A freemartin or free-martin (sometimes martin heifer) is an infertilefemalecattle with masculinized behavior and non-functioning ovaries.[1] Phenotypically, the animal appears female, but various aspects of female reproductive development are altered due to acquisition of anti-Müllerian hormone from the male twin.[2] Genetically, the animal is chimeric: karyotypy of a sample of cells shows XX/XY chromosomes. The animal originates as a female (XX), but acquires the male (XY) component in utero by exchange of some cellular material from a male twin, via vascular connections between placentas: an example of microchimerism.[3] The chimerism is mainly present in the hematopoietic stem cells.[4]
A plate showing a "Free Martin" from the collected works of John Hunter.
Freemartins are known to have been described by the Roman writer Varro, who called them "taura".[5]
The 18th-century physician John Hunter discovered that a freemartin always has a male twin.[6]
It was hypothesized early in the 20th century that masculinizing factors travel from the male twin to the female twin through the vascular connections of the placenta because of the vascular fusion and affect the internal anatomy of the female.[7]
Several researchers made the discovery that a freemartin results when a female fetus has its chorion fuse in the uterus with that of a male twin. The result was published in 1916 by Tandler and Keller.[8] The discovery was made independently by American biologist Frank R. Lillie, who published it in Science in 1916.[9] Both teams are now credited with the discovery.[10]
In rural areas folklore often claimed this condition was not just peculiar to cattle, but extended also to human twins; this belief perpetuated for generations, as was mentioned in the writings of Cuthbert Bede.[11]
Etymologyedit
The etymology of the term "freemartin" is uncertain: speculations include that "free" may indicate "willing" (referring to the freemartin's willingness to work) or "exempt from reproduction" (referring to its sterility, or to a farmer's decision to not bother trying to breed a freemartin, or both), or that it may be derived from a Flemish word for a cow which gives no milk and/or has ceased to be capable of bearing offspring;[5] "martin" is generally held to derive from an Irish or Gaelic word for "cow" or "heifer", although connections to Martinmas have also been posited.[5]
Mechanismedit
In most cattle twins, the blood vessels in the chorions become interconnected, creating a shared circulation for both twins. If both fetuses are the same sex this is of no significance, but if they are different, male hormones pass from the male twin to the female twin. The male hormones (testosterone and anti-Müllerian hormone) then masculinize the female twin, and the result is a freemartin.[12] The degree of masculinization is greater if the fusion occurs earlier in the pregnancy – in about ten percent of cases no fusion takes place and the female remains fertile.
The male twin is largely unaffected by the fusion, although the size of the testicles may be slightly reduced. Testicle size is associated with fertility, so there may be some reduction in bull fertility.
Freemartins behave and grow in a similar way to castrated male cattle (steers).
Diagnosisedit
If suspected, a test can be done to detect the presence of the male Y-chromosomes in some circulating white blood cells of the subject. Genetic testing for the Y-chromosome can be performed within days of birth and can aid in the early identification of a sterile female bovine.
Physical examination of the calf may also reveal differences: a subjective assessment is that frequently there is a lengthened tuft of hair at the ventral tip of the vulva in a freemartin heifer atypical in fertile heifer calves. Also, often many (but not all) freemartins will have a shortened length of vagina compared with that of a fertile heifer. Commercial probes are available to check heifers for obvious freemartinism in lieu of doing a blood test [13]
Other animalsedit
A freemartin is the normal outcome of mixed twins in all cattle species which have been studied. It does not normally occur in most other mammals, though it has been recorded in sheep,[14]goats,[15] and pigs.[16]
Usesedit
Freemartins are occasionally used in stem cell and immunology research.[17] During fetal development cells are exchanged between the fused circulations of the bovine twins. Up to 95% of the freemartin's blood cells can be derived from those of her twin brother. Male-derived cells and their progeny can be easily visualised in the freemartin tissues, as only they contain the male Y chromosome. Thus, by analysing these tissues, one can investigate the capacity of hematopoietic stem cells or other circulating cells to produce other tissues in addition to blood. The freemartin model allows one to analyse perfectly healthy and unmanipulated animals, without resorting to transplantation often used in stem cell research.
