Thesis (MPhil)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: CPM Dairy was developed to maintain amino acid balance. because the correct amino
acid relationship has an influence on milk production and milk composition (Schwab e/
af. 1992, Rulquin e/ af. 1993). Rulquin e/ af. (1993) found that an increase in lysine and
methionine concentration in the diet had no meaningful effect on milk production and
milkfat production. However, milk protein production is described as a function of
lysine and methionine concentration.
In order to balance the amino acid relationships, the CNCPS model has been adopted,
using the following guidelines:
I. a dairy cow feed characteristic scheme, described by Van Soest e/ af. (1991) and
Sniffen e/ aI. (1992),
II. a model for rumen fermentation and bacterial growth in the dairy cow, described
by Russel e/ af. (1992),
Ill. feed val ues for dairy cow feeds, described by Sniffen e/ af. (1992).
IV. a set of formulas describing the feeding needs of dairy cows under different
circumstances, assembled by Fox e/ af. (1992).
Bateman e/ af. (2001) studied the accuracy of formulation models according to crude
protein (CP) and amino acid (AA)-flow to the duodenum in lactating dairy cow diets.
CPM Dairy does not calculate direct flow of CP to the duodenum, but the following
adjustment was made: the change-over of metabolizable protein (MP) to CP is done by
increasing bacterial protein from 60% to 100% of bacterial-CP. Intestinal digestion of
fraction B3-protein is increased from 80% to 100%, whereas fraction C-protein is
increased from 0 to 100% to change feed-MP to feed-CP. CP from feed and microbes
are summed to indicate total CP-flow to the duodenum.
AA-flow, as calculated by CPM Dairy, is used without adjustments.
A rise in MUN-Ievels are typical to spring and summer months. which can be ascribed to
high soluble protein and low soluble carbohydrates in grasses and legumes. This gives
rise to an excess N-uptake in the bloodstream. Grass silage, when fed as primary feeding source. has the same reaction. Blood-urea-nitrogen (BUN) is the amount of urea-N
found in the blood of the cow. MUN is the fraction ofN in the milk in the form of urea.
MUN is normally 85% the concentration of BUN. Studies show that an increase in
BUN/MUN levels leads to a negative effect on the reproductive ability of the cow. An
increase in BUN-levels leads to an increase in urea in the reproductive tract of the animal.
Urea passes between the blood plasma and the reproductive tract. It is therefore obvious
that a high BUN-concentration leads to high levels of urea in the reproductive tract.
In order to eradicate this problem. the use of deodorise in the supplemental feed of the
lactating dairy cow \vas recommended.
Deodorise is a natural product manufactured by Alltech. The product is derived from the
Yuccha Schidigera plant. Two glycocomponents (CI and C II) of this plant binds gasses
such as N1-I3. (Alltech information sheet)
During .June to August 2002 data were collected regarding the effect of deodorise on
lactating dairy cows.
No meaningful difference between the two groups in this experiment was found. / AFRIKAANSE OPSOMMING: CPM Dairy is ontwikkel am aminosuurbalans te handhaaC aangesien die korrekte
aminosuurvcrhoudings 'n invloed op melkproduksie en mclksamcstelling het. (Schwab el
al. 1992, Rulquin el al. 1993). Rulquin el al. (1993) hct gcvind dat 'n tacname in die
konsentrasic van lisien en mctionien in dic rantsoen gccn nocmenswaardigc cffek op
melkproduksie en meIkvctproduksie het nie. MelkproteYcnproduksie word cgtcr beskryf
as 'n funksie van !isien- cn metionienkonscntrasie.
Ten einde die aminosuurvcrhoudings te balanseer. is die CNCPS model aangcneem. wat
die volgcndc riglyne gebruik :
I. 'n Melkbees vocdingskarakteriseringskema, soos bcskryf deur Van Soest el 01.
(1991) en Sniffen el 01. (1992).
II. 'n Model van rumcnfermentasie en bakteriele groei in die melkbces, soos deur
Russel e/al. (1992) beskryf.
Ill. Voedingswaardes vir melkbeesvoedingstowwe, soos bcskryf deur Sniffen e/ 01.
( 1992).
IV. 'n Stcl vergelykings wat die voedingsbehoeftcs van mclkbcestc onder
vcrskillende omstandighede beskryf, saamgestel deur Fox e/ 01. (1992).
Bateman e/ 01. (200 I) bestudeer die akkuraatheid van formulasiemodelle ten opsigte van
RP- en aminosuur (AA)-vloei na die duodenum in lakterende melkkoeirantsacne.
CPM Dairy bcreken nie dirckte vloei van RP na die elunderm nie. elus is dic volgenele
aanpassing gcmaak : Die omskakeling van Metaboliseerbare proteYen (MP) na RP word
gedoen deur bakteriele prote"len te verhoog vanaf 60% tot 100% van baktcriCle-RP.
Dermkanaalvertering van ti'aksie B3 proteYen is verhoog vanaf 80% tot IOO(/j), terwyl
fraksie C protc'len vanaf 0 tot 100% verhoog is ten einde voer-M P om te skakcl na voer-
RP. RP vanafvoer en mikrobes word gesommeer en verskafvoorspellings vir totale RPvioei
na dic duodenum.
Die AA-vloei. so os deur CPM Dairy bereken word, is sonder wysigings gebruik. n Styging in MUN-vlakke word tipies in die lente- en somermaande ondervincL wat
toegeskryl' kan word aan hoc oplosbare protc"ien en lae oplosbare koolhidrate in grasse en
peulgewasse. Dit gee aanleiding tot 'n oonnaat N wat in die bloedstroom opgeneem
word. Graskuilvoer, wanneer gevoer word as die primcre voedingsbron, het dieselfde
uitwerking. Bloed-ureumstikstof (BUN) is die hoeveelheid ureum-N teenwoordiu: in die
bloed van die koei. MUN is die fraksie N in melk in die vonn van ureum. MUN is
gewoonlik 85% van die konsentrasie van BUN. Navorsing toon dat 'n toe name in
BUN/MUN vlakke 'n nadelige uitwerking het op die reproduktiewe vermoc van die koei.
'n Toename in BUN-vlakke veroorsaak 'n toename in ureum in die dier se
reproduksiekanaal. Ureum beweeg tussen die plasma en die reproduksiekanaal. Dit is
dus duidelik dat 'n hoc BUN-konsentrasie sal lei tot hoc vlakke van ureum in die
reprod uksiekanaal.
Ten einde hierdie probleem uit te wis, is die gebruik van De-Odorase in die kragvoer van
die lakterende koeie aanbeveel.
De-Odorase is 'n natuurlike produk wat deur Alltech vervaardig word. Die produk is
at1(omstig van die Yucca schidigera plant. Twee glikokomponente (CI en CII) van
hierdie plant bind gasse so os Nl-h (Alltech inligtingstuk).
Gedurende .Iunie tot Augustus 2002 is data ingesamel aangaande die uitwerking van De-
Odorase op melkbeeste.
Daar is geen betekenisvolle verskil tussen die twee groepe met hierdie ekspcriment
waargeneem nle.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/17253 |
| Date | 04 1900 |
| Creators | Vermaak, Jacobus Vermaak |
| Contributors | Cruywagen, C.W., Stellenbosch University. Faculty of Agrisciences. Dept. of Animal Sciences. |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | Afrikaans |
| Detected Language | Unknown |
| Type | Thesis |
| Format | 57 leaves : ill. |
| Rights | Stellenbosch University |
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