The objective of this trial was to evaluate the effect of a multi-strain probiotic on serum concentrations of selected metabolites in young calves. Holstein heifers (n = 112) from a commercial dairy were enrolled within 48 h of birth and placed into individual hutches. Calves were weaned at 60 d of age and remained in their hutches until 90 d of age, when they were moved to group housing. Calves were placed into 2 treatment groups: 1) control and 2) B. subtilis, B. lichenformis, L. animalis, and P. freudenreichii probiotic (Bovamine Dairy Plus, Chr. Hansen, Milwaukee, WI). Control calves received 0.5 g of lactose in milk once daily until weaning and 0.75 g in grain thereafter. Treatment calves received 0.5 g (1.1 × 10^10 cfu/g) probiotic in milk once daily until weaning and 0.75 g (1.65 × 1010 cfu/g) probiotic in grain thereafter. Jugular blood samples (6 mL) were collected at 14, 25, 45, 63, 77, 120, and 180 d of age for the determination of serum β hydroxy-butyrate (BHB), plasma glucose, non-esterified fatty acid (NEFA), total free amino acids (TFAA), blood urea nitrogen (BUN), and tumor necrosis factor-α (TNF). Data were analyzed as a mixed linear model to determine the fixed effects of treatment, day, and their interaction and also the random effect of calf. Single degree of freedom contrasts were used to evaluate the effect of phase (pre- vs. post-weaning) and the interaction of treatment with phase. Concentrations of BHB increased throughout the 180 d of the study and were greater (P < 0.001) in the post-weaning (661 μM) vs. pre- weaning (240 μM) phase and greater for the probiotic-treated calves in the post-weaning phase only (treatment × phase, P < 0.001). Glucose concentrations were greater (P < 0.001) for the pre-weaning (88.0 mg/dL) vs. post-weaning (81.1 mg/dL) phase and greater for calves receiving probiotics in the pre-weaning phase only (Treatment × phase, P < 0.01). Non- esterified fatty acid (NEFA) concentrations were greater (P < 0.001) in the pre-weaning vs. post-weaning phase and were greater in calves not receiving probiotics (treatment × phase, P = 0.0036).Serum TFAA concentrations were greater (P < 0.001) in the pre-weaning (3.37 mM) vs. post-weaning (3.03 mM) phase and greater for probiotic-treated vs. control calves (3.22 mM vs. 3.11 mM; P < 0.001). Concentrations of BUN were greater (P ≤ 0.001) in the post-weaning vs. preweaning phase and were higher for probiotic treated calves vs. control in the post-weaning phase (P < 0.001). Tumor necrosis factor-α (TNF) concentrations were affected by treatment (P< .001). Calves that received probiotic supplementation had lower TNF concentrations on day 63 of life when compared to control calves on day 63 of life. Data suggest that nutrient metabolism and ruminal development were enhanced by feeding a multi-strain probiotic.

The increasing dependence on amphibian captive breeding programs to support at-risk populations has led to growth in the application of assisted reproductive technologies (ART) to aid with the management of decreasing population density and genetic diversity. Already the integration of ART within these programs has led to monumental successes and shows great promise as a means to augment amphibian breeding efforts when natural breeding has low success. The focus of this project was to continue the optimization of ART to aid in making these technologies more widely applicable. Specific objectives include developing a framework that can be used to standardize follicular grading of oocytes through ultrasound assessments, demonstrating how advantageous routine sonography assessments are in providing insight into the female reproductive cycle in captive amphibians, and determining the differences in offspring growth and development between Ambystoma tigrinum larvae produced through in-vitro fertilization with either freshly collected or frozen-thawed sperm.

Thesis (MscAgric (Animal Sciences))--University of Stellenbosch, 2006. / The development of basic husbandry techniques and determining basic performance parameters are among the first steps towards culturing a new species. Silver kob, Argyrosomus inodorus, is a large Sciaenid and endemic to South Africa and Namibia and has been selected as a candidate aquaculture species. However, the proposed culture raises many questions, with two of them being the adaptability to captive conditions and product quality in the captive raised fish. To address these, trials were set up with eighty-three silver kob, divided into three ponds and fed three different diets. The effects of the diet on performance and quality were determined over a nine month trial period. The fish fed the pilchard diet adapted faster to the captive conditions than the fish fed the artificial diets. The growth of these fish were also markedly better than that of the fish fed the artificial diets, although after the adaptation period, the growth rate of the fish fed the artificial diets surpassed that of the fish fed the pilchards. Fifteen fish, five from each treatment were sacrificed and compared on a chemical and sensory level to wild-caught fish (control, n=6). Differences (p≤0.05) were noted in the total lipid content and fatty acid composition between the fish fed the different diets and the control. Sensory analysis revealed that the fish fed pilchards differed (p≤0.05) from the other groups by having an undesirable odour and flavour. The body partitioning and the proximate chemical composition of silver kob were determined. The length-weight relationship for silver kob raised in captivity was determined and a b-value of 3.32 was obtained, which indicates allometric growth with the fish becoming more rotund as their length increases. The results of these trials indicates that silver kob, A. inodorus adapts in captive conditions. The final product also compares favourably to wild-caught fish. The use of digital image analysis as a method of determining fish condition was also assessed with promising results for future application in research and production systems.

