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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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Investigating the high incidence of bone disorders in a broiler farm : a case studyMkhize, Felicity Nomfuzo 03 1900 (has links)
Thesis (MPhil (Animal Sciences))--University of Stellenbosch, 2006. / Rickets is described as a disease that affects young growing poultry. Poorly mineralized bones with thickened and irregular growth plates characterize it. The onset of rickets is characterized by a failure of mineralization of cartilage and bone. Other symptoms of rickets include reluctance to movement in affected birds. These birds will sit on their hocks and if startled they use their wings for balance. On necropsy, bones are soft and fragile and they have thickened growth plates. In this study 30% of the chicks aged between 7 and 8 days from a broiler flock, started showing splay leg problems. Affected chicks were unable to support their weight on their legs, some showing paralysis. The bones were soft and rubbery. To try and identify the possible cause, bones from the affected chicks were analyzed for calcium (Ca) and phosphorus (P) to determine the Ca:P ratio. Blood serum was also analyzed for the mineral content. Ca and P were the main focus of the tests as the problem was suspected to be rickets. The feed was analyzed for protein, Ca and P. The bone analysis showed a Ca:P ratio of less than 2:1, while results of the blood serum showed an inverse Ca: P ratio. The analysis results of the feed as well as the bones showed an imbalance in the Ca:P ratio which according to literature and research done is a possible cause for rickets. These findings combined with the symptoms displayed by the affected birds, lead to the suggestion that the problem in this study was rickets.
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Extraction and biomedical application of peripheral blood stem cells in sheep and horsesStrydom, Aliki Veruschka 12 1900 (has links)
Thesis (PhD (Physiological Sciences))--University of Stellenbosch, 2007. / SUPERFICIAL digital flexor tendon injury has a serious negative impact on the
competitive horse industry. Injured horses require up to a year of rest for recovery and
likelihood of re-injury upon return to normal activity is as high as 80 %. Tendon healing
requires (a) production of collagen by fibroblasts, to provide tensile strength and elasticity to
the tendon, (b) minimisation of restrictive fibrosis, which compromises tendon gliding
function and (c) minimisation of peritendinous adhesions. We review conventional
treatments for tendon healing before exploring stem cell application as a therapeutic
alternative. We promote the use of hematopoietic and mesenchymal stem cells derived from
adult peripheral blood - as opposed to bone marrow-derived stem cells or embryonic stem cell
sources - and review published research output in this regard. In conclusion, we outline our
research objectives and present and discuss our results in the chapters that follow.
Mononuclear cells - consisting of hematopoietic stem cells, mesenchymal stem cells
and leucocytes – were isolated from the peripheral blood of sheep and horses through red
blood cell lysis and blood plasma extraction. Cell counts and propidium iodide dye exclusion
viability tests were conducted on the cell pellets. Sheep sub samples were tested for CD45
expression and horse sub samples for CD4 and CD11a/18 cell surface markers by flow
cytometry for characterisation purposes. In both cases, separate sub samples were incubated
with matched immunoglobulin (IgG) isotypes, conjugated to fluorescein isothiocyanate
(FITC), to serve as controls. For the culture of mononuclear cells, 4.5 x 106 cells were
selected for autologous sheep injections, 3 x 106 CD45- cells for allogeneic sheep injections
(the latter excluding leucocytes that may induce an immune response) and 72 x 106 cells for
horse injections. These cells were incubated with bromo-deoxyuridine (BrdU), cultured and
subsets were extracted for a second round of cell counts and viability tests before being
resuspended in blood plasma. For the horse samples an additional 1 x 106 mononuclear cells
were incubated until reaching 60 % confluence and tested for myogenic differentiation. Low
cell mortality and lack of fluorescence from IgG-FITC controls reflected effective protocols
and a lack of false positive results. The fact that the equine cell population differentiated into
myotubes verified the presence of mesenchymal stem cells in injections.
