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Melchert M, Aurich J, Ertl R, Reichart U, Walter I, Gautier C, Kaps M, Aurich C. Involvement of somatotrophic hormones in the postpartum regulation of ovarian activity in mares. Domest Anim Endocrinol 2024; 88:106852. [PMID: 38701638 DOI: 10.1016/j.domaniend.2024.106852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 04/23/2024] [Accepted: 04/25/2024] [Indexed: 05/05/2024]
Abstract
Mares resume ovarian activity rapidly after foaling. Besides follicle-stimulating hormone (FSH) and luteinizing hormone (LH), the pituitary synthesizes prolactin and growth hormone which stimulate insulin-like growth factor (IGF) synthesis in the liver. We tested the hypothesis that follicular growth is initiated already antepartum, mares with early and delayed ovulation differ in IGF-1 release and that there is an additional IGF-1 synthesis in the placenta. Plasma concentrations of LH, FSH, IGF-1, IGF-2, activin and prolactin. IGF-1, IGF-2, prolactin and their receptors in placental tissues were analyzed at the mRNA and protein level. Follicular growth was determined from 15 days before to 15 days after foaling in 14 pregnancies. Mares ovulating within 15 days postpartum formed group OV (n=5) and mares not ovulating within 15 days group NOV (n=9). Before foaling, follicles with a diameter >1 cm were present in all mares and their number increased over time (p<0.05). Follicle growth after foaling was more pronounced in OV mares (day p<0.001, group p<0.05, day x group p<0.05) in parallel to an increase in LH concentration (p<0.001, day x group p<0.001) while FSH increased (p<0.001) similarly in both groups. Plasma concentrations of IGF-1 and prolactin peaked one day after foaling (p<0.001). The IGF-1 mRNA abundance was higher in the allantochorion but lower in the amnion of OV versus NOV mares (group p=0.01, localization x group p<0.01). The IGF-1 receptor mRNA was most abundant in the allantochorion (p<0.001) and IGF-1 protein was expressed in placental tissue without differences between groups. In conclusion, follicular growth in mares is initiated before foaling and placental IGF-1 may enhance resumption of ovulatory cycles.
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Affiliation(s)
- Maria Melchert
- Center for Animal Reproduction, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria.
| | - Jörg Aurich
- Center for Animal Reproduction, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria
| | - Reinhard Ertl
- Vetcore Facility for Research, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria
| | - Ursula Reichart
- Vetcore Facility for Research, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria
| | - Ingrid Walter
- Vetcore Facility for Research, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria; Institute of Pathology, Department of Pathobiology, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria
| | - Camille Gautier
- Center for Animal Reproduction, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria
| | - Martim Kaps
- Center for Animal Reproduction, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria
| | - Christine Aurich
- Center for Animal Reproduction, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria
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Gautier C, Aurich J, Melchert M, Wagner LH, Kaps M, Okada CTC, Ertl R, Walter I, Aurich C. Endocrine changes induced by GnRH immunisation and subsequent early re-stimulation of testicular function with a GnRH agonist in stallions. Reprod Fertil Dev 2024; 36:RD23185. [PMID: 38237640 DOI: 10.1071/rd23185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 12/23/2023] [Indexed: 04/11/2024] Open
Abstract
CONTEXT Resumption of testicular function after gonadotrophin-releasing hormone (GnRH) immunisation varies among individual animals and some stallions regain fertility only after a prolonged time. AIMS This study evaluated endocrine effects of GnRH immunisation and early subsequent re-stimulation with a GnRH agonist. We hypothesised that GnRH agonist treatment advances resumption of normal endocrine function in GnRH-vaccinated stallions. METHODS Shetland stallions were assigned to an experimental and a control group (n =6 each). Experimental stallions were GnRH-immunised twice, 4weeks apart. Each experimental stallion was hemicastrated together with an age-matched control animal when testosterone concentration decreased below 0.3ng/mL. Three weeks later, daily treatment with the GnRH agonist buserelin was initiated (4μg/day for 4weeks followed by 8μg/day). The remaining testicle was removed when testosterone concentration exceeded 0.5ng/mL in vaccinated stallions. Blood was collected for LH, FSH, oestradiol and anti-müllerian hormone (AMH) analyses, and testicular and epididymal tissue were conserved for real-time qPCR and histology. KEY RESULTS GnRH vaccination reduced blood concentrations of LH and FSH, with a structural deterioration of testicular tissue and disruption of spermatogenesis. Daily buserelin treatment for approximately 60days partially restored gonadotropin secretion and induced a recovery of the functional organisation of the testicular tissue with effective spermatogenesis. CONCLUSIONS Endocrine testicular function can be restored in GnRH-vaccinated stallions by daily low-dose buserelin treatment. The buserelin treatment protocol may potentially be improved regarding the dose, interval and duration. IMPLICATIONS Daily buserelin treatment can be recommended for treatment of GnRH-vaccinated stallions with prolonged inhibition of testicular function.