Thesis (MScAgric)--University of Stellenbosch, 2004. / ENGLISH ABSTRACT: The objective of this study was to determine the effect of extrusion, as a method of heat treatment, on the dry matter (DM) and crude protein (CP) degradability parameters of various vegetable protein sources commonly used in the Western Cape Province, South Africa. The feedstuffs used were lupins (LUP), full fat soybeans (SB), full fat canola seeds (FCS), soybean meal (SBM), canola meal (CM) and sunflower meal (SFM). In the first trial, the degradability parameters were determined according to an in sacco degradability procedure. Four non-lactating Holstein cows, fitted with rumen cannulae, were used in the trial and all cows received the same basal lactation diet. The samples were incubated in dacron bags and bags were removed at intervals of 0, 2, 4, 8, 16, 24 and 48 hours. Dry matter and CP disappearance values were determined and fitted to a onecompartment model by means of an iterative least-square procedure in order to determine the DM and CP degradability parameters. Results indicated that extrusion significantly lowered the effective degradability of the DM-fraction (20.1% on average) of all the feedstuffs, except LUP, and the effective degradability of CP in all the raw materials (27% on average). The second trial was an in vitro degradability trial that ran parallel with the in sacco degradability trial and was done with the aid of a DaisyII Incubator (ANKOM Technology Corp., Fairport, NY). The same feedstuffs were tested in both trials. A composited sample of rumen liquor from two of the cows used in the in sacco trial was used for in vitro incubation of the samples. The data obtained in this trial were analyzed in a similar way to that of the in sacco trial. Due to a limited amount of residue left after incubation, CP disappearance could not be calculated at each time interval for SB and SBM in the in vitro trial. In this case, actual disappearance values after 8h were used to compare treatments. Extrusion significantly lowered the effective degradability (as determined in vitro) of DM in all the feedstuffs tested (16.8% on average), as well as the effective degradability of CP in LUP, FCS, CM and SFM (21.8% on average). A comparison of the actual disappearance values after 8 hours incubation indicated that extrusion also lowered the rate of CP disappearance for SB and SBM. The values obtained in the in vitro trial and those from the in sacco trial, for the same feedstuffs, were compared. It appeared as if the in vitro determined values were overestimations of the in sacco determined values. A regression analysis showed a high correlation between the actual in vitro CP disappearance values after 8h incubation and in sacco determined effective degradability values. The third part of this study was a set of chemical analysis to determine the effect of extrusion on certain nitrogen fractions of the feedstuffs tested in the above mentioned trials. Solubility in a mineral buffer solution was determined to estimate the potential rumen degradability of the protein. The buffer insoluble nitrogen (BIN) fraction of all the feedstuffs, except FCS, was significantly increased by extrusion. Extrusion lowered the acid detergent insoluble nitrogen (ADIN) content of all feedstuffs, except FCS, which could imply that the temperature reached during extrusion (115°C - 120°C) was not high enough to cause damage to the protein. The neutral detergent insoluble nitrogen (NDIN) fraction of extruded SB, SBM, CM and SFM was significantly higher than that of the raw feedstuffs. Extrusion left the NDIN-fraction of FCS and LUP unaltered. Comparison of the NDIN : ADIN ratio of extruded with that of the raw feedstuffs provided reason to believe that extrusion had a positive effect on all feedstuffs (except FCS). Extrusion appears to be a useful method to decrease rumen degradation of vegetable protein sources, without causing heat damage. Furthermore, this means that protein sources of which the use have been limited due to its high rumen degradable protein (RDP) content, could be included in diets at higher levels following extrusion. The protein sources mentioned are also good sources of energy and the combination of energy and rumen undegradable protein (RUP) in the diet of the high-producing dairy cow could only be beneficial. / AFRIKAANSE OPSOMMING: Die doel van hierdie studie was om die effek van ekstrusie op die droëmateriaal (DM) en ruproteïen (RP)-degradeerbaarheidsparameters van verskeie plantaardige proteïenbronne wat algemeen in die Wes-Kaap (RSA), gebruik word, te bepaal. Ekstrusie is ‘n metode van hitteprosessering wat algemeen gebruik word deur plaaslike en internasionale veevoervervaardigers. Die volgende grondstowwe is geëvalueer: lupiene, volvet sojabone, volvet canolasaad, sojaboon-oliekoekmeel, canola-oliekoekmeel en sonneblom-oliekoekmeel. In die eerste proef is die degradeerbaarheidsparameters met behulp van ‘n in sacco studie bepaal. Vier droë Holstein koeie met rumen kannulas is in die studie gebruik en al vier koeie het dieselfde basale dieet ontvang. Monsters is in dacronsakkies geïnkubeer en die sakkies is uit die rumen verwyder na onderskeidelik 0, 2, 4, 8, 16, 24 en 48 uur intervalle. Die waardes van DM- en RP- verdwyning is bereken en dan met ‘n iteratiewe kleinste kwadraat prosedure op ‘n een-kompartement model gepas om die in sacco DM- en RPdegradeerbaarheidsparameters te bepaal. Die resultate van die studie het getoon dat ekstrusie die effektiewe degradeerbaarheid van die DM-fraksie van al die grondstowwe, behalwe lupiene, betekenisvol verlaag het (met gemiddeld 20.1%), asook die effektiewe degradeerbaarheid van die RP-fraksie van al die grondstowwe (met gemiddeld 27%). Die tweede proef was ‘n in vitro-degradeerbaarheidsstudie wat met behulp van ‘n ANKOM DaisyII Inkubeerder uitgevoer is en wat parallel met die in sacco-studie gedoen is. Dieselfde grondstowwe is in beide proewe geëvalueer. ‘n Saamgestelde monster van die rumenvloeistof van twee van die koeie wat vir die in sacco-studie gebruik is, is gebruik vir die in vitro-inkubasie van die monsters. Data-verwerking is op ‘n soortgelyke wyse as dié van die in sacco-studie uitgevoer. As gevolg van ‘n beperkte hoeveelheid residu na afloop van die inkubasies, kon die RP-verdwyning vir volvet sojabone en sojaboon oliekoekmeel nie bereken word nie. In hierdie geval is waargenome verdwyningswaardes na 8h gebruik om