<?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>2007-1124</journal-id>
<journal-title><![CDATA[Revista mexicana de ciencias pecuarias]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. mex. de cienc. pecuarias]]></abbrev-journal-title>
<issn>2007-1124</issn>
<publisher>
<publisher-name><![CDATA[Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2007-11242017000200201</article-id>
<article-id pub-id-type="doi">10.22319/rmcp.v8i2.4445</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Composición química, contenido mineral y digestibilidad in vitro de raigrás (Lolium perenne) según intervalo de corte y época de crecimiento]]></article-title>
<article-title xml:lang="en"><![CDATA[Chemical composition, mineral content and in vitro digestibility from ryegrass (Lolium perenne) in relation to the cutting interval and growing season]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Castro-Hernández]]></surname>
<given-names><![CDATA[Horacio]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Domínguez-Vara]]></surname>
<given-names><![CDATA[Ignacio Arturo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Morales-Almaráz]]></surname>
<given-names><![CDATA[Ernesto]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Huerta-Bravo]]></surname>
<given-names><![CDATA[Maximino]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Autónoma del Estado de México Facultad de Medicina Veterinaria y Zootecnia Depto. de Nutrición Animal]]></institution>
<addr-line><![CDATA[Toluca Estado de México]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad Autónoma Chapingo Depto. de Zootecnia ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>06</month>
<year>2017</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2017</year>
</pub-date>
<volume>8</volume>
<numero>2</numero>
<fpage>201</fpage>
<lpage>210</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S2007-11242017000200201&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S2007-11242017000200201&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S2007-11242017000200201&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[RESUMEN El objetivo fue evaluar la calidad nutritiva del forraje raigrás (Lolium perenne) a diferente madurez (0, 7, 14 y 28 días) en tres épocas del año, otoño (O), invierno (I) y primavera-verano (PV), en un diseño experimental completamente al azar con arreglo factorial 4x3. La madurez del forraje aumentó de forma lineal y cuadrática el contenido de materia seca, fibra detergente ácido y lignina ácido detergente, y de forma cuadrática la fibra detergente neutro; la materia orgánica (MO) bajó de forma lineal y cuadrática, y la proteína cruda (PC) disminuyó linealmente al madurar el forraje. La MO y PC fueron mayores en PV (P&lt;0.01). La producción total de gas, degradabilidad y producción de gas relativa, bajaron de forma lineal y cuadrática (P&lt;0.05) al madurar la planta; la degradabilidad y producción de gas relativa fueron mayores al día cero y en la época PV; el volumen de gas por efecto del intervalo de corte, en las tres épocas, disminuyó con la edad del forraje. El tiempo de retardo de incubación fue mayor (P&lt;0.01) en PV. El contenido mineral del forraje se afectó (P&lt;0.05) por el intervalo de corte y época del año; el mayor aporte fue al día cero y en PV. Los niveles de P, Ca, K, Mg y Zn del forraje no cubren los requerimientos de vacas en producción en las distintas épocas y edades de corte evaluadas. El forraje tuvo mayor calidad en la época PV, antes de 28 días de edad.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[ABSTRACT The objective was to evaluate the nutritive quality of forage ryegrass (Lolium perenne) at different maturity (0, 7, 14 and 28 d) in three seasons of the year, autumn (A), winter (W) and spring-summer (SS) in an experimental design randomized with factorial treatments 4x3 arrangement. The maturity of the plant increased in linear and quadratic form the content of dry matter, acid detergent fiber and acid detergent lignin, and quadratic form of neutral detergent fiber; organic matter (OM) content fell in linear and quadratic form and the crude protein (CP) is reduced linearly by the maturity of the forage. The biggest contribution of OM and CP was in SS (P&lt;0.01). Total gas production, degradability and relative gas production, fell in linear and quadratic form (P&lt;0.05) with the maturity of the plant. Degradability and relative gas production were greater in the zero-day and at the season SS; the volume of gas produced by cutting interval effect, in three times, decreased with the age of the forage. The delay time of incubation was greatest (P&lt;0.01) in SS. The mineral concentration in the forage was affected (P&lt;0.05) by the range of cutting and the season of year; higher mineral content was in the zero-day cut and in SS. Concentrations of P, Ca, K, Mg, and Zn do not meet requirements for lactating cows at any seasons by maturity stage combination. The best forage quality was obtained in SS before 28 d of regrowth age.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Composición química]]></kwd>
