<?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>1659-1321</journal-id>
<journal-title><![CDATA[Agronomía Mesoamericana]]></journal-title>
<abbrev-journal-title><![CDATA[Agron. Mesoam]]></abbrev-journal-title>
<issn>1659-1321</issn>
<publisher>
<publisher-name><![CDATA[Universidad de Costa Rica]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1659-13212017000200389</article-id>
<article-id pub-id-type="doi">10.15517/ma.v28i2.23561</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Consumo de materia seca en un sistema silvopastoril de Tithonia diversifolia en trópico alto]]></article-title>
<article-title xml:lang="en"><![CDATA[Dry matter intake in a silvopastoral system of T. diversifolia in high tropics]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Mejía-Díaz]]></surname>
<given-names><![CDATA[Estefanía]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Mahecha-Ledesma]]></surname>
<given-names><![CDATA[Liliana]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Angulo-Arizala]]></surname>
<given-names><![CDATA[Joaquín]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad de Antioquia Facultad de Ciencias Agrarias ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>CO</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad de Antioquia Facultad de Ciencias Agrarias ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>CO</country>
</aff>
<aff id="Af4">
<institution><![CDATA[,Universidad de Antioquia Facultad de Ciencias Agrarias ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>CO</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>08</month>
<year>2017</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>08</month>
<year>2017</year>
</pub-date>
<volume>28</volume>
<numero>2</numero>
<fpage>389</fpage>
<lpage>403</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_arttext&amp;pid=S1659-13212017000200389&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_abstract&amp;pid=S1659-13212017000200389&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_pdf&amp;pid=S1659-13212017000200389&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen El objetivo de este trabajo fue estimar el consumo de materia seca de forraje (CMSf) por vacas holstein bajo pastoreo. La investigación se llevó a cabo en el altiplano norte de Antioquia; se empleó un sistema silvopastoril con Tithonia diversifolia y Cenchrsus clandestinum (SSP) y un monocultivo de C. clandestinum . Se estimó el CMSf por diferentes metodologías y la relación de consumo kikuyo:botón de oro; también se determinó la intercambiabilidad de dos metodologías. Se llevaron a cabo dos ensayos, en el primero se utilizó el SSP sin ramoneo de botón de oro y el monocultivo; en el segundo se utilizaron los mismos sistemas con la diferencia que para el SSP los animales ramonearon la arbustiva. Se utilizaron doce vacas holstein lactantes aleatorizadas en los dos sistemas. El CMSf se estimó por los métodos indicadores (I), agronómico (A) y comportamiento al pastoreo (C), el método I fue el de referencia. En el Ensayo 1 se observó un mayor CMSf en el SSP, con un promedio de 14,7 kg/día (p&lt;0,05); en el Ensayo 2 no se evidenció diferencia en el CMSf, con un promedio de 13,3 kg/día (p&gt;0,005). La relación de consumo kikuyo:botón de oro fue de 95:5. El coeficiente de correlación de concordancia entre los métodos I y C cercano a 0 demostró que no son intercambiables. Los resultados sugieren que el SSP evaluado ofreció suficiente forraje para garantizar un óptimo CMSf.