We tested whether surgical incisions or collagenase injections best mimicked naturally
occurring tendon injuries and compiled macroscopic and microscopic descriptions of tendon
injury sites at seven weeks post-injury. The superficial digital flexor tendons of 27 sheep
received an incision, a collagenase injection or a saline control injection. After one week a number of sheep were sacrificed while the remainder received further saline treatment and
were sacrificed after another seven weeks. Tendons were examined through clinical
observations, image analysis of maximum tendon diameter, mechanical testing and
histological sectioning of affected tissues. Collagenase-induced injury resembled tendonitis
more closely than surgically-induced injury. Collagenase-injured tendons (a) induced
lengthier lameness in affected limbs, (b) were more swollen and difficult to palpate, (c)
assumed the bow appearance characteristic of natural injury, (d) experienced extensive
haemorrhage due to collagen lysis, (e) had decreased elasticity and capacity to carry loads and
stress, (f) displayed decreased stiffness due to collagen fibre disruption and (g) developed
severe inflammation. After seven weeks injured tendons displayed increased vascularisation
in the areas of haemorrhage and in the adjacent collagen matrix. High inflammation rates and
low collagen levels however still persisted.
Collagenase injections were used to induce tendonitis in the superficial digital flexor
tendons of 27 sheep. After one week these tendons received treatment with a control saline
solution, autologous peripheral blood mononuclear cells (MNCs) or allogeneic peripheral
blood CD45- MNCs. Healing rates were compared after a further seven week period by
conducting ultrasonographic evaluations, clinical observations, image analyses of maximum
tendon diameter, mechanical tests and histological investigations. Tendons treated with
MNCs displayed an improvement in echogenicity and fibre linearity, higher and more
organised collagen levels, stronger mechanical properties and less swelling. Although these
improvements were not always significant, they provided strong evidence to suggest marked
healing benefits over a longer time period.
Collagenase injections were used to induce tendonitis in the superficial digital flexor
tendons of four horses. After one week these tendons received treatment with either a control
saline solution or autologous peripheral blood mononuclear cells (MNCs). Healing rates were
compared after a further seven week period by conducting ultrasonographic evaluations,
clinical observations, image analysis of maximum tendon diameter and histological
investigations. Tendons treated with MNCs displayed significant improvements in fibre
linearity in the direct vicinity of the lesion, as well as recovery rate thereof, and experienced
less swelling when compared with their untreated counterparts. Healing trends suggested
that, given a longer period of observation post-injury, more significant improvements may
become apparent.
Human adipose tissue is known be an easily accessible and high yielding source of
multipotent mesenchymal stem cells. These stem cells could potentially be used for therapeutic advancement of tendon regeneration. Our first goal was to examine the in vitro
myogenic differentiation potential of adipose-derived, adherent mononuclear cells (MNCs)
from six adult sheep. The second goal was to characterise the population of cells isolated
through various available ovine specific, non-mesenchymal stem cell surface markers,
namely, CD1, CD31, CD34 and CD45. After incubation, only four of the six MNC cultures
started to proliferate. These four cultures all exhibited high myogenic differentiation ability.
The isolated cell populations did not express any of the non-mesenchymal stem cell specific
cell surface markers.
In conclusion, our data suggests that peripheral blood stem cells and adipose-derived
stem cells are important candidate cell types for therapeutic application to improve tendon
repair in horses and sheep. Sufficient time must be allowed following injury and prior to stem
cell treatment (at least one month) and a controlled exercise program should be followed posttreatment.
A larger sample size is required and at least six months of recovery before
macroscopic and histological repair can be analysed more accurately and conclusively.
Ultrasonography should be carried out on a continuous basis, as it is a non-invasive method of
monitoring change over time.
