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Physiochemical controls on the formation and stability of atacamite in the soil surrounding the Spektakel mine, Northern Cape Province, South AfricaLe Roux, Stephan Gerhard 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: The Northern Cape Province of South Africa has played host to numerous mining activities for over a century. To date, most of the mining activity has ceased, leaving the area laden with derelict mine sites and unlined tailings dumps. One such site is the Spektakel mine situated to the west of the town of Springbok. The unlined copper and sulphide rich tailings at the site have the potential to leach elevated concentrations of copper and acidic water into the Buffels River downslope of the site. This poses a threat to the surrounding communities that rely mainly on the river to supply water for drinking, livestock and irrigation.
The soil surrounding the tailings dumps was characterised in terms of its mineralogical and chemical properties. The results indicate that the soil contains elevated concentrations of Cu2+, which is bound in the soil in the form of the secondary copper hydroxy mineral atacamite (Cu2(OH)3Cl). No other secondary copper minerals were identified at the site. Analysis of the solution present on the surface of the tailings dumps indicate that the tailings are the main source of the high Cu2+, Mg2+ and SO42- concentrations observed in the surrounding soils. As this solution migrates through the tailings dumps, into the soil, it accumulates Cl- through halite dissolution. The resulting acidic Cu2+, Mg2+, SO42- and Cl- solution reacts with the calcite in the soil, replacing it with atacamite.
To determine why only a copper chloride mineral formed in the sulphate rich environment a synthetic solution with the composition of a solution in equilibrium with the soil was evaporated, both in the presence and absence of calcite. The results indicate that when the solution comes into contact with calcite, atacamite immediately precipitated, removing the Cu2+ from the solution. In the absence of calcite Cu2+ remains conservative, accumulating in the solution without precipitating a copper sulphate mineral. This establishes that the elevated Mg2+ concentration of the solution induces the formation MgSO4 aqueous complexes that reduce the activity of free sulphate, thus restricting copper sulphate mineral formation.
The results from the soil characterization indicate that the atacamite stabilization mechanisms (circumneutral pH, high Cl- concentration and calcite) in the soil are diminishing. During sporadic rain events the acidic tailings solutions dissolve the calcite and temporarily reduce the Cl- concentration of the soil. To determine how these decreases will influence Cu2+ mobility in the soil, the stability of atacamite was tested by reducing the pH both in the presence and the absence of chloride. The results indicate that an elevated Cl- concentration and a pH > 6 stabilizes atacamite. A decrease in either of these parameters destabilizes atacamite and favours its dissolution. The study concludes that the current chemical conditions in the soil at Spektakel favour the stability of atacamite. However, continued sporadic rain events will reduce the Cl- concentration in the soil by increasing the SO42- concentration. This acidic solution will dissolve the calcite in the soil, thus reducing the buffering capacity of the soil, leading to the instability of atacamite, resulting in the leaching of large quantities of Cu2+ into the surrounding water bodies. / AFRIKAANSE OPSOMMING: Die mynbou bedryf was die ekonomiese dryfkrag van die Noord-Kaap Provinsie van Suid-Afrika vir meer as ‘n eeu. Die area was die gasheer vir ‘n verskeidenheid mynbou aktiwiteite tot die mynmaatskappye besluit het om mynproduksie te staak en die gebied te verlaat. Die mynmaatskappye het geen rehabilitasie aan die myne en mynhope verrig nie. Die verlate myne lê verspreid in die area met oop mynhope wat koper en ander swaar metale in die grond, sowel as in die water, na omliggende areas kan versprei. Een van dié verlate myne is die Spektakel myn 40 km wes van Springbok. Die mynhope by Spektakel kan moontlik koper en ander swaar metale in die Buffelsrivier, wat langs die myn verby loop, loog. Dit dien as ‘n bedreiging vir die omliggende gemeenskappe wat staatmaak op die water vir drinkwater en besproeiing.
