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Fermentation, stability and degradability of whole-crop oat silage ensiled with a commercial inoculantPienaar, Johanni 03 1900 (has links)
Thesis (MScAgric (Animal Sciences))--Stellenbosch University, 2010. / ENGLISH ABSTRACT: South Africa is well-known for periodic dry periods and uncertain rainfall. Ensiling of
crops is a method of preserving forage and ensures feed availability during periods when
the supply of good quality forage is low. Cereal-based silages, especially in the Western
Cape, South Africa, represent a significant proportion of feed consumed by ruminant
animals, particularly high-producyion dairy cattle. However, farmers are still concerned
about the technical challenges of ensiling cereal crops. Previous research done on lactic
acid bacteria (LAB) inoculants used on cereal based silage has indicated a potential for
improving silage fermentation, stability and degradability, thus enhancing feed
conversion and production by ruminants.
Two experiments were conducted to determine the effects of inoculating whole-crop oat
silage with Lalsil® Cereal Lactobacilli (Lactobacillus buchneri (NCIMB 40788) and
Pediococcus acidilactici (CNCM MA 18/5M)) LAB on
(1) silage fermentation,
(2) aerobic stability and
(3) nutritional value of silage ensiled under
a. micro-silos conditions and
b. in a bunker under outdoor conditions of a Mediterranean summer. Oats (Avena sativa, cv SSH 405) were planted on 60 ha under dryland conditions at
Elsenburg in the Western Cape province, South Africa. Whole-crop oats were harvested
at the soft dough stage and length of the chopped material was 9 mm (Day of ensiling –
Day 0).
Chopped whole-crop oats were sampled, mixed thoroughly and divided into two portions.
The Inoculant (Lalsil® Cereal) was applied to one portion to provide 5.79 x 109 colony
forming units (CFU) of LAB per gram of fresh material. In the first experiment twenty -
four glass silos (1.5 L glass jars) (WECK, GmbH u.Co., Wehr-Ofligen, W. Germany)
were filled for each of the control and inoculant treatments. The glass silos were stored
in a dark room in the laboratory at ambient temperature. Three glass silos were opened
for each treatment on days 1, 2, 4, 8, 15, 30, 60 and 102 post-ensiling to determine
fermentation dynamics.
A parallel study was done with the same chopped whole-crop oats using the buried bag
technique in a bunker silo. Whole-crop oats were ensiled in six net bags per treatment
buried in a bunker filled with the same untreated whole crop oats. Bags, attached with
nylon lines (3 m lengths) for easy retrieval were buried at 1m and 2 m depths in the same
bunker. The net bags in the bunker were retrieved after 186 days of ensiling.
Dry matter (DM), organic matter (OM), neutral detergent fibre (NDF), crude protein
(CP), lactic acid levels, pH, water soluble carbohydrates (WSC) and in vitro organic
matter degradability (IVOMD) for both studies were determined. Silage of both
experiments was exposed to aerobic conditions for ten days to determine aerobic
stability. It is concluded that the inoculant Lalsil® Cereal had the effect of reducing the
rate of consumption of WSC during the anaerobic phase and aerobic exposure for both experiments. Silage spoilage due to yeasts and moulds was however more evident with
the inoculated silage due the presence of sugars in the micro-silos experiment. / AFRIKAANSE OPSOMMING: Suid-Afrika is bekend vir droë periodes en wisselvallige reënval. Die inkuiling van
gewasse is ‘n goeie manier om ruvoer te voorsien in tye van droogtes of tekorte.
Kleingraan kuilvoer is veral bekend in die Wes-Kaap, Suid-Afrika en maak ‘n groot deel
uit van die melkkoei se rantsoen. Landbouers is nog steeds bekommerd oor die tegniese
aspekte wanneer dit kom by die inkuil van gewasse. Vorige navorsing het getoon dat die
gebruik van ‘n melksuurbakteriese inokulant saam met die inkuiling van gewasse
moontlik die potensiaal het om fermentasie, stabiliteit en degradering te verbeter en
sodoende voeromset te verbeter.
Twee eksperimente is uitgevoer om die effek van die inkuiling van hawerkuilvoer met
Lalsil® Cereal Lactobacilli (Lactobacillus buchneri (NCIMB 40788) en Pediococcus
acidilactici (CNCM MA 18/5M)) LAB te bepaal op
(1) kuilvoer fermentasie,
(2) aërobiese stabiliteit en
(3) nutriëntwaarde van die kuilvoer ingekuil in
a. mikrosilo’s en
b. in ‘n bunker in die buitelug. Hawer (Avena sativa, cv SSH 405) is op 60 ha droë land geplant op Elsenburg in die
Wes-Kaap, Suid-Afrika. Die hawer is ingekuil tydens die sagte deeg stadium en die
gekapte materiaal was ongeveer 9 mm lank.
Gekapte material was deeglik gemeng en in twee gedeel. Die inokulant (Lalsil® Cereal)
is op die een gedeelte gesproei om 5.79 x 109 kolonie-vormende eenhede (KVE)
melksuurbakterieë per gram vars materiaal te voorsien. Tydens die eerste eksperiment is
24 mikrosilo’s (1.5 L glas silo) (WECK, GmbH u.Co., Wehr-Ofligen, W. Duitsland) vir
elke behandeling vol kuilvoer gemaak. Hierdie mikrosilo’s is gestoor in ‘n donker kamer
teen kamertemperatuur. Drie mikrosilo’s is per behandeling oopgemaak op dag 1, 4, 8,
15, 30, 60 en 102 na inkuiling om die fermentasie-dinamika te bepaal.
‘n Parallelle studie is gedoen met dieselfde materiaal ingekuil in netsakke binne die
bunker. Die materiaal was ingekuil in ses netsakke vir elke behandeling. Nylon toue (3
m) is aan die sakke vasgemaak om die uithaal daarvan op latere stadium te vergemaklik.
Hierdie sakke is ingekuil op verskillende dieptes, 1 m en 2 m in dieselfde bunker. Die
sakke is na 186 dae weer uitgehaal.
Droë materiaal (DM), organiese materiaal (OM), neutraal bestande vesel (NBV),
ruproteïen (RP), melksuurvlakke, pH, water oplosbare koolhidrate (WOK) en in vitro
organiese materiaal verteerbaarheid (IVOMV) vir beide studies is bepaal. Kuilvoer van
beide eksperimente is ook blootgestel aan aërobiese toestande vir 10 dae aan aërobiese
toestande blootgestel om aërobiese stabiliteit te bepaal. Daar is bepaal dat die inokulant
Lalsil® Cereal het die tempo van WOK verbruik verminder gedurende die anaërobies
fase sowel as die aërobiese fase vir beide eksperimente. Kuilvoer wat bederf het as gevolg van giste en swamme was meer sigbaar by die inokulant behandelde kuilvoer as
gevolg van die teenwoordigheid van suikers in die mikrosilo’s.
(Sleutelwoorde: hawerkuilvoer, inokulant, mikrosilo’s, water oplosbare koolhidrate
(WOK), in vitro organiese materiaal verteerbaarheid (IVOMV))
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Breed, transport and lairage effects on animal welfare and quality of Namibian beefLuhl, Juljane 03 1900 (has links)
Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: Namibia by nature is very well suited for livestock production and is a net exporter of beef. Beef is currently
exported to South Africa, the European Union (EU) and Japan while market access to the United States of
America is being explored. Food safety, traceability and lately animal welfare are all aspects which are
requested by Namibians trading partners when exporting meat to those countries. The first two aspects have
been addressed with the introduction of the Farm Assured Namibian Beef scheme (FAN Meat) which also
provides basic guidelines for animal welfare.
Beef in Namibia is produced from extensively managed enterprises which are privately owned and
managed, or state owned and communally utilized. The events of handling and transport are considered
stressful to all animals but especially so to extensively raised animals and their reaction to these events has
the potential to severely infringe on their welfare. The aim of this study was to determine the effect of pre-,
during, and post-transportation handling on animal welfare status under Namibian transport conditions. The
study also investigated the influence of breed on the meat quality of Namibian beef.
