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Meat quality parameters of the impala (Aepyceros melampus)Kritzinger, Brian 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: The purpose of this study was to evaluate the effects of age, sex, region and cropping
methodology on the meat quality of impala. Forty impala were cropped during separate
day and night operations at the Mara Agricultural Development Centre. Carcass pH45
(measured in M. longissimus dorsi 45 minutes post mortem) was higher in night cropped
animals (6.67 ± 0.111; P<0.05) compared to the day cropped animals (6.55 ± 0.236).
The ultimate carcass pH (pHu) of animals cropped at night was lower (5.39 ± 0.081;
P<0.05) compared to those cropped in the day (5.45 ± 0.108). Non-linear regression
analysis showed that the rate of pH decline of the night cropped animals was slower
than that of the day cropped animals (P<0.05). The cooling rate of the M. longissimus
dorsi was twice as fast in the night cropped group (P<0.05). Shear force values and drip
losses of the night cropped animals were both lower (19.11 ± 5.675 g/mm2 and 2.93 ±
1.597% respectively; PO.OS) compared to those of day cropped animals (23.42 ± 8.128
g/mm2 and 4.15 ± 2.339%). The results indicate that nighttime cropping has a beneficial
effect on certain meat quality parameters compared to daytime cropping.
A second group of impala was sampled at the Musina Experimental Farm in the
Limpopo Province of South Africa. Live weights of the Mara animals (50.23 ± 9.32 kg)
were higher (P<0.05) than the Musina animals (44.25 ± 10.81 kg). Impala sampled at
Mara had significantly higher dressing percentages than those at Musina (P<0.05).
Impala ewes from both regions had a higher lipid content (P<0.05), but the sex of the
animal had no effect on the remaining chemical parameters. The crude protein content
of impala at Musina (24.88 ± 1.044%) was higher (P<0.05) than the Mara animals (23.80
± 0.840%).
Regional differences (P<0.05) were found in the amounts of phosphorous and calcium in
the meat. Female animals at Mara showed higher proportions (P<0.05) of saturated
(SFA), and mono-unsaturated fatty acids than the male animals. Males from both
regions showed higher proportions (P<0.05) of poly-unsaturated fatty acids. Myristic,
palmitic and stearic acid formed the greatest proportion of the SFA component for males
and females from both regions. Samples of the M. semi-membranosus (SM), M. deltoideus (D), M. longissimus dorsi et
laborum (LO), and M. psoas major (PS) were analysed for citrate synthase (CS) and
phosphofructo-kinase activities. MHC distribution varied significantly between 0, SM and
LD (P<O.05). D expressed more MHC I, and less MHC lIa than the other three muscle
groups. Positive correlations were found between age and MHC I in 0 (r=O.93; P<O.05)
and CS and weight of the animal in D (r=O.76; P<O.05). The enzyme activities and MHC
distribution indicate that energy in the impala is produced to a large extent via oxidative
pathways. / AFRIKAANSE OPSOMMING: Die doel van hierdie studie was om die invloed van ouderdom, geslag, area, en
uitdunmetodes op die vleiskwalitiet van rooibokke te evalueer. Veertig rooibokke is
gedurende afsonderlike dag en nag uitdunningsoperasies by die Mara Landboukundige
Ontwikkelings Sentrum geoes. Karkas pH45 (gemeet in die M. longissimus dorsi 45
minute post mortem) was hoër (P<0.05) in nag-geoesde diere (6.67 ± 0.11) in
vergelyking met die dag-geoesde diere (6.55 ± 0.23). Die finale pH (pHu) van diere wat
in die nag geoes is (5.39 ± 0.08) was laer (P<0.05) in vergelyking met die wat in die dag
geoes is (5.45 ± 0.11). Nie-lineêre regressie analise toon dat die tempo van pH-daling
van die nag-geoesde diere merkbaar stadiger was as die dag-geoesde diere (P<0.05).
Die afkoelings tempo van die M. longissimus dorsi et lumborum was twee keer vinniger
in die nag geoesde groep (P<0.05). Die gemiddelde skeurkragwaarde en drupverlies
was beide laer (P<0.05) vir nag geoesde diere (respektiewelik 19.11 ± 5.67 g/mm2 en
2.93 ± 1.59%) in vergelyking met diere wat in die dag geoes is (23.42 ± 8.12 g/mm2 en
4.15 ± 2.33%). Die resultate toon dat nag-uitdunning 'n voordelige effek op vleiskwaliteit
gehad het, in vergelyking met dag-uitdunning.
'n Tweede groep van rooibokke is gemonster by die Musina Eksperimentele plaas in die
Limpopo Provinsie in Suid-Afrika. Die gewigte van die Mara diere (50.23 ± 9.32 kg) was
hoër (P<0.05) as die van die Musina diere (44.25 ± 10.81 kg). Die Mara groep het hoër
uitslag persentasies (P<0.05) gehad. Vroulike diere in beide areas het 'n hoër vet
inhoud (P>O.05) gehad. Die ru-proteien inhoud van die Musina diere (24.88 ± 1.04%)
was hoër (P<0.05) as die van die Mara diere (23.80 ± 0.84%).
Area verskille (P<0.05) is gevind in die fosfaat en kalsium inhoud in die vleis. Vroulike
diere by Mara het 'n hoër proporsie (P<0.05) van versadigde en mono-onversadige
vetsure in die weefsel as manlike diere gehad. Manlike diere van beide areas het 'n hoër
proporsie (P<0.05) van poli-onversadige vetsure (P<0.05) as die vroulike diere getoon.
