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  <front>
    <journal-meta>
      <journal-id journal-id-type="publisher-id">VETZOO</journal-id>
      <journal-title-group>
        <journal-title>Veterinarija ir Zootechnika</journal-title>
      </journal-title-group>
      <issn pub-type="epub"/>
      <issn pub-type="ppub"/>
      <publisher>
        <publisher-name>LSMU</publisher-name>
      </publisher>
    </journal-meta>
    <article-meta>
      <article-id pub-id-type="publisher-id">5</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Research article</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>Influence of Growth Retardation of Heifers on the Development, Production, Duration and Efficiency of Productive Lifespan of Dairy Cows</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <name>
            <surname>Polupan</surname>
            <given-names>Yuriy</given-names>
          </name>
          <email xlink:href="mailto:yupolupan@ukr.net">yupolupan@ukr.net</email>
          <xref ref-type="corresp" rid="cor1">∗</xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Stavetska</surname>
            <given-names>Ruslana</given-names>
          </name>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Melnyk</surname>
            <given-names>Yuriy</given-names>
          </name>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Siryak</surname>
            <given-names>Vitaliy</given-names>
          </name>
        </contrib>
      </contrib-group>
      <author-notes>
        <corresp id="cor1"><label>∗</label>Corresponding author.</corresp>
      </author-notes>
      <volume>81</volume>
      <issue>2</issue>
      <fpage>36</fpage>
      <lpage>43</lpage>
      <pub-date pub-type="ppub">
        <day>26</day>
        <month>04</month>
        <year>2024</year>
      </pub-date>
      <pub-date pub-type="epub">
        <day>22</day>
        <month>08</month>
        <year>2024</year>
      </pub-date>
      <history>
        <date date-type="received">
          <day>11</day>
          <month>01</month>
          <year>2024</year>
        </date>
        <date date-type="rev-recd">
          <day>09</day>
          <month>02</month>
          <year>2024</year>
        </date>
        <date date-type="accepted">
          <day>09</day>
          <month>02</month>
          <year>2024</year>
        </date>
      </history>
      <permissions>
        <ali:free_to_read xmlns:ali="http://www.niso.org/schemas/ali/1.0/"/>
      </permissions>
      <abstract>
        <p>It was established that the age at first calving of dairy cows, their milk production,</p>
        <p>reproductive traits, duration and efficiency of productive lifespan depend on the growth intensity of</p>
        <p>replacement heifers. Heifers with growth retardation in any period up to 1 year of age are characterized</p>
        <p>by an older age at first calving (by 4.7–7.9% depending on the age at which growth retardation was</p>
        <p>observed), lower live weight in the first year of life (by 4.1–24.4%), first lactation milk production</p>
        <p>(milk yield by 6.1–13.2%, milk fat yield by 7.4–13.1%, milk protein yield by 8.7–17.3%) and lifetime</p>
        <p>milk production (lifetime milk yield by 12.1–25.9%, milk fat + milk protein yields by 13.1–26.3%), as</p>
        <p>well as lower milk yield, milk fat and milk protein per one day of life, productive lifetime and lactation</p>
        <p>(by 8.6–21.1%) compared with animals without growth retardation. Animals with growth retardation</p>
        <p>are inferior to animals without growth retardation on the investigated traits, even after the subsequent</p>
        <p>elimination of retardation.</p>
      </abstract>
      <kwd-group>
        <label>Keywords</label>
        <kwd>dairy cattle</kwd>
        <kwd>growth</kwd>
        <kwd>growth retardation</kwd>
        <kwd>milk production</kwd>
        <kwd>reproductive traits</kwd>
        <kwd>duration and efficiency of productive lifespan</kwd>
      </kwd-group>
    </article-meta>
  </front>
</article>