The level of bruising recorded on slaughter was used to measure animal welfare. Interviews with
producers were conducted to describe the pre-transport handling. Questionnaires that included variables
considered as important indicators of animal welfare during transport were distributed to truck drivers.
Observations of the off-loading event and animal behaviour were completed in lairage at the export abattoir
in Windhoek. The variables that were identified as high risk factors and had a significant influence on the
level of bruising under Namibian transport conditions include animal factors (i.e. breed type, age, sex,
condition and subcutaneous fat cover), pre-transport handling (i.e. re-branding of animals), transport related
risks (loading density and animals lying down during transit) as well as lairage factors (i.e. fit of truck floor to
off-loading ramp, the way animals moved to holding pens, pen size and minimum environmental
temperatures).
The influence of breed on meat tenderness and water-holding capacity of the Longissimus dorsi
muscle of the four main beef breeds (i.e. Brahman, Bonsmara, Simbrah and Simmental), as well as the
effect of different aging periods on meat quality (i.e. 2, 9, 16, 23, 30 & 37 days post mortem) were
investigated. The Brahman differed significantly (p < 0.05) from the other three breeds in terms of all aging
treatments; with higher Warner-Bratzler shear force values reported for this breed. Interactions between days
post mortem and breed were found for the Simbrah, and Simmental breeds, which may be indicative of a
delayed response to aging of meat samples obtained from Simbrah animals. This can possibly be ascribed
to an increased calpastatin activity in these animals. Meat samples obtained from the Bonsmara steers
showed the highest rate of tenderization, with this effect retained until day 30 post mortem.
Recommendations as pertaining to the ante mortem handling of cattle are made. / AFRIKAANSE OPSOMMING: Namibië word gekenmerk deur toestande wat uitstekend vir diereproduksie is, met die land wat as ‘n netto
uitvoerder van beesvleis beskou word. Vleis word na Suid-Afrika, die Europese Unie (EU) en Japan
uitgevoer, met die moontlikheid van die Verenigde State van Amerika wat as ‘n uitvoermark ondersoek word.
Voedselveiligheid, naspeurbaarheid en dierewelsyn is drie vereistes wat deur die invoerders van Namibiese
vleis daargestel word. Die eerste twee vereistes is reeds deur die implementering van die Farm Assured
Namibian beesvleis skema (FAN Meat) aangespreek, met die skema wat basiese riglyne vir dierewelsyn
voorskryf.
Namibiese beesvleis word geproduseer onder grootskaalse ekstensiewe boerdery omstandighede,
wat of privaat besit en bestuur word, of aan die regering behoort en deur plaaslike gemeenskappe benut
word. Die invloed van hantering en vervoer is besonder stresvol vir diere en in besonder vir diere wat onder
ekstensiewe omstandighede geproduseer word. Omdat diere onder ekstensiewe omstandighede
ongewoond aan hantering en vervoer is, kan dié twee aksies ‘n ernstige impak op die welsyn van sulke diere
hê. Die doelwit van die studie was om die invloed van hantering voor-, tydens en na-vervoer onder
Namibiese vervoertoestande te ondersoek. Die invloed van ras op Namibiese beesvleiskwaliteit is ook
ondersoek.
Die mate van kneusing waargeneem met slagting was as standaard gebruik om die welsynstatus
van diere te bepaal. Onderhoude is met produsente gevoer om inligting oor die pre-vervoer toestande in te
win. Vraelyste wat veranderlikes wat as belangrike indikators van dierewelsyn tydens vervoer beskou kan
word, ingesluit het, is aan vragmotorbestuurders versprei. Waarnemings van die aflaai en verwante
diergedrag was by die houfasiliteite van die uitvoer abattoir in Windhoek, waarnatoe die diere vervoer is,
gedoen. Verskeie hoë risiko faktore wat ‘n betekenisvolle invloed op die mate van kneusing wat tydens
vervoer opgedoen is, gehad het, is in die studie geïdentifiseer. Hierdie faktore het dierverwante eienskappe
(d.i. ras, ouderdom, geslag, liggaamskondisie en onderhuidse vetvoorsiening), voorvervoer hantering (d.i.
herbrandmerk van diere), vervoerverwante risiko’s (d.i. aantal diere per trok kompartement en diere wat
tydens vervoer gaan lê), asook ontwerp van houfasiliteite (d.i. verbinding tussen trokvloer en laaibrug, die
manier wat diere na houkampies beweeg het, grootte van houkampies en lae omgewingstemperature),
ingesluit.
Die invloed van ras op die sagtheid en waterhouvermoë van die Longissimus dorsi spier van die vier
hoof vleisbeesrasse (d.i. Brahman, Bonsmara, Simbrah en Simmentaler), asook verskillende
verouderingstydperke op vleiskwaliteit (d.i. 2, 9, 16, 23, 30 en 37 dae post mortem) van die vier rasse is
ondersoek. Die Brahman het betekenisvol (p < 0.05) van die ander drie rasse in terme van die effek van
veroudering op vleiskwaliteit verskil, met hoë Warner-Bratzler skeursterkte waardes wat vir dié ras
aangeteken is. ‘n Interaksie tussen aantal dae post mortem en ras is gevind vir die Simbrah en Simmentaler
rasse, wat dui op ‘n vertraagde effek van vleisveroudering vir die Simbrah ras, moontlik as gevolg van ‘n
hoër mate van kalpastatien aktiwiteit. Vleismonsters bekom van jong Bonsmara bulle het die grootste mate van versagting getoon, met die voordeel wat waargeneem is tot dag 30 van die post mortem
vleisveroudering.
Aanbevelings betreffende die voorslag hantering van beeste word gemaak.
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The effect of different levels of supplementary feed on the production of finisher ostriches (Struthio camelus) grazing irrigated lucerne (Medicago sativa) pasturesStrydom, Marline 12 1900 (has links)
Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: The purpose of this study was to evaluate the production of slaughter ostriches in a grazing environment at
different levels of supplementary feed.
Two grazing trials were conducted. In the first trial, one group of finisher ostriches (six months old) was put into
a feedlot and received a complete finisher diet. The other four groups were allowed to graze lucerne pasture
(stocking rate of 15 birds/ha) with 1500, 1000, 500, and 0g supplementary feed/bird/day. Pasture production
and intake were measured. There was no difference (P >0.05) between the end mean live weights of the feedlot
ostriches and those two grazing groups receiving 1500 or 1000g supplementation. The average daily gain
(ADG) of the group receiving 1000g supplementation was lower (P <0.05) than the ADG of the group receiving
1500g supplementation, but all three groups reached a mean target slaughter weight of 95kg within the 154 days
of the study. Therefore, pastures together with the correct supplementation (at least 1000g/bird/day) can
replace complete feeds in the finishing phase of slaughter ostriches and can play an important role in the
production of these birds. For lucerne intake, a quadratic relationship (P <0.01) was found between pasture dry
matter (DM) intake (g/bird/day) and supplementary feed intake (g/bird/day). The maximum lucerne intake level
(1692.8g/bird/day) was achieved at 619.6g supplementary feed/bird/day.
In the second grazing trial, finisher ostriches were allowed to graze lucerne pastures at two different stocking
rates (10 and 15 birds/ha) while receiving either 0 or 800g supplementary feed/bird/day. Ostriches receiving
supplementation had higher (P <0.05) mean end live weights than ostriches receiving no supplementation.
