<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html> <head> <title>UTas ePrints - Using lactation curves as a tool for breeding, nutrition and health management decisions in pasture-based dairy systems</title> <script type="text/javascript" src="http://eprints.utas.edu.au/javascript/auto.js"><!-- padder --></script> <style type="text/css" media="screen">@import url(http://eprints.utas.edu.au/style/auto.css);</style> <style type="text/css" media="print">@import url(http://eprints.utas.edu.au/style/print.css);</style> <link rel="icon" href="/images/eprints/favicon.ico" type="image/x-icon" /> <link rel="shortcut icon" href="/images/eprints/favicon.ico" type="image/x-icon" /> <link rel="Top" href="http://eprints.utas.edu.au/" /> <link rel="Search" href="http://eprints.utas.edu.au/cgi/search" /> <meta content="Adediran, S.A." name="eprints.creators_name" /> <meta content="Malau-Aduli, A.E.O." name="eprints.creators_name" /> <meta content="Roche, J.R." name="eprints.creators_name" /> <meta content="Donaghy, D.J." name="eprints.creators_name" /> <meta name="eprints.creators_id" /> <meta content="Aduli.MalauAduli@utas.edu.au" name="eprints.creators_id" /> <meta name="eprints.creators_id" /> <meta name="eprints.creators_id" /> <meta content="conference_item" name="eprints.type" /> <meta content="2008-01-24 00:27:05" name="eprints.datestamp" /> <meta content="2008-01-24T00:57:54Z" name="eprints.lastmod" /> <meta content="show" name="eprints.metadata_visibility" /> <meta content="Using lactation curves as a tool for breeding, nutrition and health management decisions in pasture-based dairy systems" name="eprints.title" /> <meta content="pub" name="eprints.ispublished" /> <meta content="270207" name="eprints.subjects" /> <meta content="300401" name="eprints.subjects" /> <meta content="300400" name="eprints.subjects" /> <meta content="public" name="eprints.full_text_status" /> <meta content="paper" name="eprints.pres_type" /> <meta content="Lactation curves, pasture-based dairy systems, breeding, nutrition, health management" name="eprints.keywords" /> <meta content="In: Bill Fulkerson (Editor) Current Topics in Dairy Production, Volume 12’, Proceedings of the Dairy Research Foundation Symposium, The University of Sydney, Australia, 74-78 (2007)" name="eprints.note" /> <meta content="Milk yield and reproductive efficiency are crucial to profitable dairying. Although, genetic improvement in the last few decades has led to substantial increases in milk yield/cow, fertility and reproductive health have declined (Dematawewa and Berger, 1998). In a pasture-based system, a 365 day calving interval is crucial for optimum profit. Hence the need to increase milk yield by improving persistence of lactation rather than peak lactation which puts increased stress on the cows at the time when they should be rebreeding. Peak milk yield, persistency and lactation length are the key components of the lactation profile. Dairy cows with high peak yields are more prone to metabolic and physiological disorders (Terkeli et al 1999). Although estimated breeding values (EBV) in dairy cows in Australia incorporates indices of economic value, such as survival and milking speed, the impact of the current breeding approach and management on the shape of the lactation profile is not clear. Mathematical functions such as those previously used to describe a series of milk test day records (Wood, 1967, Wilmink, 1987), have the advantage of minimizing random variation while simultaneously summarising the lactation profile into biologically interpretable parameters." name="eprints.abstract" /> <meta content="2007-11-08" name="eprints.date" /> <meta content="published" name="eprints.date_type" /> <meta content="In: Bill Fulkerson (Editor) Current Topics in Dairy Production, Proceedings of the Dairy Research Foundation Symposium, The University of Sydney, Australia." name="eprints.publication" /> <meta content="12" name="eprints.volume" /> <meta content="74-78" name="eprints.pagerange" /> <meta content="Dairy Research Foundation Symposium" name="eprints.event_title" /> <meta content="Sydney" name="eprints.event_location" /> <meta content="8-9 November 2007" name="eprints.event_dates" /> <meta content="conference" name="eprints.event_type" /> <meta content="TRUE" name="eprints.refereed" /> <meta content="1326-849X" name="eprints.issn" /> <meta content="http://www.vetsci.usyd.edu.au/foundations/drf/symposium.shtml" name="eprints.official_url" /> <meta content="Ali, T. E., and Schaeffer, L. R. (1987) Accounting for covariances among test day milk yields in dairy cows. Can. J. An Sci. 67: 