<kwd lng="es"><![CDATA[Época]]></kwd>
<kwd lng="es"><![CDATA[Minerales]]></kwd>
<kwd lng="es"><![CDATA[Digestibilidad]]></kwd>
<kwd lng="es"><![CDATA[Madurez]]></kwd>
<kwd lng="es"><![CDATA[Raigrás]]></kwd>
<kwd lng="en"><![CDATA[Chemical composition]]></kwd>
<kwd lng="en"><![CDATA[Minerals]]></kwd>
<kwd lng="en"><![CDATA[Digestibility]]></kwd>
<kwd lng="en"><![CDATA[Age]]></kwd>
<kwd lng="en"><![CDATA[Season]]></kwd>
<kwd lng="en"><![CDATA[Ryegrass]]></kwd>
</kwd-group>
</article-meta>
</front><back>
<ref-list>
<ref id="B1">
<label>1</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Hernández-Garay]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
<name>
<surname><![CDATA[Matthew]]></surname>
<given-names><![CDATA[C]]></given-names>
</name>
<name>
<surname><![CDATA[Hodgson]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Effect of spring grazing management of perennial ryegrass and ryegrass-white clover pastures. 1. Tissue turnover and herbage accumulation]]></article-title>
<source><![CDATA[N Z J Agr Res]]></source>
<year>1997</year>
<volume>40</volume>
<page-range>25-35</page-range></nlm-citation>
</ref>
<ref id="B2">
<label>2</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Richards]]></surname>
<given-names><![CDATA[JH]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Physiology of plants recovering from defoliation. Proc XVII Int Grassland Cong]]></article-title>
<source><![CDATA[N Z and Australia]]></source>
<year>1993</year>
<page-range>85-94</page-range></nlm-citation>
</ref>
<ref id="B3">
<label>3</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Velasco-Zebadúa]]></surname>
<given-names><![CDATA[ME]]></given-names>
</name>
<name>
<surname><![CDATA[Hernández]]></surname>
<given-names><![CDATA[GA]]></given-names>
</name>
<name>
<surname><![CDATA[González]]></surname>
<given-names><![CDATA[HV]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Rendimiento y valor nutritivo del Ballico perenne (Lolium perenne) en respuesta a la frecuencia de corte]]></article-title>
<source><![CDATA[Téc Pecu Méx]]></source>
<year>2005</year>
<volume>43</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>247-58</page-range></nlm-citation>
</ref>
<ref id="B4">
<label>4</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Posada]]></surname>
<given-names><![CDATA[SL]]></given-names>
</name>
<name>
<surname><![CDATA[Noguera]]></surname>
<given-names><![CDATA[RR]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Técnica in vitro de producción de gases: una herramienta para la evaluación de alimentos para rumiantes]]></article-title>
<source><![CDATA[Liv Res Rural Develop]]></source>
<year>2005</year>
<volume>17</volume>
<numero>4</numero>
<issue>4</issue>
<page-range>450-65</page-range></nlm-citation>
</ref>
<ref id="B5">
<label>5</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Russel]]></surname>
<given-names><![CDATA[JB]]></given-names>
</name>
<name>
<surname><![CDATA[O`Connor]]></surname>
<given-names><![CDATA[JD]]></given-names>
</name>
<name>
<surname><![CDATA[Fox]]></surname>
<given-names><![CDATA[DG]]></given-names>
</name>
<name>
<surname><![CDATA[Van Soest]]></surname>
<given-names><![CDATA[PJ]]></given-names>
</name>
<name>
<surname><![CDATA[Sniffen]]></surname>
<given-names><![CDATA[CJ]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[A net carbohydrate and protein system for evaluating cattle diets: I. Ruminant fermentation]]></article-title>
<source><![CDATA[J Anim Sci]]></source>
<year>1992</year>
<volume>70</volume>
<page-range>3551-61</page-range></nlm-citation>
</ref>
<ref id="B6">
<label>6</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[López]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
<name>
<surname><![CDATA[Carro]]></surname>
<given-names><![CDATA[MD]]></given-names>
</name>
<name>
<surname><![CDATA[González]]></surname>
<given-names><![CDATA[JS]]></given-names>
</name>
<name>
<surname><![CDATA[Ovejero]]></surname>
<given-names><![CDATA[FJ]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Comparison of different in vitro and in situ methods to estimate the extent and rate of degradation of hays in rumen]]></article-title>
<source><![CDATA[Anim Feed Sci Tech]]></source>
<year>1998</year>
<volume>73</volume>
<page-range>99-113</page-range></nlm-citation>
</ref>
<ref id="B7">
<label>7</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Lemus]]></surname>
