<?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>2007-9028</journal-id>
<journal-title><![CDATA[Ecosistemas y recursos agropecuarios]]></journal-title>
<abbrev-journal-title><![CDATA[Ecosistemas y recur. agropecuarios]]></abbrev-journal-title>
<issn>2007-9028</issn>
<publisher>
<publisher-name><![CDATA[Universidad Juárez Autónoma de Tabasco, Dirección de Investigación y Posgrado]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2007-90282018000200335</article-id>
<article-id pub-id-type="doi">10.19136/era.a5nl4.1524</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Characterization of the lactation curve of f1 Holstein-Zebu cows]]></article-title>
<article-title xml:lang="es"><![CDATA[Caracterización de la curva de lactancia de vacas f1 Holstein-Cebú]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Castillo Gallegos]]></surname>
<given-names><![CDATA[Epigmenio]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Nacional Autónoma de México Facultad de Medicina Veterinaria y Zootecnia Centro de Enseñanza, Investigación y Extensión en Ganadería Tropical]]></institution>
<addr-line><![CDATA[Martínez de la Torre Veracruz]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>04</month>
<year>2018</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>04</month>
<year>2018</year>
</pub-date>
<volume>5</volume>
<numero>14</numero>
<fpage>335</fpage>
<lpage>343</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S2007-90282018000200335&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S2007-90282018000200335&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S2007-90282018000200335&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[ABSTRACT: The objective was to find a function to describe the lactation curve of grazing Holstein - Zebu cows (n=23) in tropical México. Twelve were based on the general nonlinear function A* &#981; 1(x)* &#981; 2(x): A, a positive scalar; &#981; 1, a positive monotonically increasing function with asymptote &#981; 1 = 1 ; &#981; 2, is a monotonically decreasing function with asymptote &#981; 2 = 0 and initial value of 1; and x is lactation time (days). For &#981; 1, the Mitscherlitsch, Michaelis-Menten, generalized saturation kinetics, logistic, Gompertz and hyperbolic tangent equations were used, whilst for &#981; 2, they were the exponential and inverse linear. A gamma function, the more used, and the addition of two logistic equations, the more biologically explicit, were also included. The smaller value of the Akaike information criterion corrected (AIC c ) indicated the latter was the one with the best fit, so its use to study factors affecting the lactation curve is suggested.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[RESUMEN: El objetivo fue encontrar una función para describir la curva de lactancia de vacas Holstein - Cebú (n = 23) en pastoreo en el trópico mexicano. Doce se basaron en la función general no lineal A* &#981; 1(x)* &#981; 2(x): A, escalar positivo; &#981; 1 función de crecimiento monótona con asíntota &#981; 1 = 1 ; &#981; 2, función de decremento monótono con asíntota &#981; 2 = 0 y valor inicial de 1; x, días de lactancia. Para &#981; 1, se emplearon las ecuaciones de Mitscherlitsch, Michaelis-Menten, cinética de saturación generalizada, logística, Gompertz y tangente hiperbólica, y para &#981; 2 estas fueron exponencial y lineal inversa. También se incluyeron una función gama, la más utilizada, y la adición de dos logísticas, la más explícita biológicamente. Esta última se consideró como la de mejor ajuste porque tuvo el menor valor del criterio de información de Akaike (AIC c ), por lo que se sugiere su uso para estudiar factores que afectan la curva de lactancia.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Tropics]]></kwd>
<kwd lng="en"><![CDATA[dual-purpose]]></kwd>
<kwd lng="en"><![CDATA[grazing]]></kwd>
<kwd lng="en"><![CDATA[milk yield]]></kwd>
<kwd lng="en"><![CDATA[nonlinear functions]]></kwd>
<kwd lng="es"><![CDATA[Trópico]]></kwd>
<kwd lng="es"><![CDATA[doble propósito]]></kwd>
<kwd lng="es"><![CDATA[pastoreo]]></kwd>
<kwd lng="es"><![CDATA[rendimiento de leche]]></kwd>
<kwd lng="es"><![CDATA[funciones no lineales]]></kwd>
</kwd-group>
</article-meta>
</front><back>
<ref-list>
<ref id="B1">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Brody]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
<name>
<surname><![CDATA[Ragsdale]]></surname>
<given-names><![CDATA[AC]]></given-names>
</name>
<name>
<surname><![CDATA[Turner]]></surname>
<given-names><![CDATA[CW]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The rate of decline of milk secretion with the advance of the period of lactation]]></article-title>
<source><![CDATA[Journal of General Physiology]]></source>
<year>1923</year>
<volume>5</volume>
<page-range>441-4</page-range></nlm-citation>
</ref>
<ref id="B2">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Brody]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
<name>
<surname><![CDATA[Turner]]></surname>
<given-names><![CDATA[CW]]></given-names>
</name>
<name>
<surname><![CDATA[Ragsdale]]></surname>
<given-names><![CDATA[AC]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The relation between the initial rise and the subsequent decline of milk secretion following parturition]]></article-title>
