterinarias, U.N.C.P.B.A., Campus Universitario, Paraje Arroyo Seco, Buenos Aires, Argentina.
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The effect of a single high dose of PGF2α administered to dairy cattle 3.5 days after ovulation on luteal function, morphology, and follicular dynamics. Theriogenology 2011; 76:1736-43. [DOI: 10.1016/j.theriogenology.2011.07.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2010] [Revised: 05/25/2011] [Accepted: 07/04/2011] [Indexed: 11/23/2022]
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Cuervo-Arango J, Newcombe JR. Relationship Between Dose of Cloprostenol and Age of Corpus Luteum on the Luteolytic Response of Early Dioestrous Mares: A Field Study. Reprod Domest Anim 2011; 47:660-5. [DOI: 10.1111/j.1439-0531.2011.01940.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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27
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Mozzaquatro FD, Verstegen JP, Douglas RH, Troedsson MHT, DeLaCorte FD, Silva CAM, Rubin MIB. Progesterone Production in Mares and Echographic Evaluation of the Corpora lutea Formed after Follicular Aspiration. Reprod Domest Anim 2011; 47:288-92. [DOI: 10.1111/j.1439-0531.2011.01856.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Evaluation of two oestrus synchronization regimens in eFSH-treated donor mares. Vet J 2010; 188:105-9. [PMID: 20392656 DOI: 10.1016/j.tvjl.2010.03.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2009] [Revised: 03/10/2010] [Accepted: 03/13/2010] [Indexed: 11/23/2022]
Abstract
Reliable methods for regulating oestrus and superovulation in equine embryo transfer (ET) programs are desirable. The objective in this study was to compare two oestrus synchronization methods combined with equine follicle-stimulating hormone (eFSH) treatment in an ET program. In the progesterone and estradiol-17β (P&E) group, mares (n=12) were given progesterone and estradiol-17β, daily for 10 days, followed by prostaglandin (PG)F(2α) on the last day. In the PG group, mares (n=12) were given PGF(2α) 5 days post-ovulation. In both groups donor mares were allocated to eFSH therapy, and were subsequently bred. Embryo recovery and transfer were performed routinely. The interval to ovulation (mean ± SEM, range) was not statistically different between donor mares in the P&E group (10.2±0.3, 9-12 days) and donor mares in the PG group (8.7±0.7, 4-12 days). Among donor mares, the synchrony of ovulations was higher following the P&E regimen (P<0.05); however, there was a tendency (P<0.06) for fewer ovulations than in the PG group (1.5±0.3 vs. 2.5±0.4 ovulations, respectively). Embryo recovery (0.9±0.3 vs. 1.4±0.3 embryo/recovery) and recipient pregnancy rate per transferred embryo (4/9, 44% vs. 4/15, 27%) were similar. It was concluded that the P&E regimen was more reliable for synchronization of oestrus in eFSH-treated mares but the fewer ovulations may curtail any advantage of this regimen.
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Metcalf ES, Thompson MM. The Effect of PGF2α-Induction of Estrus on Pregnancy Rates in Mares. J Equine Vet Sci 2010. [DOI: 10.1016/j.jevs.2010.02.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Hirano Y, Kimura J, Nambo Y, Yokota H, Nakamura S, Takemoto S, Himeno R, Mishima T, Matsui M, Miyake YI. Population of follicles and luteal structures during the oestrous cycle of mares detected by three-dimensional internal structure microscopy. Anat Histol Embryol 2009; 38:214-8. [PMID: 19469767 DOI: 10.1111/j.1439-0264.2008.00924.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The structure of the equine ovary is different from that of other mammals in its extremely large size, the presence of ovarian fossa and the inverted location of its cortex and medulla. A three-dimensional internal structure microscopy (3D-ISM), which consists of a computer-controlled slicer, a CCD camera, a laser disc recorder and a PC, is very useful for the observation of the internal structures in equine ovaries. In addition, the three-dimensional images of follicles and corpus luteum (CL) reconstructed by the segmentation technique can clarify the spatial arrangement in the equine ovary. In this study, to understand the changes in the ovarian internal structures of the mare during the oestrous cycle, the size and numbers of follicles and luteal structures were analysed by 3D-ISM in addition to the concentrations of progesterone (P(4)) and oestradiol-17beta. As a result, many small follicles (<10 mm in diameter) were detected. It was recognized that the luteal structures were distinguished into three types, such as the corpus haemorragicum (CH), which is formed by blood elements at the cavity after ovulation, CL and corpus albican (CA). There were some CHs and CL in the group, which had the concentration of P(4) > 1 ng/ml. CHs were also observed in the group, which had low level of P(4) (P(4) < 1 ng/ml). CAs were found regardless of the P(4) level. In conclusion, 3D-ISM enabled the internal observation of the ovarian structures in detail, and estimation of the stage of the ovarian cycle with complementary physiological information. The findings by 3D-ISM provide basic information for clinical applications.
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Affiliation(s)
- Y Hirano
- Department of Clinical Veterinary Science, The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
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Carluccio A, Panzani S, Contri A, Tosi U, De Amicis I, Veronesi M. Luteal function in jennies following PGF2α treatment 3 days after ovulation. Theriogenology 2008; 70:121-5. [DOI: 10.1016/j.theriogenology.2008.03.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2007] [Revised: 03/03/2008] [Accepted: 03/14/2008] [Indexed: 10/22/2022]
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