<given-names><![CDATA[RV]]></given-names>
</name>
<name>
<surname><![CDATA[Lugo]]></surname>
<given-names><![CDATA[LG]]></given-names>
</name>
<name>
<surname><![CDATA[Valencia]]></surname>
<given-names><![CDATA[GE]]></given-names>
</name>
<name>
<surname><![CDATA[Villagrán]]></surname>
<given-names><![CDATA[VB]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Desempeño de una pradera irrigada en clima templado, establecida para el pastoreo con bovinos lecheros]]></article-title>
<source><![CDATA[Vet Méx]]></source>
<year>2002</year>
<volume>33</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>11:26</page-range></nlm-citation>
</ref>
<ref id="B8">
<label>8</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Arriaga]]></surname>
<given-names><![CDATA[JC]]></given-names>
</name>
<name>
<surname><![CDATA[Espinoza]]></surname>
<given-names><![CDATA[OA]]></given-names>
</name>
<name>
<surname><![CDATA[Albarrán]]></surname>
<given-names><![CDATA[PB]]></given-names>
</name>
<name>
<surname><![CDATA[Castelán]]></surname>
<given-names><![CDATA[OO]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Producción de leche en pastoreo de praderas cultivadas: Una alternativa para el altiplano central]]></article-title>
<source><![CDATA[Ciencia Ergo Sum]]></source>
<year>1999</year>
<volume>6</volume>
<page-range>290-300</page-range></nlm-citation>
</ref>
<ref id="B9">
<label>9</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Álvarez]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
<name>
<surname><![CDATA[Cervantes]]></surname>
<given-names><![CDATA[F]]></given-names>
</name>
<name>
<surname><![CDATA[Espinoza]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Características del sistema lácteo y sus principales tendencias en México]]></article-title>
<person-group person-group-type="editor">
<name>
<surname><![CDATA[Álvarez]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
</person-group>
<source><![CDATA[Agroindustria rural y territorio. Nuevas tendencias en el análisis de la lechería]]></source>
<year>2007</year>
<numero>2</numero>
<issue>2</issue>
<page-range>15-52</page-range><publisher-loc><![CDATA[Toluca, México ]]></publisher-loc>
<publisher-name><![CDATA[UAEM]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B10">
<label>10</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Minson]]></surname>
<given-names><![CDATA[DJ]]></given-names>
</name>
</person-group>
<source><![CDATA[Forages in ruminant nutrition]]></source>
<year>1990</year>
<edition>1</edition>
<publisher-loc><![CDATA[USA ]]></publisher-loc>
<publisher-name><![CDATA[Academic Press]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B11">
<label>11</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Hodgson]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[Brookes]]></surname>
<given-names><![CDATA[IM]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Nutrition of grazing animals. Chapter 9]]></article-title>
<person-group person-group-type="editor">
<name>
<surname><![CDATA[White]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[Hodgson]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
</person-group>
<source><![CDATA[N Z Pastures Crop Sci]]></source>
<year>1999</year>
<page-range>117-32</page-range><publisher-name><![CDATA[Oxford Univ Press]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B12">
<label>12</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Hodgson]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
</person-group>
<source><![CDATA[Grazing management: science into practice. Longman handbooks in agriculture]]></source>
<year>1990</year>
<publisher-loc><![CDATA[New York ]]></publisher-loc>
<publisher-name><![CDATA[Longman Scientific and Technical and John Wiley]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B13">
<label>13</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Machado]]></surname>
<given-names><![CDATA[CF]]></given-names>
</name>
<name>
<surname><![CDATA[Morris]]></surname>
<given-names><![CDATA[ST]]></given-names>
</name>
<name>
<surname><![CDATA[Hodgson]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[Fathalla]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Seasonal changes of herbage quality within a New Zealand beef cattle finishing pasture]]></article-title>
<source><![CDATA[N Z J Agr Res]]></source>
<year>2005</year>
<volume>48</volume>
<page-range>265-70</page-range></nlm-citation>
</ref>
<ref id="B14">
<label>14</label><nlm-citation citation-type="">
<collab>Instituto Nacional de Estadística, Geografía e Informática</collab>
<source><![CDATA[Prontuario de información geográfica municipal de los Estados Unidos Mexicanos]]></source>
<year>2009</year>
<publisher-loc><![CDATA[México ]]></publisher-loc>
</nlm-citation>
</ref>
<ref id="B15">