Die grond rondom die mynhope was ge-analiseer om te bepaal hoe erg ‘n bedreiging die mynhope vir die omgewing is. Die resultate dui daarop dat die grond hoë konsentrasies Cu2+ bevat wat vasgebind is in die sekondêre koper mineral atakamiet (Cu2(OH)3Cl). Geen ander sekondêre koper minerale is in die grond geïdentifiseer. Die analise van die oplossing wat bo-op die mynhoop aangetref is dui aan dat dié oplossing suur en gekonsentreerd is t.o.v. Cu2+, Mg2+ en SO42-. Terwyl die oplossing deur die mynhoop migreer los dit haliet in die grond op wat Cl- tot die oplossing byvoeg. Wanneer hierdie suur en Cu2+, Mg2+, SO42- en Cl- ryke oplossing met die kalsiet in die grond reageer word die kalsiet vervang met atakamiet (Garrels en Stine, 1948).
Om vas te stel waarom slegs 'n koperchloried mineraal vorm in die sulfaat ryke grond was ‘n oplossing, met ‘n samestelling soortgelyk aan 'n oplossing in ewewig met die grond, verdamp in beide die teenwoordigheid en afwesigheid van kalsiet. Die resultate van die eksperiment dui daarop dat wanneer die oplossing in kontak kom met kalsiet atakamiet onmiddellik neerslaan en Cu2+ uit die oplossing verwyder. In die afwesigheid van kalsiet bly Cu2+ konserwatief in die oplossing; die Cu2+ hoop op in die oplossing en slaan nooit neer nie. Daar is vasgestel dat die verhoogde Mg2+ in die grondoplossing MgSO4 water komplekse vorm wat die aktiwiteit van SO42- verlaag en verhoed dat kopersulfaat minerale kan vorm.
Verdere navorsing dui aan dat die chemiese meganismes wat atakamiet in die grond stabiliseer besig is om te kwyn. Gedurende sporadiese reën buie word die kalsiet in die grond opgelos deur die suur mynhoop oplossings wat die pH van die grond verlaag. Die mynhoop oplossing verryk ook die grond t.o.v SO42- wat die Cl- konsentrasie verlaag. Om te bepaal hoe hierdie afname in Cl- konsentrasie en pH die migrasie van Cu2+ beïnvloed was atakamiet oplossbaarheid bepaal. Atakamiet was onderskeidelik geplaas in ‘n suiwer water en chloried oplossing tewyl die pH verlaag was om te bepaal hoe atakamiet oplos in elk van die oplossings. Die resultate dui aan dat 'n verhoogde Cl- konsentrasie en pH > 6 atakamiet stabiliseer. Die afname van beide hierdie veranderlikes het veroorsaak dat atakamiet makliker ontbind en Cu2+ vrystel.
Die gevolgtrekking van die studie is dat die huidige chemiese toestande in die grond by Spektakel gunstig is vir die stabiliteit van atakamiet. Met sporadiese reën buie neem die Cl- konsentrasie in die grond af en los kalsiet op. Hierdie afname in pH en Cl- konsentrasie maak atakamiet meer onstabiel wat gevolglik Cu2+ in die grond en water rondom Spektakel vrystel.
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Meat quality characteristics of the springbok (Antidorcas marsupialis)Kroucamp, Mariska 04 1900 (has links)
Thesis (MScVoedselwet)--University of Stellenbosch, 2004. / ENGLISH ABSTRACT: The objective of this investigation was to evaluate the effects of age (adult, sub-adult and lamb),
gender (male and female) and production region on the morphological characteristics of
springbok (Antidorcas marsupialis). In addition, the effects of the latter on the physical, chemical
and sensory quality of the M. longissimus dorsi (LD) muscle were determined. Where
applicable, correlations within the various physical and chemical attributes of the meat were
verified in the experiments. The sensory ratings of the meat were correlated with the data on the
physical and chemical attributes of the LD muscle, where applicable.