Ostriches receiving supplementation reached a mean target slaughter weight of 95kg within the timespan of the
trial, but ostriches receiving no supplementation did not. Stocking rate had no influence on mean end live weight
of the birds. An interaction (P <0.05) was found between the level of supplementation and stocking rate for ADG
of the birds. Stocking rate influenced ADG only for birds receiving no supplementation. As stocking rate
increased, ADG of birds receiving no supplementation declined. Results of the pasture data indicated an
increasing level of replacement of grazed lucerne DM by supplementary feed as the trial progressed and this
was more pronounced at the higher stocking rate of 15 birds per hectare. A high stocking rate seems to have
had a gradual depressing effect on lucerne DM production, while the less severe levels of defoliation at a lower
stocking rate promoted lucerne DM production.
A digestibility trial was conducted with mature ostriches (12 months old) to investigate the effect of
supplementation on intake and digestibility of nutrients, as well as to investigate the substitution effect that
ostriches may display when they receive supplementary feed in addition to grazing. The same dietary
treatments as in the first grazing study were given to ostriches while they were kept in metabolism crates. These
diets were also fed to 20-week old roosters to obtain energy values for these diets for roosters. These energy
values would be used to predict ostrich energy values for the same diets by means of a regression equation. For the roosters, each diet treatment was mixed with 50% maize to prevent digestive disorders and ensure
maximum feed intake. Ostriches started to substitute supplementary feed for pasture when supplementation
was supplied at levels higher than 62% (i.e. 1000g supplementary feed/bird/day) of total feed intake. For each
increase of 100g in supplementary feed intake, pasture was replaced at a rate of 4.9%. Higher (P <0.05) total
feed intakes were reached by ostriches if they grazed lucerne pastures and received supplementation than if
they grazed pasture alone. Pasture grazing alone had lower (P <0.05) dry matter digestibility (DMD) and
apparent metabolizable energy (AME) values for both ostriches and roosters than if pastures were supplied with
a supplement. A significant stepwise regression could not be computed for the prediction of ostrich AME values
from rooster AME values.
The economics of different feeding systems (extensive versus intensive) were evaluated with an economic
analysis, which was based on the same materials and methods and results of the first grazing trial. A margin
above feed cost (MAFC) analysis was performed to evaluate the economic viability of the different feeding
systems. The present value (PV) of the MAFC for the pasture-based system with 1000g/bird/day
supplementation was only 8.3% lower than that of the feedlot system over a period of six years, while the PV of
the cost of the same pasture-based system was 78.4% lower than that of the feedlot system. Birds finished on
lucerne pasture with 1000g supplementation led to a saving of 57% in feeding costs if compared to a feedlot
system. A sensitivity analysis of the MAFC revealed that the pasture-based system was less sensitive to
changes in feeding costs than the feedlot system. Therefore, the unique circumstances of each ostrich producer
will play a role in the decision whether to raise ostriches in a feedlot or on pastures. / AFRIKAANSE OPSOMMING: Die produksie van slagvolstruise in ‘n ekstensiewe weidingsstelsel met verskillende vlakke van aanvullende
voeding is gedurende hierdie studie ge-evalueer.
Twee weidingsstudies is uitgevoer. In die eerste studie is een groep afrondingsvolstruise (ses maande oud) in
‘n voerkraal geplaas en ‘n volledige afrondingsdieet gevoer. Die ander vier groepe is op besproeide
lusernweiding geplaas (teen ‘n weidigtheid van 15 voëls/ha) en het onderskeidelik 1500, 1000, 500 en 0g
aanvullende voeding/voël/dag ontvang. Weidingproduksie en -inname is gemeet. Daar was geen verskil (P
>0.05) tussen die eindgewigte van die voerkraal volstruise en dié van die weidende voëls wat onderskeidelik
1500 en 1000g aanvullende voeding ontvang het nie. Die gemiddelde daaglikse toename (GDT) van die groep
weidende voëls wat 1000g aanvullende voeding ontvang het was laer (P <0.05) as die GDT van die groep
weidende voëls wat 1500g aanvullende voeding ontvang het, maar al drie hierdie groepe het ‘n gemiddelde
teiken slaggewig van 95kg bereik binne die 154 dae van die studie. Weiding, tesame met die korrekte
aanvullende voeding (van ten minste 1000g/voël/dag) kan volvoer rantsoene in die afrondingsfase van
slagvolstruise vervang en kan dus ‘n belangrike rol speel ten opsigte van die produksie van hierdie voëls. Vir
lusern inname is ‘n kwadratiese passing (P <0.01) tussen weiding droë materiaal (DM) inname (g/voël/dag) en
aanvullende voeding inname (g/voël/dag) gevind. Die maksimum lusern inname (1692.8g/voël/dag) is bereik
wanneer voëls 619.6g aanvullende voeding/voël/dag ingeneem het.
In die tweede weidingsstudie, is afrondingsvolstruise (6 maande oud) toegelaat om lusern te bewei teen twee
verskillende weidigthede (10 en 15 voëls/ha) en het ook 0 of 800g aanvullende voeding/voël/dag ontvang.
Volstruise wat aanvullende voeding ontvang het, het hoër (P <0.05) gemiddelde eindgewigte bereik as volstruise
wat geen aanvullende voeding ontvang het nie. Volstruise wat aanvullende voeding ontvang het, het ook die
teiken slaggewig van 95kg bereik binne die tydsduur van die studie, terwyl die volstruise wat geen aanvullende
voeding ontvang het nie, nie daarin kon slag nie. Weidigtheid het nie ‘n invloed (P >0.05) gehad op die
eindgewigte van die voëls nie, maar ‘n interaksie (P <0.05) is gevind tussen vlak van aanvullende voeding en
weidigtheid wat GDT van die voëls betref. Weidigtheid het GDT beïnvloed slegs vir volstruise wat geen
aanvullende voeding ontvang het nie. Soos die weidigtheid van die voëls wat geen aanvullende voeding
ontvang het nie, toegeneem het, het die GDT van hierdie voëls afgeneem. Ontleding van die weidingsdata het
‘n toenemende vlak van verplasing van die weiding met aanvullende voeding getoon soos die studie gevorder
het en dit was meer merkbaar by die hoër weidigtheid. Die hoër weidighteid het ook gelei tot ‘n geleidelike
afname in lusern DM produksie, terwyl die minder aggressiewe vlakke van ontblaring by die laer weidigtheid
lusern DM produksie bevorder het.
‘n Verteringsstudie is gedoen met volwasse volstruise (12 maande oud) om die invloed van aanvullende voeding
op inname en verteerbaarheid van nutriente te toets, asook om die substitusie effek wat volstruise mag toon wanneer hulle aanvullende voeding ontvang op weiding, te ondersoek. Dieselfde dieet behandelings as in die
eerste weidingsstudie is vir die volstruise gegee terwyl hulle in metabolisme kratte aangehou is. Hierdie diëte is
ook aan 20-week oue hane gevoer om die energie waardes van die diete vir hane te verkry. Hierdie
energiewaardes sal dan gebruik word om volstruis energiewaardes te voorspel vir dieselfde diëte met behulp
van ‘n regressie vergelyking. Vir die hane is elke dieet gemeng met 50% mielies om inname te handhaaf en
spysverteringsstoornisse te voorkom. Volstruise het weiding begin verplaas met aanvullende voeding sodra die
vlak van aanvullende voeding hoër as 62% (d.i. meer as 1000g aanvullende voeding/voël/dag) van die totale
inname van die voëls was. Vir elke 100g toename in aanvullende voeding, word weiding verplaas teen ‘n tempo
van 4.9%. Weiding, tesame met aanvullende voeding, het gelei tot hoër totale droë material (DM) voerinnames
by volstruise as wanneer weiding alleen beskikbaar was. Wanneer weiding alleen voorsien was, was daar laer
(P <0.05) verteerbaarhede van DM en waarskynlike metaboliseerbare energie (WME) waardes vir beide
volstruise en hane as wanneer die weiding voorsien word met aanvullende voeding. Geen betekenisvolle
stapsgewyse regressie kon gevind word om volstruis energie waardes uit hoender energie waardes te voorspel
nie.
