<?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>S1659-13212021000200573</article-id>
<article-id pub-id-type="doi">10.15517/am.v32i2.39673</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Factibilidad de la producción de huevos de gallinas ponedoras con acceso a pastoreo]]></article-title>
<article-title xml:lang="en"><![CDATA[Egg production feasibility in laying hen with access to grazing]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Cruz-Bermúdez]]></surname>
<given-names><![CDATA[Ana]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[WingChing-Jones]]></surname>
<given-names><![CDATA[Rodolfo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Zamora-Sanabria]]></surname>
<given-names><![CDATA[Rebeca]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad de Costa Rica  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Costa Rica</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad de Costa Rica  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Costa Rica</country>
</aff>
<aff id="Af3">
<institution><![CDATA[,Universidad de Costa Rica  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Costa Rica</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>08</month>
<year>2021</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>08</month>
<year>2021</year>
</pub-date>
<volume>32</volume>
<numero>2</numero>
<fpage>573</fpage>
<lpage>586</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_arttext&amp;pid=S1659-13212021000200573&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_abstract&amp;pid=S1659-13212021000200573&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_pdf&amp;pid=S1659-13212021000200573&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen Introducción. La producción de gallinas con acceso a pastoreo integra el manejo del ave, forraje y la comercialización. Objetivo. Describir los sistemas de producción de gallinas ponedoras con acceso a pastoreo en Costa Rica y determinar la factibilidad de la implementación de un modelo de producción. Materiales y Métodos. Durante los años 2017 y 2018, se recolectó y analizó la información de producción, sanidad, pastoreo y manejo del huevo en seis granjas con aves de postura que presentan acceso al pastoreo. Para determinar la factibilidad del modelo de producción propuesto, se elaboró un flujo de caja (diez años), que contempló las inversiones para el desarrollo del sistema y una tasa de inflación del 10 % a través de los años. Se calcularon los costos de inversión, operación e ingresos por venta de huevo, gallinas de descarte y gallinaza. Se calcularon el VAN, TIR, relación B/C y punto de equilibrio. Resultados. El 66 % de los sistemas manejan aves especializadas, densidades entre 5 a 12 y 1 a 3 aves m-2 en el galpón y área de pastoreo respectivamente. El pastoreo se inició entre las 22 y 32 semanas, con sesiones de 2 a 10 horas día-1. Cinco sistemas no sustituyeron el alimento por forraje, lo consideran como aporte adicional. La propuesta, es demandante en instalaciones, terreno y equipo de trabajo. El alimento representó el 41 % de los costos operativos, seguido por el personal y la compra de las aves. Es rentable, al obtener un VAN positivo ($31 455,39), TIR de 21,48 %, una relación B/C&gt;1 y se recupera la inversión a los seis años. Conclusión. Las granjas con gallinas ponedoras con acceso a pastoreo podrían mejorar en aspectos nutricionales y del cultivo del forraje. Además, son sistemas de producción que presentan indicadores económicos que propician su implementación.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract Introduction. The production of hens with access to grazing integrates bird, fodder, and marketing management. Objective. To describe laying hens&#8217; production systems with grazing access in Costa Rica and determine the feasibility of implementing aproduction model. Materials and methods. During the years 2017 and 2018, information on the production, health, grazing, and egg management was collected and analyzed in six farms with laying birds that have access to grazing. To determine the feasibility of the proposed production model, a cash flow (ten years) was prepared, which included the investments to develop the system, and an inflation rate of 10% through the years. The costs of investment, operation, and income from the sale of the eggs, discarded hens, and poultry litter were analyzed. The NPV, IRR, C/B ratio, and break-even point were calculated. Results. Sixty six percent of the systems use specialized birds, densities between 5 to 12, and 1 to 3 birds m-2 in the shed and grazing area, respectively. Grazing began at 22 and 32 weeks, with 2-10 h day-1. Five systems did not substitute feed for fodder; they consider it as an added value. The proposal is demanding in facilities, plot, and work equipment. Feeds represent 41% of the operational costs, followed by labor (22 %), and bird purchase (17 %). It is profitable, by obtaining a positive NPV ($31 455.39) and IRR of 21.48 % and the C/B ratio&gt;1, and the investment will be recovered after six years. Conclusions. Farms with laying hens with access to grazing evaluated in this work could improve in nutritional aspects and forage cultivation. In addition, they are production systems that present economic indicators that favor their implementation.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[producción animal]]></kwd>
<kwd lng="es"><![CDATA[diagnóstico]]></kwd>
<kwd lng="es"><![CDATA[bienestar animal]]></kwd>
<kwd lng="es"><![CDATA[avicultura]]></kwd>
<kwd lng="en"><![CDATA[animal production]]></kwd>
<kwd lng="en"><![CDATA[diagnosis]]></kwd>
<kwd lng="en"><![CDATA[animal welfare]]></kwd>
<kwd lng="en"><![CDATA[poultry]]></kwd>
</kwd-group>
</article-meta>
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