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Zhao F, Wei QW, Li BJ, Weng QN, Jiang Y, Ning CB, Liu KQ, Wu WJ, Liu HL. Impact of adrenocorticotropin hormone administration on the endocrinology, estrus onset, and ovarian function of weaned sows. Endocr J 2022; 69:23-33. [PMID: 34456194 DOI: 10.1507/endocrj.ej21-0184] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Chronic stress affects the reproductive health of mammals; however, the impact of adrenocorticotropin hormone (ACTH) level elevation during chronic stress on the reproduction of weaned sows remains unclear. In this study, nine weaned sows with the same parturition date were randomly divided into control group (n = 4) and ACTH group (n = 5). Each group received intravenous administration of ACTH three times daily for 7 days. Blood samples were collected every 3 h after injection. A radioimmunoassay was used to measure the concentrations of cortisol, luteinizing hormone (LH), follicle-stimulating hormone (FSH), progesterone (P4) and estradiol-17β (E2) in the blood. Estrus was determined according to changes in the vulva and the boar contact test. The mRNA expressions of glucocorticoid receptor, FSH receptor, LH receptor (LHR) in the corpus luteum (CL) were detected by qRT-PCR. The results showed that ACTH administration substantially delayed the initiation of estrus and the pre-ovulatory LH peak. The sows of control group ovulated within 10 days and the ovulation rate was 100%, while it was 60% in the ACTH group. Two sows of ACTH group showed pseudo-estrus. The E2 concentrations significantly decreased in the ACTH group at 36 h, 42 h and 66 h of the experimental period. The P4 concentrations in the ACTH group significantly decreased at 132, 138, and 147 h of the experimental period. ACTH significantly reduced the LHR mRNA expression in CLs. In conclusion, long-term repeated ACTH administration affects the endocrinology, estrus onset, and ovarian function of weaned sows.
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Affiliation(s)
- Fang Zhao
- Institute of Animal Science, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
- Key Laboratory of Crop and Animal Integrated Farming, Ministry of Agriculture and Rural Affairs, Nanjing, 210014, China
| | - Quan-Wei Wei
- Laboratory of Animal Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Bo-Jiang Li
- Laboratory of Animal Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Qian-Nan Weng
- Laboratory of Animal Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yi Jiang
- Laboratory of Animal Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Cai-Bo Ning
- Laboratory of Animal Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Kai-Qing Liu
- Laboratory of Animal Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Wang-Jun Wu
- Laboratory of Animal Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Hong-Lin Liu
- Laboratory of Animal Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
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2
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Jones NC, O'Brien TJ, Carmant L. Interaction between sex and early-life stress: influence on epileptogenesis and epilepsy comorbidities. Neurobiol Dis 2014; 72 Pt B:233-41. [PMID: 25266701 DOI: 10.1016/j.nbd.2014.09.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 09/08/2014] [Accepted: 09/12/2014] [Indexed: 12/22/2022] Open
Abstract
Epilepsy is a common brain disorder which is characterised by recurring seizures. In addition to suffering from the constant stress of living with this neurological condition, patients also frequently experience comorbid psychiatric and cognitive disorders which significantly impact their quality of life. There is growing appreciation that stress, in particular occurring in early life, can negatively impact brain development, creating an enduring vulnerability to develop epilepsy. This aligns with the solid connections between early life environments and the development of psychiatric conditions, promoting the possibility that adverse early life events could represent a common risk factor for the later development of both epilepsy and comorbid psychiatric disorders. The influence of sex has been little studied, but recent research points to potential important interactions, particularly with regard to effects mediated by HPA axis programming. Understanding these interactions, and the underlying molecular mechanisms, will provide important new insights into the causation of both epilepsy and of psychiatric disorders, and potentially open up novel avenues for treatment.