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract The aim of this study was to estimate the intake of dry matter forage (CMSf) by grazing holstein cows. The research was conducted in northern Antioquia highlands; a silvopastoral system with Tithonia diversifolia and Cenchrsus clandestinum (SSP) and a monoculture C. clandestinum were used. Were estimated the CMSf by different methodologies and kikuyu:wild sunflower consumption relation, also the interchangeability of two methodologies was determined. There were two conducted trials, in the first trail SSP was used without browsing of wild sunflower and monoculture; in the second trial the same system was applied, with the difference that for the SSP animals browsed the shrubby by themselves. Twelve random infant holstein cows were used in the two systems. CMSf was estimated by indicators (I), agronomic (A) and grazing behavior (C) methods, method I was the reference. In trial 1 more CMSf was observed in the SSP, with an average of 14.7 kg/day (p&lt;0.05); trial 2 showed no difference in the CMSf, with an average of 13.3 kg/day (p&gt;0.005). The kikuyu:wild sunflower consumption relation was 95:5. The correlation coefficient of concordance between the methods I and C near to 0 shown that they are not interchangeable. The results suggest that the SSP evaluated supplied sufficient forage to ensure optimal CMSf.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Cenchrus clandestinum]]></kwd>
<kwd lng="es"><![CDATA[hábitos alimentarios]]></kwd>
<kwd lng="es"><![CDATA[forraje]]></kwd>
<kwd lng="es"><![CDATA[sistemas de pastoreo]]></kwd>
<kwd lng="en"><![CDATA[Cenchrus clandestinum]]></kwd>
<kwd lng="en"><![CDATA[eating habits]]></kwd>
<kwd lng="en"><![CDATA[forage]]></kwd>
<kwd lng="en"><![CDATA[grazing systems]]></kwd>
</kwd-group>
</article-meta>
</front><back>
<ref-list>
<ref id="B1">
<nlm-citation citation-type="book">
<collab>AOAC (Association of Official Analysis Chemistry)</collab>
<source><![CDATA[AOAC: Official methods of analysis]]></source>
<year>2005</year>
<edition>18</edition>
<publisher-loc><![CDATA[MD, USA ]]></publisher-loc>
<publisher-name><![CDATA[AOAC]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B2">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Respuesta del pasto kikuyo ( Pennisetum clandestinum , Hoechst) a diferentes niveles de fertilización nitrogenada orgánica y/o mineral]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Apráez]]></surname>
<given-names><![CDATA[J.E.]]></given-names>
</name>
<name>
<surname><![CDATA[Benavides]]></surname>
<given-names><![CDATA[O.F.]]></given-names>
</name>
<name>
<surname><![CDATA[Tarapuez]]></surname>
<given-names><![CDATA[I.]]></given-names>
</name>
</person-group>
<source><![CDATA[Rev. Cienc. Agríc]]></source>
<year>1999</year>
<volume>16</volume>
<page-range>38-55</page-range></nlm-citation>
</ref>
<ref id="B3">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Invited review: Production and digestion of supplemented dairy cows on pasture]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Bargo]]></surname>
<given-names><![CDATA[F.]]></given-names>
</name>
<name>
<surname><![CDATA[Muller]]></surname>
<given-names><![CDATA[L.D.]]></given-names>
</name>
<name>
<surname><![CDATA[Kolver]]></surname>
<given-names><![CDATA[E.S.]]></given-names>
</name>
<name>
<surname><![CDATA[Delahoy]]></surname>
<given-names><![CDATA[J.E.]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Dairy Sci.]]></source>
<year>2003</year>
<volume>86</volume>
<page-range>1-42</page-range></nlm-citation>
</ref>
<ref id="B4">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Betancur]]></surname>
<given-names><![CDATA[J.F.]]></given-names>
</name>
<name>
<surname><![CDATA[Trujillo]]></surname>
<given-names><![CDATA[L.G.]]></given-names>
</name>
</person-group>
<source><![CDATA[Balance de nitrógeno en vacas lecheras de alta producción alimentadas con pasto kikuyo (Pennisetum clandestinum) y dos niveles de suplementación de proteína no degradable en el rumen]]></source>
<year>2004</year>
<publisher-loc><![CDATA[Medellín, COL ]]></publisher-loc>
<publisher-name><![CDATA[Universidad Nacional de Colombia]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B5">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Statistical methods for assessing agreement between two methods of clinical measurement]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Bland]]></surname>
<given-names><![CDATA[J.M.]]></given-names>
</name>
<name>
<surname><![CDATA[Altman]]></surname>
<given-names><![CDATA[D.G.]]></given-names>
</name>
</person-group>