Fictional useedit
In the Aldous Huxley novel Brave New World, a "freemartin" (mentioned in chapters 1, 3, 11 and 17) is a woman who has been deliberately made sterile by exposure to hormones during fetal development; in the book, government policy requires freemartins to constitute 70% of the female population. A side effect of this is some freemartin women having developed beards.
The Robert A. Heinlein novel Beyond This Horizon lists "the clever and repulsively beautiful pseudo-feminine freemartins" as one of the genetically-engineered specialist types of humans that were created in the "Empire of the Great Khans" (chapter 2).
In the Robert Heinlein novel Farnham's Freehold, the protagonist, Hugh Farnham, is given a companion ("bedwarmer") that is described as a "natural freemartin".
In the Avram Davidson story "The House the Blakeneys Built", the cattle are freemartins.
In Footfall by Larry Niven and Jerry Pournelle, a lithely-built human woman uses the term "freemartin" to describe herself, while doubting her sexuality.
In Nicola Griffith's novel Hild, the title character is sometimes referred to by others as a freemartin, in reference to her non-feminine character and social role.
In Lauren Groff's novel Matrix (New York: Riverhead Books, 2021), 12th-century English peasants use freemartins to pull wagons.
^Rota A, Ballarin C, Vigier B, Cozzi B, Rey R (October 2002). "Age dependent changes in plasma anti-Müllerian 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. 129 (1): 39–44. doi:10.1016/S0016-6480(02)00514-2. PMID 12409094.{{cite journal}}: CS1 maint: multiple names: authors list (link)
^In utero cell transfer between porcine littermates, in Reproduction, Fertility, and Development (2011; 23(2): 297–302. - doi: 10.1071/RD10165)
^"9 - Abnormalities of Development and Pregnancy". Veterinary reproduction and obstetrics. David E. Noakes, Timothy J. Parkinson, Gary C. W. England (Tenth ed.). [Edinburgh, Scotland]. 2019. pp. 168–194. doi:10.1016/B978-0-7020-7233-8.00009-4. ISBN978-0-7020-7238-3. OCLC 1077474208. S2CID 81828645.{{cite book}}: CS1 maint: location missing publisher (link) CS1 maint: others (link)
^ abcEARLY RECOGNITION OF THE FREEMARTIN CONDITION IN HEIFERS TWINBORN WITH BULLS, by W.W. Swett, C.A. Matthews, and R. R. Graves, in the Journal of Agricultural Research, vol. 61, no. 8 (October 15, 1940)
^Hunter, John (1779). "Account of the Free Martin. By Mr. John Hunter, F. R. S." Philosophical Transactions of the Royal Society of London. 69: 279–93. Bibcode:1779RSPT...69..279H. doi:10.1098/rstl.1779.0020. JSTOR 106420.
^(Nelson, Randy. An introduction to behavioral endocrinology. Sinauer Associates: Massachusetts. 2005: pg 145)
^Keller, K. and Tandler, J.: Wiener Tieraztl. Wochensch., 3, 513-526 (1916).[verification needed]
^Lillie FR (April 1916). "The Theory of the Free-Martin". Science. 43 (1113): 611–3. Bibcode:1916Sci....43..611L. doi:10.1126/science.43.1113.611. JSTOR 1641047. PMID 17756274.
^Freeman G (March 2007). "Explaining the freemartin: Tandler and Keller vs. Lillie and the question of priority". Journal of Experimental Zoology B. 308 (2): 105–12. doi:10.1002/jez.b.21151. PMID 17219370.
^Cuthbert Bede (1859–1860). "The folk-lore of a country parish". Once a Week. 1. Vol. 2. Bradbury & Evans. If twins are born in our country parish, it is believed that of the little bipeds—like the quadrupedal martin-heifers and free-martins—only one will prove the father (or mother) of a family.