Die ekonomie van verskillende sisteme (ekstensief versus intensief) is in hierdie studie vergelyk en is gebaseer
op dieselfde materiaal en metodes en resultate van die eerste weidingsstudie. ‘n Marge bo voerkoste analise is
gebruik om die ekonomiese lewensvatbaarheid van die sisteme met mekaar te vergelyk. Die huidige waarde
van die marge bo voerkoste van die weidingssisteem waar 1000g aanvullende voeding gevoer word was 8.3%
laer as dié van die voerkraal sisteem oor ‘n periode van ses jaar. Daarteenoor was die huidige waarde van die
koste van dieselfde weidingssisteem 78.4% laer as dié van die voerkraal sisteem. Die weidingssisteem waar
volstruise 1000g aanvullende voeding ontvang het, het ‘n besparing van 57% in voerkoste getoon wanneer dit
met die voerkraal volstruise vergelyk is. ‘n Sensitiwiteitsanalise van die marge bo voerkoste het getoon dat die
weidingssisteem minder sensitief is vir wisselende voerkoste as die voerkraal sisteem. Die unieke
omstandighede van elke produsent sal ‘n rol speel in sy keuse om volstruise op weiding of in ‘n voerkraal af te
rond.
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Die verbetering van die benutting van laegraadse ruvoer vir wol- en vleisproduksie deur aanvulling van beskermde proteienbronne en/of aminosureBurger, Willem Jacobus 04 1900 (has links)
Thesis (MScAgric) -- University of Stellenbosch, 2002. / ENGLISH ABSTRACT: Low quality roughage is often used in the Western Cape as the only source of roughage
for the young growing ruminant. Production levels of these animals is unsatisfactory and
therefore supplementation is required. It is necessary when small grains are fed to also
include protein sources in the diets. For high production, these protein sources must also
be protected against rumen degradation. Good results are reported with the treatment of
sunflower oilcakemeal (SFOCM) with formaldehyde (0.86 g formaldehyde per 100 g
protein). Protecting methionine with 2-methyl maleic anhydride results in an increase in
wool production. This study looked at the effect on dry matter intake (DM-intake), wool
production and live weight change with supplementing a low quality diet with urea,
SFOCM and formaldehyde protected SFOCM (FSFOCM). These diets where also
supplemented with no methionine, methionine and 2-methyl maleyl methionine (MMM).
The DM-intake of total diet are increased (P<0.05) with the supplementing of oats straw
and barley (1.1% of live weight) diet with SFOCM and FSFOCM (949 & 935 vs 848
gis/d). Supplementing MMM decreased (P<0.05) the DM-intake with 9 %.
Supplementing FSFOCM increased (P<0.05) live weight change from 19 to 44 gis/d. Wool production are increased (P<0.05) with 38 % with supplementation of MMM. The
apparent digestibility of crude protein (CP) of the urea diet are increased (P<0.05) by
supplementing methionine when compared with no methionine supplementation (67.28
vs. 71.23 %). The apparent digestibility of crude protein (CP) of the SFOCM diet (63.71
and 64.96 vs. 70.15 %) and FSFOCM diet (66.39 and 66.26 vs. 70.89 %) are increased
(P<0.05) by supplementing MMM when compared with no methionine and methionine
supplementation. The apparent digestibility of fat of the SFOCM diet (61.01 and 65.65
vs. 48.33 %) and FSFOCM diet (60.93 and 63.83 vs. 38.14 %) are decreased (P<0.05) by
supplementing MMM when compared with no methionine and methionine
supplementation. The apparent nitrogen balance of the SFOCM diet (-0.15 and 5.41 vs.
4.62 gis/d) and FSFOCM diet (2.93 and 5.60 vs. 6.02 gis/d) are increased (P<0.05) by
supplementing MMM when compared with no methionine and methionine
supplementation. The DM- and CP-degradability of barley and DM-degradability of oats
straw did not differ (P<0.05) between different protein treatments. The higher production
with the supplementation of amino acids and proteins can be associated with more amino
acids available in the lower digestibility tract and not as a result of better rumen function. / AFRIKAANSE OPSOMMING: Die benutting van strooi as 'n laegraadse ruvoer deur die jong groeiende herkouer is 'n
algemene praktyk wat in die Weskaap toegepas word. Produksie is egter laag en
aanvulling van beperkende voedingstowwe is dus noodsaaklik. Saam met kleingrane
word proteïenbronne meestal as aanvulling gebruik. Vir hoë produksie is dit dikwels
nodig om proteïen aan te vul wat teen ruminale afbraak beskerm word. Die
formaldehiedbehandeling (0.86 g formaldehied per 100 g proteïen) van
sonneblomoliekoekmeel (SBOKM) is alreeds baie suksesvol toegepas vir die beskerming
van proteïen teen ruminale afbraak. Deur metionien met dimetielmaleïelsuuranhidried te
beskerm, is wolproduksie verhoog. Die studie het die effek van aanvulling van ureum,
SBOKM en formaldehiedbehandelde SBOKM (FSBOKM) saam met geen metionien,
metionien en 2,3 - dimetielmaleïelmetionien (MMM) op droëmateriaal (DM) -inname,
wolproduksie en liggaamsmassaverandering ondersoek. Die DM-inname van jong
Merinohamels op 'n hawerstrooi en gars (1.1% van liggaamsmassa) dieet is verhoog
(P<0.05) deur die aanvulling van SBOKM en FSBOKM (949 & 935 vs 848 g/s/d). Die
DM-inname is egter met 9 % verlaag (P<0.05) deur aanvulling van MMM. Die aanvulling van FSBOKM het die liggaamsmassatoename verhoog (P<0.05) van 19 na 44
gIs/d. Wolproduksie is met 38% (P<0.05) deur MMM-aanvulling verhoog. Die skynbare
verteerbaarheid van ruproteïen (RP) by die ureumbehandeling is verhoog (P<0.05) met
metionienaanvulling teenoor geen metionienaanvulling (67.28 vs. 71.23%). By SBOKM
(63.71 en 64.96 vs. 70.15%) en FSBOKM-behandelings (66.39 en 66.26 vs. 70.89%) is
skynbare verteerbaarheid van RP verhoog (P<0.05) met MMM-aanvulling teenoor
metionien- of geen-metionienaanvulling. By SBOKM (61.01 en 65.65 vs. 48.33%) en
FSBOKM-behandelings (60.93 en 63.83 vs. 38.14%) is skynbare verteerbaarheid van vet
verlaag (P<0.05) met MMM-aanvulling teenoor metionien- of geen metionienaanvulling.
By SBOKM (-0.15 en 5.41 vs. 4.62 gIs/d) en FSBOKM-bahandelings (2.93 en 5.60 vs.
6.02 gIs/d) is skynbare N-balans verlaag (P<0.05) met MMM-aanvulling teenoor
metionien- of geen-metionienaanvulling. Die effektiewe verteerbaarheid van DM en RP
van gars en effektiewe verteerbaarheid van DM van strooi is nie beïnvloed (P>0.05) deur
die aanvulling van proteïen nie. Die verhoogde produksie kan dus geassosieer word met
'n verhoogde voorsienning van aminosure in die SVK deur aanvulling en nie weens
verbetering in die rumenfunksie nie.
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The digestibility and degradability of feeds and protein sources in Dohne merino sheep and boer goatsVisagie, Willem 12 1900 (has links)
Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: The objective of this study was to evaluate Dohne Merino sheep and Boer goats in terms of the
degradable parameters of a high-fibre diet, a low-fibre diet and two vegetable protein sources
commonly used in South Africa. Differences between species were evaluated following the potential
differences within species. The feedstuffs used were those for the following diets: low-fibre diet (LF);
high-fibre diet (HF); sunflower meal (SFM) oilcake; and soybean meal (SBM) oilcake.