<label>15</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[McDowell]]></surname>
<given-names><![CDATA[LR]]></given-names>
</name>
<name>
<surname><![CDATA[Conrad]]></surname>
<given-names><![CDATA[JH]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Trace mineral nutrition in Latin America]]></article-title>
<source><![CDATA[World Anim Rev]]></source>
<year>1977</year>
<volume>6</volume>
<numero>24</numero>
<issue>24</issue>
<page-range>24:33</page-range></nlm-citation>
</ref>
<ref id="B16">
<label>16</label><nlm-citation citation-type="">
<collab>Instituto Nacional de Estadística, Geografía e Informática</collab>
<source><![CDATA[Anuario estadístico]]></source>
<year>2004</year>
<publisher-loc><![CDATA[México ]]></publisher-loc>
</nlm-citation>
</ref>
<ref id="B17">
<label>17</label><nlm-citation citation-type="book">
<collab>Association of Official Analytical Chemists</collab>
<source><![CDATA[Official methods of analysis]]></source>
<year>1990</year>
<publisher-loc><![CDATA[Arlington, VA, USA ]]></publisher-loc>
<publisher-name><![CDATA[Association of Official Analytical Chemists]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B18">
<label>18</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Van Soest]]></surname>
<given-names><![CDATA[PJ]]></given-names>
</name>
<name>
<surname><![CDATA[Robertson]]></surname>
<given-names><![CDATA[JB]]></given-names>
</name>
<name>
<surname><![CDATA[Lewis]]></surname>
<given-names><![CDATA[BA]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Methods for dietary fiber, neutral detergent fiber and nonstarch polysaccharides in relation to animal nutrition]]></article-title>
<source><![CDATA[J Dairy Sci]]></source>
<year>1991</year>
<volume>74</volume>
<numero>10</numero>
<issue>10</issue>
<page-range>3583-97</page-range></nlm-citation>
</ref>
<ref id="B19">
<label>19</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Theodorou]]></surname>
<given-names><![CDATA[KM]]></given-names>
</name>
<name>
<surname><![CDATA[Williams]]></surname>
<given-names><![CDATA[AB]]></given-names>
</name>
<name>
<surname><![CDATA[Dhanoa]]></surname>
<given-names><![CDATA[SM]]></given-names>
</name>
<name>
<surname><![CDATA[McAllan]]></surname>
<given-names><![CDATA[BA]]></given-names>
</name>
<name>
<surname><![CDATA[France]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[A simple gas production method using a pressure transducer to determine the fermentation kinetics of ruminant feeds]]></article-title>
<source><![CDATA[Anim Feed Sci Technol]]></source>
<year>1994</year>
<volume>48</volume>
<numero>3</numero>
<issue>3</issue>
<page-range>185-97</page-range></nlm-citation>
</ref>
<ref id="B20">
<label>20</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[González-Ronquillo]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<name>
<surname><![CDATA[Fondevila]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<name>
<surname><![CDATA[Barrios-Urdaneta]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
<name>
<surname><![CDATA[Newman]]></surname>
<given-names><![CDATA[Y]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[In vitro gas production from buffel grass (Cenchrus ciliaris L.) fermentation in relation to the cutting interval, the level of nitrogen fertilization and the season of growth]]></article-title>
<source><![CDATA[Anim Feed Sci Tech]]></source>
<year>1998</year>
<volume>72</volume>
<page-range>19-32</page-range></nlm-citation>
</ref>
<ref id="B21">
<label>21</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<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[Theodorou]]></surname>
<given-names><![CDATA[MK]]></given-names>
</name>
<name>
<surname><![CDATA[Lister]]></surname>
<given-names><![CDATA[SJ]]></given-names>
</name>
<name>
<surname><![CDATA[Davies]]></surname>
<given-names><![CDATA[DR]]></given-names>
</name>
<name>
<surname><![CDATA[Isaac]]></surname>
<given-names><![CDATA[D]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[A model to interpret gas accumulation profiles associated with in vitro degradation of ruminant feeds]]></article-title>
<source><![CDATA[J Theor Biol]]></source>
<year>1993</year>
<volume>163</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>99-111</page-range></nlm-citation>
</ref>
<ref id="B22">
<label>22</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Harris]]></surname>
<given-names><![CDATA[WD]]></given-names>
</name>
<name>
<surname><![CDATA[Popat]]></surname>
<given-names><![CDATA[P]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Determination of the phosphorus content of lipids]]></article-title>
<source><![CDATA[J Am Oil Chem Soc]]></source>
<year>1954</year>
<volume>31</volume>
<numero>4</numero>
<issue>4</issue>
<page-range>124-7</page-range></nlm-citation>