637-644. Beever D.E, Rook, A.J, France, J, Danoa, M.S and Gill, M. (1991). A review of empirical and mechanistic models of lactation performance by the dairy cow. Livest Prod. Sci., 29: 115-130. Dematawewa, C.M.B., Berger, PJ. (1998). Genetic and phenotypic parameter for 305-day yield, fertility and survival in Hosteins. J. Dairy Sci. 81, 2700-2709. Dijkstra, J, France, J, Dhanoa, M.S, Maas, J.A, Hanigan, M.D, Rook, A.S and Beever, D.E. (1997). A model to describe growth patterns of the mammary gland during pregnancy and lactation. J. Dairy Sci. 80:2340–2354. Ferguson J. D., and Boston, R. (1993) Lactation curves analysis: Comparison of gamma function, polynomial and exponential methods towards a mechanistic model of milk production. J. Dairy Sci. 76 (Suppl. 1): 268. (Abstr.) Garcia, S.C and Holmes, C.W. (2001). Lactation curves of autumn- and spring-calved cows in pasture-based dairy systems. Livest. Prod. Sci. 68: 189-203. Guo, Z., and Swalve, H. H. (1995) Modelling of the lactation curve as a sub-model in the evaluation of test day records. Paper presented at the INTERBULL open meeting, 7-8 September, 1995, Prague, Czech Republic. Jenkins, T. G., and Ferrell, C. L. (1984) A note on lactation curves of crossbred cows. Anim. Prod. 39: 470-482. Olori, V. E., S. Brotherstone, et al. (1999). Fit of standard models of the lactation curve to weekly records of milk production of cows in a single herd. Livest. Prod. Sci. 58(1). Roche, J. R., Berry, D.P. and Kolver, E.S. (2006). Holstein-Friesian Strain and Feed Effects on Milk Production, Bodyweight and Body Condition Score Profiles in Grazing Dairy Cows J. Dairy Sci. 89: 3532–3543. SAS Institute Inc. (2003) SAS User’s Guide: Statistics. Version 9.1 Edition. SAS Institute Inc.: Cary, NC. Sherchand, L., R. W. McNew, D. W. Kellog, and Z. B. Johnson (1995).Selection of a mathematical model to generate lactation curves using daily milk yields of Holstein cows. J. Dairy Sci. 78:2507–2513 Terkeli, M., Akinchi, Z. Dogan I., and Akcan A. (2000). Factors affecting the shape of Lactation Curves of Holstein Cows from the Balikesir Province of Turkey. J. Dairy Sci 83:1381–1386 1381 Tozer, P.R; Huffaker; R.G; 1999: Mathematical equations to describe lactation curves for Holstein-Friesian cows in New South Wales. Aust.J. Agric. Res. 50:431-440 Wilmink, J. B. M. (1987) Adjustment of test-day milk, fat and protein yield for age, season and stage of lactation. Livestock Prod. Sci. 16: 335-348. Wood, P. D. P. (1967). Algebraic model of the lactation curve in cattle.Nature 216, 164.5. " name="eprints.referencetext" /> <meta content="Adediran, S.A. and Malau-Aduli, A.E.O. and Roche, J.R. and Donaghy, D.J. (2007) Using lactation curves as a tool for breeding, nutrition and health management decisions in pasture-based dairy systems. In: Dairy Research Foundation Symposium, 8-9 November 2007, Sydney." name="eprints.citation" /> <meta content="http://eprints.utas.edu.au/2966/1/Malau-Aduli_2007DRFSydney.pdf" name="eprints.document_url" /> <link rel="schema.DC" href="http://purl.org/DC/elements/1.0/" /> <meta content="Using lactation curves as a tool for breeding, nutrition and health management decisions in pasture-based dairy systems" name="DC.title" /> <meta content="Adediran, S.A." name="DC.creator" /> <meta content="Malau-Aduli, A.E.O." name="DC.creator" /> <meta content="Roche, J.R." name="DC.creator" /> <meta content="Donaghy, D.J." name="DC.creator" /> <meta content="270207 Quantitative Genetics" name="DC.subject" /> <meta content="300401 Animal Breeding" name="DC.subject" /> <meta content="300400 Animal Production" name="DC.subject" /> <meta content="Milk yield and reproductive efficiency are crucial to profitable dairying. Although, genetic improvement in the last few decades has led to substantial increases in milk yield/cow, fertility and reproductive health have declined (Dematawewa and Berger, 1998). In a pasture-based system, a 365 day calving interval is crucial for optimum profit. Hence the need to increase milk yield by improving persistence of lactation rather than peak lactation which puts increased stress on the cows at the time when they should be rebreeding. Peak milk yield, persistency and lactation length are the key components of the lactation profile. Dairy cows with high peak yields are more prone to metabolic and physiological disorders (Terkeli et al 1999). Although estimated breeding values (EBV) in dairy cows in Australia incorporates indices of economic value, such as survival and milking speed, the impact of the current breeding approach and management on the shape of the lactation profile