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dc.contributor.advisorButler, H. J. B.
dc.contributor.authorWiid, Emmarentia Elsabe
dc.date.accessioned2018-02-21T10:23:53Z
dc.date.available2018-02-21T10:23:53Z
dc.date.issued2017-03
dc.identifier.urihttp://hdl.handle.net/11660/7850
dc.description.abstractEnglish: Modern confinements imposed on animals limit their access to natural resources required for optimal nutrition. This lack of resources may lead to nutrient deficiencies and one of the hypotheses for the deliberate consumption of soil is to supplement mineral deficiencies. Counteraction of acidosis, detoxification, buffering of unpalatable plant compounds as well as the use of soil as anti-diarrhoeal agent are other suggested motivations for geophagy. By means of direct observation as well as camera traps, the behaviour of geophagy amongst dairy cows in a confined feedlot system was documented. In addition, soil analysis was done to determine the geochemistry of ingested as well as excreted soil. Geophagy amongst cows at Amperplaas constituted less than 2% of daily activity. The non-lactating individuals invested less time in this behaviour than lactating individuals and the frequency as well as time spent on this behaviour decreased as the lactation phases progressed. Recorded geophagy occurrences were most during winter and thereafter spring and peak soil ingestion occurred during mid-day. At Amperplaas, all but one of the mineral licks were situated on the undisturbed elevated areas underneath the fence wire or around the wooden and iron poles. The average size of a typical mineral lick was about 40 cm by 15 cm with a depth of 10 cm. The soil collected from the mineral licks was alkaline and classified as sandy clay loam. Quartz, Plagioclase and K-Feldspar were identified in all samples while Ilmenite was quantifiable in all but one of the control sites. Silica concentrations were supportive of quartz dominance in the soil collected from mineral licks as well as soil from the stomachs and faecal matter. The most recent mineral lick contained the lowest silica, arsenic, copper, lead, scandium, and zirconium content. But this site had elevated calcium, iron, potassium, magnesium, sodium and phosphorus as well as bromine, nickel, strontium and zinc levels. When offered soil combined with different minerals, the preference of most cows was sodium chloride mixture and thereafter calcium-phosphorus. When comparing the estimated amount of soil ingested per second with the excreted amount of soil, it appears that the daily excretion rate of soil is almost equal to the ingestion rate, therefore not posing any threat for sand impaction. Milk collected at Amperplaas had low levels of calcium as well as potassium and therefore, soil is possibly ingested to supplement this deficiency. Results of this study confirm the ability of some animals to detect deficiencies in the body and to attempt to correct these deficiencies from available resources. Results also support the theories that this nutritional wisdom is partly from cultural transmission as well as innate behaviour.en_ZA
dc.description.abstractAfrikaans: Diere in aanhouding word van toegang tot natuurlike hulpbronne wat noodsaaklik is vir optimale voeding ontneem. Hierdie gebrek aan hulpbronne kan lei tot verskeie voedingstekorte en een van die hipoteses vir die doelbewuste inname van grond is om mineraaltekorte aan te vul. Die teenwerk van asidose (suurvergifting), ontgifting, die buffer van onsmaaklik plant verbindings, asook die gebruik van grond as anti-diarreale middel is ander voorgestelde motiverings vir geofagie. Deur middel van direkte waarnemings en kamera lokvalle is geofagie by melkkoeie in 'n voerkraal stelsel gedokumenteer. Addisionele grondontledings is uitgevoer om die geochemie van gevrete asook uitgeskeide grond te bepaal. Koeie by Amperplaas spandeer minder as 2% van daaglikse aktiwiteite aan grondvreet. Nie-lakterende individue spandeer minder tyd aan hierdie gedrag as lakterende individue en die frekwensie asook tyd spandeer aan hierdie gedrag verminder soos die laktasie fases vorder. Aangetekende voorvalle van geofagie was die meeste tydens die winter en daarna die lente en grondvreet het ‘n hoogtepunt bereik gedurende die middel van die dag. Al die mineraal lekke by Amperplaas, met die uitsondering van een, was op die ongestoorde, verhewe areas onder die kampdrade of rondom die hout- en ysterpale geleë. 'n Tipiese mineraal lek het afmetings van ongeveer 40 by 15 cm met ‘n diepte van 10 cm gehad. Grond wat by die mineraal lekke versamel was is geklassifiseer as alkaliese sanderige leem klei. Kwarts, plagioklaas en K-Veldspaat is in alle monsters geïdentifiseer terwyl ilmeniet slegs by een kontrole gebied nie gevind is nie. Hoë silika konsentrasies was ondersteunend van die kwarts oorheersing in die versamelde grond van die mineraal lekke asook van grond wat uit die pense en mis verwyder is. Die mees onlangse gevestigde mineraal lek het die laagste silika, arseen, koper, lood, skandium en sirkonium inhoud gehad. Hierdie lek het ook verhoogde vlakke van kalsium, yster, kalium, magnesium, natrium en fosfor asook broom, nikkel, strontium en sink gehad. Grond, gemeng met verskeie minerale, is vir die koeie aangebied en die voorkeur van meeste koeie was die natrium kloried mengsel met kalsium-fosfor mengsel as tweede keuse. Wanneer die geskatte hoeveelheid grond wat ingeneem is met die uitgeskeide hoeveelhede vergelyk word, blyk dit dat die daaglikse uitskeidingstempo van grond byna gelyk is aan die tempo van inname. Daar dus nie ‘n risiko vir sandverstopping by die koeie van Amperplaas nie. Melk wat versamel is by Amperplaas het lae vlakke van kalsium sowel as kalium getoon en grond word heel waarskynlik ingeneem om verligting vir hierdie tekort teweeg te bring. Resultate van hierdie studie bevestig dat diere oor die vermoë beskik om tekorte in die liggaam agter te kom en dus te poog om hierdie tekorte vanuit beskikbare hulpbronne reg te stel. Resultate ondersteun vervolgens die teorieë dat hierdie voedingswysheid deels aan kulturele oordrag en deels aan aangebore gedrag toegeskryf kan word.en_ZA
dc.description.sponsorshipInkaba yeAfricaen_ZA
dc.language.isoenen_ZA
dc.publisherUniversity of the Free Stateen_ZA
dc.subjectDairy cowsen_ZA
dc.subjectFeedlot systemen_ZA
dc.subjectGeophagyen_ZA
dc.subjectMineral deficiencyen_ZA
dc.subjectMacro and micro elementsen_ZA
dc.subjectMineral supplementen_ZA
dc.subjectFree-choice mineral selectionen_ZA
dc.subjectDairy cattle -- Feeding and feedsen_ZA
dc.subjectFeedlotsen_ZA
dc.subjectDissertation (M.Sc. (Zoology and Entomology))--University of the Free State, 2017en_ZA
dc.titleAspects of geophagia amongst dairy cattle in a feedlot systemen_ZA
dc.typeDissertationen_ZA
dc.rights.holderUniversity of the Free Stateen_ZA


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