behandelings te vergelyk. Hierdie studie het getoon dat ekstrusie die effektiewe degradeerbaarheid van DM (soos in vitro bepaal) in al die getoetste grondstowwe betekenisvol verlaag het (met gemiddeld 16.8%). Die effektiewe degradeerbaarheid van RP in lupiene, volvet canola saad, canola oliekoekmeel en sonneblom oliekoekmeel is ook betekenisvol verlaag (met gemiddeld 21.8%). ‘n Vergelyking van die oorspronklike verdwyningswaardes van volvet sojabone en sojaboon oliekoekmeel na ‘n inkubasieperiode van 8 ure het ook getoon dat ekstrusie die tempo van RP-verdwyning uit die rumen vertraag het. Die in sacco- en in vitro-bepaalde waardes vir elke grondstof is vergelyk en dit kom voor asof die in vitro-waardes oorskattings van die in sacco-waardes is. ‘n Regressie-analise het verder getoon dat daar ‘n hoë korrelasie was tussen die waargenome in vitro RPverdwyningswaardes na 8 ure inkubasie en die beraamde effektiewe degradeerbaarheid, soos in sacco bepaal. Die derde deel van die studie was ‘n stel chemiese analises wat uitgevoer is om die effek van ekstrusie op sekere stikstof (N)-fraksies van die grondstowwe, wat in bogenoemde proewe gebruik is, te bepaal. Die oplosbaarheid van N in ‘n mineraal-bufferoplossing kan gebruik word as aanduiding van die potensiële rumendegradeerbaarheid van die proteïen. Die bufferonoplosbare N-fraksie van al die grondstowwe (behalwe volvet canolasaad) is betekenisvol verlaag deur ekstrusie. Ekstrusie het ook die suur-onoplosbare N-fraksie (ADIN) van al die grondstowwe (behalwe volvet canolasaad) betekenisvol verlaag. Dit kan moontlik daarop dui dat die temperatuur wat tydens ekstrusie (115°C - 120°C) bereik is, nie hoog genoeg was om die proteïen in die grondstowwe te beskadig nie. Ekstrusie het die N-fraksie wat onoplosbaar was in ‘n neutrale oplossing (NDIN) betekenisvol verhoog in volvet sojabone, sojaboonoliekoekmeel, canola-oliekoekmeel en sonneblom-oliekoekmeel en dit onveranderd gelaat in lupiene en volvet canolasaad). Die verhouding van NDIN : ADIN van die geëkstrueerde grondstowwe is vergelyk met dié van die rou grondstowwe. Dit blyk dat ekstrusie wel ‘n positiewe effek op al die grondstowwe (behalwe volvet canolasaad) gehad het. Dit wil dus voorkom asof ekstrusie wel aangewend kan word om die rumendegradeerbaarheid van plantaardige proteïenbronne te verlaag sonder om die protein te beskadig. Dit kan daartoe lei dat proteïenbronne waarvan die gebruik voorheen beperk was as gevolg van die hoë rumen-degradeerbare proteïen-inhoud daarvan nou wel in rantsoene ingesluit kan word na die ekstrusie daarvan. Die proteïenbronne, soos genoem, is ook redelike bronne van energie en die kombinasie van energie en rumen nie-degradeerbare proteïen in die rantsoen van die hoog-produserende melkkoei kan slegs voordelig wees.

Thesis (MScAgric)--University of Stellenbosch, 2005. / ENGLISH ABSTRACT: Porcine somatotropin (pST) is a naturally occurring protein (hormone), secreted by the pituitary gland of young pigs and is one of the major growth regulating factors. High levels of pST is found in circulating blood of young animals, resulting in the partitioning of nutrients into lean tissue and bone growth. Supplying an exogenous source of pST should increase the deposition of lean muscle and bone and decrease the deposition of fat in the older (above 60 kg) pig. To ascertain whether pST would have a positive influence on production- and meat characteristics in the South African scenario for pigs slaughtered at a high bodymass, a trail was conducted. For group housed animals pST had no significant effect on the following parameters: feed intake, calculated cumulatively on a weekly basis, ADG, live weight, carcass weight, carcass length, ham length or chest depth, intramuscular fat area, muscle depth and colour measured with a Hennessey probe and waterbinding capacity. However, when the FCR of pigs in this investigation were calculated, there was a significant (p<0.05) influence by sex and pST detected. Boars converted their feed to live weight better than barrows and gilts from week ten onwards. Boars had an increased FCR when treated with pST. A significant increase was found in muscle area and a significant decrease in extra muscular (back fat) area of boars and barrows. A significant pST (p< 0.05) effect (3 mm reduction) was seen for backfat depth measured by the Hennessey probe and the intrascope. Porcine somatotropin significantly (p<0.05) increased the muscle area of the loin-cut for all animals. The area covered by subcutaneous fat of boars and barrows were significantly (P<0.05) reduced by pST treatment, with no effect detected for gilts (p>0.05). Porcine somatotropin treatment increased the muscle percentage and decreased the extramuscular fat percentage in such a way that the differences between sexes was reduced. Thus, more uniform fat-muscle distribution between carcasses was obtained by pST treatment. Control animals had a significantly higher pH24 than pST treated animals (P=0.049). Lower values were found for animals receiving pST for L* (p=0.016), a* (p=0.002) and b* (P=0.016). The effect on b* (yellow-blue range) in the M longissimus thoracis of pST treated animals showed slightly (but significantly) less yellow and more green compared to control animals (p=0.016). This combined with the lower L* values (brightness) indicates that pST treated animals had a significantly darker colour meat compared to the control animals. Individually housed animals showed no significant differences for the following characteristics: live weight, carcass weight, head, trotters, shoulder, middle back, middle belly, loin belly, thigh, fillet, carcass fat and kidney. Whereas pST caused a significantly lower percentage of the middle back of boars and barrows, but not in gilts, pST could only precipitate a lower percentage (11.18%) loin back of treated animals (p=0.026) v.s. control animals (12.05%). A trend (p>0.1) was detected for percentage bone in the middle back, with the pST treated (14.17% vs. 13.18%) animals having more bone than that of control animals. pST animals had a higher percentage (p=0.024) skin (5.04%) than the control animals (4.28%). This study shows that there is no negative effect of pST on meat quality characteristics and carcass composition, in fact there is less variation between carcasses obtained from different sexes treated with pST. The producer can bring heavier animals to the market with a reduced backfat percentage