is not clear. Mathematical functions such as those previously used to describe a series of milk test day records (Wood, 1967, Wilmink, 1987), have the advantage of minimizing random variation while simultaneously summarising the lactation profile into biologically interpretable parameters." name="DC.description" /> <meta content="2007-11-08" name="DC.date" /> <meta content="Conference or Workshop Item" name="DC.type" /> <meta content="PeerReviewed" name="DC.type" /> <meta content="application/pdf" name="DC.format" /> <meta content="http://eprints.utas.edu.au/2966/1/Malau-Aduli_2007DRFSydney.pdf" name="DC.identifier" /> <meta content="http://www.vetsci.usyd.edu.au/foundations/drf/symposium.shtml" name="DC.relation" /> <meta content="Adediran, S.A. and Malau-Aduli, A.E.O. and Roche, J.R. and Donaghy, D.J. (2007) Using lactation curves as a tool for breeding, nutrition and health management decisions in pasture-based dairy systems. 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border: solid 1px #ccc; padding: 3px"><tr> <td align="left"><a href="http://eprints.utas.edu.au/cgi/users/home">Login</a> | <a href="http://eprints.utas.edu.au/cgi/register">Create Account</a></td> <td align="right" style="white-space: nowrap"> <form method="get" accept-charset="utf-8" action="http://eprints.utas.edu.au/cgi/search" style="display:inline"> <input class="ep_tm_searchbarbox" size="20" type="text" name="q" /> <input class="ep_tm_searchbarbutton" value="Search" type="submit" name="_action_search" /> <input type="hidden" name="_order" value="bytitle" /> <input type="hidden" name="basic_srchtype" value="ALL" /> <input type="hidden" name="_satisfyall" value="ALL" /> </form> </td> </tr></table></td></tr> <tr> <td class="toplinks"><!-- InstanceBeginEditable name="content" --> <div align="center"> <table width="720" class="ep_tm_main"><tr><td align="left"> <h1 class="ep_tm_pagetitle">Using lactation curves as a tool for breeding, nutrition and health management decisions in pasture-based dairy systems</h1> <p style="margin-bottom: 1em" class="not_ep_block"><span class="person_name">Adediran, S.A.</span> and <span class="person_name">Malau-Aduli, A.E.O.</span> and <span class="person_name">Roche, J.R.</span> and <span class="person_name">Donaghy, D.J.</span> (2007) <xhtml:em>Using lactation curves as a tool for breeding, nutrition and health management decisions in pasture-based dairy systems.</xhtml:em> In: Dairy Research Foundation Symposium, 8-9 November 2007, Sydney.</p><p style="margin-bottom: 1em" class="not_ep_block"></p><table style="margin-bottom: 1em" class="not_ep_block"><tr><td valign="top" style="text-align:center"><a onmouseover="EPJS_ShowPreview( event, 'doc_preview_3991' );" href="http://eprints.utas.edu.au/2966/1/Malau-Aduli_2007DRFSydney.pdf" onmouseout="EPJS_HidePreview( event, 'doc_preview_3991' );"><img alt="[img]" src="http://eprints.utas.edu.au/style/images/fileicons/application_pdf.png" class="ep_doc_icon" border="0" /></a><div class="ep_preview" id="doc_preview_3991"><table><tr><td><img alt="" src="http://eprints.utas.edu.au/2966/thumbnails/1/preview.png" class="ep_preview_image" border="0" /><div class="ep_preview_title">Preview</div></td></tr></table></div></td><td valign="top"><a href="http://eprints.utas.edu.au/2966/1/Malau-Aduli_2007DRFSydney.pdf"><span class="ep_document_citation">PDF</span></a> - Requires a PDF viewer<br />122Kb</td></tr></table><p style="margin-bottom: 1em" class="not_ep_block">Official URL: <a href="http://www.vetsci.usyd.edu.au/foundations/drf/symposium.shtml">http://www.vetsci.usyd.edu.au/foundations/drf/symposium.shtml</a></p><div class="not_ep_block"><h2>Abstract</h2><p style="padding-bottom: 16px; text-align: left; margin: 1em auto 0em auto">Milk yield and reproductive efficiency are crucial to profitable dairying. Although, genetic improvement in the last few decades has led to substantial increases in milk yield/cow, fertility and reproductive health have declined (Dematawewa and Berger, 1998). In a pasture-based system, a 365 day calving interval is crucial for optimum profit. Hence the need to increase milk yield by improving persistence of lactation rather than peak lactation which puts increased stress on the cows at the time when they should be rebreeding. Peak milk yield, persistency and lactation length are the key components of the lactation profile. Dairy cows with high peak yields are more prone to metabolic and physiological disorders (Terkeli et al 1999). Although estimated breeding values (EBV) in dairy cows in Australia incorporates indices of economic value, such as survival and milking speed, the impact of the current breeding approach and management on the shape of the lactation profile is not clear. Mathematical functions such as those previously used to describe a series of milk test day records (Wood, 1967, Wilmink, 1987), have the advantage of minimizing random variation while simultaneously summarising the lactation profile into biologically interpretable parameters.