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The effect of inoculants on silage fermentation properties and on animal productionMeeske, Robin 12 1900 (has links)
162 leaves printed on single pages, preliminary pages i- vii and numbered pages 1-152. Includes bibliography and abbreviations. / Digitized at 600 dpi grayscale to pdf format (OCR), using a Bizhub 250 Konica Minolta Scanner. / Thesis (PhD(Agric))--University of Stellenbosch, 2000. / ENGLISH ABSTRACT: Maize, forage sorghum, lucerne, oats, barley and triticale are the most common silage crops in
South Africa, while tropical grasses like Eragrostis curvula and Digitaria eriantha are ensiled
to a lesser extent. The aim of this study was to determine the effect of adding a lactic acid
bacterial inoculant to E. curvula, D. eriantha, lucerne, forage sorghum, maize and oat silage.
The effect of the addition of a lactic acid bacterial inoculant when ensiling E. curvula on the
fermentation dynamics during ensiling and the aerobic stability of the silage was determined. The
addition of the lactic acid bacterial inoculant to E. curvula at ensiling resulted in a more rapid
lowering in pH and improved preservation. Inoculated silage had a higher lactic acid content, less
protein breakdown and a lower butyric acid content compared to that of the control silage. Both
silages were stable when exposed to air for five days.
Digitaria eriantha was ensiled, with or without the addition of a lactic acid bacterial inoculant
containing Lactobacillus plantarum. Streptococcus faecium and Pediococcus acidilactici
together with the enzymes, cellulase, hemicellulase and amylase. The addition of the inoculant
resulted in a more rapid drop in pH, a higher level of lactic acid, an increase in the number of
lactic acid bacteria, less protein breakdown and lower numbers of enterobacteria, clostridial
spores, yeast and mould compared to the control silage. Digitaria eriantha hay, control and
inoculated silage diets were fed to 24 Merino rams (n = 8 per treatment) to determine intake and
digestibility. The intake of diets consisting of 90.9% D. eriantha hay, control silage or inoculated
silage, differed significantly (p<0.05) at 1395, 1540 and 1848 g DM/day, respectively. The in vivo organic matter digestibility (glkg) of D. eriantha hay, untreated silage and inoculated silage
diets was 561, 546, 574, respectively. The addition of the bacterial inoculant when ensiling D.eriantha resulted in better preservation, improved aerobic stability, as well as a higher in vivo
organic matter digestibility and intake of D. eriantha silage.
The addition of an inoculant or molasses to lucerne (Medicago sativa), ensiled in laboratory silos
was investigated. The addition of the additives resulted in an increased preservation rate as
indicated by a more rapid lowering of pH, a faster rate of lactic acid production and less protein
breakdown compared to control silage. The inoculant was more effective than the molasses in
improving the rate of preservation. The aerobic stability of lucerne silage was not affected by
inoculation or the addition of molasses. The addition of an inoculant to wilted big bale lucerne
silage was studied. The inoculant improved silage quality as indicated by a lower pH, higher
lactic acid content, lower ammonia nitrogen content and lower level of butyric acid in inoculated
silage compared to the control lucerne silage. The composition of big round bale lucerne silage
differed markedly from that of lucerne ensiled in laboratory silos as the former had a higher pH,
ammonia nitrogen, butyric acid and acetic acid content and a lower lactic content.
Whole crop forage sorghum cultivar FS2 was harvested at the late bloom (20.7% DM) and soft
dough (28.9% DM) stages of maturity and ensiled in laboratory silos with the addition
of commercial silage inoculants. At both stages of maturity the inoculants caused a more rapid rate
of pH decline and a higher amount of lactic acid production. All the silages were well preserved.
Silages of the sorghum ensiled at the late bloom stage with all treatments were stable after 5 days
of aerobic exposure, whereas sorghum ensiled at the soft dough stage with the addition of the
inoculants deteriorated upon aerobic exposure. It is concluded that addition of lactic acid
bacterial inoculants to mature sorghum at ensiling might impair the aerobic stability of the silage.
The yield, nutritional value and production potential of silage made from twenty one maize
hybrids was compared. It was concluded that maize hybrids did differ in metabolizable energy
content, rate of digestion, predicted intake and predicted milk production potential. The content
of NDF and ADF did not differ between the maize hybrids used in this study and could therefore
not be used to predict nutritional value or production potential.