<source><![CDATA[Journal of General Physiology]]></source>
<year>1924</year>
<volume>6</volume>
<page-range>541-5</page-range></nlm-citation>
</ref>
<ref id="B3">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Cobby]]></surname>
<given-names><![CDATA[JM]]></given-names>
</name>
<name>
<surname><![CDATA[Le Du]]></surname>
<given-names><![CDATA[YLP]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[On fitting curves to lactation data]]></article-title>
<source><![CDATA[Animal Production]]></source>
<year>1978</year>
<volume>26</volume>
<page-range>127-33</page-range></nlm-citation>
</ref>
<ref id="B4">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Dijkstra]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[France]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[Dhanoa]]></surname>
<given-names><![CDATA[MS]]></given-names>
</name>
<name>
<surname><![CDATA[Maas]]></surname>
<given-names><![CDATA[JA]]></given-names>
</name>
<name>
<surname><![CDATA[Hanigan]]></surname>
<given-names><![CDATA[MD]]></given-names>
</name>
<name>
<surname><![CDATA[Rook]]></surname>
<given-names><![CDATA[AJ]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[A model to describe growth patterns of the mammary gland during pregnancy and lactation]]></article-title>
<source><![CDATA[Journal of Dairy Science]]></source>
<year>1997</year>
<volume>80</volume>
<page-range>2340-54</page-range></nlm-citation>
</ref>
<ref id="B5">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Galaviz-Rodríguez]]></surname>
<given-names><![CDATA[JR]]></given-names>
</name>
<name>
<surname><![CDATA[Vázquez-Peláez]]></surname>
<given-names><![CDATA[CG]]></given-names>
</name>
<name>
<surname><![CDATA[Ruiz-Lopez]]></surname>
<given-names><![CDATA[FJ]]></given-names>
</name>
<name>
<surname><![CDATA[Lagunes-Lagunes]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[Calderón-Robles]]></surname>
<given-names><![CDATA[R]]></given-names>
</name>
<name>
<surname><![CDATA[Rosete-Hernández]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Factores ambientales que afectan la curva de lactancia en vacas Suizo Pardo en clima subtropical]]></article-title>
<source><![CDATA[Técnica Pecuaria en México]]></source>
<year>1998</year>
<volume>36</volume>
<page-range>163-71</page-range></nlm-citation>
</ref>
<ref id="B6">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Knight]]></surname>
<given-names><![CDATA[HC]]></given-names>
</name>
<name>
<surname><![CDATA[Wilde]]></surname>
<given-names><![CDATA[CJ]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Mammary cell changes during pregnancy and lactation]]></article-title>
<source><![CDATA[Livestock Production Science]]></source>
<year>1993</year>
<volume>35</volume>
<page-range>3-19</page-range></nlm-citation>
</ref>
<ref id="B7">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Knight]]></surname>
<given-names><![CDATA[HC]]></given-names>
</name>
<name>
<surname><![CDATA[Peaker]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<name>
<surname><![CDATA[Wilde]]></surname>
<given-names><![CDATA[CJ]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Local control of mammary development and function]]></article-title>
<source><![CDATA[Reviews of Reproduction]]></source>
<year>1998</year>
<volume>3</volume>
<page-range>104-12</page-range></nlm-citation>
</ref>
<ref id="B8">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Motulsky]]></surname>
<given-names><![CDATA[H]]></given-names>
</name>
<name>
<surname><![CDATA[Christopolous]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
</person-group>
<source><![CDATA[Fitting Models to Biological Data Using Linear and Nonlinear Regression: A Practical Guide to Curve Fitting]]></source>
<year>2003</year>
<edition>Second</edition>
<publisher-loc><![CDATA[San Diego CA USA ]]></publisher-loc>
<publisher-name><![CDATA[GraphaPad Software Inc]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B9">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Neal]]></surname>
<given-names><![CDATA[HDSC]]></given-names>
</name>
<name>
<surname><![CDATA[Thomley]]></surname>
<given-names><![CDATA[JHM]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The lactation curve in cattle: a mathematical model of the mammary gland]]></article-title>
<source><![CDATA[The Journal of Agricultural Science]]></source>
<year>1983</year>
<volume>101</volume>
<page-range>389-400</page-range></nlm-citation>
</ref>
<ref id="B10">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Osorio-Arce]]></surname>
<given-names><![CDATA[MM]]></given-names>
</name>
<name>
<surname><![CDATA[Segura-Correa]]></surname>
<given-names><![CDATA[JC]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Factores que afectan la curva de lactancia de vacas Bos taurus x Bos indicus en un sistema de doble propósito en el trópico húmedo de Tabasco, México]]></article-title>
<source><![CDATA[Técnica Pecuaria en México]]></source>
<year>2005</year>
<volume>43</volume>
<page-range>127-37</page-range></nlm-citation>
</ref>
<ref id="B11">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Papajcsik]]></surname>
<given-names><![CDATA[IA]]></given-names>
</name>
<name>
