<?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>2448-6132</journal-id>
<journal-title><![CDATA[Abanico veterinario]]></journal-title>
<abbrev-journal-title><![CDATA[Abanico vet]]></abbrev-journal-title>
<issn>2448-6132</issn>
<publisher>
<publisher-name><![CDATA[Sergio Martínez González]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2448-61322016000200022</article-id>
<article-id pub-id-type="doi">10.21929/abavet2016.62.2</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Concentraciones séricas de progesterona al momento de la inseminación y tasa de gestación en vacas lecheras]]></article-title>
<article-title xml:lang="en"><![CDATA[Serum progesterone concentrations at the insemination time and pregnancy rate in dairy cows]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Moreno-Oliva]]></surname>
<given-names><![CDATA[Patricia]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Montaldo-Valdenegro]]></surname>
<given-names><![CDATA[Hugo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[García-Ortiz]]></surname>
<given-names><![CDATA[Carlos]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Hernández-Cerón]]></surname>
<given-names><![CDATA[Joel]]></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 ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>08</month>
<year>2016</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>08</month>
<year>2016</year>
</pub-date>
<volume>6</volume>
<numero>2</numero>
<fpage>22</fpage>
<lpage>29</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S2448-61322016000200022&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S2448-61322016000200022&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S2448-61322016000200022&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen: Se determinaron las concentraciones séricas de progesterona en la inseminación y su efecto en la tasa de gestación en vacas lecheras. Adicionalmente, se evaluaron los efectos del número de partos, número de servicios, tipo de puerperio, raza del toro, técnico inseminador y hato. Se obtuvieron muestras sanguíneas de 560 vacas de 25 hatos al momento de la inseminación y se determinaron las concentraciones de progesterona. El diagnóstico de gestación se realizó mediante palpación transrectal entre 40 y 50 días posinseminación. Por medio de regresión logística se determinó el efecto de la concentración de progesterona (&#8804;0.5ng/mL vs. &gt;0.5ng/mL), número de partos (primíparas vs. multíparas), número de servicios (&lt;4 servicios vs. &#8805;4 servicios), raza del toro (Holstein vs. otras razas), puerperio (normal vs. anormal), técnico (1 vs. 2) y hato, en la tasa de gestación. La proporción de vacas con valores de progesterona &gt;0.5 ng/mL fue de 5.9%. La tasa de gestación fue menor en las vacas que tuvieron concentraciones de progesterona &gt;0.5 ng/mL (18.2%) que en las vacas con &#8804;0.50 ng/mL (32.8%) (Odds ratio =2.46; P&lt;0.05). No se observó efecto (P&gt;0.05) del número de partos, número de servicios, raza del toro, puerperio, técnico ni del hato. Se concluye que 5.9% de las vacas tuvieron concentraciones suprabasales de progesterona al momento de la inseminación, lo cual afectó negativamente la tasa de gestación.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract: In this study the concentration of serum progesterone at the time of insemination and its effect on fertility in dairy cows were determined. In addition, it was assessed the impact of parity, number of services, puerperal condition, inseminating bull breed, AI technician and herd. Blood samples were obtained from 560 cows (25 herds) at the time of insemination and progesterone concentrations were determined. Pregnancy was diagnosed 40 to 45 days later by transrectal palpation. Using a logistic regression analysis the effect of progesterone (&#8804;0.5 vs. &gt;0.5 ng/mL), parity (primiparous vs. multiparous), number of services (&lt;4 vs. &#8805;4 services), bull breed (Holstein vs. other breeds), puerperal condition (normal vs. abnormal), AI technician (1 vs. 2) and herd on pregnancy rate were determined. The proportion of cows inseminated with values &gt;0.5 ng/mL was 5.9%. Cows with progesterone levels &gt;0.5 ng/mL had a lower conception rate (18.2) than cows with levels &#8804;0.50 ng/mL (32.8) (Odds ratio=2.46; P&lt;0.05). There was no significant effect (P&gt;0.05) of parity, number of services, breed of bull, AI technician, puerperal condition or herd. It is concluded that 5.9% of the cows had suprabasal progesterone concentrations at the time of insemination, which negatively affected the pregnancy rate.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[fertilidad]]></kwd>
<kwd lng="es"><![CDATA[vacas lecheras]]></kwd>
<kwd lng="es"><![CDATA[progesterona]]></kwd>
<kwd lng="en"><![CDATA[fertility]]></kwd>
<kwd lng="en"><![CDATA[dairy cattle]]></kwd>
<kwd lng="en"><![CDATA[progesterone]]></kwd>
</kwd-group>
</article-meta>
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