^Padula AM (June 2005). "The freemartin syndrome: an update". Animal Reproduction Science. 87 (1–2): 93–109. doi:10.1016/j.anireprosci.2004.09.008. PMID 15885443.
^Eldridge FE, Blazak WF (March 1977). "Chromosomal analysis of fertile female heterosexual twins in cattle". Journal of Dairy Science. 60 (3): 458–63. doi:10.3168/jds.S0022-0302(77)83888-5. PMID 845292.
^Wilkes PR, Munro IB, Wijeratne WV (February 1978). "Studies on a sheep freemartin". The Veterinary Record. 102 (7): 140–2. doi:10.1136/vr.102.7.140. PMID 565559. S2CID 43776725.{{cite journal}}: CS1 maint: multiple names: authors list (link)
^Ilbery PL, Williams D (1967). "Evidence of the freemartin condition in the goat". Cytogenetics. 6 (3): 276–85. doi:10.1159/000129948. PMID 6035567.
^Bruere AN, Fielden ED, Hutchings H (March 1968). "XX-XY mosaicism in lymphocyte cultures from a pig with freemartin characteristics". New Zealand Veterinary Journal. 16 (3): 31–8. doi:10.1080/00480169.1968.33743. PMID 5241942.{{cite journal}}: CS1 maint: multiple names: authors list (link)
^Niku M, Ilmonen L, Pessa-Morikawa T, Iivanainen A (2004). "Limited contribution of circulating cells to the development and maintenance of nonhematopoietic bovine tissues". Stem Cells. 22 (1): 12–20. doi:10.1634/stemcells.22-1-12. PMID 14688387. S2CID 13556114.{{cite journal}}: CS1 maint: multiple names: authors list (link)
External linksedit
Mosaicism and Chimerism at colostate.edu 2006-03-30 at the Wayback Machine
Picture at agric.gov.ab.ca 2019-02-24 at the Wayback Machine
November 11, 2023
freemartin, freemartin, free, martin, sometimes, martin, heifer, infertile, female, cattle, with, masculinized, behavior, functioning, ovaries, phenotypically, animal, appears, female, various, aspects, female, reproductive, development, altered, acquisition, . A freemartin or free martin sometimes martin heifer is an infertile female cattle with masculinized behavior and non functioning ovaries 1 Phenotypically the animal appears female but various aspects of female reproductive development are altered due to acquisition of anti Mullerian hormone from the male twin 2 Genetically the animal is chimeric karyotypy of a sample of cells shows XX XY chromosomes The animal originates as a female XX but acquires the male XY component in utero by exchange of some cellular material from a male twin via vascular connections between placentas an example of microchimerism 3 The chimerism is mainly present in the hematopoietic stem cells 4 A plate showing a Free Martin from the collected works of John Hunter Contents 1 History 1 1 Etymology 2 Mechanism 3 Diagnosis 4 Other animals 5 Uses 6 Fictional use 7 References 8 External linksHistory editFreemartins are known to have been described by the Roman writer Varro who called them taura 5 The 18th century physician John Hunter discovered that a freemartin always has a male twin 6 It was hypothesized early in the 20th century that masculinizing factors travel from the male twin to the female twin through the vascular connections of the placenta because of the vascular fusion and affect the internal anatomy of the female 7 Several researchers made the discovery that a freemartin results when a female fetus has its chorion fuse in the uterus with that of a male twin The result was published in 1916 by Tandler and Keller 8 The discovery was made independently by American biologist Frank R Lillie who published it in Science in 1916 9 Both teams are now credited with the discovery 10 In rural areas folklore often claimed this condition was not just peculiar to cattle but extended also to human twins this belief perpetuated for generations as was mentioned in the writings of Cuthbert Bede 11 Etymology edit The etymology of the term freemartin is uncertain speculations include that free may indicate willing referring to the freemartin s willingness to work or exempt from reproduction referring to its sterility or to a farmer s decision to not bother trying to breed a freemartin or both or that it may be derived from