<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>1659-4266</journal-id>
<journal-title><![CDATA[Cuadernos de Investigación UNED]]></journal-title>
<abbrev-journal-title><![CDATA[Cuadernos de Investigación UNED]]></abbrev-journal-title>
<issn>1659-4266</issn>
<publisher>
<publisher-name><![CDATA[Universidad Estatal a Distancia de Costa Rica]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1659-42662018000200416</article-id>
<article-id pub-id-type="doi">10.22458/urj.v10i2.2170</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Tiempo y dosis óptimas de fluoximesterona, para masculinización de crías del pez maya Cichlasoma urophthalmus (Percidae: Cichlidae)]]></article-title>
<article-title xml:lang="en"><![CDATA[Optimal time and dose of fluoxymesterone, for masculinization of Mayan fish Cichlasoma urophthalmus (Percidae: Cichlidae)]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Gutiérrez-Sigueros]]></surname>
<given-names><![CDATA[Irma]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Cuenca-Soria]]></surname>
<given-names><![CDATA[Carlos A.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Navarro-Angulo]]></surname>
<given-names><![CDATA[Leonardo I.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Maldonado-Enríquez]]></surname>
<given-names><![CDATA[Emilio J.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Melgar-Valdes]]></surname>
<given-names><![CDATA[Carolina E.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Castillo-Domínguez]]></surname>
<given-names><![CDATA[Alfonso]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Juárez Autónoma de Tabasco  ]]></institution>
<addr-line><![CDATA[Tenosique Tabasco]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2018</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2018</year>
</pub-date>
<volume>10</volume>
<numero>2</numero>
<fpage>416</fpage>
<lpage>421</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_arttext&amp;pid=S1659-42662018000200416&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_abstract&amp;pid=S1659-42662018000200416&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_pdf&amp;pid=S1659-42662018000200416&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen La masculinización en peces cíclidos, es de importancia capital para fines de mejora en la producción piscícola. El objeto de la presente investigación fue obtener la dosis y tiempo óptimos de exposición a la hormona fluoximesterona (FM), durante la masculinización del cíclido Maya Cichlasoma urophthalmus. Así, se probaron, dos tiempos de exposición (45 y 60 días) y cuatro dosis de andrógeno (0, 15, 30 y 60mg/kg de alimento), de manera que se tuvieron cinco tratamientos (15mg 60d, 30mg 45d, 30mg 60d, 60mg 45d y 60mg 60d) y un grupo testigo sin hormona (0mg 60d, CTL), por triplicado. Un kilogramo de alimento iniciador para tilapia Purina (45% de proteína), fue rociado con solución hormonada previamente disuelta en alcohol etílico, a razón de las dosis de prueba antes mencionadas por separado. Se administró alimento hormonado a saciedad, a crías de C. urophthalmus (siete días después de la eclosión) según el tratamiento. Los resultados revelaron que la proporción promedio de machos (69,1±2,7%), obtenida con la dosis 60mg/kg de FM, suministrada vía alimento por 45 días (60mg 45d), fue significativamente mayor, al resto de los tratamientos probados (Tukey, p&lt;0,05, k = 6, N-k = 12). Tales resultados obligan a revisar nuevas técnicas para la administración de hormonas esteroides (bioencapsulación), que por un lado, disminuyan los problemas de reproducción precoz en el cultivo de esta especie nativa, y por otro, constituyan técnicas más amigables con el entorno ambiental, lo cual podría minimizar la carga residual de hormonas esteroides en los cuerpos acuáticos.