</ref>
<ref id="B23">
<label>23</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Fick]]></surname>
<given-names><![CDATA[KR]]></given-names>
</name>
<name>
<surname><![CDATA[McDowell]]></surname>
<given-names><![CDATA[LR]]></given-names>
</name>
<name>
<surname><![CDATA[Wilkinson]]></surname>
<given-names><![CDATA[NS]]></given-names>
</name>
<name>
<surname><![CDATA[Funk]]></surname>
<given-names><![CDATA[DJ]]></given-names>
</name>
<name>
<surname><![CDATA[Conrad]]></surname>
<given-names><![CDATA[JH]]></given-names>
</name>
<name>
<surname><![CDATA[Valdivia]]></surname>
<given-names><![CDATA[R]]></given-names>
</name>
</person-group>
<source><![CDATA[Métodos de análisis de minerales para tejidos de plantas y animales]]></source>
<year>1979</year>
<publisher-loc><![CDATA[Florida, USA ]]></publisher-loc>
<publisher-name><![CDATA[Departamento de Ciencia Animal, Universidad de Florida]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B24">
<label>24</label><nlm-citation citation-type="book">
<collab>SAS</collab>
<source><![CDATA[SAS/STAT User´s Guide: Statistics (version 8)]]></source>
<year>1999</year>
<publisher-loc><![CDATA[Cary NC. USA ]]></publisher-loc>
<publisher-name><![CDATA[SAS Inst. Inc. Statistical Analysis System Institute]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B25">
<label>25</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Steel]]></surname>
<given-names><![CDATA[RGD]]></given-names>
</name>
<name>
<surname><![CDATA[Torrie]]></surname>
<given-names><![CDATA[JH]]></given-names>
</name>
</person-group>
<source><![CDATA[Principles and procedures of statistics: a biometrical approach]]></source>
<year>1980</year>
<edition>2</edition>
<publisher-loc><![CDATA[New York, USA ]]></publisher-loc>
<publisher-name><![CDATA[Mcgraw-Hill Book Co]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B26">
<label>26</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Matthew]]></surname>
<given-names><![CDATA[C]]></given-names>
</name>
<name>
<surname><![CDATA[Hodgson]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
</person-group>
<source><![CDATA[Form and function of grass]]></source>
<year>1997</year>
<publisher-loc><![CDATA[New Zealand ]]></publisher-loc>
<publisher-name><![CDATA[Grassview Inst Nat Resources]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B27">
<label>27</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[García]]></surname>
<given-names><![CDATA[E]]></given-names>
</name>
</person-group>
<source><![CDATA[Modificaciones al sistema de clasificación climática de Köppen]]></source>
<year>1988</year>
<edition>4</edition>
<publisher-loc><![CDATA[México ]]></publisher-loc>
<publisher-name><![CDATA[Universidad Nacional Autónoma de México]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B28">
<label>28</label><nlm-citation citation-type="book">
<collab>National Research Council</collab>
<source><![CDATA[Nutrient requirements of dairy cattle]]></source>
<year>2001</year>
<edition>7</edition>
<publisher-loc><![CDATA[Washington, DC, USA ]]></publisher-loc>
<publisher-name><![CDATA[National Academic Press]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B29">
<label>29</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Lozano]]></surname>
<given-names><![CDATA[AJ]]></given-names>
</name>
<name>
<surname><![CDATA[Rodríguez]]></surname>
<given-names><![CDATA[HSA]]></given-names>
</name>
<name>
<surname><![CDATA[Díaz]]></surname>
<given-names><![CDATA[SH]]></given-names>
</name>
<name>
<surname><![CDATA[Rodríguez]]></surname>
<given-names><![CDATA[FJM]]></given-names>
</name>
<name>
<surname><![CDATA[Fernández]]></surname>
<given-names><![CDATA[BJM]]></given-names>
</name>
<name>
<surname><![CDATA[Narváez]]></surname>
<given-names><![CDATA[MJM]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Producción de forraje y calidad nutritiva en mezclas de triticale (X Triticosecale Wittmack) y ballico anual (Lolium multiflorum L.) en Navidad, NL]]></article-title>
<source><![CDATA[Tec Pecu Méx]]></source>
<year>2002</year>
<volume>40</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>17-35</page-range></nlm-citation>
</ref>
<ref id="B30">
<label>30</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Mosquera-Lozada]]></surname>
<given-names><![CDATA[MR]]></given-names>
</name>
<name>
<surname><![CDATA[González-Rodríguez]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
<name>
<surname><![CDATA[Rigueiro-Rodríguez]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Sward quality affected by different grazing pressures on dairy systems]]></article-title>
<source><![CDATA[J Range Manage]]></source>
<year>2000</year>
<volume>53</volume>
<numero>6</numero>
<issue>6</issue>
<page-range>603-10</page-range></nlm-citation>