The mean live mass of male and female adult springbok differed significantly (p < 0.05)
and averaged 31.7 ± 0.70 and 28.3 ± 0.60 kg respectively. Gender had no significant effect on
the mean live mass of the sub-adult category. The mean dressing percentage of the males
(58.83 ± 0.53%) was noted to be significantly higher than that of the females (55.79 ± 0.50%).
The lambs (58.98 ± 1.07%) had the highest dressing percentage of all the age categories. An
increase in carcass measurements was noted with an increase in animal age. Gender did not
have a significant (p > 0.05) effect on the carcass measurements.
Inverse correlations were noted between pH24 and drip loss (r = -0.26, p < 0.01) and
cooking loss (r = -0.42, p < 0.0001) of the LD muscle. It was noted that stressed animals had a
significantly (p < 0.05) higher ultimate pH24 (6.30 ± 0.07), as observed in the meat originating
from the Caledon region and this meat consequently had a significantly (p < 0.05) lower cooking
loss (27.18 ± 0.62%) and drip loss (1.79 ± 0.08%). Meat shear force values ranged between
1.67 ± 0.05 and 2.67 ± 0.16 kg. 1.27 cm-1 diameter. Age-related effects on tenderness were
found to be minor in comparison to pH24 effects.
The females (3.13 ± 0.28%) were noted to have a significantly (p < 0.05) higher fat
content than the males (1.35 ± 0.08%). The adult (2.45 ± 0.26%) and sub-adult (2.50 ± 0.28%)
animals had a significantly higher fat content in comparison with the lambs (1.32 ± 0.11%). The
protein content of the springbok meat originating from the four production regions varied
between 18.80 ± 0.35 and 21.16 ± 0.51%. Gender had no significant effect on the protein
content, except for the meat originating from Rustfontein Nature Reserve where the females had
a significantly higher protein content. The two major amino acids noted for springbok LD muscle
were glutamic and aspartic acid. Phosphorous was the predominant mineral, followed by
potassium and calcium. Production region had a significant (p < 0.05) effect on both the amino
acid and mineral content of the meat. The saturated fatty acid (SFA) content of the LD muscle contributed 38.40 to 42.69% of
the total identified fatty acids. The poly-unsaturated fatty acid (PUFA) content (36.34 - 40.98%)
of the meat was very close to this range, meaning that optimal polyunsaturated to saturated
(P:S) ratios (0.96 - 1.18) were present. The effects of age and gender on the fatty acid
composition were minor in comparison with regional effects.
Warner-Bratzler Shear force (kg. 1.27 cm-1 diameter) values were inversely correlated
with the following sensory attributes: tenderness (r = -0.70, p < 0.01), residual tissue (r = -0.68,
p < 0.01) and sustained juiciness (r = -0.43, p < 0.05). Decreased acceptance of the meat was
noted with an increase in ultimate pH (pH24) from 5.4 to 5.8. As the ultimate pH of the meat
increased, the rankings for tenderness (r = -0.46, p < 0.05) and sustained juiciness (r = -0.54, p
< 0.05) decreased significantly. / AFRIKAANSE OPSOMMING: Die doel van hierdie ondersoek was om die invloed van ouderdom, geslag en produksie area op
die morfologiese eienskappe van springbok (Antidorcas marsupialis) te evalueer. Die effek van
laasgenoemde faktore op die fisiese, chemiese en sensoriese kwaliteit van die M. longissimus
dorsi (LD) is ook ondersoek. Korrelasies in die fisiese en chemiese eienskappe van die vleis is
bestudeer. Die resultate van die sintuiglike evaluering van die vleis is gekorreleer met die
fisiese en chemiese data van die LD spier, indien van toepassing.