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract The production of all-male populations in cichlid fish, is crucial to obtain high yielding in fish farming. The aim of this paper was to determinate the optimal dose and time of exposure to fluoxymesterone (FM), during the masculinization of Mayan cichlid Cichlasoma urophthalmus larvae. Therefore, two periods of exposure to FM (45 and 60 days) and four androgen doses (0, 15, 30 and 60mg/kg of food) were tested, having a total of five treatments with FM (15mg 60d, 30mg 45d, 30mg 60d, 60mg 45d and 60mg 60d) and one control group (0mg 60d, CTL), in triplicate. One kilogram of Purina tilapia starter feed (45% protein) was sprayed with a hormone solution previously dissolved in ethyl alcohol, according to each separate testing dose mentioned above. C. urophthalmus larvae were fed hormonal foods ad libitum (seven days after hatching) based on each treatment. Results revealed that male average rate (69,1±2,7%) obtained from the 60mg/kg of FM dose, administered with food for 45 days (60mg 45d) was significantly greater in comparison to the other tested treatments (Tukey, p&lt;0,05, k = 6, N-k = 12). Thus, it is necessary to review new techniques to administer steroid hormones (bioencapsulation) that, on one hand, reduce precocious reproduction problems in the cultivation of this species and, on the other hand, establish more environmentally friendly techniques, which could minimize the presence of steroid hormone waste on aquatic ecosystems.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Time]]></kwd>
<kwd lng="en"><![CDATA[dose]]></kwd>
<kwd lng="en"><![CDATA[fluoxymesterone]]></kwd>
<kwd lng="en"><![CDATA[masculinization]]></kwd>
<kwd lng="en"><![CDATA[Cichlasoma]]></kwd>
<kwd lng="en"><![CDATA[urophthalmus]]></kwd>
<kwd lng="es"><![CDATA[Tiempo]]></kwd>
<kwd lng="es"><![CDATA[dosis]]></kwd>
<kwd lng="es"><![CDATA[fluoximesterona]]></kwd>
<kwd lng="es"><![CDATA[masculinización]]></kwd>
<kwd lng="es"><![CDATA[Cichlasoma]]></kwd>
<kwd lng="es"><![CDATA[urophthalmus]]></kwd>
</kwd-group>
</article-meta>
</front><back>
<ref-list>
<ref id="B1">
<nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Alfonso]]></surname>
<given-names><![CDATA[L. O. B.]]></given-names>
</name>
<name>
<surname><![CDATA[Wassermann]]></surname>
<given-names><![CDATA[G. J]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Immersion in an aromatizable and non- aromatizable androgens induces high rates of masculinization in Nile Tilapia Oreochromis niloticus.]]></article-title>
<source><![CDATA[Aquaculture América]]></source>
<year>2002</year>
<page-range>2</page-range><publisher-loc><![CDATA[California USA ]]></publisher-loc>
</nlm-citation>
</ref>
<ref id="B2">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Contreras-Sánchez]]></surname>
<given-names><![CDATA[W. M.]]></given-names>
</name>
<name>
<surname><![CDATA[Márquez-Couturier]]></surname>
<given-names><![CDATA[G.]]></given-names>
</name>
<name>
<surname><![CDATA[Feist]]></surname>
<given-names><![CDATA[G. W.]]></given-names>
</name>
<name>
<surname><![CDATA[Hernández-Franyutti]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
<name>
<surname><![CDATA[Schreck]]></surname>
<given-names><![CDATA[C. B.]]></given-names>
</name>
<name>
<surname><![CDATA[Giannico]]></surname>
<given-names><![CDATA[G.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Aquacultural Practices by Incorporation of Native species and Implementation of Sex Invertion Techniques. (Technical Report).]]></article-title>
<source><![CDATA[Aquaculture]]></source>
<year>2003</year>
<volume>31</volume>
<page-range>189-95</page-range></nlm-citation>
</ref>
<ref id="B3">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Cuenca]]></surname>
<given-names><![CDATA[C. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Álvarez-González]]></surname>
<given-names><![CDATA[C. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Ortiz-Galindo]]></surname>
<given-names><![CDATA[J. L.]]></given-names>
</name>
<name>
<surname><![CDATA[Guerrero-Zárate]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
<name>
<surname><![CDATA[Perera-García]]></surname>
<given-names><![CDATA[M. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Hernández-Gómez]]></surname>
<given-names><![CDATA[R. E.]]></given-names>
</name>
<name>
<surname><![CDATA[Nolasco-Soria]]></surname>
<given-names><![CDATA[H.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Digestibilidad in vitro de ingredientes proteínicos en la mojarra castarrica Cichlasoma urophthalmus.]]></article-title>
<source><![CDATA[Ecosistemas y Recursos Agropecuarios]]></source>
<year>2013</year>
<volume>29</volume>
<numero>3</numero>
<issue>3</issue>
<page-range>263-75</page-range></nlm-citation>