</ref>
<ref id="B31">
<label>31</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Jung]]></surname>
<given-names><![CDATA[AG]]></given-names>
</name>
<name>
<surname><![CDATA[Allen]]></surname>
<given-names><![CDATA[MS]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Characteristics of plants cell walls affecting intake and digestibility of forages by ruminants]]></article-title>
<source><![CDATA[J Anim Sci]]></source>
<year>1995</year>
<volume>73</volume>
<page-range>2774-90</page-range></nlm-citation>
</ref>
<ref id="B32">
<label>32</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Ribeiro Jr]]></surname>
<given-names><![CDATA[GO]]></given-names>
</name>
<name>
<surname><![CDATA[Teixeira]]></surname>
<given-names><![CDATA[AM]]></given-names>
</name>
<name>
<surname><![CDATA[Velasco]]></surname>
<given-names><![CDATA[FO]]></given-names>
</name>
<name>
<surname><![CDATA[Faria Júnior]]></surname>
<given-names><![CDATA[WG]]></given-names>
</name>
<name>
<surname><![CDATA[Pereira]]></surname>
<given-names><![CDATA[LGR]]></given-names>
</name>
<name>
<surname><![CDATA[Chaves]]></surname>
<given-names><![CDATA[AV]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Production, nutritional quality and in vitro methane production from Andropogon gayanus grass harvested at different maturities and preserved as hay or Silage]]></article-title>
<source><![CDATA[Asian Austral J Anim Sci]]></source>
<year>2014</year>
<volume>27</volume>
<numero>3</numero>
<issue>3</issue>
<page-range>330-41</page-range></nlm-citation>
</ref>
<ref id="B33">
<label>33</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Getachew]]></surname>
<given-names><![CDATA[G]]></given-names>
</name>
<name>
<surname><![CDATA[Blummel]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<name>
<surname><![CDATA[Makkar]]></surname>
<given-names><![CDATA[H]]></given-names>
</name>
<name>
<surname><![CDATA[Becker]]></surname>
<given-names><![CDATA[K]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[In vitro measures techniques for assesment of nutritional quality of feeds: review]]></article-title>
<source><![CDATA[Anim Feed Sci Tech]]></source>
<year>1998</year>
<volume>72</volume>
<page-range>261-81</page-range></nlm-citation>
</ref>
<ref id="B34">
<label>34</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Rosero]]></surname>
<given-names><![CDATA[JR]]></given-names>
</name>
</person-group>
<source><![CDATA[Estudio químico &#8220;in situ&#8221;, &#8220;in vitro&#8221; e microscópico da parede celular de cinco genotipos de sorgo colhidos em três epocas de corte]]></source>
<year>2002</year>
<publisher-loc><![CDATA[Bello Horizonte ]]></publisher-loc>
<publisher-name><![CDATA[Esola de Veterinária da Universidade Federal de Minas Gerais]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B35">
<label>35</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Schofield]]></surname>
<given-names><![CDATA[P]]></given-names>
</name>
<name>
<surname><![CDATA[Pitt]]></surname>
<given-names><![CDATA[RE]]></given-names>
</name>
<name>
<surname><![CDATA[Pell]]></surname>
<given-names><![CDATA[AN]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Kinnetics and fiber digestion from in vitro gas production]]></article-title>
<source><![CDATA[J Anim Sci]]></source>
<year>1994</year>
<volume>72</volume>
<page-range>2980-91</page-range></nlm-citation>
</ref>
<ref id="B36">
<label>36</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Makkar]]></surname>
<given-names><![CDATA[H]]></given-names>
</name>
</person-group>
<source><![CDATA[Recent advances in in vitro gas method for evaluation of nutritional quality of feed resources]]></source>
<year>2001</year>
</nlm-citation>
</ref>
<ref id="B37">
<label>37</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Grant]]></surname>
<given-names><![CDATA[RJ]]></given-names>
</name>
<name>
<surname><![CDATA[Mertens]]></surname>
<given-names><![CDATA[DR]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Impact of in vitro fermentation techniques upon kinetics of fiber digestion]]></article-title>
<source><![CDATA[J Dairy Sci]]></source>
<year>1992</year>
<volume>75</volume>
<page-range>1263-72</page-range></nlm-citation>
</ref>
<ref id="B38">
<label>38</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Pérez]]></surname>
<given-names><![CDATA[PJ]]></given-names>
</name>
<name>
<surname><![CDATA[González]]></surname>
<given-names><![CDATA[MSS]]></given-names>
</name>
<name>
<surname><![CDATA[Abarca]]></surname>
<given-names><![CDATA[BJA]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Rendimiento y digestibilidad de la materia seca de variedades de Lolium perenne L. con tres presiones de pastoreo]]></article-title>
<source><![CDATA[Agrociencia]]></source>
<year>1997</year>