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Affiliation(s)
- Nigel C Jones
- Department of Medicine (Royal Melbourne Hospital), Melbourne Brain Centre, University of Melbourne, Parkville, VIC, Australia.
| | - Terence J O'Brien
- Department of Medicine (Royal Melbourne Hospital), Melbourne Brain Centre, University of Melbourne, Parkville, VIC, Australia
| | - Lionel Carmant
- Centre de Recherche du Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montréal, Québec, Canada
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3
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Mack LA, Lay DC, Eicher SD, Johnson AK, Richert BT, Pajor EA. Growth and reproductive development of male piglets are more vulnerable to midgestation maternal stress than that of female piglets12. J Anim Sci 2014; 92:530-48. [PMID: 24398844 DOI: 10.2527/jas.2013-6773] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- L. A. Mack
- Department of Animal Sciences, Purdue University, West Lafayette, IN 47907
| | - D. C. Lay
- USDA-Agricultural Research Service, Livestock Behavior Research Unit, West Lafayette, IN 47907
| | - S. D. Eicher
- Department of Animal Science, Iowa State University, Ames, IA 50011
| | - A. K. Johnson
- Department of Animal Science, Iowa State University, Ames, IA 50011
| | - B. T. Richert
- Department of Animal Sciences, Purdue University, West Lafayette, IN 47907
| | - E. A. Pajor
- Department of Production Animal Health, University of Calgary, Calgary, AB, CA T2N IN4
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4
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Lay DC, Kattesh HG, Cunnick JE, Daniels MJ, McMunn KA, Toscano MJ, Roberts MP. Prenatal stress effects on pig development and response to weaning1. J Anim Sci 2008; 86:1316-24. [DOI: 10.2527/jas.2007-0812] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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5
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BRÜSSOW KP, SCHNEIDER F, TUCHSCHERER A, EGERSZEGI I, RÁTKY J. Comparison of Luteinizing Hormone, Leptin and Progesterone Levels in the Systemic Circulation (Vena jugularis) and near the Ovarian Circulation (Vena cava caudalis) during the Oestrous Cycle in Mangalica and Landrace Gilts. J Reprod Dev 2008; 54:431-8. [DOI: 10.1262/jrd.20069] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
| | | | | | | | - Jozsef RÁTKY
- Research Institute for Animal Breeding and Nutrition
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6
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von Borell E, Dobson H, Prunier A. Stress, behaviour and reproductive performance in female cattle and pigs. Horm Behav 2007; 52:130-8. [PMID: 17467708 DOI: 10.1016/j.yhbeh.2007.03.014] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2007] [Revised: 03/27/2007] [Accepted: 03/27/2007] [Indexed: 11/18/2022]
Abstract
Female farm animals are exposed to a great variety of environmental and management related stressors. As a consequence, their reproductive and maternal abilities may be compromised through mechanisms acting on the hypothalamic, pituitary, ovarian and uterine function. Responses to short- and long-term stressors may differ as short-term stressors often fail to affect reproduction or even may have stimulatory effects. Thus, the stress response induces diverse neuroendocrine reactions that can either increase or decrease the probability of an animal reproducing depending on the specific situation. The aim of the present review is to summarise the current knowledge on the stress concept and its implications on behaviour and reproductive performance in cows and female pigs as phenomena reported in laboratory animals are unable to explain all effects encountered in domesticated farm animals.
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Affiliation(s)
- Eberhard von Borell
- Institute of Agricultural and Nutritional Sciences, Faculty of Natural Sciences III, Martin-Luther-University Halle-Wittenberg, 06108 Halle, Germany.