</ref>
<ref id="B4">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Devlin]]></surname>
<given-names><![CDATA[R. H.]]></given-names>
</name>
<name>
<surname><![CDATA[Nagahama]]></surname>
<given-names><![CDATA[Y.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Sex determination and sex differentiation on fish: an overview genetic, physiological and environmental influences.]]></article-title>
<source><![CDATA[Aquaculture]]></source>
<year>2002</year>
<volume>208</volume>
<page-range>191-364</page-range></nlm-citation>
</ref>
<ref id="B5">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Green]]></surname>
<given-names><![CDATA[B. W.]]></given-names>
</name>
<name>
<surname><![CDATA[Veverica]]></surname>
<given-names><![CDATA[K. L.]]></given-names>
</name>
<name>
<surname><![CDATA[Fitzpatrick]]></surname>
<given-names><![CDATA[M. S.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Fry and fingerling production]]></article-title>
<person-group person-group-type="editor">
<name>
<surname><![CDATA[Hillary]]></surname>
<given-names><![CDATA[S.]]></given-names>
</name>
<name>
<surname><![CDATA[Egna]]></surname>
<given-names><![CDATA[Claude]]></given-names>
</name>
<name>
<surname><![CDATA[E.]]></surname>
<given-names><![CDATA[Boyd]]></given-names>
</name>
</person-group>
<source><![CDATA[Dynamics of Pond Aquacuture]]></source>
<year>1997</year>
<page-range>437</page-range><publisher-loc><![CDATA[New York, USA ]]></publisher-loc>
<publisher-name><![CDATA[CRC Press]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B6">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Hunter]]></surname>
<given-names><![CDATA[G. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Donaldson]]></surname>
<given-names><![CDATA[E. M.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Hormonal sex control and its application to fish aquaculture.]]></article-title>
<person-group person-group-type="editor">
<name>
<surname><![CDATA[W. S.]]></surname>
<given-names><![CDATA[Hoar.,]]></given-names>
</name>
<name>
<surname><![CDATA[D. J.]]></surname>
<given-names><![CDATA[Randall]]></given-names>
</name>
<name>
<surname><![CDATA[E.M.]]></surname>
<given-names><![CDATA[Donaldson]]></given-names>
</name>
</person-group>
<source><![CDATA[Fish physiology]]></source>
<year>1983</year>
<volume>IXB</volume>
<page-range>223-303</page-range><publisher-loc><![CDATA[New York/London ]]></publisher-loc>
<publisher-name><![CDATA[Academic press.]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B7">
<nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Hurtado]]></surname>
<given-names><![CDATA[T. N.]]></given-names>
</name>
</person-group>
<source><![CDATA[Inversión sexual en tilapias: revisión bibliográfica.]]></source>
<year>2005</year>
</nlm-citation>
</ref>
<ref id="B8">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Jiménez-Badillo]]></surname>
<given-names><![CDATA[M. L.]]></given-names>
</name>
<name>
<surname><![CDATA[Arredondo-Figueroa]]></surname>
<given-names><![CDATA[J. L.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Effect of oral treatment of synthetic androgens on sex ratio, survival and growth rates, in three strains of tilapia.]]></article-title>
<source><![CDATA[Hidrobiológica]]></source>
<year>2000</year>
<month>a</month>
<volume>10</volume>
<numero>2</numero>
<issue>2</issue>
<page-range>115-20</page-range></nlm-citation>
</ref>
<ref id="B9">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Jiménez]]></surname>
<given-names><![CDATA[B. M. L.]]></given-names>
</name>
<name>
<surname><![CDATA[Arredondo]]></surname>
<given-names><![CDATA[J. L]]></given-names>
</name>
</person-group>
<source><![CDATA[Manual técnico para la reversión sexual de tilapia.]]></source>
<year>2000</year>
<month>b</month>
<publisher-loc><![CDATA[Serie Desarrollo Tecnológicos en Acuacultura. México ]]></publisher-loc>
<publisher-name><![CDATA[Editorial de la Universidad Autónoma Metropolitana Unidad Iztapalapa.]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B10">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Khallaf]]></surname>
<given-names><![CDATA[E.]]></given-names>
</name>
<name>