<source><![CDATA[Lancet]]></source>
<year>1986</year>
<volume>1</volume>
<page-range>307-10</page-range></nlm-citation>
</ref>
<ref id="B6">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Efecto de la fertilización orgánica e inorgánica sobre variables agroproductivas y composición química del pasto estrella ( Cynodon nlemfuensis )]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Borges]]></surname>
<given-names><![CDATA[J.A.]]></given-names>
</name>
<name>
<surname><![CDATA[Barrios]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Escalona]]></surname>
<given-names><![CDATA[O.]]></given-names>
</name>
</person-group>
<source><![CDATA[Zootec. Trop.]]></source>
<year>2012</year>
<volume>30</volume>
<page-range>17-25</page-range></nlm-citation>
</ref>
<ref id="B7">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Carulla]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<name>
<surname><![CDATA[Cárdenas]]></surname>
<given-names><![CDATA[E.A.]]></given-names>
</name>
<name>
<surname><![CDATA[Sánchez]]></surname>
<given-names><![CDATA[N.]]></given-names>
</name>
<name>
<surname><![CDATA[Riveros]]></surname>
<given-names><![CDATA[C.]]></given-names>
</name>
</person-group>
<source><![CDATA[Valor nutricional de los forrajes más usados en los sistemas de producción lechera especializada de la Zona Andina Colombiana]]></source>
<year>2011</year>
<publisher-loc><![CDATA[COL. ]]></publisher-loc>
<publisher-name><![CDATA[Universidad Nacional de Colombia]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B8">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Castillo]]></surname>
<given-names><![CDATA[E.]]></given-names>
</name>
</person-group>
<source><![CDATA[Comportamiento ingestivo en ganado bovino de doble propósito]]></source>
<year>2007</year>
<publisher-loc><![CDATA[MEX ]]></publisher-loc>
<publisher-name><![CDATA[UNAM]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B9">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[A note on the use of chromium sesquioxide as a marker in nutritional experiments with dairy cows]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Chamberlain]]></surname>
<given-names><![CDATA[D.G.]]></given-names>
</name>
<name>
<surname><![CDATA[Thomas]]></surname>
<given-names><![CDATA[P.C.]]></given-names>
</name>
</person-group>
<source><![CDATA[Anim. Sci]]></source>
<year>1983</year>
<volume>36</volume>
<page-range>155-7</page-range></nlm-citation>
</ref>
<ref id="B10">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Forage intake by grazing livestock: A review]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Cordova]]></surname>
<given-names><![CDATA[F.J.]]></given-names>
</name>
<name>
<surname><![CDATA[Wallace]]></surname>
<given-names><![CDATA[J.D.]]></given-names>
</name>
<name>
<surname><![CDATA[Piepe]]></surname>
<given-names><![CDATA[R.D.]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Range Manag.]]></source>
<year>1978</year>
<volume>31</volume>
<page-range>430-8</page-range></nlm-citation>
</ref>
<ref id="B11">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Producción de leche con base en pasturas: el caso de los hatos especializados en Colombia]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Correa]]></surname>
<given-names><![CDATA[H.]]></given-names>
</name>
</person-group>
<source><![CDATA[Rev. Fac. Nal. Agron.]]></source>
<year>2009</year>
<volume>62</volume>
<page-range>1-5</page-range></nlm-citation>
</ref>
<ref id="B12">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Correa]]></surname>
<given-names><![CDATA[H.]]></given-names>
</name>
<name>
<surname><![CDATA[Pabón]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Carulla]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
</person-group>
<source><![CDATA[Efecto del manejo del pastoreo y la suplementación alimenticia en vacas lactantes de sistemas especializados sobre su metabolismo energético y proteico y el contenido de proteína en la leche]]></source>
<year>2009</year>
<publisher-loc><![CDATA[COL ]]></publisher-loc>