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7
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Goyarts T, Dänicke S, Brüssow KP, Valenta H, Ueberschär KH, Tiemann U. On the transfer of the Fusarium toxins deoxynivalenol (DON) and zearalenone (ZON) from sows to their fetuses during days 35–70 of gestation. Toxicol Lett 2007; 171:38-49. [PMID: 17544604 DOI: 10.1016/j.toxlet.2007.04.003] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2006] [Revised: 04/11/2007] [Accepted: 04/12/2007] [Indexed: 11/21/2022]
Abstract
Eleven pregnant sows with a body weight between 153 and 197 kg were fed a control diet (CON, 0.15 mg DON and 0.0035 mg ZON/kg diet) or a diet containing 15% of Fusarium toxin contaminated triticale (MYCO, 4.42 mg DON and 0.048 mg ZON/kg diet) in the period of day 35 and 70 of gestation. The indirect effect of feed intake was separated from the direct effects of the Fusarium toxins by the restricted feeding regimen where all sows were fed the same amount of feed (2000 g/d) over the whole study. At the end of experiment, fetuses were delivered by Caesarian section and samples of serum, bile, urine, liver, kidney and spleen of euthanatized sows and fetuses were taken to analyze the concentrations of DON, ZON and their metabolites. Feeding the Fusarium toxin contaminated diet to pregnant sows caused neither adverse effects on performance, organ weights and maintenance of pregnancy of sows nor on fetus weight and length. Furthermore, no teratogenic or embryolethal effects could be observed in the MYCO group. Hematological and clinical-chemical parameters of sows and fetuses were not affected by feeding, with the exception of significantly lower GLDH (glutamate dehydrogenase) serum activities in MYCO sows. The carry over of DON and ZON from the diet to the sow or fetus tissues was calculated by the diet ratio (sum of concentrations of all metabolites in the physiological specimen divided by the dietary toxin concentration), while the fetus ratio was evaluated by the sum of concentrations of all metabolites in the physiological specimen of the fetus divided by that of the sows. DON and deepoxy-DON were found in urine, bile, serum, liver, kidney and spleen of sows of the MYCO group, but not in the bile of fetuses (spleen not analyzed). ZON and its metabolite alpha-zearalenol (alpha-ZOL) were detected in urine and bile of sows, while all specimens of fetuses as well as serum and liver of sows were negative for ZON metabolites. The maximum diet ratios for urine and bile in sows of the MYCO group were 0.84 and 0.05 for DON metabolites and 1.2 and 3.8 for ZON metabolites, underscoring the differences in metabolism and excretion of both toxins. The maximum diet ratio of DON and deepoxy-DON into liver, kidney and spleen of MYCO sows were 0.003, 0.007 and 0.003, respectively. The maximum fetus ratio of DON and deepoxy-DON into urine, bile, serum, liver and kidney of fetuses were 0.006, 0, 0.5, 0.88, and 0.33, while the maximum placental ratio (sum of toxin concentrations in the physiological specimen of the fetus divided by the toxin serum concentration of the sow) were 0.64, 0, 0.50, 0.70 and 0.52, respectively. Therefore, it can be concluded that the developing fetus is exposed to DON between the gestation days 35 and 70 when the sows are fed a Fusarium toxin contaminated diet. ZON concentration in the MYCO diet was too low to get reliable results for fetus or placental ratios.
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Affiliation(s)
- T Goyarts
- Institute of Animal Nutrition, Federal Agricultural Research Centre Braunschweig (FAL), Bundesallee 50, D-38116 Braunschweig, Germany
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Brandt Y, Madej A, Rodríguez-Martínez H, Einarsson S. Effects of exogenous ACTH during oestrus on early embryo development and oviductal transport in the sow. Reprod Domest Anim 2007; 42:118-25. [PMID: 17348967 DOI: 10.1111/j.1439-0531.2006.00698.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This study was conducted to assess the effects of ACTH injections on the early development of embryos and their transportation to the uterus. Fifteen sows were monitored for ovulation using transrectal ultrasonography during the first two oestrous periods after weaning. The sows were randomly divided into a control group (C group, n = 8) and an ACTH-treated group (ACTH group, n = 7), and were all surgically fitted with intra-jugular catheters. From the onset of the second standing oestrus after weaning, the sows were injected (NaCl/synthetic ACTH) every 4 h. Blood samples were collected immediately before and 45 min after each injection. All sows were inseminated once 10-33 h before ovulation in their second oestrus after weaning. At 48 (n = 4) or 60 (n = 11) h after ovulation during their second oestrus, the sows were killed and the embryos retrieved from the oviduct and uterus. The embryos were counted and compared with the number of corpora lutea, cleavage rate was noted and, finally, the embryos were prepared for confocal laser scanning microscopy and transmission electron microscopy. There was no difference between the groups regarding cleavage rate, the cytoskeleton, or the number of active nucleoli. However, the ACTH group had significantly (p < 0.05) fewer ova/embryos retrieved (51%) than the C group (81%), and there was a tendency towards faster transportation to the uterus in the ACTH group, possibly because of high progesterone concentrations during treatment. To conclude, administration of ACTH every 4 h from onset of oestrus to 48 h caused significant loss of oocytes or embryos, and possibly faster transportation through the oviduct.