Die gemiddelde gewig van die manlike (31.7 ± 0.70 kg) en vroulike (28.2 ± 0.60 kg) diere
het betekenisvol (p < 0.05) verskil. Geslag het geen betekenisvolle effek op die gemiddelde
gewig van die sub-volwasse diere getoon nie. Die gemiddelde uitslag persentasie van die
manlike diere (58.83 ± 0.53%) was betekenisvol (p < 0.05) hoër in vergelyking met die vroulike
diere (55.79 ± 0.50%). Met ‘n toename in ouderdom is ‘n toename in karkas metings
waargeneem. Geslag het geen effek op die karkas metings getoon nie.
Negatiewe korrelasies is genoteer tussen die finale pH (pH24) en drupverlies (r = -0.26, p
< 0.05) en tussen pH24 en kookverlies (r = -0.42, p < 0.0001) van die LD spier. Gestresde diere
van die Caledon area het ‘n betekenisvolle (p < 0.05) hoër pH24 (6.30 ± 0.07) getoon en
gevolglik ‘n laer (p < 0.05) kookverlies (27.18 ± 0.62%) en drupverlies (1.79 ± 0.08%). Die
skeurkrag waardes van die LD spier het gewissel van 1.67 ± 0.05 tot 2.67 ± 0.16 kg. 1.27 cm-1
diameter. Die effek van ouderdom op taaiheid was klein in vergelyking met die effek van pH24.
Die vroulike diere (3.13 ± 0.28%) het ‘n hoër (p < 0.05) vetinhoud as die manlike diere
(1.35 ± 0.08%) getoon. Die volwasse (2.45 ± 0.26%) en sub-volwasse (2.50 ± 0.28%) diere se
vetinhoud was hoër as die van die lammers (1.32 ± 0.11%). The proteininhoud het gewissel van
18.80 ± 0.35 tot 21.16 ± 0.51%. Geslag het geen effek (p > 0.05) getoon op die proteieninhoud,
behalwe vir die vleis van die Rustfontein Natuur Reservaat. Glutamien en aspartien suur was
kwantitatief die belangrikste aminosure. Fosfor was die belangrikste mineraal, gevolg deur
kalium en kalsium. Produksie area het ‘n betekenisvolle (p < 0.05) effek op die aminosuur en
mineraalinhoud getoon.
Die versadigde vetsuur (SFA) inhoud het gewissel van 38.40 tot 42.69% van die totale
geïdentifiseerde vetsure. Die poli-onversadigde vetsuur (PUFA) inhoud het gewissel van 36.34
tot 40.98% en daarom is optimale poli-onversadigde tot versadigde (P:S) verhoudings (0.96 -
1.18) genoteer. Die effek van ouderdom en geslag op die vetsuursamestelling was minimaal in vergelyking met
die effek van produksie-area.
Warner-Bratzler skeurkrag (kg. 1.27 cm-1 diameter) waardes was negatief gekorreleer
met die volgende sensoriese eienskappe: taaiheid (r = -0.70, p < 0.01), residuweefsel (r = -0.68,
p < 0.01) en volgehoue sappigheid (r = -0.43, p < 0.05). Daar is ‘n afname in die
aanvaarbaarheid van die vleis waargeneem met ‘n toename in pH24 van 5.4 tot 5.8. Met ‘n
toename in pH24, het die taaiheid (r = -0.46, p < 0.05) en volgehoue sappigheid (r = -0.54, p <
0.05) van die vleis afgeneem
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Investigation into selected parameters required to develop a sustainable Namibian game meat industryVan Schalkwyk, Diana Louisa 03 1900 (has links)
Thesis (PhD (Food Sc))--Stellenbosch University, 2011. / ENGLISH ABSTRACT: The wildlife industry in Namibia has shown tremendous growth over the past
decades and is currently the only extensive production system in Namibia that is
expanding. Harvesting game for the purpose of meat production is a viable option
since there is a worldwide demand for healthy and high quality proteins.