In the first trial, the digestible characteristics of the HF and LF diets were determined by means of a
digestibility study. A 6 × 6 Latin square design was used to determine whether Dohne Merino sheep
or Boer goat wethers differ regarding the digestibility characteristics of low- and high-fibre diets. The
diets were fed once daily at 1.24 kg to all the wethers, which had ad libitum access to fresh water.
Each period consisted of 10 days of adaptation and seven days of faecal and urinary sampling. The
results indicated that the intake and digestibility characteristics of nutrients did not differ between
sheep and goats. However, the different diets differed in terms of the nutrient intake and digestibility
range of sheep and goats.
The second trial was an in sacco degradability trial to determine the dry matter (DM) and crude protein
(CP) degradability of the LF, HF, SBM and SFM diets. Six Dohne Merino and six Boer goat wethers
were fitted with rumen cannulae so that they could be used in the trial. All wethers received the same
basal diet. The samples were incubated in the rumen in polyester Dacron bags, with the bags being
removed at intervals of 0h, 3h, 9h, 12h, 24h, 48h, 72h, and 96h for the LF and HF diets. All the
oilcake was removed at intervals of 0h, 2h, 4h, 8h, 12h, 16h, 24h, 36h and 48h. The sheep and goats
were found not to differ from one another in terms of effective degradability of any of the feedstuffs
concerned. However, within species differences were observed.
To establish a fully integrated outcome of degradability, the study described in the current thesis was
structured in such a way that the in vitro trial ran parallel with the in sacco trial, being performed with
the aid of a Daisy Incubator (ANKOM Technology Corp., Fairport, NY). Such a procedure was only
adopted in relation to the SFM and SBM diets in order to evaluate their in vitro data in relation to the in
sacco data. The same oilcake was tested in the case of both trials, with the composite sample of
rumen liquid of four sheep or goats, which was used in the in sacco trial, also being used in the in vitro
study. In the study, DM disappearance values were determined and fitted to a single-compartment
model by means of an iterative least-square procedure in order to determine the DM and CP
degradability parameters. The DM used in vitro or in sacco was compared, using the actual values
obtained after 8h incubation, due to only a limited amount of residue being left after incubation. In the study, the in vitro method overestimated the digestibility of SBM by 37% to 39% and the digestibility of
SFM by 17% to 20% compared with that found to occur in the in sacco method. In vitro DM
disappearance values for all SBM samples were found to be higher than those that were detected in
the SFM samples. The percentage of in vitro true digestibility parameters was also calculated. No
significant differences were found between species for effective degradability, though differences were
observed within species between the two substrates concerned.
In conclusion, the sheep and goats used in the study were not found to differ in terms of digestion
parameters when they were compared on different types of roughage or protein sources. However,
within species differences were, indeed, found to occur. Sheep and goats digested the SBM better
than they did the SFM. / AFRIKAANSE OPSOMMING: Die doel van hierdie studie was om te bepaal of Dohne Merino skape verskil van Boerbokke in terme
van degradeerbaarheidsparameters van ‘n hoë vesel-, ‘n lae veseldieët en twee plantaardige
proteïenbronne wat algemeen in Suid-Afrika gebruik word. Die verskille tussen spesies is ge-evalueer
en daarna die potensiële verskille binne spesies. Die volgende grondstowwe is geëvalueer: ‘n
laevesel-dieët (LF), ‘n hoëvesel-dieët (HF), sonneblom-oliekoekmeel (SFM) en sojaboon-oliekoekmeel
(SBM).
In die eerste proef is die degradeerbaarheidsparameters van die HF dieët en die LF dieët met behulp
van ‘n verteerbaarheidstudie bepaal. Dohne Merino hamels of Boerbok kapaters was gebruik om te
bepaal of skape en bokke verskil in terme van inname en degradeerbaarheid van voedingstowwe
wanneer hul hoë- en lae vesel voere gevoer word. Al die hamels en kapaters het ad libitum toegang
tot vars water gehad en hul was een keer per dag (1.24 kg) gevoer. Elke periode het bestaan uit ‘n 10
dag aanpassingsperiode en ‘n toegelate 7 dae vir mis- en urienmonster versameling. Die resultate het
aangedui dat die inname- en degradeerbaarheidsparameters van nutriënte beinvloed word deur
verskillende diëte binne spesies. Geen verskille is gevind tussen spesies wanneer daar hoë- en lae
kwaliteit voere gevoer is nie.
Die tweede proef was ‘n in sacco-degradeerbaarheidsstudie om te bepaal wat die droë materiaal
(DM) en ruproteïen (RP) verteerbaarheidsparameters van die HF dieët, die LF dieët, die SBM en die
SFM is. Ses Dohne Merino’s en ses Boer bokke met rumen kanullas is in die studie gebruik en al die
diere het dieselfde basale dieët ontvang. Die monsters is in die rumen geïnkubeer in poliester
dakronsakkies en die sakkies is verwyder na onderskeidelik 0 uur, 3 uur, 9 uur, 12 uur, 24 uur, 48 uur,
72 uur en 96 uur intervalle. Laasgenoemde intervalle was geldig vir die lae vesel- en hoëveseldieët.
Die oliekoeke se intervalle het verskil en is verwyder na 0 uur, 2 uur, 4 uur, 8 uur, 12 uur, 16 uur, 24
uur, 36 uur en 48 uur. Daar was geen verskille tussen spesies in effektiewe degradeerbaarheid nie,
alhoewel verskille voorgekom het binne spesies. Skape verteer veselagtige grondstowwe meer
effektief terwyl bokke weer hoë proteïn bevattende grondstowwe beter verteer.
Om ‘n volkome geïntegreede uitkoms van degradeerbaarheid te bewerkstellig is die in vitro proef en
die in sacco proef gelyktydig gedoen. Die in vitro-degradeerbareheidstudie is met behulp van ‘n
ANKOM Daisy Inkubeerder uitgevoer (ANKOM Tegnologie Korp., Fairport, NY) vir net die oliekoek
behandelings. Gedurende die studie is dieselfde oliekoeke gebruik. ‘n Saamgestelde monster van
die rumenvloeistof van vier van die skape of bokke wat vir die in sacco-studie gebruik was, is gebruik
vir die in vitro-inkubasie van die monsters. DM verdwyningparameters is bereken en dan met ‘n
interaktiewe kleinste kwadraat prosedure op ‘n een-kompartement model gepas om die in sacco DMdegradeerbaarheidsparameters
te bepaal. Die DM verdwyning, na 8h inkubasie, was gebruik om die in vitro en die in sacco metodes met mekaar te vergelyk, weens ‘n beperkte residu na die afloop van
die elke inkubasiestudie. Tydens die studie het die in vitro metode degradering oorskat in vergelyking
met die in sacco metode. DM verdwyningswaardes vir al die SBM monsters was hoër in vitro as die
SFM monsters. In die studie is die persentasie in vitro ware degradeerbaarheidswaardes bereken.
Geen verskille is opgemerk tussen spesies vir effektiewe degradeerbaarheid nie. Daar was wel
verskille binne spesies.
Om af te sluit het dit voorgekom dat skape en bokke nie verskil aan degradeerbaarheidswaardes
wanneer daar ‘n vergelyking was tussen verskillende vesels- en proteϊenbronne nie, alhoewel verskille
voorgekom het binne spesies. Skape en bokke het SBM effektief beter verteer as SFM.
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The use of fibrolytic enzymes in maize-soya based broiler dietsBotha, Corne J. 03 1900 (has links)
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.
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Substitution of maize with high fibre by-products in concentrates supplemented to dairy cows grazing kikuyu/ryegrass pasture during springLingnau, Werner August Leonhard 03 1900 (has links)
Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: Kikuyu over-sown with ryegrass forms the basis of pasture based systems in the Southern Cape. During
early spring, energy is the first limiting nutrient in kikuyu/ryegrass pasture, supplementation is thus
essential. Supplementation consists mainly of high starch concentrates (high maize inclusion), which is
expensive and could negatively affect rumen parameters. The objective of this study was to determine if
milk production could be improved or maintained, and if the rumen environment would be improved, by
replacing high starch concentrates with low starch (high by-product) concentrates for dairy cows on
kikuyu/ryegrass pasture.
