Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2011. / Includes bibliography. / ENGLISH ABSTRACT: A growth and digestibility trial was conducted comparing the effect of an experimental enzyme at
three different inclusions. A negative control containing no enzyme additions and a positive control
containing a proven commercial enzyme were compared in a maize-soybean diet noting the
performance of broilers and the digestibility of the grower feed. The commercial enzyme was a
granular product with a xylanase activity of 38114.29 nkat/g and the second enzyme (ABO374) was a
liquid experimental product with a xylanase activity of 1426.86 nkat/ml. Five diets were used i.e.
control basal diet without enzyme supplementation (negative control), basal diet supplemented with
the commercial enzyme (positive control) and three basal diets supplemented with the test enzyme at
various inclusion levels (ABO 50, ABO 100 and ABO 200). The positive control was supplemented
with 200 g/ton of the commercial enzyme; ABO 50 was supplemented with ABO374 at an inclusion
level of 2671 ml/ton, ABO 100 with 5342 ml/ton and ABO 200 with 10684 ml/ton. Supplementation
with the test enzyme (ABO 50) significantly improved BW at 23 days of age by 4.6 % (1107.4 g vs
960.96 g) and at 37 days of age by 3.2 % (2311.75 g vs 2237.81 g) over the negative control. Body
weight gain for the total period of the trial was significantly improved by 3.24 % (64.32 g/bird/day vs
62.24 g/bird/day) the test enzyme supplementation (ABO 50) when compared to the negative control.
During the starter phase, test enzyme supplementation (ABO 50) led to an improvement of 4.58 %
(1.25 vs 1.31) in FCR in comparison with the negative control. The FCR for the total trial obtained by
the test enzyme supplementation was significantly lower than the FCR obtained by the positive
control. The highest EPER obtained for this trail was by the test enzyme supplemented diets and this
was significantly higher than the EPER obtained by the positive control. It is clear from this growth trial
that the test enzyme (ABO374) at an inclusion level of 2671 ml/ton outperformed the commercial
enzyme and that it has the potential to improve the production performance of broilers on a maizeSBM based diet.
The total tract digestibility method and total collection method was used to conduct the digestibility
trial. The total tract digestibility method measures the difference between the amounts of each nutrient
consumed from the amounts of each nutrient excreted in faeces. Only apparent digestibilities are
reported for the digestibility trial. Apparent digestibility does not take the endogenous protein fraction
in the faeces into account. The endogenous protein fraction is derived from digestive enzymes and
proteins from the intestinal walls that are secreted into the digestive tract. The grower negative
control, positive control, ABO 50, ABO 100 and ABO 200 diets used in the production trial were also
used in the digestibility trial. Supplementation with the test enzyme showed no significant
improvements on the apparent digestibility of dry matter, organic material, ash, crude protein,
metabolisable energy or crude fibre. No significant improvements in the apparent digestibility of the
amino acids (threonine, arginine, valine, lysine, methionine, cysteine and isoleucine) were noticed either and thus the digestibility of the grower feed were not influenced by the addition of enzymes due
to the supplementation of the test enzyme ABO374.
Pelletisation of the grower diets could have lead to the inactivation of the enzyme due to the high
temperature at which pelletisation takes place. Another possible reason why enzyme supplementation
did not increase nutrient digestibility, may be that the breakdown of non-starch polysaccharides by the
enzymes led to an increase in the concentration of oligosaccharides in the small intestine of the birds,
thus leading to the decrease in nutrient absorption
Key words: body weight, body weight gain, feed conversion ratio, European production efficiency
ratio, maize, soybean meal, apparent digestibility, dry matter, organic material, ash, crude protein,
metabolisable energy, crude fibre, xylanase, pellitisation. / AFRIKAANSE OPSOMMING: ‘n Groei en vertering studie was uitgevoer om die effek van ‘n eksperimentele ensiem wat teen drie
verskillende insluitingsvlakke by ‘n basale dieët bygevoeg is te vergelyk met ‘n negatiewe kontrole wat