The main objective of the dissertation was to investigate selected parameters
required to develop a sustainable Namibian game meat industry. The major species
suitable for commercial harvesting operations are springbok (Antidorcas marsupialis
– Zimmerman, 1780), gemsbok (Oryx gazella – Linnaeus, 1785), kudu (Tragelaphus
strepsiceros – Pallas, 1766), mountain zebra (Equus zebra hartmannae – Linnaeus,
1758) and red hartebeest (Alcelaphus buselaphus caama – Pallas, 1766). Eland
(Tragelaphus oryx – Pallas, 1766) could be considered as a suitable species,
although the numbers of animals that can be harvested during an operation are
limited.
This study demonstrated that gender influenced live weight of springbok, kudu
and red hartebeest. Gender also influenced carcass weights for springbok,
gemsbok, kudu and red hartebeest, but not for eland, while dressing percentage did
not differ between gender for springbok, gemsbok, kudu and red hartebeest.
Although there were some statistical differences in the chemical composition
of the various muscles from the different species (Mm. biceps femoris, infraspinatus,
longissimus dorsi, semimembranosus, semitendinosus and supraspinatus), it is
doubtful whether consumers would be able to distinguish between these.
Discriminant analysis could not differentiate among the different muscle
groups for springbok and gemsbok. A differentiation was, however, revealed among
the various muscles for red hartebeest.
During the investigation on the influence of season and gender on the carcass
yields and meat quality characteristics of kudu and red hartebeest, dressing
percentage was affected by season, but not by gender. Muscle colour differed
significantly between seasons.
Results from this study showed that male eland contained more saturated
fatty acids than females, but no gender differences were observed for polyunsaturated
fatty acids. Hides of gemsbok, kudu and red hartebeest contributed 6 – 7% of live weight,
while the skin of springbok contributed 4 – 5% of live weight. Comparisons of offal
items among species showed significant differences for all offal items, except for
intestines.
Retail cuts showed significant species difference for rump, topside, silverside
and sinews. No significant species differences were observed for thick flank and
bolo. Significant gender differences were observed for silverside. No interactions
between species and gender were found for the different retail cuts from gemsbok
and kudu.
Microbiological counts of game meat, chilled for 6 weeks and frozen for 12
months, respectively, were found to be within acceptable limits as prescribed by the
South African retail market.
Differences in physico-chemical and microbiological properties were observed
among salami from different game species. The springbok salami was found to be
microbiologically unstable. The main characteristics observed while tasting the
salami from springbok, gemsbok, kudu and zebra were a distinctive smoky, salty,
pepper and salami flavour combined with a smoky, salami aroma. Game flavour did
not feature as strong during the sensory analyses.
Sustainable utilization of game for commercial meat production has the
potential to increase earnings to beneficiaries in the wildlife sector. Results from this
study contributed knowledge which can be utilized to develop the Namibian game
meat industry. / AFRIKAANSE OPSOMMING: Die wildsbedryf in Namibië het die afgelope dekades buitengewone groei getoon en
is huidiglik die enigste ekstensiewe produksie-sisteem wat in Namibië uitbrei. Die
oes van wild is ʼn voordelige opsie, aangesien daar wêreldwyd ʼn aanvraag is na
gesonde en hoë kwaliteit proteïene.
Die hoofdoelwit van hierdie dissertasie was die loods van ʼn ondersoek na
geselekteerde aspekte wat benodig word om die Namibiese wildsvleisbedryf te
ontwikkel. Die belangrikste spesies geïdentifiseer as geskik vir kommersiële oes, is
springbok (Antidorcas marsupialis – Zimmerman, 1780), gemsbok (Oryx gazella –
Linnaeus, 1785), koedoe (Tragelaphus strepsiceros – Pallas, 1766), berg sebra
(Equus zebra hartmannae – Linnaeus, 1758) en rooihartbees (Alcelaphus
buselaphus caama – Pallas, 1766). Eland (Tragelaphus oryx – Pallas, 1766) is ook
ʼn geskikte spesies, maar die hoeveelhede wat op een slag geoes kan word, is
beperk.