Maize was harvested at the hard dough stage and ensiled with or without the addition of a lactic
acid bacterial inoculant in laboratory silos and in 210 litre drums. The adding of the inoculant
to maize at ensiling did not result in a more rapid drop in pH and higher levels of lactic acid. The
intake and growth of South African Mutton Merino lambs fed inoculated and untreated maize
silage diets was determined. The average daily gain of lambs fed a diet consisting of either 60%
control or inoculated maize silage over a growth period of 60 days was 239 ± 26 and 255 ± 44
g/day, respectively. Although the laboratory study showed very little effect of adding a lactic acid bacterial inoculant to maize at ensiling, lambs tended to consume more of the inoculated silage.
In the second study the effect of the addition of a lactic acid bacterial inoculant with an enzyme
to maize at ensiling on the fermentation dynamics during ensiling, aerobic stability of the silage,
the intake, milk production and milk composition of Jersey cows fed maize silage diets was
determined. The inoculant did not result in a more rapid lowering of the pH or a more rapid
lactic acid production compared to untreated maize silage made in laboratory silos. Both the
control and inoculated maize silages were well preserved. The addition of the inoculant to maize
at ensiling improved the palatability, intake and the aerobic stability of maize silage compared
to the untreated control maize silage. Milk production, milk composition, live weight and
condition score of Jersey cows was not significantly affected by the addition of the inoculant to
maize silage.
The effect of the addition of an enzyme containing lactic acid bacterial inoculant to big bale
oat (Avena sativa, cv Cederberg) silage on silage composition, silage intake, milk production and
milk composition of Jersey cows was determined. The crop was cut at the bloom stage, wilted
and ensiled in big round bales. The inoculant, Sil-All, was applied during the baling process on
half of the bales. Silages were fed to Jersey cows in an intake and milk production study. Both
the control and inoculated oat silages were well preserved. The inoculated oat silage had a lower
level of butyric acid than the control oat silage. Cows fed the inoculated oat silage produced
more (P=O.05) milk (17.7 kg/day) than cows fed the control oat silage (16.7 kg/day). The
addition of a lactic acid bacterial inoculant to big bale oat silage improved silage composition
and animal performance.
This study clearly showed that the composition of silages made in bunker silos under
commercial farm conditions differ largely from that of silages made in small scale laboratory
silos. When the effect of silage additives on aerobic stability of silage is determined the
evaluation should include studies on large scale bunker silages. Evaluation of silage additives
should include intake and animal production studies. / AFRIKAANSE OPSOMMING: Mielies, voersorghum, lusem, hawer, gars en korog word algemeen as kuilvoer gewasse benut
terwyl tropiese grasse soos Eragrostis curvula en Digitaria eriantha tot 'n mindere mate
ingekuil word. Die doel van hierdie studie was om die invloed van 'n melksuurbakterieseinokulant
op E. curvula-, D. eriantha-, lusem-, voersorghum-, mielie- en hawerkuilvoer te
bepaal.
Die invloed van 'n melksuurbakteriese-inokulant op die fermentasiedinamika en die aerobiese
stabiliteit van E. curvula-kuilvoer is bepaal. Die toediening van die melksuurbakterieseinokulant
tot E. curvula tydens inkuiling het 'n vinniger tempo van pH daling en beter
preservering tot gevolg gehad in vergelyking met kontrole kuilvoer. Inokulant behandelde
kuilvoer het 'n hoer melksuurinhoud, minder protei'en afbraak en 'n laer bottersuurinhoud as
kontrole kuilvoer gehad. Beide kuilvoere was stabiel tydens blootstelling aan lug vir vyf dae.