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Affiliation(s)
- Camille Gautier
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, Vienna 1210, Austria
| | - Jörg Aurich
- Obstetrics, Gynecology and Andrology, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, Vienna 1210, Austria
| | - Maria Melchert
- Obstetrics, Gynecology and Andrology, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, Vienna 1210, Austria
| | - Lisa-Hélène Wagner
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, Vienna 1210, Austria
| | - Martim Kaps
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, Vienna 1210, Austria
| | - Carolina T C Okada
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, Vienna 1210, Austria
| | - Reinhard Ertl
- VetCore Facility for Research, Vetmeduni Vienna, Veterinärplatz 1, Vienna 1210, Austria
| | - Ingrid Walter
- VetCore Facility for Research, Vetmeduni Vienna, Veterinärplatz 1, Vienna 1210, Austria; and Institute of Morphology, Department of Pathobiology, Vetmeduni Vienna, Veterinärplatz 1, Vienna 1210, Austria
| | - Christine Aurich
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, Vienna 1210, Austria
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Wagner LH, Aurich J, Melchert M, Okada CTC, Gautier C, Kaps M, Claaßen S, Aurich C. Low progesterone concentration in early pregnancy is detrimental to conceptus development and pregnancy outcome in horses. Anim Reprod Sci 2023; 257:107334. [PMID: 37725863 DOI: 10.1016/j.anireprosci.2023.107334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Revised: 08/09/2023] [Accepted: 09/15/2023] [Indexed: 09/21/2023]
Abstract
High progesterone concentrations in the early luteal phase support pregnancy, whereas subphysiological progesterone concentrations delay embryonic development at least until placentation. In this study, fetal growth and development of pregnancy was investigated in pregnancies with prostaglandin F2α-induced low progesterone concentrations (PGF) in the early luteal phase and control pregnancies (CON) in the same mares (n = 12). Mares were inseminated and in PGF pregnancies received the prostaglandin F2α analogue cloprostenol (62.5 µg) on days 0-3 after ovulation to induce subphysiological progesterone concentrations; CON pregnancies remained untreated. Mares were assigned to PGF or CON treatments in alternating order and received the opposite treatment in the following year. Blood was collected and conceptus size determined repeatedly by transrectal (≤day 101) and transabdominal (>day 101) ultrasonography. After birth, foals were weighed, measured and submitted to a clinical examination. Treatment PGF resulted in fewer pregnancies than CON treatment. All foals born from CON pregnancies were healthy and mature, whereas 4/7 PGF pregnancies were either lost (one embryonic death, one abortion) or resulted in the birth of compromised foals (P = 0.018). Size of the conceptus (e.g., diameter day 49: PGF 6.6 ± 0.7, CON 7.7 ± 0.7 cm, P = 0.006) and embryo proper (e.g., crown rump length day 54; PGF 4.4 ± 0.8, CON 5.8 ± 0.6 cm, P = 0.015) differed between treatments. These size differences decreased over time and at birth PGF foals did not differ significantly from CON foals. In conclusion, reduced progesterone concentration in the early luteal phase leads to delayed conceptus growth beyond placentation and increased pregnancy loss.