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Affiliation(s)
- Y Brandt
- Division of Comparative Reproduction, Obstetrics and Udder Health, Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden.
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9
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Schneider F, Brüssow KP. Effects of a preovulatory administered depot gonadotrophin-releasing hormone agonist on reproductive hormone levels and pregnancy outcome in gilts. Reprod Fertil Dev 2007; 18:857-66. [PMID: 17147934 DOI: 10.1071/rd06027] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2006] [Accepted: 09/03/2006] [Indexed: 11/23/2022] Open
Abstract
The present study aimed to explore the influence of a preovulatory administered depot gonadotrophin-releasing hormone (GnRH) agonist (GnRHa; Decapeptyl Depot) on the endocrine parameters and pregnancy outcome of gilts (n = 6). A GnRHa-supported preovulatory luteinising hormone (LH) surge was detected in all treated gilts. LH pulses were abolished completely by depot GnRHa on Day 7 and partly on Day 21 of pregnancy. In this treatment group (n = 6) four gilts were pregnant at slaughter on Day 28. In the control group receiving Gonavet, a non-formulated GnRHa (n = 6), all pigs showed LH pulses and were pregnant at slaughter on Day 28 of gestation. Mean progesterone concentrations were elevated in controls during the early luteal phase and were similar for both groups during the implantation period. Mean concentration of unoccupied progesterone receptor was significantly higher in uterine myometrium than in endometrium, but without treatment effects. Peripheral estrone sulfate concentrations showed a similar increase in all pregnant gilts on Days 17 and 18, and remained elevated. In summary, treatment with a depot GnRHa for synchronisation of ovulation alters pulsatile LH secretion during early pregnancy in pigs. In general, this alteration seems not to exert an injurious influence on luteal function and, therefore, on embryo and early fetal development.
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Affiliation(s)
- F Schneider
- Department of Reproductive Biology, FBN Research Institute for the Biology of Farm Animals, D-18196 Dummerstorf, Germany.
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10
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Spitschak M, Langhammer M, Schneider F, Renne U, Vanselow J. Two high-fertility mouse lines show differences in component fertility traits after long-term selection. Reprod Fertil Dev 2007; 19:815-21. [PMID: 17897584 DOI: 10.1071/rd07009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2007] [Accepted: 05/25/2007] [Indexed: 11/23/2022] Open
Abstract
Two selected high-fertility mouse lines, namely FL1 and FL2, and a non-selected control (Fzt:DU), all derived from the same genetic pool, were analysed as an animal model for polytocous species to elucidate the effects of long-term selection and to identify relevant component traits that may be responsible for fertility performance. The index trait used for breeding selection was largely increased by 104% and 142% in the FL1 and FL2 lines, respectively, resulting in an average litter size of 17.3 pups and 18.7 pups per litter in the FL1 and FL2 lines, respectively, compared with a litter size of 11.0 pups per litter in the control (Fzt:DU). In addition, different component fertility traits were analysed in females of all three lines at different stages of the oestrous cycle and pregnancy. In conclusion: (1) early embryonic development was accelerated in the FL1 and FL2 lines compared with control; (2) plasma progesterone levels were not correlated with fertility performance; (3) a largely increased ovulation number (i.e. number of corpora lutea) was responsible for high prolificacy in both lines; however, (4) the number of ova shed, as well as the rate of loss of ova and pre- and postimplantation conceptuses, was very different in the FL1 and FL2 lines, suggesting that different genetic components may be responsible for the high prolificacy in both high-fertility lines.