<publisher-name><![CDATA[Universidad Nacional de Colombia]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B13">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[La fibra en la alimentación del ganado lecher]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Cruz]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Sánchez]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
</person-group>
<source><![CDATA[Nutrición Animal Tropical]]></source>
<year>2000</year>
<volume>6</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>39-74</page-range></nlm-citation>
</ref>
<ref id="B14">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Estimación del consumo de pasto estrella ( Cynodon plectostachyus K. Schum.) por vacas lecheras en pastoreo, mediante las técnicas de n-alcanos, diferencia en masa forrajera y comportamiento al pastoreo]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Estrada]]></surname>
<given-names><![CDATA[I.]]></given-names>
</name>
<name>
<surname><![CDATA[Avilés]]></surname>
<given-names><![CDATA[F.]]></given-names>
</name>
<name>
<surname><![CDATA[Estrada]]></surname>
<given-names><![CDATA[J.G.]]></given-names>
</name>
<name>
<surname><![CDATA[Pedraza]]></surname>
<given-names><![CDATA[P.E.]]></given-names>
</name>
<name>
<surname><![CDATA[Yong]]></surname>
<given-names><![CDATA[G.]]></given-names>
</name>
<name>
<surname><![CDATA[Castelán]]></surname>
<given-names><![CDATA[O.A.]]></given-names>
</name>
</person-group>
<source><![CDATA[Trop. Subtrop. Agroecosyst.]]></source>
<year>2014</year>
<volume>17</volume>
<page-range>463-77</page-range></nlm-citation>
</ref>
<ref id="B15">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Óxido de cromo e n-alcanos na estimativa do consumo de forragem de vacas em lactação em condições de pastejo]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Frota]]></surname>
<given-names><![CDATA[M.J.]]></given-names>
</name>
<name>
<surname><![CDATA[Coelho]]></surname>
<given-names><![CDATA[J.F.]]></given-names>
</name>
<name>
<surname><![CDATA[Magalhães]]></surname>
<given-names><![CDATA[L.]]></given-names>
</name>
<name>
<surname><![CDATA[Ferraz]]></surname>
<given-names><![CDATA[F.C.]]></given-names>
</name>
<name>
<surname><![CDATA[Wyllie]]></surname>
<given-names><![CDATA[A.C.]]></given-names>
</name>
<name>
<surname><![CDATA[Detman]]></surname>
<given-names><![CDATA[E.]]></given-names>
</name>
</person-group>
<source><![CDATA[R. Bras. Zootec.]]></source>
<year>2006</year>
<volume>35</volume>
<page-range>1535-42</page-range></nlm-citation>
</ref>
<ref id="B16">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Consumo y digestibilidad en novillos cebuínos en un sistema silvopastoril]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Gaviria]]></surname>
<given-names><![CDATA[X.]]></given-names>
</name>
<name>
<surname><![CDATA[Naranjo]]></surname>
<given-names><![CDATA[J.F.]]></given-names>
</name>
<name>
<surname><![CDATA[Bolívar]]></surname>
<given-names><![CDATA[D.M.]]></given-names>
</name>
<name>
<surname><![CDATA[Barahona]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
</person-group>
<source><![CDATA[Arch. Zootec.]]></source>
<year>2015</year>
<volume>64</volume>
<page-range>21-7</page-range></nlm-citation>
</ref>
<ref id="B17">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[The approximation of cattle diet through herbage sampling]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Halls]]></surname>
<given-names><![CDATA[L.K.]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Range Manag.]]></source>
<year>1954</year>
<volume>7</volume>
<page-range>269-70</page-range></nlm-citation>
</ref>
<ref id="B18">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[The comparative yield method for estimating dry matter yield of pasture]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Haydock]]></surname>
<given-names><![CDATA[K.P.]]></given-names>
</name>
<name>
<surname><![CDATA[Shaw]]></surname>
<given-names><![CDATA[N.H.]]></given-names>
</name>
</person-group>
<source><![CDATA[Aust. J. Exp. Agric. Anim. Husb.]]></source>
<year>1975</year>