<surname><![CDATA[Galal]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Athuman]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The biology of Oreochromis niloticus in a polluted canal.]]></article-title>
<source><![CDATA[Ecotoxicology]]></source>
<year>2003</year>
<volume>12</volume>
<page-range>405-16</page-range></nlm-citation>
</ref>
<ref id="B11">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Liñan-Cabello]]></surname>
<given-names><![CDATA[M. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Robles-Basto]]></surname>
<given-names><![CDATA[C. M.]]></given-names>
</name>
<name>
<surname><![CDATA[Mena-Herrera]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Somatic growth effects of intramuscular injection of growth hormone in androgen-treated juvenile Nile tilapia, Oreochromis niloticus (Perciformes: Cichlidae).]]></article-title>
<source><![CDATA[Revista de Biología Tropical]]></source>
<year>2012</year>
<volume>61</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>203-12</page-range></nlm-citation>
</ref>
<ref id="B12">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[López]]></surname>
<given-names><![CDATA[C. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Carvajal]]></surname>
<given-names><![CDATA[D. L.,]]></given-names>
</name>
<name>
<surname><![CDATA[Botero]]></surname>
<given-names><![CDATA[M. C.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Masculinización de tilapia roja Oreochromis niloticus por inmersión, utilizando 17 &#945;-metiltestosterona.]]></article-title>
<source><![CDATA[Revista Colombiana de Ciencias Pecuarias]]></source>
<year>2007</year>
<volume>20</volume>
<page-range>318-26</page-range></nlm-citation>
</ref>
<ref id="B13">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Marcillo]]></surname>
<given-names><![CDATA[G. E.]]></given-names>
</name>
<name>
<surname><![CDATA[Landivar]]></surname>
<given-names><![CDATA[Z. J.]]></given-names>
</name>
</person-group>
<source><![CDATA[Tecnología de producción de alevinos monosexo de tilapia]]></source>
<year>2000</year>
<publisher-loc><![CDATA[Ecuador ]]></publisher-loc>
<publisher-name><![CDATA[Editorial de la Escuela Superior Politécnica del Litoral.]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B14">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Martínez-Palacios]]></surname>
<given-names><![CDATA[C. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Ross.]]></surname>
<given-names><![CDATA[L. G]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The feeding ecology of the Central American cichlid Cichlasoma urophthalmus (Günther 1862).]]></article-title>
<source><![CDATA[Journal of Fish Biology]]></source>
<year>1988</year>
<volume>33</volume>
<page-range>665-70</page-range></nlm-citation>
</ref>
<ref id="B15">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Martínez-Palacios]]></surname>
<given-names><![CDATA[C. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Ross]]></surname>
<given-names><![CDATA[L. G.]]></given-names>
</name>
</person-group>
<source><![CDATA[Biología y cultivo de la mojarra latinoamericana Cichlasoma urophthalmus]]></source>
<year>1994</year>
<edition>1</edition>
<publisher-loc><![CDATA[CONACyT México ]]></publisher-loc>
<publisher-name><![CDATA[Grafos Editores S. A de C. V.]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B16">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Morales-Díaz]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
</person-group>
<source><![CDATA[La tilapia en México. Biología, cultivo y pesquerías]]></source>
<year>1991</year>
<publisher-loc><![CDATA[México ]]></publisher-loc>
<publisher-name><![CDATA[AGT Editor]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B17">
<nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Moreno]]></surname>
<given-names><![CDATA[E. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Rodríguez]]></surname>
<given-names><![CDATA[C. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Barriga]]></surname>
<given-names><![CDATA[S. I.]]></given-names>
</name>
<name>
<surname><![CDATA[Arredondo]]></surname>
<given-names><![CDATA[J. L.]]></given-names>
</name>
</person-group>
<source><![CDATA[Producción de Tilapia del Nilo (Oreochromis niloticus) masculinizada con la hormona fluoximesterona en sistemas de recirculación.]]></source>
<year>2003</year>