Digitaria eriantha is ingekuil met ofsonder die toediening van 'n melksuurbakteriese-inokulant
wat Lactobacillus plantarum. Streptococcus faecium en Pediococcus acidilactici sowel as die
ensieme, sellulase, hemisellulase and amilase bevat het. Die inokulant het 'n vinniger tempo van
pH-daling, hoer vlakke van melksuur en melksuurbakterie, minder protei'en afbraak en laer
getalle van enterobakterie, klostridiale spore, giste and swamme in vergelyking met die kontrole
tot gevolg gehad. Digitaria eriantha hooi, kontrole kuilvoer en gei'nokuleerde kuilvoer diete is
aan 24 Merino ramme (n = 8 per behandeling) gevoer vir bepaling van inname en
verteerbaarheid. Die inname van diete wat uit 90.9% D. eriantha hooi, kontrole kuilvoer of
gei'nokuleerde kuilvoer bestaan het, het betekenisvol (p<0.05) verskil en was 1395, 1540 en 1848
gDM/dag, respektiewelik. Die in vivo organiesemateriaal verteerbaarheid (gIkg) vanD. eriantha
hooi, kontrole kuilvoer en geYnokuleerde kuilvoer was 561, 546, 574, respektiewelik. Die
toediening van die bakteriese-inokulant tydens inkuiling vanD. eriantha het beter preservering,
verbeterde aerobiese stabiliteit asook 'n hoer in vivo organiesemateriaal verteerbaarheid van D.
eriantha kuilvoer tot gevolg gehad.
Die effek van toediening van 'n melksuurbakteriese-inokulant en van molasse tot lusem
(Medicago sativa) ingekuil in laboratoriumsilos is ondersoek. Die inokulant toediening en
molasse toediening het die tempo van preservering versnel, die pH het vinniger gedaal, melksuur
is teen 'n hoer tempo geproduseer en minder proteYen afbraak het plaasgevind in vergelyking met
die kontrole kuilvoer. Die tempo van preservering is meer effektief deur toediening van die
inokulant verhoog as deur die toediening van molasse. Die aerobiese stabiliteit van
lusernkuilvoer is nie beYnvloed deur die toediening van inokulant ofmolasse nie. Die effek van
die toediening van 'n melksuurbakteriese-inokulant tot groot rondebaal lusernkuilvoer is
ondersoek. Die inokulant het die kwaliteit van die kuilvoer verbeter en het 'n laer pH, hoer
melksuur, laer ammoniak stikstofen laer bottersuurinhoud in rondebaallusernkuilvoer tot gevolg
gehad in vergelyking met kontrole kuilvoer. Groot rondebaallusernkuilvoer het grootliks verskil
van lusernkuilvoer wat in laboratoriumsilos ingekuil is. Die rondebaal kuilvoer het 'n hoer pH,
hoer ammoniak-stikstof-, bottersuur- en asynsuurinhoud en 'n laer melksuurinhoud gehad as
laboratorium lusernkuilvoer.
Voersorghum kultivar FS2 is op die laat blom (20.7% DM) en op die sagte deeg (28.9% DM)
stadium met die byvoeging van melksuurbakteriese-inokulante ingekuil in laboratoriumsilos.
Toediening van beide inokulante tot sorghum hetop beide die inkuilstadiums gelei tot 'n vinniger
tempo van pHdaling en meer melksuurproduksie. Aile kuilvoere insluitend die kontrole kuilvoer
was goed gepreserveer. Kontrole sowel geYnokuleerde sorghumkuilvoer ingekuil op die laat
blomstadium was stabiel tydens aerobiese blootstelling vir 5 dae. Sorghumkuilvoer ingekuil op
die sagtedeegstadium met die byvoeging van inokulante was onstabiel tydens aerobiese
blootstelling. Die toediening van melksuurbakteriese-inokulante tot sorghum wat op die
sagtedeegstadium ingekuil word kan aerobiese stabiliteit van die kuilvoer grootliks benadeel.