<surname><![CDATA[Bodero]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Modelling lactation curves of Friesian cows in a subtropical climate]]></article-title>
<source><![CDATA[Animal Science]]></source>
<year>1988</year>
<volume>47</volume>
<page-range>201-7</page-range></nlm-citation>
</ref>
<ref id="B12">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Pollot]]></surname>
<given-names><![CDATA[G]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[A biological approach to lactation curve analysis for milk yield]]></article-title>
<source><![CDATA[Journal of Dairy Science]]></source>
<year>2000</year>
<volume>83</volume>
<page-range>2448-58</page-range></nlm-citation>
</ref>
<ref id="B13">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Pollot]]></surname>
<given-names><![CDATA[GE]]></given-names>
</name>
<name>
<surname><![CDATA[Gootwine]]></surname>
<given-names><![CDATA[E]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Appropriate mathematical models for describing the complete lactation of dairy sheep]]></article-title>
<source><![CDATA[Animal Science]]></source>
<year>2000</year>
<volume>71</volume>
<page-range>197-207</page-range></nlm-citation>
</ref>
<ref id="B14">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Rook]]></surname>
<given-names><![CDATA[AJ]]></given-names>
</name>
<name>
<surname><![CDATA[France]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[Dhanoa]]></surname>
<given-names><![CDATA[MS]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[On the mathematical description of lactation curves]]></article-title>
<source><![CDATA[Journal of Agricultural Science]]></source>
<year>1993</year>
<volume>121</volume>
<page-range>97-102</page-range></nlm-citation>
</ref>
<ref id="B15">
<nlm-citation citation-type="book">
<collab>SAS</collab>
<article-title xml:lang=""><![CDATA[Proc Mixed]]></article-title>
<source><![CDATA[SAS/STAT® 9.22 User's Guide]]></source>
<year>2010</year>
<page-range>4514-718</page-range><publisher-loc><![CDATA[Cary, NC ]]></publisher-loc>
<publisher-name><![CDATA[SAS Institute Inc]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B16">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Silvert]]></surname>
<given-names><![CDATA[W]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Practical curve fitting]]></article-title>
<source><![CDATA[Limnology and Oceanography]]></source>
<year>1979</year>
<volume>24</volume>
<page-range>767-73</page-range></nlm-citation>
</ref>
<ref id="B17">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Val-Arreola]]></surname>
<given-names><![CDATA[D]]></given-names>
</name>
<name>
<surname><![CDATA[Kebreab]]></surname>
<given-names><![CDATA[E]]></given-names>
</name>
<name>
<surname><![CDATA[Dijkstra]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[France]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Study of the lactation curve in dairy cattle on farms in central Mexico]]></article-title>
<source><![CDATA[Journal of Dairy Science]]></source>
<year>2004</year>
<volume>87</volume>
<page-range>3789-99</page-range></nlm-citation>
</ref>
<ref id="B18">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Vinay-Vadillo]]></surname>
<given-names><![CDATA[JC]]></given-names>
</name>
<name>
<surname><![CDATA[Villagómez-Cortés]]></surname>
<given-names><![CDATA[JA]]></given-names>
</name>
<name>
<surname><![CDATA[Acosta-Rodríguez]]></surname>
<given-names><![CDATA[MR]]></given-names>
</name>
<name>
<surname><![CDATA[Rocher]]></surname>
<given-names><![CDATA[C]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Shapes of lactation curves of F1 (Holstein X Zebu) cows in the humid tropic of Veracruz, México]]></article-title>
<source><![CDATA[International Journal of Animal and Veterinary Advances]]></source>
<year>2012</year>
<volume>4</volume>
<page-range>370-7</page-range></nlm-citation>
</ref>
<ref id="B19">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Wilde]]></surname>
<given-names><![CDATA[CJ]]></given-names>
</name>
<name>
<surname><![CDATA[Quarrie]]></surname>
<given-names><![CDATA[LH]]></given-names>
</name>
<name>
<surname><![CDATA[Tonner]]></surname>
<given-names><![CDATA[E]]></given-names>
</name>
<name>
<surname><![CDATA[Flint]]></surname>
<given-names><![CDATA[DJ]]></given-names>
</name>
<name>
<surname><![CDATA[Peaker]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Mammary apoptosis]]></article-title>
<source><![CDATA[Livestock Production Science]]></source>
<year>1997</year>
<volume>50</volume>
<page-range>29-37</page-range></nlm-citation>
</ref>
<ref id="B20">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Wood]]></surname>
<given-names><![CDATA[PDP]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Algebraic model of the lactation curve in cattle]]></article-title>
<source><![CDATA[Nature]]></source>
<year>1967</year>
<volume>216</volume>
<page-range>164-5</page-range></nlm-citation>
</ref>
<ref id="B21">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Wood]]></surname>
<given-names><![CDATA[PDP]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The biometry of lactation]]></article-title>
<source><![CDATA[The Journal of Agricultural Science]]></source>
<year>1977</year>
<volume>88</volume>
<page-range>333-9</page-range></nlm-citation>
</ref>
</ref-list>
</back>
</article>