geen ensiem bevat het nie en met ‘n positiewe kontrole wat ‘n kommersiële ensiem bevat in ‘n mielesojaboon oliekoek dieët op die produksie vermoë van braaikuikens en die verteerbaarheid van die
groei voer. Die kommersiële ensiem was ‘n granulêre produk met ‘n xylanase aktiwiteit van 38114.29
nkat/g en die eksperimentele ensiem (ABO374) was ‘n vloeistof produk met ‘n xylanase aktiwiteit van
1426.86 nkat/ml. Vyf diëte was gebruik nl. ‘n basale dieët met geen ensiem byvoeging (negatiewe
kontrole), basale dieët met die byvoeging van die kommersiële ensiem (positiewe kontrole) en drie
basale diëte wat met die byvoeging van die eksperimentele ensiem teen drie verskillende insluitings
vlakke (ABO 50, ABO 100 and ABO 200). Die kommersiële ensiem was by die positiewe kontrole
bygevoeg met ‘n insluitings vlak van 200 g/ton, ABO374 was bygevoeg by ABO 50 met ‘n insluitings
vlak van 2671 ml/ton, ABO 100 met 5342 ml/ton en ABO 200 met 10684 ml/ton. Die byvoeging van
die eksperimentele ensiem (ABO 50) het gelei tot die betekenisvolle verbetering van die
liggaamsmassa van die voëls by die ouderdom van 23 dae met 4.6 % (1107.4 g teenoor 960.96 g) en
by die ouderdom van 37 dae met 3.2 % (2311.75 g teenoor 2237.81 g) teenoor die negatiewe
kontrole. Liggaams massa toename vir die hele periode van die studie was betekenisvol verhoog met
3.24 % (64.32 g/kuiken/dag teenoor 62.24 g/kuilen/dag) met die byvoeging van die eksperimentele
ensiem (ABO374) teenoor die negatiewe kontrole. Voeromset verhouding was betekenisvol verbeter
met 4.58 % (1.25 teenoor 1.31) toe die kommersiële ensiem bygevoeg was teenoor die negatiewe
kontrole. Die hoogste europese produksie effektiwiteits verhouding wat verkry is vir die hele studie
periode is deur die byvoeging van die eksperimentele ensiem (ABO374). Hierdie groei studie dui dus
duidelik aan dat die gebruik van die eksperimentele ensiem (ABO374) baie beter resultate as die
kommersiële ensiem opgelewer het teen ‘n insluitings vlak van 2671 ml/ton, dus het ABO374 die
potensiaal om die produksie potensiaal van braaikuikens op ‘n mielie-sojaboonoliekoek dieët te
verbeter.
Die totale spysverteringskanaal verteerbaarheid metode was gebruik om die verteerbaarheid studie
uit te voer. Die totale spysverteringskanaal verteerbaarheid metode meet die verskil tussen die
nutriënt inhoud van die voer en die nutriënt inhoud van die mis. Slegs die skynbare verteerbaarheid
van nutriënte word vir hierdie verteerbaarheidstudie gerapporteer. Skynbare verteerbaarheid sluit nie
die endogene proteïenfraksie wat afkomstig is van verteringsensieme of die proteïene afkomstig
vanaf die spysverteringskanaal se intestinale wande af in nie. Die negatiewe kontrole, positiewe
kontrole, ABO 50, ABO 100 en ABO 200 groei diëte gebruik in die produksie studie is gebruik vir die
verteringsstudie. Die byvoeging van die eksperimentele ensiem het geen betekenisvolle resultate
opgelewer ten opsigte van droë materiaal, organiese material, as, ru-proteïen, ru-vesel of
metaboliseerbare energie nie. Daar was ook geen betekenisvolle resultate opgelewer wanneer die
eksperimentele ensiem bygevoeg was nie ten opsigte van die verteerbaarheid vir aminosure
(treonien, arginien, valien, metionien, sisteïen en isoleosien) nie en dus is die verteerbaarheid van die
groeivoer glad nie beïnvloed deur die byvoeging van die eksperimentele ensiem nie. Die verpilling van die groei voer mag dalk gelei het tot die inaktivering van die eksperimentele ensiem
deur dat dit blootgestel was aan hoë temperature. ‘n Ander moontlike rede vir die mislukking van die
ensiem kon gewees het dat die afbreking van die nie-stysel polisakkariedes deur die ensiem kon gelei
het tot die verhoging van die oligosakkariede konsentrasie in die laer spysverterings kanaal en dus
kon dit lei tot ‘n verhoogde deurvloeitempo, gevolg deur ‘n afname in die absorpsie van nutriënte.
Sleutel woorde: Liggaamsmassa, liggaamsmassa toename, voeromsetverhouding Europese
produksie effektiwiteits verhouding, mielie, sojaboonoliekoek, skynbare verteerbaarheid, droëmaterial,
organiesematerial, as, ru-proteïen, ru-vesel, metaboliseerbare energie, verpilling.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/6456 |
| Date | 03 1900 |
| Creators | Botha, Corne J. |
| Contributors | Pieterse, Elsje, University of Stellenbosch. Faculty of AgriSciences. Dept. of Animal Sciences. |
| Publisher | Stellenbosch : University of Stellenbosch |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | Unknown |
| Type | Thesis |
| Format | 62 p. |
| Rights | University of Stellenbosch |
Page generated in 0.0027 seconds