Hierdie studie het gedemonstreer dat geslag ʼn invloed op die lewendige
gewig van springbok, koedoe en rooihartbees het. Geslag het ook ʼn invloed gehad
op karkasgewigte van springbok, gemsbok, koedoe en rooihartbees, maar geen
invloed op die karkasgewig van eland nie, terwyl uitslagpersentasie geensins
geslagsverskille getoon het vir springbok, gemsbok, koedoe of rooihartbees nie.
Nieteenstaande statistiese verskille in die chemiese samestelling van die
verskillende spiere van die onderskeie spesies (Mm. biceps femoris, infraspinatus,
longissimus dorsi, semimembranosus, semitendinosus en supraspinatus), is dit te
betwyfel of verbruikers ʼn onderskeid sal kan tref tussen die spiere.
Diskriminant-analise kon nie verskille uitwys tussen die verskillende groepe
spiere van springbok en gemsbok nie. Verskille was egter te bespeur tussen
verskillende spiere van die rooihartbees.
Gedurende hierdie ondersoek is die invloed van seisoen en geslag op die
karkasopbrengs en vleiskwaliteit van koedoe en rooihartbees ondersoek.
Uitslagpersentasie is beïnvloed deur seisoen, maar nie deur geslag nie. Kleur het
betekenisvol verskil tussen seisoene.
Resultate van die studie het getoon dat elandbulle meer versadigde vetsure
het as koeie, maar dat geen verskille vir geslag gevind is vir poli-onversadigde
vetsure nie. Gemsbok-, koedoe - en rooihartbeesvelle het 6 – 7% bygedra tot die
lewendige gewig, terwyl die vel van die springbok 4 – 5% bygedra het. Vergelykings
van afvalopbrengs tussen spesies het verskille uitgewys ten opsigte van al die items,
behalwe die ingewande.
Kleinhandelsnitte het betekenisvolle verskille getoon vir die kruis, binneboud,
dy en senings. Geen betekenisvolle spesies verskille is opgemerk vir die diklies en
bolo nie. Die dy het betekenisvolle verskille tussen geslagte getoon. Geen
interaksie tussen spesies en geslag is opgemerk vir die verskillende
kleinhandelsnitte van gemsbok en koedoe nie.
Mikrobiologiese tellings vir wildsvleis, verkoel vir 6 weke en gevries vir 12
maande, onderskeidelik, het voldoen aan die aanvaarbare vlakke soos voorgeskryf
deur die Suid-Afrikaanse kleinhandelsmark.
Verskille in fisiese, chemiese en mikrobiologiese kwaliteite was opgemerk vir
die salami van die verskillende spesies. Springbok salami was mikrobiologies
onstabiel. Die belangrikste karaktereienskappe bemerk tydens die proe van die
salami vervaardig van springbok-, gemsbok- , koedoe - en sebravleis, was ʼn
oorheersende rook-, sout-, peper- en salamigeur, gekombineer met ʼn rook- en
salami aroma. Wildsvleisgeur het nie sterk na vore gekom tydens die sensoriese
analise, nie.
Die volhoubare gebruik van wild vir kommersiële vleisproduksie het die
potensiaal om inkomste vir belangegroepe in die wildsektor te verhoog. Resultate
van hierdie studie het kennis uitgebrei wat gebruik kan word om die
wildsvleisindustrie in Namibië te ontwikkel.
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Improving the meat quality of Blesbok (Damaliscus Dorcas Phillipsi) and Springbok (Antidorcas Marsupialis) through enhancement with inorganic saltsDu Buisson, Petro-Mare 03 1900 (has links)
Thesis (Msc (Animal Sciences))--University of Stellenbosch, 2006. / This research had a dual purpose, firstly to study five muscles (M. biceps femoris, M.
longissimus et lumborum, M. rectus femoris, M. semitendinosus and M. supraspinatus) of the
blesbok (Damaliscus dorcas phillipsi) and springbok (Antidorcas marsupialis) in terms of the
physical and chemical meat quality characteristics, and secondly, to investigate the effects of
inorganic salt enhancement on the physical, chemical and sensory meat quality
characteristics.
