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The effect of liquid rumen-protected lysine supplementation on lactation performance of Holstein cows

Dissertation (MSc(Agric))--University of Pretoria, 2009.

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Other Authors: Erasmus, L.J. (Lourens Jacobus)
Format: Thesis
Published: University of Pretoria 2013
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access_status_str Open Access
author2 Erasmus, L.J. (Lourens Jacobus)
author_browse Erasmus, L.J. (Lourens Jacobus)
author_facet Erasmus, L.J. (Lourens Jacobus)
collection Thesis
dc_rights_str_mv © 2008, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria
description Dissertation (MSc(Agric))--University of Pretoria, 2009.
format Thesis
id oai:repository.up.ac.za:2263/27231
institution University of Pretoria (South Africa)
last_indexed 2026-06-10T12:36:37.921Z
license_str Other — see source repository
provenance_str_mv Harvested via OAI-PMH from UPSpace — University of Pretoria Institutional Repository
publishDate 2013
publishDateRange 2013
publishDateSort 2013
publisher University of Pretoria
publisherStr University of Pretoria
record_format dspace
source_str UPSpace — University of Pretoria Institutional Repository
spelling oai:repository.up.ac.za:2263/27231 The effect of liquid rumen-protected lysine supplementation on lactation performance of Holstein cows Erasmus, L.J. (Lourens Jacobus) richardtv@vitam.co.za Venter, Richardt Holstein cows Liquid Rumen protected Lysine UCTD Dissertation (MSc(Agric))--University of Pretoria, 2009. Thirty high-producing multiparous Holstein cows were used in a completely randomized block design to compare a lysine deficient total mixed ration, which was sufficient in methionine, to the same diet supplemented with a rumen protected lysine product. The CPM-Dairy prediction model was used to estimate the nutrient requirements and adequacy or deficiency of amino acids. During the 21-day prepartum transition period, cows were fed 4 kg (dry basis) of the lysine deficient diet plus Eragrostis curvula hay ad lib. After calving, cows were fed the lysine deficient diet for the first three weeks and were then blocked according to the average production from day 19-21. Fifteen cows were allocated to each treatment and blocked into 15 groups of two each. Data on production parameters were analyzed for all cows and also separately for cows in the 10 highest production blocks. The experimental period was from day 22 to 120 postpartum. Lysine supplementation resulted in an optimal dietary lysine : methionine ratio in metabolisable protein of 7.2 : 2.4. Lysine supplementation did not affect dry matter intake, milk production, milk fat percentage, milk protein percentage, milk urea nitrogen, body weight or body condition score; but decreased the non-casein nitrogen and whey content of milk. Furthermore, milk casein, which is the milk nitrogen fraction most sensitive towards increased duodenal supply of lysine and methionine, was not affected. The rumen protected lysine product evaluated did not improve cow productivity, probably because the product was either unprotected from rumen degradation, or overprotected to the extent that the lysine was not available for absorption in the small intestine; or absorbed but could not be metabolised. Copyright Animal and Wildlife Sciences unrestricted 2013-09-07T10:59:56Z 2009-09-15 2013-09-07T10:59:56Z 2009-04-23 2009-09-15 2009-08-13 Dissertation Venter, R 2008, The effect of liquid rumen-protected lysine supplementation on lactation performance of Holstein cows, MSc(Agric) dissertation, University of Pretoria, Pretoria, viewed yymmdd < http://hdl.handle.net/2263/27231 > E1377/gm http://hdl.handle.net/2263/27231 http://upetd.up.ac.za/thesis/available/etd-08132009-192500/ © 2008, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria application/pdf University of Pretoria
spellingShingle Holstein cows
Liquid
Rumen protected
Lysine
UCTD
The effect of liquid rumen-protected lysine supplementation on lactation performance of Holstein cows
title The effect of liquid rumen-protected lysine supplementation on lactation performance of Holstein cows
title_full The effect of liquid rumen-protected lysine supplementation on lactation performance of Holstein cows
title_fullStr The effect of liquid rumen-protected lysine supplementation on lactation performance of Holstein cows
title_full_unstemmed The effect of liquid rumen-protected lysine supplementation on lactation performance of Holstein cows
title_short The effect of liquid rumen-protected lysine supplementation on lactation performance of Holstein cows
title_sort effect of liquid rumen protected lysine supplementation on lactation performance of holstein cows
topic Holstein cows
Liquid
Rumen protected
Lysine
UCTD
url http://hdl.handle.net/2263/27231
http://upetd.up.ac.za/thesis/available/etd-08132009-192500/