<volume>15</volume>
<page-range>663-70</page-range></nlm-citation>
</ref>
<ref id="B19">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[The life zone system]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Holdrige]]></surname>
<given-names><![CDATA[L.R.]]></given-names>
</name>
</person-group>
<source><![CDATA[Adansonia]]></source>
<year>1966</year>
<volume>6</volume>
<numero>2</numero>
<issue>2</issue>
<page-range>199-203</page-range></nlm-citation>
</ref>
<ref id="B20">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[A concordance correlation coefficient to evaluate reproducibility]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Lin]]></surname>
<given-names><![CDATA[L.]]></given-names>
</name>
</person-group>
<source><![CDATA[Biometrics]]></source>
<year>1989</year>
<volume>45</volume>
<page-range>255-68</page-range></nlm-citation>
</ref>
<ref id="B21">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Efecto de la bovinaza en la composición nutricional del tubérculo de remolacha forrajera ( Beta vulgaris ) en el municipio de Pasto, departamento de Nariño]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Lafaux]]></surname>
<given-names><![CDATA[M.P.]]></given-names>
</name>
<name>
<surname><![CDATA[Bastidas]]></surname>
<given-names><![CDATA[J.A.]]></given-names>
</name>
<name>
<surname><![CDATA[Insuasty]]></surname>
<given-names><![CDATA[E.]]></given-names>
</name>
</person-group>
<source><![CDATA[Rev. Cienc. Anim.]]></source>
<year>2015</year>
<volume>9</volume>
<page-range>209-21</page-range></nlm-citation>
</ref>
<ref id="B22">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Análisis de la relación planta-animal desde el punto de vista nutricional en un sistema silvopastoril de Cynodon plectostachyus, Leucaena leucocephala y Prosopis juliflora en el Valle del Cauca]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Mahecha]]></surname>
<given-names><![CDATA[L.]]></given-names>
</name>
<name>
<surname><![CDATA[Durán]]></surname>
<given-names><![CDATA[C.V.]]></given-names>
</name>
<name>
<surname><![CDATA[Rosales]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
</person-group>
<source><![CDATA[Acta Agron.]]></source>
<year>2000</year>
<volume>50</volume>
<page-range>59-70</page-range></nlm-citation>
</ref>
<ref id="B23">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Tithonia diversifolia (hemsl.) Gray (botón de oro) como suplemento forrajero de vacas F1 (Holstein por Cebú)]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Mahecha]]></surname>
<given-names><![CDATA[L.]]></given-names>
</name>
<name>
<surname><![CDATA[Escobar]]></surname>
<given-names><![CDATA[J.P.]]></given-names>
</name>
<name>
<surname><![CDATA[Suárez]]></surname>
<given-names><![CDATA[J.F.]]></given-names>
</name>
<name>
<surname><![CDATA[Restrepo]]></surname>
<given-names><![CDATA[L.F.]]></given-names>
</name>
</person-group>
<source><![CDATA[Liv. Res. Rural Dev.]]></source>
<year>2007</year>
<volume>19</volume>
<numero>2</numero>
<issue>2</issue>
</nlm-citation>
</ref>
<ref id="B24">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Influencia de la inoculación micorrízica en los abonos verdes. Efecto sobre el cultivo principal. Estudio de caso: el maíz]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Martín]]></surname>
<given-names><![CDATA[G.M.]]></given-names>
</name>
<name>
<surname><![CDATA[Rivera]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
</person-group>
<source><![CDATA[Cultivos trop.]]></source>
<year>2015</year>
<volume>36</volume>
<page-range>34-50</page-range></nlm-citation>
</ref>
<ref id="B25">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Consumo voluntario de forraje por rumiantes en pastoreo]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Mejía]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
</person-group>
<source><![CDATA[Acta Universitaria]]></source>
<year>2002</year>
<volume>12</volume>
<numero>3</numero>
<issue>3</issue>
<page-range>56-63</page-range></nlm-citation>
</ref>
<ref id="B26">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Mendoza]]></surname>