The muscles differed significantly for the investigated characteristics, with the exception of a*
value, chroma, and ash percentage, which did not differ in either blesbok or springbok.
Furthermore, no muscle differences were found in fat percentage in blesbok or protein
percentage in springbok meat. Muscle differences were found in the stearic acid (C18:0)
composition, the percentage saturated fatty acids (SF) and the polyunsaturated: saturated
fatty acid ratio (P:S) of the blesbok. Only linoleic acid (C18:2) as a percentage of the total
fatty acids differed significantly amongst the springbok muscles.
The shear force values were found to be significantly lower in the enhanced samples
(blesbok: 25.16 vs. 43.75 N/1.27cm; and springbok: 23.96 vs. 34.89 N/1.27cm), which means
that the enhanced muscles were more tender.
The enhanced muscles of both species were found to have lower values for all investigated
colour characteristics. Moisture values were found to be higher in all the enhanced muscles
(blesbok: 76.53% vs. 74.38%; and springbok: 75.34% vs. 73.37%). The lower fat and protein
contents of the enhanced muscles can possibly be ascribed to a diluent effect caused by the
water added as part of the inorganic salt injection (blesbok: fat, 1.86% vs. 2.22%, protein,
19.61% vs. 21.67%; and springbok: fat, 1.84% vs. 2.14%, protein, 21.23% vs. 23.26%).
Major changes in the mineral contents were expected between the two treatments and in both
species the enhanced muscles had higher phosphorus, potassium, sodium and copper
values, but lower magnesium, iron and zinc levels than the untreated muscles.
Analytical sensory analyses were performed on the M. biceps femoris and M. longissimus et
lumborum samples of both species. Tenderness and juiciness were significantly higher in the
enhanced muscles. Although salty taste was significantly higher in the enhanced muscles
due to the addition of the inorganic salt solution, it remained acceptable.
Analytical and consumer sensory analyses were performed on blesbok and springbok M.
longissimus et lumborum samples prepared in a stock mixture. The outcome of the analytical
sensory analysis was similar to the analytical results reported above. The consumer sensory analysis showed that consumers preferred the enhanced blesbok and springbok muscles,
with a significant improvement in consumers’ likeness of enhanced vs. untreated meat.
This study provides important insights into the muscle differences of two of the most common
game species currently utilised in South African meat production. It confirms that both
species can be marketed as a low fat organic red meat source well capable of filling the
modern consumer’s nutritional and health needs. It also shows that enhancing game meat
with an inorganic salt solution might be a very useful processing tool to use to further game
meat acceptability in terms of tenderness and juiciness as game meat is often experienced as
being dry and less tender because of its lower fat content and the use of incorrect preparation
techniques.
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Characterization of testes and functional evaluation of cryopreserved epididymal spermatozoa from three South African antelope speciesChatiza, Fungayi Primrose 14 January 2014 (has links)
Ph.D. (Zoology) / This project involves a detailed study of three South African antelope species, springbok, impala and blesbok. The study investigates the origins of sperm in terms of testicular histology and subsequently the major storage organ, the cauda epididymis. Sperm of these species were characterized in terms of their quality (morphology, motility, vitality characteristics among others and their physiology: when exposed to different media and cryopreservation protocols. Finally sperm fertilization biology of the three species and evaluation of fertilization and developmental success when using homologous and heterologous oocytes (relative comparison) were assessed. Cauda epididymal spermatozoa was recovered post-mortem from the testes of culled springbok (n =38); impala (n =26) and blesbok (n =42) during winter months in South Africa and cryopreserved in a Tris-fructose-citric acid extender (Biladyl) supplemented with 20% egg yolk and 7% glycerol under field conditions. Longevity of sperm was assessed in Tris and Citrate extenders and modified Tyrode lactate in vitro fertilization (IVF) media. Oocytes were collected from the ovaries of domestic cows (n =165), springbok (n = 72) and blesbok (n = 42) and matured in domestic cattle M199 maturation media supplemented with 10% FCS, 10IJg/mi LH, 10IJg/mi FSH and antibiotics. Heterologous (zona intact and zona free) and homologous fertilization was carried using a domestic cattle IVF protocol. Results were analysed using SPSS version 18.0 (Statcon, South Africa). Interspecies comparisons were made using parametric tests: paired t-test for the freezing effect, one-way analysis of variance (ANOVA), Mixed between-within subjects ANOVA for longevity, Non Parametric test for motility characteristics and least squares ANOVA for...