a Flemish word for a cow which gives no milk and or has ceased to be capable of bearing offspring 5 martin is generally held to derive from an Irish or Gaelic word for cow or heifer although connections to Martinmas have also been posited 5 Mechanism editIn most cattle twins the blood vessels in the chorions become interconnected creating a shared circulation for both twins If both fetuses are the same sex this is of no significance but if they are different male hormones pass from the male twin to the female twin The male hormones testosterone and anti Mullerian hormone then masculinize the female twin and the result is a freemartin 12 The degree of masculinization is greater if the fusion occurs earlier in the pregnancy in about ten percent of cases no fusion takes place and the female remains fertile The male twin is largely unaffected by the fusion although the size of the testicles may be slightly reduced Testicle size is associated with fertility so there may be some reduction in bull fertility Freemartins behave and grow in a similar way to castrated male cattle steers Diagnosis editIf suspected a test can be done to detect the presence of the male Y chromosomes in some circulating white blood cells of the subject Genetic testing for the Y chromosome can be performed within days of birth and can aid in the early identification of a sterile female bovine Physical examination of the calf may also reveal differences a subjective assessment is that frequently there is a lengthened tuft of hair at the ventral tip of the vulva in a freemartin heifer atypical in fertile heifer calves Also often many but not all freemartins will have a shortened length of vagina compared with that of a fertile heifer Commercial probes are available to check heifers for obvious freemartinism in lieu of doing a blood test 13 Other animals editA freemartin is the normal outcome of mixed twins in all cattle species which have been studied It does not normally occur in most other mammals though it has been recorded in sheep 14 goats 15 and pigs 16 Uses editFreemartins are occasionally used in stem cell and immunology research 17 During fetal development cells are exchanged between the fused circulations of the bovine twins Up to 95 of the freemartin s blood cells can be derived from those of her twin brother Male derived cells and their progeny can be easily visualised in the freemartin tissues as only they contain the male Y chromosome Thus by analysing these tissues one can investigate the capacity of hematopoietic stem cells or other circulating cells to produce other tissues in addition to blood The freemartin model allows one to analyse perfectly healthy and unmanipulated animals without resorting to transplantation often used in stem cell research Fictional use editIn the Aldous Huxley novel Brave New World a freemartin mentioned in chapters 1 3 11 and 17 is a woman who has been deliberately made sterile by exposure to hormones during fetal development in the book government policy requires freemartins to constitute 70 of the female population A side effect of this is some freemartin women having developed beards The Robert A Heinlein novel Beyond This Horizon lists the clever and repulsively beautiful pseudo feminine freemartins as one of the genetically engineered specialist types of humans that were created in the Empire of the Great Khans chapter 2 In the Robert Heinlein novel Farnham s Freehold the protagonist Hugh Farnham is given a companion bedwarmer that is described as a natural freemartin In the Avram Davidson story The House the Blakeneys Built the cattle are freemartins In the fantasy book series Bazil Broketail by Christopher Rowley freemartin is the name for a breed of sterile female dragons In Footfall by Larry Niven and Jerry Pournelle a lithely built human woman uses the term freemartin to describe herself while doubting her sexuality In Nicola Griffith s novel Hild the title character is sometimes referred to by others as a freemartin in reference to her non