Miristien, palmitien en stearien suur was kwantitatief die belangrikste vetsure in manlike
en vroulike diere van beide areas. Monsters van die M. semi-membranosus (SM), M. deltoideus (D), M. longissimus dorsi
et laborum (LO), en M. psoas major (PS), van die rooibokkarkasse is ontleed vir
sitraatsintase (SS) en fosfofruktokinase aktiwiteite (FFK). MSK verspreiding het
merkbaar varieer tussen 0, SM en LO (P<O.05). 0 toon meer MSK I en minder MSKlia
as die ander drie spiergroepe (P<O.05). Postiewe korrelasies is bevind tussen
ouderdom en MSK I in 0 (r=O.93; P<O.05), asook tussen SS en die gewig van die dier in
o (r=O.76; P<O.05). Die ensiemaktiwiteite en MSK verspreiding toon dat energie in die
rooibok tot 'n groot mate deur die oksidatiewe paaie geproduseer word.
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Wildlife utilisation by local people in Papua : a case study from Bupul Nature Reserve and Danau Bian Game Reserve, Papua, Indonesia /Ariantiningsih, Fransisca. January 2005 (has links) (PDF)
Thesis (M.Anim.Sc) - University of Queensland, 2005. / Includes bibliography.
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Consumptive wildlife utilization as a land-use form in NamibiaErb, Karl Peter 03 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: This study summarizes data for the consumptive wildlife industry in Namibia, both in
terms of resource availability and current utilization and monetary value. Based on
these data a spreadsheet-based cash-flow model is developed to simulate scenarios
and to explore what constitutes the critical parameter. Based on this data synthesis
and modelling, recommendations are made and conclusions drawn.
Chapter one gives an overview of Namibia's economy, with special reference to the
livestock and wildlife industry. The fact that the commercial livestock herd has been
shrinking over the years is pointed out, as well as the stable output achieved through
better management practices. The literature research has shown that wildlife
ranching could be a viable alternative to livestock farming as practised in southern
Africa, especially in the more arid areas with higher rainfall variability.
Chapter two outlines the resource availability, based on the distribution and densities
of the more common species. The occurrence of the rarer species is touched on.
The point is made that it is very difficult to accurately count wildlife over large areas
and that, as elsewhere, Namibia's wildlife at a regional scale is underestimated.
Chapter three documents the consumptive use of wildlife. Trophy hunting, the most
important segment in terms of national income, is discussed together with the live
sale of game, live export of game, venison production and night culling. A
comparison is made between the economic outputs of the wildlife industry versus
that of the commercial cattle industry.
Chapter four covers financial modelling and the economics of the wildlife industry in
Namibia. A spread-sheet based deterministic model is developed to explore the
cash-flow implications of various game ranching options, such as using different
species mixes, owning land of different carrying capacities and offering different
services.
Chapter five addresses policy and legislative issues in relation to the wildlife industry.
Topics such as property rights and exclusive utilization rights, industry representation
and the forming of smart partnerships with primary resource users are covered.
Broad recommendations are made to the Ministry of Environment and Tourism.
Chapter six is used for a concluding synthesis of the previous four chapters. / AFRIKAANSE OPSOMMING: Hierdie studie som die konsumptiewe wildlewe industrie in Namibie op in terme van
van beide beskikbaarheid, huidige verbruik en monetere waarde van hierdie
hulpbron. Gebaseer op hierdie data is 'n kontantvloei model opgestel om
vooruitskouings te simuleer, met betrekking op aanbevelings en gevolgtrekkings.
Hoofstuk een gee 'n oorsig van die Namibiese ekonomie met spesiale verwysing na
die vee- en wildboerdery. Daar word uitgewys dat die gesamentlike kommersiele
veekudde oor die afgelope aantal jare kleiner geword het, terwyl die opbrengs stabiel
gebly het deurdat better bestuurspraktyke toegepas is. Die literatuurstudie het
gewys dat in suider-Afrika, wildlewe-boerdery 'n lewensvatbare alternatief kan wees
vir veeboerdery, veral in die droër streke wat 'n hoër reenval speling toon.
Gebaseer op die verspreiding en digtheid van die meer algemene wild, gee hoofstuk
drie 'n oorsig van die beskikbaarheid van hierdie hulpbronne. Trofeejag, wat die
belangrikste inkomstesektor is, word bespreek, sowel as die lewende verkoop,
uitvoer en nagoes (skiet van diere gedurende die nag vir vleisproduksie) van wild,
asook die wildvleis produksie. Met betrekking tot die ekonomiese uitsette, word 'n
vergelyking gemaak tussen die wildlewe en kommersiele veeboerdery industrie.
Hoofstuk vier dek die finansiele modelering en ekonomiese aspekte van die wildlewe
industrie in Namibie. 'n Rekenaar "spreadsheet" -gebaseerde, deterministiese model
is ontwikkel om die kontantvloei van verskeie opsies van wildlewe boerdery te
verken. Voorbeelde sluit in die gebruik van verskillende spesie samestellings, die
besit van grond met verskillende drakrag vermoëns, asook die aanbiedinge van
verskeie dienste.
Hoofstuk vyf bespreek die beleid en wetgewing met betrekking tot die wildlewe
industrie. Onderwerpe soos eiendomsreg en eksklusiewe benuttingsregte, industrie
verteenwoordiging en die stigting van "smart" vennootskappe met primere hulpbron
verbruikers, word aangespreek. Aanbevelings word aan die Ministerie van
Omgewing en Toerisme gemaak.
Hoofstuk ses behels 'n sintese van die voorafgaande vier hoofstukke.
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