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Antti Iivanainen - One of the best experts on this subject based on the ideXlab platform.
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Direct observation of hematopoietic progenitor chimerism in fetal Freemartin cattle
BMC Veterinary Research, 2007Co-Authors: Mikael Niku, Tiina Pessa-morikawa, Juhani Taponen, Antti IivanainenAbstract:Background Cattle twins are well known as blood chimeras. However, chimerism in the actual hematopoietic progenitor compartment has not been directly investigated. Here, we analyzed fetal liver of chimeric Freemartin cattle by combining a new anti-bovine CD34 antibody and Y-chromosome specific in situ hybridization. Results Bull-derived CD34^+ cells were detected in the liver of the female sibling (Freemartin) at 60 days gestation. The level of bull-derived CD34^+ cells was lower in the Freemartin than in its male siblings. Bull (Y^+) and cow hematopoietic cells often occurred in separate clusters. Around clusters of Y^+CD34^+ cells, Y^+CD34^- cells were typically observed. The thymi were also strongly chimeric at 60 days of gestation. Conclusion The fetal Freemartin liver contains clusters of bull-derived hematopoietic progenitors, suggesting clonal expansion and differentiation. Even the roots of the hematopoietic system in cattle twins are thus strongly chimeric from the early stages of fetal development. However, the hematopoietic seeding of fetal liver apparently started already before the onset of functional vascular anastomosis.
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direct observation of hematopoietic progenitor chimerism in fetal Freemartin cattle
BMC Veterinary Research, 2007Co-Authors: Mikael Niku, Juhani Taponen, Tiina Pessamorikawa, Antti IivanainenAbstract:Background Cattle twins are well known as blood chimeras. However, chimerism in the actual hematopoietic progenitor compartment has not been directly investigated. Here, we analyzed fetal liver of chimeric Freemartin cattle by combining a new anti-bovine CD34 antibody and Y-chromosome specific in situ hybridization.
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persistent differences in the level of chimerism in b versus t cells of Freemartin cattle
Developmental and Comparative Immunology, 2004Co-Authors: Tiina Pessamorikawa, Mikael Niku, Antti IivanainenAbstract:Abstract Parabiosis during pregnancy regularly results in an exchange of hematopoietic stem cells between cattle twins. We have exploited this phenomenon and show differences in the levels of chimerism between the descendant cell types. Female recipients were screened for the levels of male donor contribution in surface IgM-bearing B lymphocytes versus CD3 + T lymphocytes using immunomagnetic fractionation and Y-chromosome specific in situ hybridization. Two calves of 15 were discovered to have less than 10% of B cells but over 70% of T cells and other blood leukocytes of male origin. The donor cell ratios remained stable for 9 months. Analysis of lymphoid tissues revealed a similar cell type specific pattern of male cell ratios in both female calves and one twin brother. These findings are in agreement with the existence of an essentially self-sufficient population of developing B cells that gives rise to the peripheral pool of B lymphocytes in young cattle.
Bruno Cozzi - One of the best experts on this subject based on the ideXlab platform.
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Expression of AMH in female fetal intersex gonads in the bovine.
Anatomia Histologia Embryologia, 2006Co-Authors: G. Cabianca, Ada Rota, Bruno Cozzi, Cristina BallarinAbstract:Summary Anti Mullerian Hormone, AMH, is believed to be the main agent in the Freemartin syndrome. Supposing an active role of Freemartin gonads in AMH secretion, in the present study, we aimed at investigating the presence and the localization of AMH producing cells either in fetal or in adult Freemartin gonads. Our finding of positive AMH cells in a 26-week-old Freemartin fetus indicates an active role of masculinized Freemartin gonads in AMH secretion. However, the positive reaction, limited to few cells grouped in ‘nests’ in proximity to testis cord-like structures, supports a chimeric origin of such cells, migrated from the male co-twin. No adult Freemartin, irrespective from the degree of masculinization, showed any AMH positive cell.
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age dependent changes in plasma anti mullerian hormone concentrations in the bovine male female and Freemartin from birth to puberty relationship between testosterone production and influence on sex differentiation
General and Comparative Endocrinology, 2002Co-Authors: Ada Rota, B. Vigier, Cristina Ballarin, Bruno CozziAbstract:To understand the behaviour of the gonads, in terms of hormonal secretion, in a model of intersexual development naturally occurring in mammals, we determined plasma concentrations of testosterone, progesterone, and anti-Mullerian hormone (AMH) in bovine Freemartins, and compared them to normal levels measured in males and females from birth to puberty. We found that newborn males and Freemartins have very high concentrations of AMH (over 700 ng/ml). Conversely, plasma AMH concentration is always below 120 ng/ml in females. While values remain stable in males for the first five months of life, they sharply decrease in the Freemartins within the first fortnight, and reach female levels, which demonstrates that AMH is essentially originated in the male twin. In young bulls the trend of plasma testosterone concentrations is opposite to that of the AMH. The rise in testosterone production at puberty corresponds to a sharp decline in AMH concentrations. Bovine plasma concentrations of AMH are surprisingly higher than those measured in other mammals, including man and mouse. The results obtained are discussed in reference to comparative aspects of endocrine functions.