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Affiliation(s)
- Marion Spitschak
- Forschungsbereich Molekularbiologie, Forschungsinstitut für die Biologie landwirtschaftlicher Nutztiere (FBN), Wilhelm-Stahl-Allee 2, Dummerstorf, Germany
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11
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Brüssow KP, Schneider F, Tuchscherer A, Rátky J, Kraeling RR, Kanitz W. Luteinizing hormone release after administration of the gonadotropin-releasing hormone agonist Fertilan (goserelin) for synchronization of ovulation in pigs. J Anim Sci 2007; 85:129-37. [PMID: 17179548 DOI: 10.2527/jas.2006-281] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The generic GnRH agonist, Fertilan (goserelin), was tested for the ability to induce an LH surge and ovulation in estrus-synchronized gilts. Three experiments were performed to 1) examine the effect of various doses of Fertilan on secretion of LH in barrows, to select doses to investigate in gilts (Exp. 1); 2) determine doses of Fertilan that would induce a preovulatory-like rise of LH in gilts (Exp. 2); and 3) determine the time of ovulation after Fertilan treatment (Exp. 3). In Exp. 1, 10 barrows were injected on d 1, 4, 7, 10, and 13 with 10, 20, or 40 microg of Fertilan; 50 microg of Gonavet (depherelin; GnRH control) or saline (negative control); and sequential blood samples were collected for 480 min. There was a dose-dependent stimulation (P < 0.05) of LH release. Maximal plasma concentrations of LH (LH(MAX)) were 2.1 +/- 0.2, 4.1 +/- 0.3, 2.6 +/- 0.4, and 3.4 +/- 0.3 ng/mL after 10, 20, and 40 microg of Fertilan and 50 microg of Gonavet, respectively, and duration of release was 78 +/- 9, 177 +/- 12, 138 +/- 7, and 180 +/- 11 min, respectively. Fertilan doses of 10 and 20 microg were deemed to be the most suitable for testing in gilts. In Exp. 2, 12 gilts received (after estrus synchronization with Regumate and eCG) injections of 10 or 20 microg of Fertilan or 50 microg of Gonavet 80 h after eCG to stimulate a preovulatory-like LH surge and ovulation. An LH surge was induced in 3 of the 4 gilts in both of the Fertilan groups and in all of the Gonavet-treated gilts. Characteristics of induced release of LH did not differ among groups: LH(MAX), 5.0 +/- 0.9 vs. 4.6 +/- 1.8 vs. 6.6 +/- 1.1 ng/mL; duration, 11.7 +/- 2.0 vs. 12.3 +/- 2.2 vs. 14.3 +/- 0.5 h; interval from GnRH injection to LH(MAX), 4.0 +/- 2.0 vs. 6.7 +/- 1.3 vs. 5.8 +/- 1.6 h. In Exp. 3, estrus-synchronized gilts were injected with 20 microg of Fertilan (n = 8) or 50 microg of Gonavet (n = 4), and the time of ovulation was determined by repeated endoscopic examination. Time of ovulation ranged from 34 to 42 h postGnRH; however, ovulation occurred earlier in the Gonavet compared with the other groups (P < 0.05). Results of these experiments indicate that 1) barrows are an appropriate model for determining GnRH doses that can be effective in inducing a preovulatory-like LH surge in females; 2) the generic GnRH agonist Fertilan, at doses of 10 to 20 microg, can stimulate an LH surge in gilts, with subsequent ovulation; and 3) Fertilan at doses of 10 and 20 microg should be examined further for use in fixed-time insemination protocols.
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Affiliation(s)
- K-P Brüssow
- FBN Research Institute for the Biology of Farm Animals, 18196 Dummerstorf, Germany.
