<?xml version='1.0' encoding='utf-8'?>
<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:contributor>G.A. Sargeant</dc:contributor>
  <dc:contributor>B.S. Yandell</dc:contributor>
  <dc:contributor>J.J. Parrish</dc:contributor>
  <dc:creator>G.C. Ostermeier</dc:creator>
  <dc:date>2001</dc:date>
  <dc:description>&lt;p&gt;&lt;span&gt;The relationship between sperm nuclear shape and bull fertility was determined. Two groups of bulls, 3 per group, were selected. Bulls differed in fertility based on lifetime nonreturn rates. Digital images of propidium iodide-stained sperm from each bull were collected and shape-evaluated by Fourier harmonic amplitudes 0 to 5. A discriminant function (&lt;/span&gt;&lt;i&gt;P&lt;/i&gt;&lt;span&gt;&amp;nbsp;&amp;lt; .05) was constructed based on harmonic amplitudes and the 2 fertility groups. When individual sperm were classified as being of high or lower fertility, the percentage of each bull's sperm placed in the high-fertility group had a linear relationship (&lt;/span&gt;&lt;i&gt;r&lt;/i&gt;&lt;span&gt;&amp;nbsp;= .89,&amp;nbsp;&lt;/span&gt;&lt;i&gt;P &amp;lt;&lt;/i&gt;&lt;span&gt;&amp;nbsp;.05) with fertility. To construct a plot of mean sperm shapes, a novel technique to automatically orient and identify the anterior tip of the sperm head was developed. The mean nuclear shape of high-fertility sperm was more elongated and tapered than those of lower fertility. A discriminant function (&lt;/span&gt;&lt;i&gt;P&lt;/i&gt;&lt;span&gt;&amp;nbsp;&amp;lt; .05) was also constructed that separated the 6 bulls into 2 groups based only on the harmonic amplitudes or sperm nuclear shape. The bulls were correctly classified into the 2 fertility groups. A comparison of sperm chromatin structure analysis (SCSA) and harmonic amplitudes found that overall size variance, anterior roundness, and posterior taperedness of sperm nuclei were related to chromatin stability (&lt;/span&gt;&lt;i&gt;P&lt;/i&gt;&lt;span&gt;&amp;nbsp;&amp;lt; .05). Some of the differences observed in sperm nuclear shape between the high- and lower-fertility bulls may be explained by varying levels of chromatin stability. However, sperm nuclear shape appears to contain additional information from chromatin stability alone. In this particular study, with 6 bulls, all with good chromatin quality, sperm nuclear shape was a better predictor of bull fertility.&lt;/span&gt;&lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.1002/j.1939-4640.2001.tb02219.x</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>American Society of Andrology</dc:publisher>
  <dc:title>Relationship of bull fertility to sperm nuclear shape</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>