Forty-five multiparous, high producing, lactating Jersey cows [body weight, 340 ± 34.7 kg; milk yield (MY),
19.6 ± 2.23kg/d; days in milk (DIM), 153 ± 33.5; lactation number, 3.6 ± 1.85; (mean ± SD)] were used in
the production study. A randomised block design was used. The forty-five cows were allocated to fifteen
groups of three each (blocking) on the basis of MY, DIM, and lactation number. Cows from each group
were randomly allocated to one of three treatment groups (high starch, medium starch and low starch
concentrate supplementation). Cows were fed 6kg (3kg during each milking) concentrate per day and
were allocated fresh pasture ad lib after each milking. There were no significant differences (P > 0.05)
found in milk yield and fat corrected milk yield between treatment groups. Milk fat percentage was
significantly higher (P < 0.05) in the low starch treatment than in the high starch treatment. Milk fat yield
was significantly higher (P < 0.05) in both the low starch and the medium starch treatment when
compared to the high starch treatment. Milk protein and lactose percentages, as well as milk urea
nitrogen and somatic cell count, did not differ significantly (P > 0.05) between treatments. Live weight
change, as well as body condition score change, was unaffected (P > 0.05) by treatments indicating body
reserves were not used to maintain milk production in the low starch treatment. A rumen metabolism study was also done with ten lactating, cannulated Jersey cows [body weight, 332 ±
56.3 kg; MY, 17.3 ± 1.73kg/d (mean ± SD)] were used. The cows were divided into two groups of five
each, on the basis of lactation number, DIM, and MY. The five cows from each group were randomly
allocated to one of two treatment groups (high starch and low starch concentrate supplementation) and
used in a cross-over design. Cows were fed 6kg concentrate per day and were allocated fresh pasture ad
lib after each milking. The volatile fatty acid (VFA) concentration was significantly higher (P < 0.05) in the
high starch treatment when compared to the low starch treatment. The individual VFA’s, acetic-,
propionic- and butyric acid concentrations were also significantly higher (P < 0.05) in the high starch
treatments when compared to the low starch treatment. The acetic to propionic acid ratio was unaffected
(P > 0.05) by treatment. Rumen ammonia-nitrogen concentration was significantly higher (P < 0.05) in the
high starch treatment. Rumen pH was unaffected (P > 0.05) by supplementation type. The in sacco dry
matter and neutral detergent fibre digestibilities of the kikuyu/ryegrass pasture were unaffected (P > 0.05)
by treatment type.
Results indicated that milk production could be maintained with low starch concentrates which also
improved milk composition. Results further suggested that the rumen environment was relatively
unaffected by low starch concentrate supplementation. / AFRIKAANSE OPSOMMING: Kikoejoe, oorgesaai met raaigras, vorm die basis van weidingstelsels in the Suid-Kaap. Tydens die
lentemaande is energie die eerste beperkende voedingstof op kikoejoe/raaigras weidings, wat
kragvoeraanvulling noodsaaklik maak. Aanvulling bestaan grootliks uit hoëstysel-kragvoer (hoë mielieinhoud)
wat nie net duur is nie, maar dit kan ook die rumenomgewing benadeel. Die doel van die studie
was om vas te stel of melkproduksievlakke onderhou kan word en of rumenomgewing verbeter kan word
deur die vervanging van hoëstysel-kragvoer met laestysel-kragvoer (hoë neweprodukinhoud) vir
melkkoeie op kikoejoe/raaigras weidingstelsels.
Vyf-en-veertig meervoudige pariteit-, hoë produserende, lakterende Jerseykoeie [liggaamsmassa, 340 ±
34.7 kg; melkproduksie, 19.6 ± 2.23kg/d; dae in melk, 153 ± 33.5; laktasienommer, 3.6 ± 1.85; (gem ±
standaardafwyking)] is gebruik vir die produksiestudie van die proef. Daar is gebruik gemaak van ‘n
ewekansige blokontwerp. Die vyf-en-veertig koeie is opgedeel in vyftien groepe van drie elk, gebaseer op
melkproduksie, dae in melk en laktasienommer. Koeie in elke groep is ewekansig aan een van drie
behandelings (hoëstysel-, mediumstysel- of laestysel-kragvoeraanvulling) geallokeer. Koeie is daagliks
6kg (3kg tydens twee milkings) kragvoer gevoer en vars weiding was ad lib beskikbaar na elke melking.
Daar was geen beduidende verskil (P > 0.05) in melkopbrengs of vet-gekorrigeerde melkopbrengs tussen
die drie behandelings nie. Bottervetpersentasie was beduidend hoër (P < 0.05) in die
laestyselbehandeling in vergelyking met die hoëstyselbehandeling. Bottervetopbrengs was beduidend
hoër (P < 0.05) in beide die laestysel- en mediumstyselbehandelings in vergelyking met die
hoëstyselbehandeling. Melkproteïen- en melklaktosepersentasies, asook melkureumstikstof en somatise
seltelling, was onveranderd (P > 0.05) tussen behandelinge. Liggaamsmassa en liggaamskondisietelling
het geen verskille (P > 0.05) getoon tussen behandelings nie, wat daarop dui dat liggaamsreserwes nie
gebruik is om melkproduksie in die laestyselbehandeling te onderhou nie. ‘n Rumenmetabolismestudie is ook uitgevoer met tien lakterende, gekannuleerde Jerseykoeie
[liggaamsmassa, 332 ± 56.3 kg; melkproduksie, 17.3 ± 1.73kg/d (gem ± standard afwyking)]. Die koeie is
in twee groepe van vyf elk verdeel, gebasseer op laktasienommer, dae in melk en melkproduksie. Die vyf
koeie van elke groep is in ‘n omslagontwerp gebruik en is ewekansig aan een van twee behandelings
(hoëstysel- of laestysel-kragvoeraanvulling) geallokeer. Koeie het daagliks 6kg kragvoer ontvang en vars
weiding was ad lib beskikbaar na elke melking. Die vlugtige vetsuurkonsentrasie was beduidend hoër (P
< 0.05) in die hoëstyselbehandeling as in die laestyselbehandeling. Die individuele vlugtige vetsure
naamlik asynsuur, propionsuur en bottersuur, was ook beduidend hoër (P < 0.05) in die
hoëstyselbehandeling as in die laestyselbehandeling. Die asynsuur- tot propionsuurverhoudings het geen
verskille (P > 0.05) tussen behandelings getoon nie. Rumen-ammoniakstikstof was beduidend hoër (P <
0.05) in die hoëstyselbehandeling as in die laestyselbehandeling. Rumen-pH het geen verskille (P > 0.05)
getoon tussen behandelings nie. Die in sacco droëmateriaal- en neutraalbestande veselverteerbaarhede
van kikoejoe/raaigras weiding het geen verskille (P > 0.05) tussen behandelings getoon nie.
Die resultate het aangedui dat melkproduksie onderhou kan word en dat melksamestelling verbeter kan
word met laestysel-kragvoeraanvulling. Resultate het ook daarop gedui dat die rumenomgewing nie
noodwendig verbeter word deur die aanvulling van laestysel-kragvoer vir koeie op kikoejoe/raaigras
weidings nie.
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The effect of fine particle removal from ground forage samples on In Saccro dry matter and neutral detergent fiber disappearance valuesMack, Claudia Isabell 03 1900 (has links)
Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: In vitro and in situ methods using the in sacco technique have a wide application in ruminant
nutrition as they allow the degradability and quality of forages and ruminant diets to be
determined quicker and at a lower cost than in vivo methods. These trials make use of artificial
fibre bags, made of polyester (dacron) or nylon which are available in variable pore sizes.