</p></div><table style="margin-bottom: 1em" cellpadding="3" class="not_ep_block" border="0"><tr><th valign="top" class="ep_row">Item Type:</th><td valign="top" class="ep_row">Conference or Workshop Item (Paper)</td></tr><tr><th valign="top" class="ep_row">Additional Information:</th><td valign="top" class="ep_row">In: Bill Fulkerson (Editor) Current Topics in Dairy Production, Volume 12’, Proceedings of the Dairy Research Foundation Symposium, The University of Sydney, Australia, 74-78 (2007)</td></tr><tr><th valign="top" class="ep_row">Keywords:</th><td valign="top" class="ep_row">Lactation curves, pasture-based dairy systems, breeding, nutrition, health management</td></tr><tr><th valign="top" class="ep_row">Subjects:</th><td valign="top" class="ep_row"><a href="http://eprints.utas.edu.au/view/subjects/270207.html">270000 Biological Sciences > 270200 Genetics > 270207 Quantitative Genetics</a><br /><a href="http://eprints.utas.edu.au/view/subjects/300401.html">300000 Agricultural, Veterinary and Environmental Sciences > 300400 Animal Production > 300401 Animal Breeding</a><br /><a href="http://eprints.utas.edu.au/view/subjects/300400.html">300000 Agricultural, Veterinary and Environmental Sciences > 300400 Animal Production</a></td></tr><tr><th valign="top" class="ep_row">Collections:</th><td valign="top" class="ep_row">UNSPECIFIED</td></tr><tr><th valign="top" class="ep_row">ID Code:</th><td valign="top" class="ep_row">2966</td></tr><tr><th valign="top" class="ep_row">Deposited By:</th><td valign="top" class="ep_row"><span class="ep_name_citation"><span class="person_name">Dr Aduli E.O. Malau-Aduli</span></span></td></tr><tr><th valign="top" class="ep_row">Deposited On:</th><td valign="top" class="ep_row">24 Jan 2008 11:27</td></tr><tr><th valign="top" class="ep_row">Last Modified:</th><td valign="top" class="ep_row">24 Jan 2008 11:57</td></tr><tr><th valign="top" class="ep_row">ePrint Statistics:</th><td valign="top" class="ep_row"><a target="ePrintStats" href="/es/index.php?action=show_detail_eprint;id=2966;">View statistics for this ePrint</a></td></tr></table><p align="right">Repository Staff Only: <a href="http://eprints.utas.edu.au/cgi/users/home?screen=EPrint::View&eprintid=2966">item control page</a></p> </td></tr></table> </div> <!-- InstanceEndEditable --></td> </tr> <tr> <td><!-- #BeginLibraryItem "/Library/footer_eprints.lbi" --> <table width="795" border="0" align="left" cellpadding="0" class="footer"> <tr valign="top"> <td colspan="2"><div align="center"><a href="http://www.utas.edu.au">UTAS home</a> | <a href="http://www.utas.edu.au/library/">Library home</a> | <a href="/">ePrints home</a> | <a href="/contact.html">contact</a> | <a href="/information.html">about</a> | <a href="/view/">browse</a> | <a href="/perl/search/simple">search</a> | <a href="/perl/register">register</a> | <a href="/perl/users/home">user area</a> | <a href="/help/">help</a></div><br /></td> </tr> <tr><td colspan="2"><p><img src="/images/eprints/footerline.gif" width="100%" height="4" /></p></td></tr> <tr valign="top"> <td width="68%" class="footer">Authorised by the University Librarian<br /> © University of Tasmania ABN 30 764 374 782<br /> <a href="http://www.utas.edu.au/cricos/">CRICOS Provider Code 00586B</a> | <a href="http://www.utas.edu.au/copyright/copyright_disclaimers.html">Copyright & Disclaimers</a> | <a href="http://www.utas.edu.au/accessibility/index.html">Accessibility</a> | <a href="http://eprints.utas.edu.au/feedback/">Site Feedback</a> </td> <td width="32%"><div align="right"> <p align="right" class="NoPrint"><a href="http://www.utas.edu.au/"><img src="http://www.utas.edu.au/shared/logos/unioftasstrip.gif" alt="University of Tasmania Home Page" width="260" height="16" border="0" align="right" /></a></p> <p align="right" class="NoPrint"><a href="http://www.utas.edu.au/"><br /> </a></p> </div></td> </tr> <tr valign="top"> <td><p> </p></td> <td><div align="right"><span class="NoPrint"><a href="http://www.eprints.org/software/"><img src="/images/eprintslogo.gif" alt="ePrints logo" width="77" height="29" border="0" align="bottom" /></a></span></div></td> </tr> </table> <!-- #EndLibraryItem --> <div align="center"></div></td> </tr> </table> </body> </html>