Huawei Su - One of the best experts on this subject based on the ideXlab platform.
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applying real time quantitative pcr to diagnosis of Freemartin in holstein cattle by quantifying sry gene a comparison experiment
PeerJ, 2018Co-Authors: Taoqi Shao, Yang He, Azizurrahman Muhammad, Huawei SuAbstract:Background: Freemartinism generally occurs in female offspring of dizygotic twins in a mixed-sex pregnancy. Most bovine heterosexual twin females are Freemartins. However, about 10% of bovine heterosexual twin females are fertile. Farmers mostly cull bovine fertile heterosexual twin females due to the lack of a practical diagnostic approach. Culling of such animals results in economic and genetic-material losses both for dairy and beef industry. Methods: In this study, a comparative test, including qualitative detection of SRY gene by polymerase chain reaction (PCR), quantitative detection of relative content of SRY by real-time quantitative polymerase chain reaction (qPCR), and quantitative detection of H-Y antigen, was performed to establish the most accurate diagnosis for Freemartin. Twelve Holstein heterosexual twin females were used in this study, while three normal Holstein bulls and three normal Holstein cows were used as a positive and negative control, respectively. Results: Polymerase chain reaction results revealed that SRY gene were absent in three heterosexual twin females and only two of them were verified as fertile in later age. The qPCR results showed that relative content of SRY was more than 14.2% in Freemartins and below 0.41% in fertile heterosexual twin females. The H-Y antigen test showed no significant numerical difference between Freemartin and fertile heterosexual twin female. Discussion: Our results show that relative content of SRY quantified by qPCR is a better detection method for diagnosis of Freemartin in Holstein cattle as compare to qualitative detection of SRY gene by PCR or quantitative detection of H-Y antigen. To the authors' knowledge, this is the first time we applied qPCR to diagnosing Freemartin by quantifying SRY gene and got relative SRY content of each Freemartin and fertile heterosexual twin female. We concluded that low-level of SRY would not influence fertility of bovine heterosexual twin female.
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dietary alfalfa and calcium salts of long chain fatty acids alter protein utilization microbial populations and plasma fatty acid profile in holstein Freemartin heifers
Journal of Agricultural and Food Chemistry, 2017Co-Authors: Yang He, Taoqi Shao, Haibo Wang, Qianwen Li, Zhantao Yu, Huawei SuAbstract:This study presented the effects of alfalfa and calcium salts of long-chain fatty acids (CSFA) on feed intake, apparent digestibility, rumen fermentation, microbial community, plasma biochemical parameters, and fatty acid profile in Holstein Freemartin heifers. Eight Holstein Freemartin heifers were randomly divided into a 4 × 4 Latin Square experiment with 2 × 2 factorial diets, with or without alfalfa or CSFA. Dietary supplementation of CSFA significantly increased the apparent digestibility of dry matter, crude protein, neutral detergent fiber, organic matter, and significantly reduced N retention (P < 0.05). CSFA increased the concentration of ammonia nitrogen in the ruminal fluid (P < 0.05), but alfalfa increased the concentration of valerate and isovalerate (P < 0.05). CSFA increased the concentration of ammonia nitrogen and the relative population of Streptococcus bovis in the rumen (P < 0.05) and inhibited the relative population of Ruminococcus flavefaciens, methanogens, and protozoa (P < 0.05). ...
B. Vigier - One of the best experts on this subject based on the ideXlab platform.
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age dependent changes in plasma anti mullerian hormone concentrations in the bovine male female and Freemartin from birth to puberty relationship between testosterone production and influence on sex differentiation
General and Comparative Endocrinology, 2002Co-Authors: Ada Rota, B. Vigier, Cristina Ballarin, Bruno CozziAbstract:To understand the behaviour of the gonads, in terms of hormonal secretion, in a model of intersexual development naturally occurring in mammals, we determined plasma concentrations of testosterone, progesterone, and anti-Mullerian hormone (AMH) in bovine Freemartins, and compared them to normal levels measured in males and females from birth to puberty. We found that newborn males and Freemartins have very high concentrations of AMH (over 700 ng/ml). Conversely, plasma AMH concentration is always below 120 ng/ml in females. While values remain stable in males for the first five months of life, they sharply decrease in the Freemartins within the first fortnight, and reach female levels, which demonstrates that AMH is essentially originated in the male twin. In young bulls the trend of plasma testosterone concentrations is opposite to that of the AMH. The rise in testosterone production at puberty corresponds to a sharp decline in AMH concentrations. Bovine plasma concentrations of AMH are surprisingly higher than those measured in other mammals, including man and mouse. The results obtained are discussed in reference to comparative aspects of endocrine functions.