Die opbrengs, voedingswaarde en produksiepotensiaal van kuilvoer gemaak van 21 mielie
hibriede is vergelyk. Verskille in metaboliseerbare energie inhoud, tempo van vertering,
voorspelde inname en voorspelde melkproduksie het tussen mielie hibriede voorgekom. Die
neutraalbestandevesel- en suurbestandeveselinhoud het nie verskil tussen hibriede nie en
derhalwe kon dit nie gebruik word om voedingswaarde ofproduksiepotensiaal te beraam rue. Mielies is op die hardedeegstadium met of sonder die toediening van 'n melksuurbakterieseinokulant
in laboratoriumsilos en 210 liter dromme ingekui!. Die toediening van die inokulant
het geen invloed op tempo van pH-daling ofproduksie van melksuur gehad nie. Die inname en
groei van SA Vleismerino lammers wat 'n dieet bestaande uit 60% kontrole of inokulant
behandelde mieliekuilvoer ontvang het, is bepaa!. Die gemiddelde daaglikse toename van
lammers was 239 ± 26 and 255 ± 44 g/dag vir die kontrole en inokulant mieliekuilvoer dieet
respektiewelik. Alhoewel die laboratoriumstudie weinig verskille tussen die kontrole en die
geYnokuleerde mieliekuilvoer getoon het, het lammers geneig om meer van die geYnokuleerde
mieliekuilvoer in te neem. In die tweede studie met mieliekuilvoer is die effek van toediening
van 'n melksuurbakteriese-inokulant met ensieme, op die ferrnentasiedinamika tydens inkuiling,
die aerobiese stabiliteit van mieliekuilvoer asook die inname, melkproduksie en
melksamestelling van Jersey koeie bepaa!. Die inokulant het nie die tempo van pH daling en
produksie van melksuurverhoog nie en beide kontrole en geYnokuleerde mieliekuilvoerwas goed
gepreserveer. Die toediening van die inokulant tot mieliekuilvoer het die smaaklikheid, inname
en die aerobiese stabiliteit van mieliekuilvoer verhoog in vergeiyking met kontrole
mieliekuilvoer. Melkproduksie, melksamestelling, liggaamsmassa en kondisiepunt van Jersey
koeie is nie betekenisvol beYnvloed deur die toediening van die inokulant tot mieliekuilvoer nie.
Die effek van die toediening van 'n ensiem bevattende melksuurbakteriese-inokulant tot groot
rondebaal hawer (Avena sativa, cv Cederberg) kuilvoer op die samestelling van kuilvoer,
kuilvoerinname, melkproduksie en melksamestelling van Jersey koeie is bepaa!. Die gewas is
gesny op die blomstadium, verwelk en as rondebaalkuilvoer gepreserveer. Die inokulant, Sil-All,
is tydens die baalproses toegedien op die helfte van die bale. Kuilvoere is aan Jersey koeie gevoer
in 'n inname en melkproduksiestudie. Beide die kontrole en geYnokuleerde hawerkuilvoer was
goed gepreserveer. Die bottersuurinhoud van geYnokuleerde hawerkuilvoer was laer as die van
die kontrole hawerkuilvoer. Koeie wat geYnokuleerde hawerkuilvoer gevoer is het meer (P=0.05)
melk (17.7 kg/dag) geproduseer as koeie wat kontrole hawerkuilvoer ontvang het (16.7 kg/dag).
Die toediening van 'n melksuurbakteriese-inokulant het kuilvoer kwaliteit en diereproduksie
verbeter.
Hierdie studie wys duidelike verskille uit tussen kuilvoer wat in bunkersilos onder kommersiele
toestande ingekuil is, en kuilvoer wat in laboratoriumsilos gemaak is. Wanneer die effek van
kuilvoerbymiddels op die aerobiese stabiliteit van kuilvoer bepaal word behoort finale evaluasie
gedoen te word op kuilvoer gemaak in bunkersilos soos onder plaastoestande plaasvind.
Evaluasie van kuilvoerbymiddels behoort inname en diereproduksiestudies in te sluit.
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