feminine character and social role In Lauren Groff s novel Matrix New York Riverhead Books 2021 12th century English peasants use freemartins to pull wagons References edit Freemartinism at the U S National Library of Medicine Medical Subject Headings MeSH Rota A Ballarin C Vigier B Cozzi B Rey R October 2002 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 129 1 39 44 doi 10 1016 S0016 6480 02 00514 2 PMID 12409094 a href Template Cite journal html title Template Cite journal cite journal a CS1 maint multiple names authors list link In utero cell transfer between porcine littermates in Reproduction Fertility and Development 2011 23 2 297 302 doi 10 1071 RD10165 9 Abnormalities of Development and Pregnancy Veterinary reproduction and obstetrics David E Noakes Timothy J Parkinson Gary C W England Tenth ed Edinburgh Scotland 2019 pp 168 194 doi 10 1016 B978 0 7020 7233 8 00009 4 ISBN 978 0 7020 7238 3 OCLC 1077474208 S2CID 81828645 a href Template Cite book html title Template Cite book cite book a CS1 maint location missing publisher link CS1 maint others link a b c EARLY RECOGNITION OF THE FREEMARTIN CONDITION IN HEIFERS TWINBORN WITH BULLS by W W Swett C A Matthews and R R Graves in the Journal of Agricultural Research vol 61 no 8 October 15 1940 Hunter John 1779 Account of the Free Martin By Mr John Hunter F R S Philosophical Transactions of the Royal Society of London 69 279 93 Bibcode 1779RSPT 69 279H doi 10 1098 rstl 1779 0020 JSTOR 106420 Nelson Randy An introduction to behavioral endocrinology Sinauer Associates Massachusetts 2005 pg 145 Keller K and Tandler J Wiener Tieraztl Wochensch 3 513 526 1916 verification needed Lillie FR April 1916 The Theory of the Free Martin Science 43 1113 611 3 Bibcode 1916Sci 43 611L doi 10 1126 science 43 1113 611 JSTOR 1641047 PMID 17756274 Freeman G March 2007 Explaining the freemartin Tandler and Keller vs Lillie and the question of priority Journal of Experimental Zoology B 308 2 105 12 doi 10 1002 jez b 21151 PMID 17219370 Cuthbert Bede 1859 1860 The folk lore of a country parish Once a Week 1 Vol 2 Bradbury amp Evans If twins are born in our country parish it is believed that of the little bipeds like the quadrupedal martin heifers and free martins only one will prove the father or mother of a family Padula AM June 2005 The freemartin syndrome an update Animal Reproduction Science 87 1 2 93 109 doi 10 1016 j anireprosci 2004 09 008 PMID 15885443 Eldridge FE Blazak WF March 1977 Chromosomal analysis of fertile female heterosexual twins in cattle Journal of Dairy Science 60 3 458 63 doi 10 3168 jds S0022 0302 77 83888 5 PMID 845292 Wilkes PR Munro IB Wijeratne WV February 1978 Studies on a sheep freemartin The Veterinary Record 102 7 140 2 doi 10 1136 vr 102 7 140 PMID 565559 S2CID 43776725 a href Template Cite journal html title Template Cite journal cite journal a CS1 maint multiple names authors list link Ilbery PL Williams D 1967 Evidence of the freemartin condition in the goat Cytogenetics 6 3 276 85 doi 10 1159 000129948 PMID 6035567 Bruere AN Fielden ED Hutchings H March 1968 XX XY mosaicism in lymphocyte cultures from a pig with freemartin characteristics New Zealand Veterinary Journal 16 3 31 8 doi 10 1080 00480169 1968 33743 PMID 5241942 a href Template Cite journal html title Template Cite journal cite journal a CS1 maint multiple names authors list link Niku M Ilmonen L Pessa Morikawa T Iivanainen A 2004 Limited contribution of circulating cells to the development and maintenance of nonhematopoietic bovine tissues Stem Cells 22 1 12 20 doi 10 1634 stemcells 22 1 12 PMID 14688387 S2CID 13556114 a href Template Cite journal html title Template Cite journal cite journal a CS1 maint multiple names authors list link External links editMosaicism and Chimerism at colostate edu Archived 2006 03 30 at the Wayback Machine Picture at agric gov ab ca Archived 2019 02 24 at the Wayback Machine Retrieved from https en wikipedia org w index php title Freemartin amp oldid 1182159550, wikipedia, wiki, book, books, library,