<page-range>77-88</page-range><publisher-loc><![CDATA[Zaragoza, España ]]></publisher-loc>
</nlm-citation>
</ref>
<ref id="B18">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Mossad]]></surname>
<given-names><![CDATA[M. N. M.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Biological studies on five fish species from Lake Qarun, Egypt, Length-weight relationship and condition factor]]></article-title>
<source><![CDATA[Journal of Zoological Society]]></source>
<year>1990</year>
<volume>21</volume>
<page-range>331-44</page-range></nlm-citation>
</ref>
<ref id="B19">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Nehemia]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
<name>
<surname><![CDATA[Maganira]]></surname>
<given-names><![CDATA[J. D.]]></given-names>
</name>
<name>
<surname><![CDATA[Rumisha]]></surname>
<given-names><![CDATA[C.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Length-Weight relationship and condition factor of tilapia species grown in marine and fresh water ponds.]]></article-title>
<source><![CDATA[Agriculture and Biology Journal of North America]]></source>
<year>2012</year>
<volume>3</volume>
<numero>3</numero>
<issue>3</issue>
<page-range>117-24</page-range></nlm-citation>
</ref>
<ref id="B20">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Pérez-Sánchez]]></surname>
<given-names><![CDATA[E.]]></given-names>
</name>
<name>
<surname><![CDATA[Páramo-Delgadillo]]></surname>
<given-names><![CDATA[S.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The culture of cichlids of the southeastern Mexico.]]></article-title>
<source><![CDATA[Aquaculture Research]]></source>
<year>2008</year>
<volume>39</volume>
<page-range>777-83</page-range></nlm-citation>
</ref>
<ref id="B21">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Popma]]></surname>
<given-names><![CDATA[T. J.]]></given-names>
</name>
<name>
<surname><![CDATA[Green]]></surname>
<given-names><![CDATA[W. B.]]></given-names>
</name>
</person-group>
<source><![CDATA[Aquaculture production manual: Sex reversal of tilapia in earthen ponds.]]></source>
<year>1990</year>
<publisher-loc><![CDATA[USA ]]></publisher-loc>
<publisher-name><![CDATA[International Center for aquaculture]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B22">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Salgado]]></surname>
<given-names><![CDATA[Z. H.]]></given-names>
</name>
<name>
<surname><![CDATA[Azpeitia]]></surname>
<given-names><![CDATA[H. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Marañón]]></surname>
<given-names><![CDATA[H. S.]]></given-names>
</name>
<name>
<surname><![CDATA[Maya]]></surname>
<given-names><![CDATA[P. E.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Efecto anabólico y androgénico del esteroide acetato de trembolona en el guppy Poecilia reticulata.]]></article-title>
<source><![CDATA[Veterinaria México]]></source>
<year>2008</year>
<volume>39</volume>
<numero>3</numero>
<issue>3</issue>
<page-range>269-79</page-range></nlm-citation>
</ref>
<ref id="B23">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Vidal-López]]></surname>
<given-names><![CDATA[J. M.,]]></given-names>
</name>
<name>
<surname><![CDATA[Álvarez-González,]]></surname>
<given-names><![CDATA[A.,]]></given-names>
</name>
<name>
<surname><![CDATA[Contreras-Sánchez,]]></surname>
<given-names><![CDATA[W. M.,]]></given-names>
</name>
<name>
<surname><![CDATA[Hernández-Vidal ,]]></surname>
<given-names><![CDATA[U.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Masculinización del cíclido nativo Tenhuayaca, Petenia splendida. (Günther, 1862), usando nauplios de Artemia como vehículo del esteroide 17-&#945; metiltestosterona.]]></article-title>
<source><![CDATA[Hidrobiológica]]></source>
<year>2009</year>
<volume>19</volume>
<numero>3</numero>
<issue>3</issue>
<page-range>211-6</page-range></nlm-citation>
</ref>
<ref id="B24">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Zar]]></surname>
<given-names><![CDATA[J. H.]]></given-names>
</name>
</person-group>
<source><![CDATA[Biostatistical Analysis.]]></source>
<year>1974</year>
<publisher-loc><![CDATA[New Jersey, USA ]]></publisher-loc>
<publisher-name><![CDATA[Prentice-Hall, Englewood Clifs]]></publisher-name>
</nlm-citation>
</ref>
</ref-list>
</back>
</article>