<volume>31</volume>
<page-range>37-43</page-range></nlm-citation>
</ref>
<ref id="B39">
<label>39</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Valenciaga]]></surname>
<given-names><![CDATA[D]]></given-names>
</name>
<name>
<surname><![CDATA[Chongo]]></surname>
<given-names><![CDATA[B]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[La pared celular. Influencia de su naturaleza en la degradación microbiana ruminal de forrajes]]></article-title>
<source><![CDATA[Rev Cub Cienc Agríc]]></source>
<year>2004</year>
<volume>48</volume>
<numero>4</numero>
<issue>4</issue>
<page-range>343-50</page-range></nlm-citation>
</ref>
<ref id="B40">
<label>40</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Cone]]></surname>
<given-names><![CDATA[WJ]]></given-names>
</name>
<name>
<surname><![CDATA[Van Gelder]]></surname>
<given-names><![CDATA[AH]]></given-names>
</name>
<name>
<surname><![CDATA[Driehuis]]></surname>
<given-names><![CDATA[F]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Description of gas production profiles with a three-fasic model]]></article-title>
<source><![CDATA[Anim Feed Sci Tech]]></source>
<year>1997</year>
<volume>66</volume>
<page-range>31-45</page-range></nlm-citation>
</ref>
<ref id="B41">
<label>41</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Stefanon]]></surname>
<given-names><![CDATA[B]]></given-names>
</name>
<name>
<surname><![CDATA[Pell]]></surname>
<given-names><![CDATA[AN]]></given-names>
</name>
<name>
<surname><![CDATA[Schofield]]></surname>
<given-names><![CDATA[P]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Effect of maturity on digestion kinetics of water-soluble and water-insoluble fractions of alfalfa and brome hay]]></article-title>
<source><![CDATA[J Anim Sci]]></source>
<year>1996</year>
<volume>74</volume>
<page-range>1104-15</page-range></nlm-citation>
</ref>
<ref id="B42">
<label>42</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Bl&#971;mmel]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<name>
<surname><![CDATA[Mgomezulu]]></surname>
<given-names><![CDATA[R]]></given-names>
</name>
<name>
<surname><![CDATA[Chen]]></surname>
<given-names><![CDATA[XB]]></given-names>
</name>
<name>
<surname><![CDATA[Makkar]]></surname>
<given-names><![CDATA[HP]]></given-names>
</name>
<name>
<surname><![CDATA[Becker]]></surname>
<given-names><![CDATA[K]]></given-names>
</name>
<name>
<surname><![CDATA[Orskov]]></surname>
<given-names><![CDATA[ER]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The modification of an in vitro gas production test to detect roughage related differences an in vivo microbial protein synthesis as estimated by the excretion of purine derivatives]]></article-title>
<source><![CDATA[J Agric Sci]]></source>
<year>1999</year>
<volume>133</volume>
<page-range>335-40</page-range></nlm-citation>
</ref>
<ref id="B43">
<label>43</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Bl&#971;mmel]]></surname>
<given-names><![CDATA[N]]></given-names>
</name>
<name>
<surname><![CDATA[Becker]]></surname>
<given-names><![CDATA[K]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The degradability characteristics of fifty-four roughages of roughage neutral-detergent fibers as described by in vitro gas production and their relationship to voluntary feed intake]]></article-title>
<source><![CDATA[British J Nutr]]></source>
<year>1997</year>
<volume>77</volume>
<page-range>757-68</page-range></nlm-citation>
</ref>
<ref id="B44">
<label>44</label><nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Pell]]></surname>
<given-names><![CDATA[AN]]></given-names>
</name>
<name>
<surname><![CDATA[Doane]]></surname>
<given-names><![CDATA[PH]]></given-names>
</name>
<name>
<surname><![CDATA[Schofield]]></surname>
<given-names><![CDATA[P]]></given-names>
</name>
</person-group>
<source><![CDATA[In vitro digestibility and gas production]]></source>
<year>199</year>
<conf-name><![CDATA[ Simposio sobre Tópicos Speciais em Zootecnia]]></conf-name>
<conf-loc> </conf-loc>
</nlm-citation>
</ref>
<ref id="B45">
<label>45</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Suttle]]></surname>
<given-names><![CDATA[NF]]></given-names>
</name>
</person-group>
<source><![CDATA[Mineral nutrition of livestock]]></source>
<year>2010</year>
<edition>4</edition>
<publisher-loc><![CDATA[UK ]]></publisher-loc>
<publisher-name><![CDATA[CABI]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B46">
<label>46</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Morales]]></surname>
<given-names><![CDATA[AE]]></given-names>
</name>
<name>
<surname><![CDATA[Domínguez-Vara]]></surname>
<given-names><![CDATA[I]]></given-names>
</name>
<name>
<surname><![CDATA[González-Ronquillo]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<name>