and a greater percentage meat with the help of pST. / AFRIKAANSE OPSOMMING: Vark somatotropien (pST) is ‘n natuurlike hormoon wat deur die pituitêre klier in die brein afgeskei word by klein varkies en is een van die belangrikste hormone betrokke by groei regulering. Hoë vlakke van pST kom voor in die bloed van jong varkies, dit veroorsaak dan die verspreiding van nutriente in die liggaam van die varkie sodat dit meer vleis en beengroei toon en minder vet deponeer. Namate die varkie volwasse word neem die bloedvlakke van pST af en begin die liggam meer vet deponeer ten koste van proteien groei, terselfde tyd begin die seksuele kenmerke ontwikkel. Die toediening van ‘n eksterne bron van pST behoort die groei van been en vleis te bevoordeel in ouer diere (bo 60 kg). Vir die doeleindes van die ondersoek wou ons bepaal of pST ‘n positewe effek het op groei en vleiskwaliteitseienskappe van varke wat in Suid Afrikaanse kondisies gebruik word en teen ’n hoër liggamsmassa as gewoonlik geslag word. Vir varke wat in groepe behuis was was daar geen effek op die volgende eienskappe nie: voer inname weekliks bepaa, gemiddelde daaglikse toename, liggaamsmassa, karkasgewig, karkas lengte, ham lengte, bors diepte, intrmuskulêre vet en spierdikte bepaal met ‘n Hennessey sonde asook waterbindigs vermoë. Bere het egter ’n beter voeromsettings faktor gehat as burge en soggies, maar as pST toegedien is het hulle voeromsettingsfaktor toegeneem. ’n Betekenisvolle (p<0.05) toename in spier area van alle diere, met ’n gesamentlike afname in onderhuidse vet area van bere en burge (nie soggies nie) is gevind. ’n Betekenisvolle afname (3 mm) in rugvetdikte is gevind by diere wat met pST behandel is. Hierdie effekte is so in die lewe gebring dat die verskil tussen die geslagte minder prominent is en karkasse meer uniform is. Betekenisvolle hoër pH24 waardes is gevind by kontrole diere as by pST behandelde diere (p=0.049). L* (p=0.016), a* (p=0.002) en b* (p=0.016) waardes was betekenisvol laer vir pST behandelde diere as vir kontrole diere. Die effek op b* waardes (geel-blou reeks) in die M. longissimus thoracis van behandelde diere was in so ‘n mate dat die vleis ietwat minder geel en meer groen was in vergelyking met die kontrole diere (p=0.016), saam met laer L* waardes (helderheid) is ‘n indikasie van ietwat donkerder vleis van behandelde diere. Individueel behuisde diere het geen betekenisvolle effek getoon vir die volgende parameters nie: liggamsgewig, karkasgewig, kop, voete, skouer, middel rug, middel maag, lende maag, dy, haas en niere. ‘n Betekenisvolle laer persentasie middel rug is gevind in bere en burge, maar nie vir soggies nie, maar in die lende rug is ‘n betekenisvolle effek gevind vir alle diere (11.8% vir pST en 12.05% vir kontroe , p=0.026). ‘n Neiging (p>0,1) is gesien vir die hoeveelheid been in die middle rug van diere behandel met pST (14.17% vs. 13.18%) Dier met pSt behandel het’n betekenisvol hoer persentasie vel as kontrole diere gehat (5.04% vs. 4.28%, p=0.024. Die resultate van die ondersoek bewys dat daar geen negatiewe effekte van pST op vleis- en karkaseienskappe is nie, daar is self minder variasie tussen karkasse van verskillende geslagte. Die boer kan swaarder diere bemark met minder rugvet en meer vleis met behulp van pST.

Thesis (MScAgric)--University of Stellenbosch, 2003. / ENGLISH ABSTRACT: Near infrared reflectance spectroscopy (NIRS) was evaluated as a tool to predict the chemical composition of ostrich meat, mutton and feedstuffs. Seventy-three calibrations were developed. NIRS analyses were conducted on an InfraAlyzer 500 spectrophotometer between 1100 and 2500 nm wavelengths. Near infrared reflectance calibrations were developed for (i) the proximate chemical composition of ostrich meat; (ii) the proximate chemical and mineral composition of mutton; (iii) the chemical composition and digestibility of lupins, full-fat canola and the determination of alkaloids in lupins; (iv) the chemical composition and digestibility of winter grains and maize; (v) the chemical composition and digestibility of cereal hay, cereal straw, wheat stubble and alfalfa-grass/hay mixtures. The chemical composition of different types of winter grain produced in the Western Cape area of South Africa, as well as the chemical composition and digestibility of winter grain hay and straw produced in a Mediterranean rainfall area were also determined. Near infrared reflectance spectrometry proved to be successful for the prediction of crude protein (CP) and fat in both animal species, as well as for ash and dry matter (DM) in freeze-dried mutton. Accurate calibrations were also developed for certain minerals (K, P, Na, Mg, Fe and Zn). Calibrations proved to be accurate for all the relevant chemical constituents in lupins, as well as the DM, CP and fat calibrations in full-fat canola. The alkaloid calibration showed potential although more samples should be included for a more accurate calibration. Winter grain calibrations were accurate for fat, acid detergent fibre (ADF), in vitro organic matter digestibility (IVOMD), lysine and methionine. All chemical composition calibrations of maize, except for ash, were accurate for future prediction. Chemical composition calibrations of wheat stubble and alfalfa-grass hay mixtures resulted in prediction with similar or slightly higher accuracy than calibrations reported in the literature. The calibrations developed for cereal hay and straw were not suitable for prediction purposes. Possible reasons were discussed to explain these inaccurate calibrations. Variation shown between different types of cereal grain (2-row barley, 6-row barley, oats, wheat and triticale) accentuated the need for the analysis of different batches of grain produced under different conditions for use in animal feed. The chemical composition and digestibility of winter grain straw and hay were also obtained. These values provide a database for calculation of inclusion levels of these feedstuffs in animal diets. These investigations showed the NIRS to be a successful and rapid tool for the prediction of the chemical composition of ostrich and lamb meat and locally produced feedstuffs. / AFRIKAANSE OPSOMMING: Naby infrarooi refleksie spektroskopie (NIRS) is geëvalueer as 'n metode om die chemiese samestelling van volstruis- en skaapvleis, asook voedingsgewasse te voorspel. Drie en sewentig kalibrasies is ontwikkel. NIRS ontledings is gedoen met ‘n InfraAlyzer 