<given-names><![CDATA[C.A.]]></given-names>
</name>
</person-group>
<source><![CDATA[Efecto de la variación diaria en la oferta forrajera sobre el volumen y composición de la leche en explotaciones de la Sabana de Bogotá]]></source>
<year>2011</year>
<publisher-loc><![CDATA[Bogotá, COL ]]></publisher-loc>
<publisher-name><![CDATA[Universidad Nacional de Colombia]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B27">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Mertens]]></surname>
<given-names><![CDATA[D.R.]]></given-names>
</name>
</person-group>
<source><![CDATA[Applications of theoretical mathematicals models to cell wall digestion and forage intake in ruminants]]></source>
<year>1973</year>
<publisher-loc><![CDATA[Ithaca, NY., USA ]]></publisher-loc>
<publisher-name><![CDATA[Cornell Univ.]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B28">
<nlm-citation citation-type="book">
<collab>NRC (National Research Council)</collab>
<source><![CDATA[Nutrients requirements of dairy cattle]]></source>
<year>2001</year>
<edition>7</edition>
<publisher-loc><![CDATA[WA, USA ]]></publisher-loc>
<publisher-name><![CDATA[National Academy Press]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B29">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Effects of confinement and level of feed intake on digestibility of nutrients and excretion of chromic oxide, crude protein and gross energy in the bovine]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Phar]]></surname>
<given-names><![CDATA[P.A.]]></given-names>
</name>
<name>
<surname><![CDATA[Bradley]]></surname>
<given-names><![CDATA[N.W.]]></given-names>
</name>
<name>
<surname><![CDATA[Little]]></surname>
<given-names><![CDATA[C.O.]]></given-names>
</name>
<name>
<surname><![CDATA[Cundiff]]></surname>
<given-names><![CDATA[L.V.]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Anim. Sci.]]></source>
<year>1970</year>
<volume>30</volume>
<page-range>589-92</page-range></nlm-citation>
</ref>
<ref id="B30">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Herbage selection, intake and digestibility in grazing beef cattle]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Reis]]></surname>
<given-names><![CDATA[S.F.]]></given-names>
</name>
<name>
<surname><![CDATA[Huntington]]></surname>
<given-names><![CDATA[G.]]></given-names>
</name>
<name>
<surname><![CDATA[Hopkins]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Whisnant]]></surname>
<given-names><![CDATA[S.]]></given-names>
</name>
<name>
<surname><![CDATA[Paulino]]></surname>
<given-names><![CDATA[P.V.]]></given-names>
</name>
</person-group>
<source><![CDATA[Liv. Sci.]]></source>
<year>2015</year>
<volume>174</volume>
<page-range>39-45</page-range></nlm-citation>
</ref>
<ref id="B31">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Efecto de la oferta y el consumo de Tithonia diversifolia en un sistema silvopastoril intensivo (SSPi), en la calidad y productividad de leche bovina en el piedemonte Amazónico colombiano]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Rivera]]></surname>
<given-names><![CDATA[J.E.]]></given-names>
</name>
<name>
<surname><![CDATA[Cuartas]]></surname>
<given-names><![CDATA[C.A.]]></given-names>
</name>
<name>
<surname><![CDATA[Naranjo]]></surname>
<given-names><![CDATA[J.F.]]></given-names>
</name>
<name>
<surname><![CDATA[Tafur]]></surname>
<given-names><![CDATA[O.]]></given-names>
</name>
<name>
<surname><![CDATA[Hurtado]]></surname>
<given-names><![CDATA[E.A.]]></given-names>
</name>
<name>
<surname><![CDATA[Arenas]]></surname>
<given-names><![CDATA[F.A.]]></given-names>
</name>
<name>
<surname><![CDATA[Chará]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<name>
<surname><![CDATA[Murgueitio]]></surname>
<given-names><![CDATA[E.]]></given-names>
</name>
</person-group>
<source><![CDATA[Liv. Res. Rural Dev.]]></source>
<year>2015</year>
<volume>27</volume>
<numero>10</numero>
<issue>10</issue>
</nlm-citation>
</ref>