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Ontogeny of reproductive abnormalities induced by deregulation of anti-müllerian hormone expression in transgenic mice.
Biology of Reproduction, 1995Co-Authors: Lionel Lyet, Franck Louis, Maguelone G. Forest, Nathalie Josso, Richard R. Behringer, B. VigierAbstract:Anti-Millerian hormone, normally responsible for the regression of Muillerian ducts in male fetuses, induces stunting, germ cell loss, and seminiferous tubule formation in ovaries of bovine Freemartin fetuses and of transgenic mice, which express the human anti-Muillerian hormone gene under the control of the metallothionein promoter. Because the latter have been studied only after birth, we undertook a detailed chronological study of their reproductive organs. Muillerian ducts of transgenic female fetuses regressed at the same time as those of normal or transgenic males. Maximal reduction of germ cell number occurred between 16 days postcoitus and birth, when most transgenic oocytes were still in the leptotene stage of the meiotic prophase, whereas normal oocytes had already reached the pachytene phase. Interference with progression of the meiotic prophase and germ cell loss in the fetal ovary are probably responsible for subsequent ovarian regression and retardation of follicle growth. Seminiferous tubule formation was not detectable prior to birth and occurred only rarely in postnatal ovaries. Aromatase activity of fetal transgenic ovaries was decreased, as well as serum concentration of testosterone in adult transgenic males, suggesting that high levels of anti-Millerian hormone may impair Leydig cell steroidogenesis.
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Development of the gubernaculum and processus vaginalis in Freemartinism: further evidence in support of a specific fetal testis hormone governing male-specific gubernacular development.
Anatomical Record-advances in Integrative Anatomy and Evolutionary Biology, 1995Co-Authors: Pieter Van Der Schoot, B. Vigier, Jaques Prepin, Jean-pierre Perchellet, Adriana C. Gittenberger-de GrootAbstract:Background: Freemartinism occurs in some speices of ruminants and affects most female bovine fetuses in hterrosexual, multiple pregnancies owing of susion of the chorionic blood circulations soon after implantation. Maldevelopment of the ovaries and Mullerian ducts have been described and recognized as resulting from exposure of their respective primoridia to an excess of anti-Mullerian hormone. The Present study aimed to analyse the prenatal growth the development of the gubernaculum in Freemartins to find out its pssible affliction through foetal testis hormones derived from their male co-twin. Methods: Histolgical sections of young and frawings and photographs of further developed Freemartins and conrol male and female bovine foeuses were analysed. The specimens had been collected ealier for analsis of the time course of male and female gonadal and gential development and its impairment associated with Freemartinism. Results: The gubernaculum of 35–40 day-old male and female fetuses was in the intial stage of development and of similar appearance in all specimens. Gubenacula of 60–70-day-old male fetuss differed from those of females of similar age in various respects: the male gubernaculum size was larger and extension of the processus vaginalis was deeper. Freemartins showd and intermediate development with some individuals resembling male and othes resembling female agemates. During furher development, gubernacula in males developed into muscular cremaster sacs, whereas those in females generally did not develop beyond the size and structural complexity of 70-day-old foetuses. Beyond day 70 of fetal life, gubernaculum development in Freemartins definitly showed male characteristics with respect to size and growth of a processus vaginalis with a cremaster muscular wall. The male-like pattern of the outgrowth of the processus vainalis changed during the second half of prenatal life. Rather than its further deepening as in mals, this structure became inveted to become emerging as a papilla-like structure from the inguinal abdomen bottom. An explanation is proposed for this unprecedented inversion, taking into account: (1) the faster and higher reaching rightsided ascent of the kidneys and gonads, (2) the femalelike outgrowth of the cranial gonadal suspensory ligaments, and (3) the absence of scrotum development. The ovaries and mesonephric remnants in developing Freemartins, during their ascent together with the kidneys while remaining attached to the bottom of the developing processus vaginalis sacs via the gubernaculum ligament, are proposed to act together to pull up the bottom of the processus vaginalis sacs. From this action, “inverted hernia sacs” result as the irreversible consequence. Conclusion: The data support the concept that foetal testes act, via as an yet unidentified third hormone, to establish malelike development of gubernacula into muscular cremaster sacs. Further work is required to reveal the identity of this hormone. Furthermore, the apparent similarity of the Freemartins' inverted processus vaginalis sacs and the fetal rodents' gubernacular cones suggests that the ruminants' and rodents' processus vaginalis are essentially similar structures. Thus there is no longer an urgent need to distinguish between two different types of gubernaculum development and testis descent in rodents and ruminants, respectively, and involving or not fetal gubernacular cones. The present observations may thus contribute to the development of a unified hypothesis for sexually dimorphic development of the gubernaculum throughout the mammalian class. © 1995 Wiley-Liss, Inc.