Results from such degradability trials are of great value to feed formulation programs such as
AMTS.cattle and CPM Dairy and the more accurate the results are obtained from such trials the
more accurate feed formulation models are enabling the ruminant nutritionist to formulate the
best diet possible to reach the genetic potential of ruminants. The accepted method for in sacco
trials (NRC, 2001) requires that the feed samples are ground through a 2 mm screen. This
usually results in a variety of particle sizes, including a significant amount of extremely fine
particles. Research has, however, shown that these fine particles can potentially be washed out
of the dacron bags that are used in in sacco degradability trials. This would result in an overestimation
of the soluble and rapidly fermentable nutrient fractions. The objective of this study
was to determine the effect of fine particle removal from ground forage samples on the chemical
composition and in vitro dry matter (DM) and neutral detergent fibre (NDF) degradability of
forages. Lucerne hay, oat hay and wheat straw samples were sourced from seven different
locations in the Western Cape. Samples were milled through a 2 mm screen and then sieved
through either 150 μm, 125 μm or 106 μm. All fractions were analysed for DM, crude protein
(CP), NDF, fat and ash. Based on the NDF content of the original samples, four samples from
each forage type were selected for in vitro trials to determine DM and NDF disappearance over
time. Samples were incubated for 0, 6, 24 and 48 hours in an ANKOM Daisy II incubator.
Significant variation occurred within forage types in terms of chemical composition. Fine particle removal had no effect on the NDF content of lucerne hay and wheat straw, but sieved oat hay
fractions had a higher NDF content than the un-sieved samples. The NDF content was on
average 635.9 for the sieved OH fractions, whereas the NDF content of the un-sieved samples
was 606.8. The CP content of sieved oat hay (61.4 on average) and wheat straw fractions (47.7
on average) were lower than the un-sieved fractions (65.7 for OH and 55.4 for WS), whereas for
lucerne hay, sieving had no effect on CP content.
Dry matter and NDF disappearances were significantly higher for the un-sieved samples than
for the sieved fractions for all three forage types at all incubation times, which indicates an overestimation
of the soluble and readily digestible forage fractions. Compared to sieved samples,
DMD values at 0 hours (washing only) of the un-sieved samples were, on average, 13.8%
higher for lucerne hay, 27.3% for oat hay and 44.7% for wheat straw. At 48 h, the overestimation
of lucerne DMD for the un-sieved samples was between 4.0% (compared to 106 μm
sieve) and 7.3% (compared to 150 μm sieve). This over-estimation in the un-sieved samples
was carried over to all four time points. No significant differences between the fractions (150,
125 and 106) were found within a forage type at all incubation times. The estimated degradation
rates and the predicted digested proportions were also significantly higher for the un-sieved
fractions compared to the sieved fractions. It was concluded that fine particle removal from
forage samples would result in more accurate estimations of in sacco nutrient degradability. / AFRIKAANSE OPSOMMING: In sacco in vitro- en in situ-metodes word dikwels toegepas in die studie van herkouervoeding
aangesien hierdie metodes vinniger, meer effektief en meer ekonomies is as in vivo-metodes.
Hierdie studies maak gebruik van kunsveselsakkies, gemaak van poliëster (dacron) of nylon wat
beskikbaar is in verskeie poriegroottes. Resultate van sulke verteringsproewe is belangrik vir
toepassing in voerformuleringsprogramme soos AMTS.cattle en CPM Dairy. Die resultate wat
deur hierdie studies verkry word, is belangrik vir akkurate voerformulering deur formuleringsmodelle
en stel die herkouervoedingkundige in staat om die ideale voer te formuleer vir die
manifestering van die dier se genetiese potensieaal. Die aanvaarde in sacco-metode (NRC,
2001) vereis dat voermonsters deur ‘n 2 mm sif gemaal word wat ‘n groot verskeidenheid
partikelgroottes tot gevolg het met ‘n beduidende hoeveelheid baie fyn materiaal. Navorsing het
getoon dat hierdie baie fyn partikels uit die dacronsakkies gewas kan word tydens in sacco
verteringstudies, met die gevolg dat die oplosbare en vinnig-verteerbare fraksie oorskat kan
word. Die doel van die huidige studie was om die invloed van die verwydering van fyn partikels
op die chemiese samestelling van ruvoermonsters te bepaal, asook die in vitro droë materiaal
(DM) en neutraal-onoplosbaare vesel (NDF) verteerbaarheid daarvan. Monsters van lusernhooi,
hawerhooi en koringstrooi, afkomstig van sewe verskillende lokaliteite in die Wes-Kaap, is deur
'n 2 mm sif gemaal en sub-monsters is deur ‘n reeks siwwe met poriegroottes van 150 μm, 125
μm of 106 μm gesif. Al die fraksies is geanaliseer vir DM, ruproteïen (RP), NDF, vet en as. Vier
monsters van elke voertipe is op grond van die NDF-inhoud geselekteer vir in vitro-studies om
die DM- en NDF- verteerbaarheid oor tyd te bepaal. Monsters is vir 0, 6, 24 of 48 uur
geïnkubeer. Die resultate het getoon dat daar betekenisvolle variasie in chemiese samestelling
binne ruvoertipes voorgekom het. Die verwydering van die fyn partikels het geen invloed die NDF-inhoud van lusernhooi en koringstrooi gehad nie. Wat hawerhooi betref, was die NDFinhoud
van die gesifte monsters egter betekenisvol hoër in vergelyking met die ongesifte
monsters. Die NDF inhoud was gemiddeld 635.9 vir die gesifte monsters en vir die ongesifte
monsters 606.8. Sifting het geen invloed op die RP-inhoud van lusernhooi gehad nie, maar vir
hawerhooi (61.4 gemiddeld) en koringstrooi (47.7 gemiddeld) was die RP-inhoud van die gesifte
monsters betekenisvol laer as dié van die ongesifte monsters (65.7 vir hawerhooi en 55.4 vir
koringstrooi).
In vergelyking met die gesifte monsters, was die in vitro DM- en NDF-verteerbaarhede
betekenisvol hoër vir die ongesifte monsters vir al drie ruvoertipes by alle inkubasietye. Hierdie
resultate bevestig ‘n oorskatting van oplosbare en maklik verteerbare fraksies in gemaalde
voermonsters. In vergelyking met die gesifte monsters, was die DMV-waardes van die ongesifte
monsters by 0 ure (slegs gewas) gemiddeld 13.8% hoër vir lusernhooi, 27.3% vir hawerhooi en
44.7% vir koringstrooi. Na 48 h inkubasie was die oorskatting van lusern DMV vir die ongesifte
monsters tussen 4.0% (vergeleke met die 106 μm sif) en 7.3% (vergeleke met 150 μm sif). Die
oorskatting is oorgedra na al vier inkubasietye. Die resultate het geen noemenswaardige
verskille tussen die fraksies (150 μm, 125 μm en 106 μm poriegroottes) van ‘n ruvoertipe by
enige inkubasietyd aangedui nie. Die beraamde verteringstempo’s en verteerde fraksies was
ook aansienlik hoër vir die ongesifte monsters in vergelyking met die gesifte monsters. Die
gevolgtrekking is gemaak dat die verwydering van fyn partikels uit gemaalde ruvoermonsters
die akkurate bepaling van in sacco verteerbaarheidswaardes verhoog.
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Volstruis as slagdier : aspekte van groeiMellett, Francois D. 12 1900 (has links)
Thesis (PhD(Agric) (Animal Sciences))--Univsersity of Stellenbosch, 1992. / The anatomy of the muscles of the hindquarters of the ostrich is described and presented graphically for the purpose of the present and future studies in meat science involving the ostrich. In the past, the lack of an accurate anatomical description of this species has led to the incorrect identification of certain muscles by researchers.