<ref id="B32">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Two drying methods of bovine faeces for estimating n-alkane concentration, intake and digestibility: A comparison]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Sánchez-Chopa]]></surname>
<given-names><![CDATA[F.]]></given-names>
</name>
<name>
<surname><![CDATA[Nadin]]></surname>
<given-names><![CDATA[L.B.]]></given-names>
</name>
<name>
<surname><![CDATA[Gonda]]></surname>
<given-names><![CDATA[H.L.]]></given-names>
</name>
</person-group>
<source><![CDATA[Anim. Feed Sci. Technol.]]></source>
<year>2012</year>
<volume>177</volume>
<page-range>1-6</page-range></nlm-citation>
</ref>
<ref id="B33">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Sierra]]></surname>
<given-names><![CDATA[J.O.]]></given-names>
</name>
</person-group>
<source><![CDATA[Producción y manejo agroecológico de pasturas y cultivos forrajeros en el trópico: para una ganadería natural más limpia, eficiente y sostenible]]></source>
<year>2011</year>
<publisher-loc><![CDATA[Medellín, COL. ]]></publisher-loc>
<publisher-name><![CDATA[Editorial Universidad de Antioquia]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B34">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Treviño]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<name>
<surname><![CDATA[Centeno]]></surname>
<given-names><![CDATA[C.]]></given-names>
</name>
<name>
<surname><![CDATA[Caballero]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
</person-group>
<source><![CDATA[Efecto de la aplicación de diferentes dosis de nitrógeno sobre la composición de la fracción nitrogenada del Lolium multiflorum var. Westerwoldicum]]></source>
<year>2011</year>
<publisher-loc><![CDATA[Madrid, ESP ]]></publisher-loc>
<publisher-name><![CDATA[Instituto de Alimentación y Productividad Animal (CSIC)]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B35">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Van-Soest]]></surname>
<given-names><![CDATA[P.J.]]></given-names>
</name>
<name>
<surname><![CDATA[Robertson]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
</person-group>
<source><![CDATA[Analysis of forages and fibrous of the feeds]]></source>
<year>1985</year>
<publisher-loc><![CDATA[Ithaca, NY, USA. ]]></publisher-loc>
<publisher-name><![CDATA[Cornell University]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B36">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Velez]]></surname>
<given-names><![CDATA[O.M.]]></given-names>
</name>
</person-group>
<source><![CDATA[Análisis de las limitaciones nutricionales y de manejo en un sistema de producción lechera en el Valle del Cauca]]></source>
<year>2011</year>
<publisher-loc><![CDATA[COL ]]></publisher-loc>
<publisher-name><![CDATA[Universidad Nacional de Colombia]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B37">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Evaluación agronómica y nutricional del pasto ryegrass perenne tetraploide (Lolium perenne) producido en lecherías de las zonas altas de Costa Rica. II. Valor nutricional.]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Villalobos]]></surname>
<given-names><![CDATA[L.]]></given-names>
</name>
<name>
<surname><![CDATA[Sánchez]]></surname>
<given-names><![CDATA[J.M.]]></given-names>
</name>
</person-group>
<source><![CDATA[Agron. Costarricense]]></source>
<year>2010</year>
<volume>34</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>43-52</page-range></nlm-citation>
</ref>
<ref id="B38">
<nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[The determination of chromic oxide in faeces samples by atomic absorption spectrophotometry]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Williams]]></surname>
<given-names><![CDATA[C.H.]]></given-names>
</name>
<name>
<surname><![CDATA[David]]></surname>
<given-names><![CDATA[D.J.]]></given-names>
</name>
<name>
<surname><![CDATA[Lismaa]]></surname>
<given-names><![CDATA[O.]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Agric. Sci.]]></source>
<year>1962</year>
<volume>59</volume>
<page-range>381-5</page-range></nlm-citation>
</ref>
</ref-list>
</back>
</article>