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anti mullerian hormone and natural and experimental Freemartin effect
Bulletin de l'Association des anatomistes, 1991Co-Authors: B. Vigier, S Magre, G Charpentier, Jacqueline Bezard, Nathalie JossoAbstract:: To determine whether anti-Mullerian hormone (AMH) is responsible for the gonadal anomalies observed in bovine female "Freemartins" united by placental anastomosis to a male twin, fetal rat and ovine prospective ovaries were exposed to purified bovine AMH in organ culture. We show that AMH reproduces the caracteristical "Freemartin effect"; namely the initial inhibition of gonadal and germ cell development, and the differentiation of fetal Sertoli cells forming seminiferous cord-like structures and producing immuno and bioactive AMH. In addition, fetal ovine ovaries submitted to AMH release testosterone instead of estradiol due to an inhibiting effect upon the biosynthesis of their aromatase enzyme. Taken together, these results indicate that AMH is probably the testicular factor responsible for the abnormalities of Freemartin gonads and suggest that this hormone could play a pivotal role in normal testis differentiation.
Mikael Niku - One of the best experts on this subject based on the ideXlab platform.
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Direct observation of hematopoietic progenitor chimerism in fetal Freemartin cattle
BMC Veterinary Research, 2007Co-Authors: Mikael Niku, Tiina Pessa-morikawa, Juhani Taponen, Antti IivanainenAbstract:Background Cattle twins are well known as blood chimeras. However, chimerism in the actual hematopoietic progenitor compartment has not been directly investigated. Here, we analyzed fetal liver of chimeric Freemartin cattle by combining a new anti-bovine CD34 antibody and Y-chromosome specific in situ hybridization. Results Bull-derived CD34^+ cells were detected in the liver of the female sibling (Freemartin) at 60 days gestation. The level of bull-derived CD34^+ cells was lower in the Freemartin than in its male siblings. Bull (Y^+) and cow hematopoietic cells often occurred in separate clusters. Around clusters of Y^+CD34^+ cells, Y^+CD34^- cells were typically observed. The thymi were also strongly chimeric at 60 days of gestation. Conclusion The fetal Freemartin liver contains clusters of bull-derived hematopoietic progenitors, suggesting clonal expansion and differentiation. Even the roots of the hematopoietic system in cattle twins are thus strongly chimeric from the early stages of fetal development. However, the hematopoietic seeding of fetal liver apparently started already before the onset of functional vascular anastomosis.
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direct observation of hematopoietic progenitor chimerism in fetal Freemartin cattle
BMC Veterinary Research, 2007Co-Authors: Mikael Niku, Juhani Taponen, Tiina Pessamorikawa, Antti IivanainenAbstract:Background Cattle twins are well known as blood chimeras. However, chimerism in the actual hematopoietic progenitor compartment has not been directly investigated. Here, we analyzed fetal liver of chimeric Freemartin cattle by combining a new anti-bovine CD34 antibody and Y-chromosome specific in situ hybridization.
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persistent differences in the level of chimerism in b versus t cells of Freemartin cattle
Developmental and Comparative Immunology, 2004Co-Authors: Tiina Pessamorikawa, Mikael Niku, Antti IivanainenAbstract:Abstract Parabiosis during pregnancy regularly results in an exchange of hematopoietic stem cells between cattle twins. We have exploited this phenomenon and show differences in the levels of chimerism between the descendant cell types. Female recipients were screened for the levels of male donor contribution in surface IgM-bearing B lymphocytes versus CD3 + T lymphocytes using immunomagnetic fractionation and Y-chromosome specific in situ hybridization. Two calves of 15 were discovered to have less than 10% of B cells but over 70% of T cells and other blood leukocytes of male origin. The donor cell ratios remained stable for 9 months. Analysis of lymphoid tissues revealed a similar cell type specific pattern of male cell ratios in both female calves and one twin brother. These findings are in agreement with the existence of an essentially self-sufficient population of developing B cells that gives rise to the peripheral pool of B lymphocytes in young cattle.