The process of growth is described for 51 components of the ostrich body, which includes 21 muscles and four organs. Gompertz functions were calculated to formulate growth models for these components. Acceptable goodness-of-fit was obtained for the formulated models regarding the raw skin area, mass of the head, heart, filet and other muscles as well as certain bones. No information on similar models could he found for the description of growth of individual muscles or body parts of other meat animals. However, similar growth models are available for the description of live mass changes over time. Since the general growth curve is
sigmoidal it is difficult to fit accurate curves by arithmetical methods. This has led to the development of simpler linear models, which express the growth of a body part relative to the growth of the same entire body. Time based predictions of yield are thus impossible. In fact, many of these allometric equations are simply in a different mathematical form, rather than being totally different equations. Furthermore, the latter equations cannot be used to predict accurate values at the positive and negative extremes since unrealistic values are obtained. Computer programs are presented in the dissertation which can be used without modification on various species, such as fish, poultry, plants and forests, as well as micro organisms in plant pathology, food science and sewage. With the development in computer technology and by means of the suggested programs, it is possible to describe the growth process on a time scale with ease. It is also possible to estimate the mass of any body part at birth (and possibly at conception) as well as at maturity. Evidence is provided that unrealistic asymptotic values are obtained with time based linear and polynomial functions as well as with published non linear allometric models for the description of growth in the ostrich. A goodness-of-fit test for the
Gompertz function is presented. It is advisable to carry out this test before fitting alternative models, since the relationship between two variables is only linear on a double log scale when both variables can be described by similar functions on a time scale. A method for the calculation of the standard error at the point where maximum growth occurs is also presented. These methods can successfully be used for any of the above mentioned species.
The point at which maximum growth occurred was used to compare the muscles of the hindquarters of the ostrich with that of Merino rams. This showed that these two species differ markedly in this regard. Furthermore, it was proved that certain economically important muscles still gained weight after the optimal skin size (120 dm2) was reached at the age of ten months. It is also shown that the fat content of ostrich meat (filet) varied independently of the abdominal fat content, and that it reached a minimum value of 0.3% at the popular slaughter age of 14 months. Reliable methods for age estimation of a slaughtered bird is presented, based on the growth models. This information can be used to develop a classification system for ostrich meat and other meat animals.
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The effect of the dietary inclusion of canola oilcake, full-fat canola and sweet lupins on the production performance and fat composition of broilers and pigsSmith, Natasha 03 1900 (has links)
Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2005. / The demand for protein for human and animal nutrition in South Africa is increasing and it will
continuously increase. The effect of replacing soybean oilcake meal as protein source for broilers and full-fat
soybean meal for weaner pigs, with different levels of sweet lupins (Lupinus angustifolius), canola oilcake
and full-fat canola was examined. A basal diet with soybean oilcake as protein source was mixed with a diet
using either sweet lupins or canola oilcake or full-fat canola in ratios of 100%, 67% and 33% respectively. In
the broiler trial the test diets were fed for a period of six weeks with or without the enzyme Vegpro (Alltech).
Pigs were fed the test diets, with and without Roxazyme® enzyme, ad libitum from 8.5 to 25 kg live weight.
The fatty acid content of the fat pads of the broilers raised on the different diets was determined. The pigs
were kept in the trial up to the grower- finisher phase. The fatty acid content of the carcass fat and muscle of
pigs raised on the different diets was determined. The inclusion of enzymes had no effect on the growth, feed
intake or feed conversion ratio of broilers fed the test diets. The provision of external dietary enzymes to the
weaner pig diets failed to improve either dry matter intake or growth rate, but improved the feed conversion
ratio. Broiler weights at six weeks of age were significantly higher for the control diet compared to the 20%
lupin diet. There was no significant difference in the feed intake as the lupin content of the diets increased.
The feed conversion ratio did not differ significantly between the control diet and the 6.6% lupin diet but
became significantly poorer as the lupin content increased to 13.2% and 20% of the test diet. There were no
significant differences in production performance of the control diet and the canola oilcake containing diet.
The broiler weights at six weeks decreased significantly with each increase in the canola oilcake content of
the diets. The feed intake of the 20% canola oilcake diet at week six was significantly less than the intake of
the control diet, but not significantly less than the 6.6% and 13.2% canola oilcake diets. The feed conversion
ratio of the control diet was significantly better than the 13.2% and 20% canola oilcake diets. No significant
differences were found in week six between the 6.6% full-fat canola diet and the control diet for broiler
weights and feed intake. The feed conversion ratio of the broilers fed the 13.2% and 20% full-fat canola diets
was significantly poorer than the control diet. The final body weights of the weaner piglets fed the control diet were significantly higher than the final body weights of weaner piglets fed the lupin containing diets.
The average daily gain of the weaner piglets fed the control diet was significantly higher than the gain of the
weaner piglets fed the lupin containing diets. No significant differences in the feed intake and feed
conversion ratio between the different lupin inclusion levels were detected. There were no significant
differences in body weight, feed intake, average daily gain and the feed conversion ratio, between the various
full-fat canola containing diets and the control diet. A significant difference in body weight was found
between the weaner piglets fed the 20% canola oilcake diet and the weaner piglets fed the control diet. There
were no significant differences in feed intake between the various inclusion levels of canola oilcake. The
control and 6.6% canola oilcake containing diets had significantly higher average daily gains than the 20%
canola oilcake containing diet. In the final trial the finisher pigs fed the test diet containing 25.00% lupins,
had a final body weight significantly lighter than the final body weight of the finisher pigs fed the other test
diets. The finisher pigs fed the test diet containing 25.00% lupins, also had a significantly reduced average
daily gain and feed intake. The feed intake of the 25.00% canola oilcake diet was significantly lees than the
feed intake of the 16.75% full-fat canola containing diet. The feed conversion ratio of the 25.00% lupin
containing diet was significantly poorer than the feed conversion ratio of the 16.75% lupin containing diet,
8.25% lupin containing diet, 16.75% full-fat canola containing diet, 25.00% canola oilcake containing diet
and the control diet.
In a choice feeding trial growing pigs were offered four diets with four different protein sources:
sweet lupins (25% inclusion level), canola oilcake (25% inclusion level), full-fat canola (25% inclusion
level) and soybean oilcake (25% inclusion level), while their daily intakes were recorded. In a second choice
feeding trial pigs were offered ten different diets with increasing levels (6.6%, 13.2%, 20%) of either sweet
lupins, canola oilcake meal or full-fat canola meal. The pigs consumed significantly more of the soybean
oilcake containing diet compared to diets containing the alternative protein sources. Pigs consumed
significantly less of the full-fat canola diet compared to the sweet lupin and canola oilcake diets.
Ten different canola cultivars were collected from two different locations in the Mediterranean
rainfall area of South Africa namely the Western Cape (Swartland) and Southern Cape (Rûens) grain
producing areas. The sinapine and glucosinolate content of various canola cultivars was compared and the
influence of locality on the sinapine and glucosinolate content of the canola cultivars was determined. There
were no significant differences (P < 0.05) in sinapine content when the canola produced in the Western and
Southern Cape were compared. Varola 54 and Rainbow cultivars had significantly higher (P < 0.05) sinapine
contents compared to the Varola 50 cultivar.
Samples of lupins, field peas, faba beans and narbon beans were collected and analysed for amino
acids, alkaloids, non-starch polysaccharides, tannin and starch. The digestible energy value of these
alternative protein sources for pigs was determined. Significant differences were found in the amino acid
content of the various crops. The alkaloid content of the lupins varied significantly between the sweet and
bitter lupin varieties. Sweet L. angustifolius cultivars contained ca 50mg/kg and the bitter L. angustifolius cultivars ca 15000mg/kg alkaloids. The mean alkaloid content of L. albus cultivars was ca 1300mg/kg. The
faba beans, narbon beans and peas had significantly higher values for tannins and starch, compared to lupins.
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