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12
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Schneider F, Tomek W, Gründker C. Gonadotropin-releasing hormone (GnRH) and its natural analogues: a review. Theriogenology 2006; 66:691-709. [PMID: 16650469 DOI: 10.1016/j.theriogenology.2006.03.025] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2005] [Revised: 01/20/2006] [Accepted: 03/17/2006] [Indexed: 11/29/2022]
Abstract
The pivotal role of gonadotropin-releasing hormone (GnRH) during the hormonal regulation of reproductive processes is indisputable. Likewise, many factors are known to affect reproductive function by influencing either GnRH release from hypothalamus or pituitary gland responsiveness to GnRH. In veterinary medicine, GnRH and its agonists (GnRHa) are widely used to overcome reduced fertility by ovarian dysfunction, to induce ovulation, and to improve conception rate. GnRHa are, moreover, integrative part of other pro-fertility treatments, e.g. for synchronization of the estrous cycle or stimulation for embryo transfer. Additionally, continuous GnRH which shows desensitizing effects of the pituitary-ovarian axis has been recommended for implementation in anti-fertility treatments like inhibition of ovulation or reversible blockade of the estrous cycle. Just as much, another group of GnRH analogues, antagonists, are now in principle disposable for use. For a few decades, GnRH was thought to be a unique structure with a primary role in regulation gonadotropins. However, it became apparent that other homologous ligands of the GnRH receptor (GnRHR) exist. In the meantime, more than 20 natural variants of the mammalian GnRH have been identified in different species which may compete for binding and/or have their own receptors. These GnRH forms (GnRHs) have apparently common and divergent functions. More studies on GnRHs should contribute to a better understanding of reproductive processes in mammals and interactions between reproduction and other physiological functions. Increased information on GnRHs might raise expectations in the application of these peptides in veterinary practice. It is the aim of this review to discuss latest results from evolutionarily based studies as well as first experimental tests and to answer the question how realistic might be the efforts to develop effective and animal friendly practical applications for endogenous GnRHs and synthetic analogues.
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Affiliation(s)
- Falk Schneider
- Department of Reproductive Biology, Research Institute for the Biology of Farm Animals, Wilhelm-Stahl-Allee 2, D-18196 Dummerstorf, Germany.
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13
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Jarvis S, Moinard C, Robson SK, Baxter E, Ormandy E, Douglas AJ, Seckl JR, Russell JA, Lawrence AB. Programming the offspring of the pig by prenatal social stress: neuroendocrine activity and behaviour. Horm Behav 2006; 49:68-80. [PMID: 15961089 DOI: 10.1016/j.yhbeh.2005.05.004] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2005] [Revised: 04/29/2005] [Accepted: 05/03/2005] [Indexed: 10/25/2022]
Abstract
This study provides evidence in the pig that stress experienced during gestation has long-lasting effects on offspring daughters, including their maternal behaviour. Thirty-six primiparous sows were divided into control and two groups that were stressed (by social mixing) during either the second (Mix 2) or third (Mix 3) trimester of pregnancy. We found detrimental effects of mixing on the mothers' growth, body lesions, and cortisol secretion, but did not observe any significant effects on reproductive parameters including birth weight. At 60 days of age, 48 daughters were randomly selected from the three treatments: half were challenged using a restraint and isolation test. Then, all were culled and brain tissue was collected. In situ hybridisation measurements showed increased expression of CRH mRNA in the PVN in unrestrained Mix 2 and in the amygdala of Mix 2 and Mix 3 daughters. At 67 days, 24 further daughters were mixed to measure their responses to this social stress. All showed increased salivary cortisol secretion, but Mix 2 and Mix 3 daughters showed a greater and longer response than controls. Finally, all 24 were inseminated and at parturition maternal behaviour was measured. Mix 2 and Mix 3 daughters were more restless and more responsive to piglets that approached the head of the sow, traits which previously have been shown to be a component of abnormal maternal behaviour. Indeed, Mix 2 and Mix 3 daughters also tended to bite at their piglets more than control daughters.
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Affiliation(s)
- Susan Jarvis
- Animal Behaviour and Welfare, Sustainable Livestock Systems, Scottish Agricultural College, Edinburgh, UK.