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Affiliation(s)
- Lisa-Hélène Wagner
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Vienna 1210, Austria
| | - Jörg Aurich
- Obstetrics, Gynecology and Andrology, Department for Small Animals and Horses, Vetmeduni Vienna, Vienna 1210, Austria
| | - Maria Melchert
- Obstetrics, Gynecology and Andrology, Department for Small Animals and Horses, Vetmeduni Vienna, Vienna 1210, Austria
| | - Carolina T C Okada
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Vienna 1210, Austria
| | - Camille Gautier
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Vienna 1210, Austria
| | - Martim Kaps
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Vienna 1210, Austria
| | - Svenja Claaßen
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Vienna 1210, Austria
| | - Christine Aurich
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Vienna 1210, Austria.
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Gautier C, Aurich J, Kaps M, Okada CTC, Wagner LH, Melchert M, Aurich C. Re-stimulation of testicular function in GnRH-vaccinated stallions by daily GnRH agonist treatment. Theriogenology 2022; 194:27-34. [PMID: 36193591 DOI: 10.1016/j.theriogenology.2022.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 09/07/2022] [Accepted: 09/10/2022] [Indexed: 10/14/2022]
Abstract
In stallions temporarily not intended for breeding, reversible suppression of testicular function by vaccination against GnRH can be of interest. In the present study, effects of GnRH agonist treatment on the resumption of testicular function after GnRH vaccination were investigated. Testis size, testosterone release, semen characteristics and behavior were evaluated. We hypothesized that GnRH agonist treatment would restore testicular function. Shetland stallions were assigned to an experimental and a control group (n = 6 each). Experimental stallions were GnRH-immunized twice, four weeks apart. Ejaculates for semen analysis and blood for analysis of testosterone concentration and GnRH antibody titers were collected. Each experimental stallion was hemicastrated together with an age-matched control animal when testosterone concentration decreased below 0.3 ng/mL. Three weeks thereafter, daily treatment with the GnRH agonist buserelin was initiated (4 μg/day for 4 weeks followed by 8 μg/day). The remaining testicle was removed when testosterone concentration exceeded 0.5 ng/mL in vaccinated stallions. Time from exposure to a mare until mounting increased in GnRH-vaccinated stallions and decreased with buserelin treatment. Total sperm count decreased after vaccination but increased only slightly in response to buserelin. Sperm motility and percentage of membrane-intact spermatozoa decreased after vaccination and returned to pre-vaccination values with buserelin treatment. Testosterone concentration and testis volume decreased after GnRH vaccination and started to increase with buserelin treatment. In conclusion, the downregulation of testicular function by GnRH vaccination can be counteracted with buserelin. This approach may be useful in GnRH-vaccinated stallions with prolonged suppression of testicular function.
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Affiliation(s)
- Camille Gautier
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, 1210, Vienna, Austria.
| | - Jörg Aurich
- Obstetrics, Gynecology and Andrology, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, 1210, Vienna, Austria
| | - Martim Kaps
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, 1210, Vienna, Austria
| | - Carolina T C Okada
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, 1210, Vienna, Austria
| | - Lisa-Hélène Wagner
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, 1210, Vienna, Austria
| | - Maria Melchert
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, 1210, Vienna, Austria
| | - Christine Aurich
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, 1210, Vienna, Austria
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Dirks E, de Heus P, Joachim A, Cavalleri JMV, Schwendenwein I, Melchert M, Fuehrer HP. First Case of Autochthonous Equine Theileriosis in Austria. Pathogens 2021; 10:pathogens10030298. [PMID: 33806575 PMCID: PMC7998884 DOI: 10.3390/pathogens10030298] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 02/22/2021] [Accepted: 02/26/2021] [Indexed: 11/16/2022] Open
Abstract
A 23-year-old pregnant warmblood mare from Güssing, Eastern Austria, presented with apathy, anemia, fever, tachycardia and tachypnoea, and a severely elevated serum amyloid A concentration. The horse had a poor body condition and showed thoracic and pericardial effusions, and later dependent edema and icteric mucous membranes. Blood smear and molecular analyses revealed an infection with Theileria equi. Upon treatment with imidocarb diproprionate, the mare improved clinically, parasites were undetectable in blood smears, and 19 days after hospitalization the horse was discharged from hospital. However, 89 days after first hospitalization, the mare again presented to the hospital with an abortion, and the spleen of the aborted fetus was also PCR-positive for T. equi. On the pasture, where the horse had grazed, different developmental stages of Dermacentor reticulatus ticks were collected and subjected to PCR, and one engorged specimen was positive for T. equi. All three amplicon sequences were identical (T. equi genotype E). It is suspected that T. equi may repeatedly be transmitted in the area where the infected mare had grazed, and it could be shown that transmission to the fetus had occurred. Due to the chronic nature of equine theileriosis and the possible health implications of infection, it is advised to include this disease in the panel of differential diagnoses in horses with relevant clinical signs, including horses without travel disease, and to be aware of iatrogenic transmission from inapparent carrier animals.