500 spektrofotometer tussen die golflengtes 1100 en 2500 nm. Naby infrarooi refleksie kalibrasies is ontwikkel vir (i) die basiese chemiese samestelling van volstruisvleis; (ii) die basiese chemiese en minerale samestelling van lamsvleis; (iii) die chemiese samestelling en verteerbaarheid van lupiene en volvet kanola en die bepaling van alkaloïede in lupiene; (iv) die chemiese samestelling en verteerbaarheid van wintergrane en mielies; (v) die chemiese samestelling en verteerbaarheid van graanhooie, graanstrooie, koringstoppels and lusern-gras/hooi mengsels. Die chemiese samestelling van verskillende tipes wintergrane wat in die Wes-Kaap omgewing van Suid-Afrika geproduseer word, sowel as die chemiese samestelling en verteerbaarheid van wintergraanhooi en –strooi wat geproduseer word in ‘n Mediterreënse reënval omgewing, is ook bepaal. Naby infrarooi refleksie spektrofotometrie was suksesvol in die voorspelling van ru-proteïen (RP) en vet in beide dierspesies, sowel as vir die bepaling van as en droë materiaal (DM) in gevriesdroogde lamsvleis. Akkurate kalibrasies is ook ontwikkel vir sekere minerale (K, P, Na, Mg, Fe en Zn). Kalibrasies ontwikkel vir die chemiese samestellings komponente in lupiene is reg deur die bank akkuraat, sowel as die DM, RP en vet kalibrasies vir volvet kanola. Die alkaloïed kalibrasie het goeie potensiaal getoon, alhoewel meer alkaloïedmonsters benodig word vir ‘n akkurate kalibrasie. Wintergraan kalibrasies was akkuraat vir vet, suurbestande vesels (SBV), in vitro organiese materiaal verteerbaarheid (IVOMV), lisien en metionien. Al die chemiese komponent kalibrasies vir mielies, behalwe die een vir as, was akkuraat vir toekomstige bepalings. Chemiese komponent kalibrasies vir koring stoppels en luserngras/ hooi mengsels het akkuraatheid getoon wat gelyk, of effe beter, is as kalibrasies wat in die literatuur opgeteken is. Kalibrasies ontwikkel vir graanhooie en graanstrooie was nie geskik vir voorspellingsdoeleindes nie. Moontlike redes vir die onakkurate kalibrasies is volledig bespreek. Variasie gevind tussen verskillende tipes wintergrane (2-ry gars, 6-ry gars, hawer, koring en korog) het die behoefte beklemtoon vir ontledings van grane geproduseer onder verskillende omgewingstoestande vir gebruik in dierevoeding. Die chemiese samestelling en verteerbaarheid van wintergraanstrooi en –hooi is ook bepaal. Hierdie waardes verskaf ‘n databasis vir berekening by insluiting van hierdie voergewasse in diererantsoene. Hierdie ondersoek het bewys dat NIRS ‘n suksesvolle en vinnige metode is vir die voorspelling van die chemiese samestelling van volstruis- en lamsvleis en plaaslik geproduseerde voergewasse.

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

Thesis (MScAgric)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: The following study is to determine if a creep feed balanced for limiting essential amino acids (EAA) at a certain non structural carbohydrate (NSC) level will elicit greater responses than lambs reared on a commercial creep feed. Lysine, Threonine, Methionine, Isoleucine, Phenylalanine and Leucine were determined as the limiting amino acids for nursing lambs. These amino acids were incorporated into the creep feed treatments CF1 and CF2 representing 157 g CP/kg, 477 g NSC/kg and 179 g CP/kg, 508 g NSC/kg, respectively. A commercial creep feed with no optimisation for EAA is represented as CFC with 139 g CP/kg and 455 g NSC/kg. A negative control (CON) treatment represents lambs receiving no creep feed but with ad libitum access to suckle their dams while feeding on kikuyu pasture. A growth trial was conducted on Merino x Döhne-Merino cross twin lambs averaging a birth weight of 4.42 kg ± 0.11 for 60 days following with a digestibility trial towards the end of the trial. Half of the lamb crop was slaughtered at an average live weight of 23.6 kg ± 0.56. The M. longissimus dorsi was removed on both the left and right half of the carcass between the 2nd - 3rd last thoracic vertebrae and the 4th - 5th lumbar vertebrae. A sample from the rumen wall was taken at the rumino-reticular fold to determine development characteristics. Results indicate that the feed conversion ratio for the CFC lambs were better than CF1 (P = 0.052) but not more than CF2 (P = 0.307). The FCR was 0.88, 1.19 and 1.01 (kilogram feed required to gain 1 kg in bodyweight) for CFC, CF1 and CF2, respectively. Dressing percentage was higher for CF2 than for both CFC (P = 0.012) and CF1 (P = 0.077). Along with BUN data it was concluded that the high CP level of CF2 resulted in the higher fat deposition. The optimised creep feeds had higher nitrogen and energy balances than the commercial CFC, this implicates that the optimised creep feeds were more efficiently utilised. Optimised creep feed treatments had longer papillae than CON (P < 0.0001). Papillae of creep feed 2 was longer than CFC (P = 0.0537). Papillae width decreased as the NSC level increased thus it is surmised that higher NSC levels resulted in longer but thinner papillae. Rumen muscularization was equally developed between all the treatments and was ascribed to the lambs’ access to course roughage. Meat quality in terms of physical and chemical characteristics was found to be in range with that expected for lambs at higher slaughter weights (40 kg). In conclusion, the balancing of the limiting EAA increases the benefits of creep feeding while simultaneously being more efficiently utilised. Intensive sheep production systems may benefit from the feeding of such creep feeds provided it fits economically into their farming system. / AFRIKAANSE OPSOMMING: Die volgende studie is om te bepaal of 'n kruipvoer wat gebalanseerd is vir beperkende essensiële aminosure (EAA) by 'n vasgestelde nie-strukturele koolhidraat (NSK) vlak verbeterde groei sal ontlok teenoor lammers wat grootgemaak word op 'n kommersiële kruipvoer. Lisien, Treonien, Metionien, Isoleusien, Fenylalanien en Leusien is bepaal as die beperkende aminosure vir suipende lammers. Hierdie aminosure is opgeneem in die geoptimiseerde kruipvoer behandelings CF1 en CF2 wat 157 g RP/kg, 477 g NSK/kg en 179 g RP/kg, 508 g NSK/kg onderskeidelik verteenwoordig. 'n Kommersiële kruipvoer met geen optimalisering vir EAA is verteenwoordig as CFC met 139 g RP/kg en 455 g NSK/kg. 'n Negatiewe kontrole (CON) behandeling is verteenwoordig deur lammers wat geen kruipvoer ontvang het nie, maar wat ad libitum toegang tot hul ooi gehad het om te soog terwyl die ooi op ‘n kikoejoeveld wei. 