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14
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Brüssow KP, Schneider F, Kanitz E, Otten W, Tuchscherer M. Alteration of Reproductive Hormone Levels in Pregnant Sows Induced by Repeated ACTH Application and Its Possible Influence on Pre- and Post-natal Hormone Secretion of Piglets. J Reprod Dev 2005; 51:133-42. [PMID: 15750305 DOI: 10.1262/jrd.51.133] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Prenatal stress has been seen as a reason for reproductive failures in pig offspring mostly originated or mediated by changed maternal functions. Experiments were conducted in pregnant gilts (n=32) to characterize effects of elevated maternal glucocorticoids on the secretion of reproductive hormones (LH, progesterone) during the 1st (EXP 1), 2nd (EXP 2) and 3rd (EXP 3) trimester of pregnancy (TP). Transiently elevated cortisol release was repeatedly achieved by application of 100 IU adenocorticotropic hormone (ACTH) (Synacthen Depot) six times every second day beginning either on day 28 (EXP 1), day 49 (EXP 2) or day 75 of pregnancy (EXP 3). Glucocorticoid concentrations were examined in umbilical blood vessels of fetuses which mothers were subjected to ACTH at 2nd and 3rd TP (EXP 4). Furthermore, the pituitary function of newborn piglets of EXP 2 was checked by a LH-RH challenge test. In sows, LH concentrations were at low basal level (0.1-0.2 ng/ml) but with pulsatory release pattern during each TP. The number of LH pulses/6 h (LSM +/- SE) of saline treated Controls increased with ongoing pregnancy and decreased to the 3rd TP (1.3 +/- 0.2 in EXP 1 vs. 2.0 +/- 0.1 in EXP 2 vs. 1.4 +/- 0.1 in EXP 3, p<0.05). After ACTH treatment the number of LH pulses left unchanged in Experiments 1 and 2 (1.3 +/- 0.2 and 1.5 +/- 0.1) and decreased in EXP 3 (0.8 +/- 0.2, p<0.05). Differences (p<0.05) were obtained comparing the LH pulse number of ACTH and saline treated sows at the 2nd and 3rd TP. Moreover, areas under the curve (AUC) of each LH pulse and of LH over baseline were significantly reduced by treatment. Levels of progesterone increased (p<0.05) for 150 to 170 min after each ACTH application both in EXP 1 and EXP 2, but not in EXP 3. The mean progesterone concentration was different between trimesters, and ACTH and Controls (1st TP: 30.0 +/- 0.9 and 24.4 +/- 0.7 ng/ml; 2nd TP: 35.5 +/- 0.9 and 29.1 +/- 1.0 ng/ml; 3rd TP: 13.6 +/- 0.2 and 13.1 +/- 0.1 ng/ml; p<0.05). In fetuses (n=87) recovered 3 h after ACTH or saline (EXP 4), the plasma cortisol concentrations were significantly increased in umbilical vein (93.7 +/- 5.5 vs. 47.0 +/- 5.3 nmol/l) and artery (95.7 +/- 5.4 vs. 66.4 +/- 5.4 nmol/l), and in periphery (46.8 +/- 5.3 vs. 27.1 +/- 5.3 nmol/l) compared to controls. Plasma ACTH concentrations, however, did not differ in fetuses of both treatment groups. Postnatal LH-RH challenge tests (1st and 28th day post partum) induced LH surges in female piglets (n=67) both of ACTH and saline treated sows, but did not differ between groups (1st day: 7.2 +/- 0.8 vs. 8.1 +/- 0.7 ng/ml; 28th day: 10.5 +/- 1.7 vs. 13.6 +/- 2.2 ng/ml). However, basal LH of piglets whose mothers were submitted to ACTH during 2nd TP was lower on 1st day (1.7 +/- 0.2 vs. 2.3 +/- 0.2 ng/ml, p<0.05) but not on 28th day (1.0 +/- 0.2 vs. 1.1 +/- 0.2 ng/ml). However in both groups, the basal LH was always higher on 1st as on 28th day (p<0.05). Thus, chronic intermittent ACTH administration is able to influence the release pattern of maternal reproductive hormones. However, these findings demonstrate that these effects are dependent on the stage of pregnancy. Furthermore, it was shown that maternal cortisol can cross the placenta during gestation and thus may affect maternal-fetal interactions and, as a result, reproductive function of offspring.
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Affiliation(s)
- Klaus-Peter Brüssow
- Department of Reproductive Biology, Research Institute for the Biology of Farm Animals, Dummerstof, Germany.
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