<surname><![CDATA[Jaramillo]]></surname>
<given-names><![CDATA[EG]]></given-names>
</name>
<name>
<surname><![CDATA[Castelán]]></surname>
<given-names><![CDATA[OO]]></given-names>
</name>
<name>
<surname><![CDATA[Pescador]]></surname>
<given-names><![CDATA[SN]]></given-names>
</name>
<name>
<surname><![CDATA[Huerta]]></surname>
<given-names><![CDATA[BM]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Diagnóstico mineral en forrajes y suero sanguíneo de bovinos lecheros en dos épocas en el Valle central de México]]></article-title>
<source><![CDATA[Téc Pecu Méx]]></source>
<year>2007</year>
<volume>45</volume>
<numero>3</numero>
<issue>3</issue>
<page-range>329-44</page-range></nlm-citation>
</ref>
<ref id="B47">
<label>47</label><nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Huerta]]></surname>
<given-names><![CDATA[BM]]></given-names>
</name>
</person-group>
<source><![CDATA[Nutrición mineral de rumiantes en pastoreo]]></source>
<year>1997</year>
<conf-name><![CDATA[ Curso alternativas de manejo de bovinos carne en pastoreo]]></conf-name>
<conf-loc>Chapingo, México </conf-loc>
</nlm-citation>
</ref>
<ref id="B48">
<label>48</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[McDowell]]></surname>
<given-names><![CDATA[LR]]></given-names>
</name>
<name>
<surname><![CDATA[Valle]]></surname>
<given-names><![CDATA[G]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Major minerals in forages]]></article-title>
<person-group person-group-type="editor">
<name>
<surname><![CDATA[Givens]]></surname>
<given-names><![CDATA[DI]]></given-names>
</name>
</person-group>
<source><![CDATA[Forage evaluation in ruminant nutrition]]></source>
<year>2000</year>
<edition>1</edition>
<page-range>373-97</page-range><publisher-loc><![CDATA[UK ]]></publisher-loc>
<publisher-name><![CDATA[CABI]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B49">
<label>49</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Robinson]]></surname>
<given-names><![CDATA[D]]></given-names>
</name>
<name>
<surname><![CDATA[Kappel]]></surname>
<given-names><![CDATA[LC]]></given-names>
</name>
<name>
<surname><![CDATA[Boling]]></surname>
<given-names><![CDATA[JA]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Management practices to overcome the incidence of grass tetany]]></article-title>
<source><![CDATA[J Anim Sci]]></source>
<year>1989</year>
<volume>67</volume>
<page-range>3470-84</page-range></nlm-citation>
</ref>
<ref id="B50">
<label>50</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Humphries]]></surname>
<given-names><![CDATA[WR]]></given-names>
</name>
<name>
<surname><![CDATA[Bremner]]></surname>
<given-names><![CDATA[I]]></given-names>
</name>
<name>
<surname><![CDATA[Phillippo]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The influence of dietary iron on copper metabolism in the calf]]></article-title>
<person-group person-group-type="editor">
<name>
<surname><![CDATA[Mills]]></surname>
<given-names><![CDATA[CF]]></given-names>
</name>
</person-group>
<source><![CDATA[Trace elements in man and animals. Aberdeen, Scotland: Commonwealth Agric Bureaux]]></source>
<year>1985</year>
<page-range>371-3</page-range></nlm-citation>
</ref>
<ref id="B51">
<label>51</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[McDowell]]></surname>
<given-names><![CDATA[LR]]></given-names>
</name>
<name>
<surname><![CDATA[Houser]]></surname>
<given-names><![CDATA[RH]]></given-names>
</name>
<name>
<surname><![CDATA[Fick]]></surname>
<given-names><![CDATA[KR]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Iron, manganese and zinc in ruminant nutrition]]></article-title>
<person-group person-group-type="editor">
<name>
<surname><![CDATA[Conrad]]></surname>
<given-names><![CDATA[JH]]></given-names>
</name>
<name>
<surname><![CDATA[McDowell]]></surname>
<given-names><![CDATA[LR]]></given-names>
</name>
</person-group>
<source><![CDATA[Latin Am Symp Mineral Nutr Res Grazing Rum]]></source>
<year>1978</year>
<page-range>108-16</page-range><publisher-loc><![CDATA[Florida, USA ]]></publisher-loc>
<publisher-name><![CDATA[Universidad de Florida]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B52">
<label>52</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Domínguez-Vara]]></surname>
<given-names><![CDATA[I]]></given-names>
</name>
<name>
<surname><![CDATA[Huerta]]></surname>
<given-names><![CDATA[BM]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Concentración e interrelación mineral en suelo, forraje y suero de ovinos durante dos épocas en el valle de Toluca, México]]></article-title>
<source><![CDATA[Agrociencia]]></source>
<year>2008</year>
<volume>42</volume>
<numero>2</numero>
<issue>2</issue>
<page-range>173-83</page-range></nlm-citation>
</ref>
</ref-list>
</back>
</article>