'n Groei proef is uitgevoer met Merino x Döhne-Merino kruis tweelinglammers met ‘n gemiddelde geboorte gewig van 4,42 ± 0,11 kg vir 60 dae en 'n verteerbaarheids proef is na aan die einde van die studie uitgevoer. Helfte van die lam kudde is geslag by die lewende gewig van 23,6 ± 0, 56 kg. Die M. longissimus dorsi was op beide die linker-en regter helfte van die karkas tussen die 2de - 3de laaste torakale werwels en die 4de - 5de lumbale werwels verwyder. 'n Monster van die rumen wand is geneem langs die rumino retikulêre vou sodat die rumen ontwikkeling eienskappe daarmee bepaal kon word. Resultate dui daarop aan dat die voeromsetverhouding (VOV) vir CFC lammers beter was as vir CF1 (P = 0,052), maar nie meer as vir CF2 (P = 0,307) nie. Die VOV was 0,88 , 1,19 en 1,01 (kilogram voer wat nodig is om 1 kg liggaamsmassa aan te sit) vir CFC, CF1 en CF2 onderskeidelik. Uitslag persentasie vir CF2 was hoër as beide CFC (P = 0,012) en CF1 (P = 0,077). Saam met die bloed, urea en stikstofbalans data is daar tot die gevolgtrekking gekom dat die hoë RP inhoud van CF2 gelei het tot ‘n hoër vetneerlegging. Die geoptimaliseerde kruipvoere het ‘n hoër stikstof- en energiebalans gehad teenoor die kommersiële CFC behandeling wat dus impliseer dat die optimale kruipvoere doeltreffender benut was. Die geoptimaliseerde kruipvoer behandelings het langer papillae gehad as CON (P < 0,0001). Papillae lengte van die CF2 behandeling is langer as die van CFC (P = 0,0537). Papillae breedte het dunner geraak soos wat die NSK-vlak gestyg het dus word vermoed dat hoër NSK-vlakke langer maar dunner papillae tot gevolg het. Rumen bespiering is ewe ontwikkeld tussen al die behandelings en word toegeskryf aan die lammers se toegang tot growwe ruvoer. Vleis kwaliteit in terme van fisiese- en chemiese eienskappe was inlyn met wat verwag kan word vir lammers by hoër slaggewigte (40 kg). Ten slotte, die balansering van beperkende aminosure verhoog die voordele van kruipvoeding en word terselfdertyd doeltreffender benut. Intensiewe skaap produksie stelsels kan dus voordeel trek uit die voeding van sodanige kruipvoere mits dit ekonomies pas in die boerdery stelsel.

Thesis (MScAgric)--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: Although kudu (Tragelaphus strepsiceros) and impala (Aepyceros melampus) are found in the same geographical area, there is variation in their diets as kudu are predominantly browsers, feeding on tree and shrub leaves, while impala are known as mixed feeders as they graze and browse. Therefore this poses the question whether the diet would influence their meat quality. The objective of this investigation was to evaluate the physical measurements and chemical composition of M. longissimus dorsi, M. biceps femoris, M. semimembranosus, M. semitendinosus and M. supraspinatus for kudu and impala, two southern African antelope species. The effects of age (adult and sub-adult) and gender (male and female) were also determined. The sensory characteristics of the M. longissimus dorsi muscle for sub-adult kudu and impala were investigated. Correlations between the various physical measurements and chemical composition of the meat were verified. Physical measurements and chemical composition of the M. longissimus dorsi muscle were tested for correlations with the sensory ratings of the meat. Dressing percentage of impala (59.88%) (n=28) was higher than that of kudu (57.60%) (n=35). The main effects (species, gender and age) showed no differences for drip loss and cooking loss. However, muscles differed in terms of cooking loss with impala M. semitendinosus having the highest (38.28%) value and kudu M. longissimus dorsi having the lowest value (30.77%). For impala, the highest Warner–Bratzler shear (WBS) values were measured for M. semimembranosus (5.90 kg/1.27cmø), followed by M. biceps femoris, M. longissimus dorsi, and M. semitendinosus with the lowest WBS values measured for M. supraspinatus (3.61 kg/1.27cmø). All impala muscles had lower L* values and appeared darker in colour than kudu muscles, except for M. supraspinatus. Adult animals also had lower L* values than the sub-adult group. Kudu had significantly higher a* and b* values (more red) than impala. Chroma values were higher for kudu, thus appearing brighter in colour. The respective muscles of kudu and impala investigated differed significantly in terms of physical characteristics. However, gender and age did not have an effect on the physical measurements. Moisture content was higher in kudu meat (76.46%) than in impala meat (75.28%). Muscles differed for both moisture and fat content. The highest fat was found in M. supraspinatus followed by M. biceps femoris, M. semitendinosus, M. semimembranosus and M. longissimus dorsi. Protein content did not differ between species (kudu: 21.66%; impala: 22.26%), gender (male: 21.98%; female: 21.95%) and age groups (adult: 21.74%; sub-adult: 22.18%). Kudu M. longissimus dorsi (1.62%) had lower fat content than impala M. longissimus dorsi (2.22%) and female animals had a higher fat content than male animals. Sub-adults (1.20 ± 0.02%) had higher ash content than adults (1.10 ± 0.03%). The M. supraspinatus had the lowest protein and also the highest fat content, with M. semimembranosus having the lowest fat content but the highest value for protein. Myoglobin content did not differ between species, although females had higher (6.58 ± 0.20 mg/g) myoglobin content than males (5.11 ± 0.25 mg/g). Glycolitic muscles had the lowest myoglobin content with the highest values found in M. supraspinatus, an oxidative muscle. An interaction was noted between species and muscle for myoglobin content. Myoglobin content in impala M. longissimus dorsi was higher than that in kudu M. longissimus dorsi; however for all other muscles the myoglobin content was lower in impala. Gender did not affect mineral content. Potassium levels were highest for kudu while phosphorus was more prevalent in impala meat. Adult and sub-adult groups differed in terms of potassium, calcium and zinc content. Potassium and calcium content were higher for subadult animals while zinc content was higher in adult animals. In impala meat, stearic acid (22.67%) was the major fatty acid, followed by palmitic acid (16.66%). In contrast, oleic acid (24.35%) was the most profuse fatty acid in kudu, followed by linoleic acid (22.95%). The SFA’s as a percentage of the