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Affiliation(s)
- Esther Dirks
- Clinical Unit of Equine Internal Medicine, Department Hospital for Companion Animals and Horses, University of Veterinary Medicine Vienna, 1210 Vienna, Austria; (E.D.); (P.d.H.); (J.-M.V.C.)
| | - Phebe de Heus
- Clinical Unit of Equine Internal Medicine, Department Hospital for Companion Animals and Horses, University of Veterinary Medicine Vienna, 1210 Vienna, Austria; (E.D.); (P.d.H.); (J.-M.V.C.)
| | - Anja Joachim
- Department of Pathobiology, Institute of Parasitology, University of Veterinary Medicine Vienna, 1210 Vienna, Austria;
| | - Jessika-M. V. Cavalleri
- Clinical Unit of Equine Internal Medicine, Department Hospital for Companion Animals and Horses, University of Veterinary Medicine Vienna, 1210 Vienna, Austria; (E.D.); (P.d.H.); (J.-M.V.C.)
| | - Ilse Schwendenwein
- Clinical Pathology Platform, Department of Pathobiology, University of Veterinary Medicine Vienna, 1210 Vienna, Austria;
| | - Maria Melchert
- Centre for Insemination and Embryo transfer Platform, Department Hospital for Companion Animals and Horses, University of Veterinary Medicine Vienna, 1210 Vienna, Austria;
| | - Hans-Peter Fuehrer
- Department of Pathobiology, Institute of Parasitology, University of Veterinary Medicine Vienna, 1210 Vienna, Austria;
- Correspondence: ; Tel.: +43-125-077-2205
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Nagel C, Melchert M, Aurich C, Aurich J. Differences in Endocrine and Cardiac Changes in Mares and Her Fetus before, during, and after Parturition in Horses of Different Size. Animals (Basel) 2020; 10:ani10091577. [PMID: 32899617 PMCID: PMC7552300 DOI: 10.3390/ani10091577] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/27/2020] [Accepted: 09/02/2020] [Indexed: 12/19/2022] Open
Abstract
Simple Summary Monitoring of the pregnant mare and her fetus is based on hormone analysis and heart rate recordings which may differ among small, medium-size, and full-size horses. Therefore, Shetland (n = 6), Haflinger (n = 8), and Warmblood pregnancies (n = 9) were studied before and at foaling. Foal weight always approximated 10% of mare weight but relative placenta weight was highest in full-size mares. The concentrations of progestins (hormones that maintain pregnancy) and cortisol (a hormone involved in the onset of foaling but also in an animal’s response to stress) was highest in full-size mares. Progestin concentration decreased towards foaling while cortisol concentration increased. Heart rate of mares increased before foaling with the most pronounced increase in small mares. Overall, Shetland mares foaled earlier than larger-size mares. At foaling, atrio-ventricular blocks (physiological omission of heart beats) regularly occurred in full-size mares but only occasionally in medium-size and small mares, reflecting differences in heart efficiency. In conclusion, some differences exist before and at foaling in horses of different size. Abstract Equine fetomaternal monitoring is based on endocrine and cardiac parameters which may differ among small, medium-size, and full-size horses. Therefore, Shetland (n = 6), Haflinger (n = 8), and Warmblood pregnancies (n = 9) were studied during late gestation and at foaling. Weight of mares, foals and placenta, plasma progestin and cortisol concentration, heart rate and heart rate variability (HRV) were determined. Foal weight always approximated 10% of mare weight but relative placenta weight was highest in full-size mares (p < 0.05). Progestin (p < 0.001) and cortisol (p < 0.05) concentration was highest in full-size mares. Progestin concentration decreased towards parturition (p < 0.001) while cortisol concentration increased (p < 0.01). Maternal heart rate increased before foaling with the most pronounced increase in small mares (p < 0.001). The HRV increased during foaling and decreased when delivery was completed (p < 0.001). Changes were most pronounced in full-size mares (p < 0.001). Atrio-ventricular blocks regularly occurred in parturient full-size mares but only occasionally in medium-size and small mares (time p < 0.05, time × group p < 0.05). This may reflect breed differences in cardiovascular efficiency. Fetal heart rate decreased towards birth (p < 0.001) with the most pronounced decrease in full-size horses (p < 0.01). Fetal HRV showed no consistent changes before birth but increased when the foal was born (p < 0.001), this increase being most pronounced in full-size foals (p < 0.05). In conclusion, this study demonstrates both similarities and differences in peripartum endocrine and cardiac changes in horses of different size.