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The economics of converting a sheep farm into a springbuck (Antidorcas marsupialis) ranch in Graaff-Reinet: a simulation analysisDlamini, Thula Sizwe January 2012 (has links)
In Graaff-Reinet, domestic livestock farming and springbuck ranching are similar in that they both rely on the rangeland for their sustainability. However, as a consequence of repeated monotonous domestic livestock farming, resulting in compromised biological productivity and diversity, the rangelands have disintegrated. This, unfortunately, has placed the future sustainability of these rangelands and the livelihoods of the local people in an indeterminate state. In recent years, there has been an increasing interest in springbuck ranching for meat production as an alternative to domestic livestock farming in the area following (a) fears of worsening environmental challenges; (b) declining profitability in commercial domestic livestock farming and; (c) growing calls for the sustainable use of these rangelands for the benefit of future generations. The springbuck has emerged as a credible alternative to utilising the rangelands - as opposed to sheep - because of its promise to addressing the above challenges. This is in an attempt to tap into the multitude of benefits that the springbuck possesses (by virtue of being part of the natural capital of the area) that have a potential towards restoring ecological integrity by extenuating some of the detrimental effects of sheep farming on the rangelands and presenting opportunities for diversifying incomes. Yet, despite the general increase in interest, a resistance towards the uptake of springbuck ranching for meat production exists. The main contention is that springbuck meat production cannot out-perform the economic returns of wool sheep farming. This study attempts to address these concerns by investigating the profitability and economic sustainability of converting a sheep farm into a springbuck ranch in Graaff-Reinet. The study uses stochastic simulation to estimate the probability distribution of some key output variables, namely: net cash income, ending cash balance, real net worth and the net present value (NPV) in evaluating the profitability of converting a 5 000ha sheep-dominated farm into a springbuck-dominated ranch under three alternative scenarios. The use of stochastic simulation allows for the incorporation of downside risk associated with the production and marketing of wool, mutton and springbuck meat. The study uses stochastic prices and yields to calculate net returns variability. Incorporating scenario analysis helped to evaluate how alternative wool sheep-dominated and springbuck-dominated combinations would perform based on the probable outcomes of different assumptions in the various scenarios. By applying stochastic efficiency with respect to a function (SERF) criterion to the simulated NPVs, this study compares the profitability of alternative scenarios based on various risk aversion coefficients. The study finds that converting a 5 000ha wool sheep dominated farm into a springbuck dominated ranch could potentially be a more profitable investment than wool sheep farming over a 15 year planning horizon, in Graaff-Reinet. The SERF results indicate that for all scenarios tested, the best strategy of converting a wool sheep dominated farm into a springbuck ranch would be one which comprise a combination of 70% springbuck, 20% mutton and 10% wool production as the likely profitable enterprise mix. Using economic sustainability analysis, the study reveals that because of low costs in springbuck ranching, springbuck meat production enterprises are most likely to be more financially sustainable than wool sheep-dominated enterprises. This suggests that rangeland owners may be better off converting their wool sheep-dominated farms into springbuck-dominated ranches. Thus, as the call for more environmentally benign rangeland utilising economic-ecological systems intensifies, rangeland owners in the Eastern Cape Karoo have a practicable option. At the very least, there exists an option to broaden their incomes whilst promoting ecological restoration with springbuck meat production.
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