total fatty acids differed between impala (51.12%) and kudu meat (34.87%). Kudu meat had a higher concentration of total PUFA (38.88%) than impala (34.06%) meat. The PUFA: SFA ratio for kudu meat (1.22) was more favourable than that for impala meat (0.73). The ratio of n-6 PUFA’s to n-3 PUFA’s for kudu and impala were determined as 2.22 and 3.76 respectively. From the current findings it is evident that kudu and impala meat have advantageous fatty acid profiles and can be a healthy substitute for other red meats. Kudu meat (72.62 ± 1.86 mg/100g) had higher cholesterol than impala meat (55.35 ± 1.84 mg/100g). It is recommended that further studies be done in order to confirm the cholesterol content of kudu meat. Within species, no gender differences for any of the sensory characteristics tested were noted. The impala meat had a more intense game aroma than the kudu meat, while kudu meat was found to be more juicy than impala meat. It can therefore be concluded that the marketing of game meat should be species-specific as there are distinct flavour and aroma differences between kudu and impala meat. / AFRIKAANSE OPSOMMING: Alhoewel koedoes (Tragelaphus strepsiceros) en rooibokke (Aepyceros melampus) in dieselfde geografiese area voorkom, is daar variasie in hulle diëte. Koedoes is hoofsaaklik blaarvreters, terwyl rooibokke bekend staan as gemengde vreters aangesien hulle grassowel as blaarvreters is. Die vraag ontstaan dus of die verskil in diëet die kwaliteit van hulle vleis sal beϊnvloed. Die doel van hierdie ondersoek was dus om die fisiese metings en chemiese samestelling van die M. longissimus dorsi, M. biceps femoris, M. semimembranosus, M. semitendinosus en M. supraspinatus vir koedoes en rooibokke te bepaal. Die invloed van ouderdom (volwasse en onvolwasse) en geslag (manlik en vroulik) op hierdie eienskappe is ook geëvalueer. Die sensoriese eienskappe van die M. longissimus dorsi van onvolwasse koedoes en rooibokke is ook ondersoek. Korrelasies tussen die fisiese metings en chemiese samestelling van die vleis is ondersoek. Die fisiese metings en chemiese samestelling van die M. longissimus dorsi is getoets vir korrelasies met die resultate van die sintuiglike evaluering van die vleis. Die gemiddelde uitslagpersentasie van rooibokke (59.88%) (n=28) was hoër as die van koedoes (57.60%) (n=35). Daar was geen verskille in drupverlies en kookverlies vir die hoofeffekte (spesie, geslag en ouderdom) nie. Spiere het wel verskil in terme van kookverlies, met die hoogste waarde gemeet vir rooibok M. semitendinosus (38.28%) en die laagste waarde vir koedoe M. longissimus dorsi (30.77%). In rooibokke was die hoogste Warner- Bratzler skeurkrag waardes gemeet vir M. semimembranosus (5.76 kg/1.27cmø), gevolg deur M. biceps femoris, M. longissimus dorsi, en M. semitendinosus met die laagste Warner- Bratzler skeurkrag waardes gemeet vir M. supraspinatus (3.78 kg/1.27cmø). Alle rooibokspiere het laer L* waardes gehad en was donkerder van kleur as koedoespiere, behalwe vir M. supraspinatus. Laer L* waardes is ook verkry vir volwasse diere in vergelyking met onvolwasse diere. Die a* en b* waardes was hoër in koedoe- as in rooibokvleis, m.a.w. koedoevleis het rooier vertoon. Die onderskeie koedoe- en rooibokspiere het betekenisvol verskil in terme van fisiese eienskappe, terwyl geslag en ouderdom geen effek op die fisiese eienskappe gehad het nie. Voginhoud was hoër in koedoe- (75.52%) as in rooibokvleis (74.52%). Verkille tussen spiere is opgemerk vir beide vog- en vetinhoud. M. supraspinatus het die hoogste vetinhoud gehad, gevolg deur M. biceps femoris, M. semitendinosus, M. semimembranosus en M. longissimus dorsi. Geen verskille is opgemerk tussen spesies (koedoe: 21.66%; rooibok: 22.26%), geslagte (manlik: 21.98%; vroulik: 21.95%) en ouderdomme (volwasse: 21.74%; onvolwasse: 22.18%) in terme van proteϊeninhoud nie. Die vetinhoud van koedoe M. longissimus dorsi (1.62%) was laer as dié van rooibok M. longissimus dorsi (2.22%) en die vetinhoud van vroulike diere was hoër as dié van manlike diere. Onvolwasse diere (1.20 ± 0.02%) het ‘n hoër asinhoud as dié van volwasse diere (1.10 ± 0.03%) getoon. In terme van die onderskeie spiere het M. supraspinatus die laagste proteϊen- en die hoogste vetinhoud gehad, terwyl M. semimembranosus die laagste vet- en die hoogste proteϊeninhoud gehad het. Die mioglobieninhoud was nie beϊnvloed deur spesie nie, terwyl vroulike diere ‘n hoër (6.58 ± 0.20 mg/g) mioglobieninhoud as manlike diere (5.11 ± 0.25 mg/g) gehad het. Die M. supraspinatus, ‘n oksidatiewe spier het die hoogste mioglobieninhoud gehad, terwyl glikolitiese spiere die laagste mioglobieninhoud gehad het. ’n Interaksie tussen spesie en spier was opgemerk vir mioglobieninhoud. Rooibok M. longissimus dorsi het ‘n hoër mioglobieninhoud as koedoe M. longissimus dorsi gehad, terwyl die mioglobieninhoud vir al die ander spiere laer was in rooibokke. Mineraalinhoud was nie deur geslag beϊnvloed nie. Kaliumvlakke was hoër in koedoevleis, terwyl fosforvlakke hoër was in rooibokvleis. Kalium- en kalsiuminhoud was hoër in onvolwasse diere terwyl die sinkinhoud hoër was in volwasse diere. Steariensuur (22.67%), gevolg deur palmitiensuur (16.66%) was die mees algemene vetsure in rooibokvleis. In teenstelling hiermee was oleϊensuur (24.35%), gevolg deur linoleϊensuur (22.95%) die mees algemene vetsure in koedoevleis. Die totale versadigde vetsure was laer in koedoevleis (34.87%) in vergelyking met rooibokvleis (51.12%), terwyl die totale polionversadigde vetsure in koedoevleis (38.88%) hoër was as dié van rooibokvleis (34.06%). Die verhouding van n-6 tot n-3 poli-onversadigde vetsure vir koedoe en rooibok was 2.22 en 3.76 onderskeidelik. Hierdie resultate bevestig dat koedoe- en rooibokvleis oor ‘n vetsuurprofiel beskik wat ’n gesonde alternatief bied tot ander rooivleise. Die cholesterolinhoud van koedoevleis (72.62 ± 1.86 mg/100g) was hoër as dié van rooibokvleis (55.35 ± 1.84 mg/100g). Dit word egter aanbeveel dat verdere studies gedoen word om die cholesterolinhoud van koedoevleis te bevestig. Binne spesies was daar geen geslagsverkille vir enige van die sensoriese eienskappe nie. Rooibokvleis het ‘n meer intense wildsvleis aroma as koedoevleis gehad, terwyl koedoevleis meer sappig was as rooibokvleis. Hierdie resultate dui daarop dat die bemarking van wildsvleis spesie-spesifiiek moet wees aangesien daar defnitiewe geur en aroma verskille tussen koedoe- en rooibokvleis is.