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Affiliation(s)
- Christina Nagel
- Graf Lehndorff Institute for Equine Science, Vetmeduni Vienna, 16845 Neustadt (Dosse), Germany;
| | - Maria Melchert
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, 1210 Vienna, Austria; (M.M.); (C.A.)
| | - Christine Aurich
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, 1210 Vienna, Austria; (M.M.); (C.A.)
| | - Jörg Aurich
- Obstetrics, Gynecology and Andrology, Department for Small Animals and Horses, Vetmeduni Vienna, 1210 Vienna, Austria
- Correspondence:
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Okada CTC, Kaps M, Scarlet D, Handschuh S, Gautier C, Melchert M, Aurich J, Aurich C. Low plasma progestin concentration during the early postovulatory phase impairs equine conceptus development in the late preimplantation phase. Reprod Fertil Dev 2020. [DOI: 10.1071/rd20116] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Melchert M, Aurich C, Aurich J, Gautier C, Nagel C. External stress increases sympathoadrenal activity and prolongs the expulsive phase of foaling in pony mares. Theriogenology 2019; 128:110-115. [PMID: 30743099 DOI: 10.1016/j.theriogenology.2019.02.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 01/21/2019] [Accepted: 02/03/2019] [Indexed: 11/28/2022]
Abstract
Mares usually give birth when they perceive their environment as safe and therefore disturbance at foaling may inhibit labor. In this study, foaling mares were transferred to an unfamiliar environment at rupture of the allantochorion (stress, n = 6) or were left undisturbed (control, n = 5). The progress of foaling, heart rate, heart rate variability (HRV) and plasma catecholamine, oxytocin and cortisol concentration were determined. In stressed mares, time from rupture of the allantochorion to appearance of the fetal feet (5.3 ± 1.1 vs. 1.6 ± 0.4 min) and total length of fetal expulsion were longer than in controls (both p < 0.05). Heart rate decreased during the expulsive phase of foaling in control mares (p < 0.01) but increased transiently in stressed mares. Heart rate calculated as percentage of the baseline was higher in stressed than in control mares (p = 0.05). HRV variables SDRR (standard deviation of the beat-to-beat interval) and RMSSD (root mean square of successive beat-to-beat differences) increased during foal expulsion (SDRR p < 0.01 and RMSSD p < 0.05). The increase in HRV was delayed in stressed compared to control mares (SDRR and RMSSD time x group p < 0.05). Plasma epinephrine and norepinephrine concentrations calculated as area under the curve for the expulsive phase of foaling were higher in stressed than control mares (p < 0.05). Concentrations of oxytocin and cortisol were elevated during foal expulsion (both p < 0.001) but not different between groups. In conclusion, disturbance of mares during expulsion of the foal prolonged foaling. This effect is most likely mediated via increased sympathetic activity and not inhibition of oxytocin release.
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Affiliation(s)
- Maria Melchert
- Gynecology, Obstetrics and Andrology, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria
| | - Christine Aurich
- Artificial Insemination and Embryo Transfer, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria
| | - Jörg Aurich
- Gynecology, Obstetrics and Andrology, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria
| | - Camille Gautier
- Gynecology, Obstetrics and Andrology, Department for Small Animals and Horses, Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria
| | - Christina Nagel
- Graf Lehndorff Institute, Vetmeduni Vienna, 16845 Neustadt (Dosse), Germany.
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Eisleben R, Melchert M. This convenience food system is designed around the oven. Mod Hosp 1973; 120:108-10. [PMID: 4786761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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