Thesis (MscAgric (Animal Sciences))--University of Stellenbosch, 2005. / The aim of this study was to develop a product using alternative red meat species, aquatic and terrestrial mammals, which would be acceptable to the consumer and suitable from a food safety aspect. Many of these alternative species are harvested seasonally. A product which is shelf stable needs to be developed to provide a supply of this meat all year round. The species used in this investigation were the Cape fur seal (Arctocephalus pusillus pusillus), the Grey seal (Halichoerus grypus) from the northern hemisphere, the Minke whale (Balaenoptera acutorostrata), horse, beef, mutton, blesbok (Damaliscus dorcas phillipsi) and springbok (Antidorcas marsupialis). Muscle (m. pectoralis) of Cape fur seal pups has a higher percentage fat (4.2g/100g) than the bulls (2.4g/100g), but similar levels of protein (23.2g/100g). Bull blubber samples have a higher percentage protein (26.6g/100g) than the pups (14.6g/100g), but a lower fat percentage (67.1g/100 g) compared with the pups (77.2g/100g). In the Cape fur seal bull meat, saturated fatty acids (SFA) contribute 33mg/100g, monounsaturated fatty acids (MUFA) 29mg/100 g and polyunsaturated fatty acids (PUFA) 38mg/100g of the total fatty acid content. In pups, the three fractions are 39, 30 and 31 mg/100g for SFA, MUFA and PUFA, respectively. Salami,prepared using exclusively seal meat, or seal meat with beef and pork, was produced in a pilot study, using two commercially available starter cultures. The pH values of all three batches started off at ca. 5.6, and dropped to 4.3. Water activity readings started off at 0.96 and dropped to 0.91 after 21 days. Salami produced from the meat of the Grey (Havert) seal and Minke whale, using three starter cultures, had recorded pH values (in both species), which started off between 5.68 and 5.92, and dropped to between 4.5 and 4.8 over the 21 days. Water activity showed an initial value of 0.96, which dropped to 0.90 after 21 days. The final force (N/cm2) that was needed to compress the salami samples was double that of the initial force required for the same species and starter culture combination. The raw seal meat contained 349.6 (mg/100 g sample) SFA, 271.6 (mg/100g sample) MUFA and 175.8 (mg/100g sample) PUFA, whilst the raw whale meat contained 312.3, 251.9 and 179.6 (mg/100g sample) SFA, MUFA and PUFA respectively. Fifteen batches of salami were made from horse, beef, mutton, blesbok and springbok, respectively, and starter cultures of Lactobacillus curvatus DF 38 (batch I), active bacteriocin producing Lactobacillus plantarum 423 (batch II) and then a mutant variation of Lactobacillus plantarum 423m, which did not produce the bacteriocin (batch III). Batch I had a higher final pH value (4.66), after 23 days, whereas the values for batches II and III were similar (4.42 and 4.46 respectively). On day 23 the water activity value was 0.90 for all starter cultures. Horse salami, in batch I, was the leanest in terms of fat content (34.34g/100g salami), with mutton salami having the highest fat content (37.52g/100g salami). Blesbok salami had the highest fat content in batch II (42.77g/100g meat), with beef the leanest (35.71g/100g meat). Salami made from horse and springbok proved to be the most desirable in terms of chemical composition, especially fatty acid profiles, with regard to P: S and n-6: n-3 ratios. Similar growth patterns in colony forming units (cfu) were recorded for L. plantarum 423, L. plantarum 423m and L. curvatus DF38 in MRS broth (Merck) at 30oC, although batch I reached asymptotic growth earlier. The percentage of L. plantarum 423 compared with the total population of microflora in mutton salami remained almost the same (80-95% variety) during the entire fermentation and maturation process. In horse salami, L. plantarum 423 was present at relatively low cell numbers (55-50% on day 1 and before smoking), but increased to 70% after smoking and stabilized to 70-80% for the remaining fermentation period. In beef salami, cell numbers in batch II decreased slightly during the first five days (from 95 to 70%), followed by an increase to 90%. In springbok salami, cell numbers in batch II remained fairly stable at 80-90%. In blesbok salami, batch II slowly decreased during the first three days, from 88% to 70%, then increased to 92% after 12 days and stabilized for the rest of the fermentation period. Similar results were recorded for batch I. Analytical sensory evaluation concluded that the salami prepared using starter culture I resulted in end products with lower sensory qualities. Salami prepared using blesbok and mutton also resulted in end products with lower sensory qualities and was perceived as significantly lower in salami flavour (P≤0.05) and higher in venison-like and mutton-like flavour respectively. The blesbok samples were rated significantly higher (P≤0.05) in sour meat aroma, sour meat flavour and venison-like flavour than the rest of the samples. The blesbok salami was rated significantly lowest for colour compared with the rest of the samples. The tastes of the springbok and horse salami were significantly (P≤0.05) more acceptable than those of the beef and blesbok salami.