Full Text Available
Note: Clicking the button above will open the full text document at the original institutional repository in a new window.
Mycotoxin contamination in commonly used raw feed materials within South African sheep feedlots and the effect of mycotoxin deactivators on production parameters and profitability
Thesis (MScAgric)--Stellenbosch University, 2024.
Saved in:
| Main Author: | |
|---|---|
| Other Authors: | |
| Format: | Thesis |
| Published: |
Stellenbosch : Stellenbosch University
2025
|
| Subjects: | |
| Tags: |
No Tags, Be the first to tag this record!
|
| _version_ | 1867613998668578816 |
|---|---|
| access_status_str | Open Access |
| author | Van Wyk, Luhan Hamman |
| author2 | Van Zyl, Johan Hendrik Combrink
|
| author_browse | Van Wyk, Luhan Hamman Van Zyl, Johan Hendrik Combrink |
| author_facet | Van Zyl, Johan Hendrik Combrink
Van Wyk, Luhan Hamman |
| author_sort | Van Wyk, Luhan Hamman |
| collection | Thesis |
| dc_rights_str_mv | Stellenbosch University |
| description | Thesis (MScAgric)--Stellenbosch University, 2024. |
| format | Thesis |
| id | oai:scholar.sun.ac.za:10019.1/131962 |
| institution | Stellenbosch University (South Africa) |
| last_indexed | 2026-06-10T12:45:01.662Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository |
| publishDate | 2025 |
| publishDateRange | 2025 |
| publishDateSort | 2025 |
| publisher | Stellenbosch : Stellenbosch University |
| publisherStr | Stellenbosch : Stellenbosch University |
| record_format | dspace |
| source_str | SUNScholar — Stellenbosch University Repository |
| spelling | oai:scholar.sun.ac.za:10019.1/131962 Mycotoxin contamination in commonly used raw feed materials within South African sheep feedlots and the effect of mycotoxin deactivators on production parameters and profitability Van Wyk, Luhan Hamman Van Zyl, Johan Hendrik Combrink Steyn, L. Stellenbosch University. Faculty of AgriSciences. Dept. of Animal Science. Sheep -- Breeding Microfungi Livestock -- Feeding and feeds -- Contamination Mycotoxicoses in animals Mycotoxins Feedlots -- South Africa Raw feed materials UCTD Thesis (MScAgric)--Stellenbosch University, 2024. ENGLISH ABSTRACT: Microfungi (moulds) produce toxic compounds as a means of gaining a competitive advantage when they compete for the substrate from which they live. Although beneficial for the survival of these microfungi, these toxic compounds have a profound impact on the health status of organisms which encounter them. The class of toxic compounds produced by microfungi that are detrimental to the health of vertebrates have come to be known as mycotoxins (MTs). The health implications brought about by MTs are known as mycotoxicosis, which involve different symptoms depending on the structure and concentration of MT exposure. Microfungi that produce MTs infect a wide array of substrates over a vast number of regions all over the world. Due to the fact that these microfungi are in a sense omnipresent, the toxic effects of MTs are seen in a wide range of vertebrates. Livestock animals such as pigs, chickens, cows and sheep which are vertebrates, fall victim to mycotoxicosis which impede these animals’ abilities to produce optimally and thereby reduce the amount of valuable food commodities that were destined for the table of the South African consumer. Sheep meat is one of these commodities that play an integral role in the food sector of South Africa. The hardiness of sheep and the sensory attribute of its meat appeals to sheep producers in South Africa who aim to maximize profit from their sheep production systems. Sheep feedlots are a means of increasing monetary output of sheep production systems. However, feedlots require substantial monetary inputs, which significantly impact the profit of these systems. Profit gain is the main drive behind any production system. Therefore, sheep producers always strive to increase their profit by as large a margin as possible. When factors arise which could impede profit gains, they should be investigated and addressed. One such factor which could impede profit gains is the effect of mycotoxicosis on sheep in feedlots. With all this considered, this thesis as a whole addressed the question on what the MT contamination of commonly used raw feed materials (RFM) in South African sheep are. Comparisons were drawn among various RFMs which included: maize, gluten meal, wheat bran, hominy chop and lucerne hay. Among these, maize and its by-products which include gluten 20 and hominy chop showed elevated risk levels with regards to MT tolerance in sheep. This comparison of RFMs commonly used in South African sheep feedlots, highlights that the fact that sheep feedlot producers in South Africa should approach the inclusion of maize, gluten 20 and hominy chop with caution. In a second study, the authors found that the use of commercially available MT deactivators did not lead to increases in production parameters, carcass characteristics or profit in South African sheep feedlots, although studies by other authors do show increases for these three variables in monogastric and dairy production systems. Although no increases in profit were found, no decreases were shown either, which implies that these MT deactivators could still be added to the feeds without decreasing profit. This, in turn, means that MT deactivators can act as an insurance policy to safeguard animals against an MT flare-up caused by a slip-up in the maintenance of good agricultural and post-harvest practices. AFRIKAANSE OPSOMMING: Muwwe produseer toksiese middels as ʼn strategie om ʼn kompeterende voordeel te verower wanneer hulle veg vir toegang tot groeimedium. Alhoewel hierdie toksiese middels as ʼn voordeel dien vir die muf wat dit produseer, kan dit tot groot skade lei in organismes wat in aanraking kom met hierdie middels. Die klas van toksiese middels wat deur muwwe produseer word en spesifiek ʼn invloed het op gewerweldes, staan bekend as mikotoksiene (MTe). Mikotoksikose omskryf die toestand van gesondheidsimplikasies veroorsaak deur hierdie sogenaamde MTe. Die tipe en erns van mikotoksikose hang af van die molekulêre struktuur en konsentrasie van die MT betrokke. Muwwe het die vermoë om ‘n verskeidenheid groeimediums te besmet oor ʼn wye reeks streke van regoor die wêreld. As gevolg van die feit dat muwwe tot ʼn mate alomteenwoordig is, is die toksiese uitwerking van MTe in ʼn wye verskeidenheid van gewerwelde diere sigbaar. Vee, onderandere varke, hoenders, koeie en skape is voorbeelde van gewerweldes wat slagoffers kan wees van mikotoksikose en sodoende word die diere se vermoë om optimaal te produseer belemmer. Hierdeur word noodsaaklike voedsel kommoditeite wat die Suid-Afrikaanse verbruiker se bord moet bereik, verminder. Skaapvleis is een van die hierdie voedsel kommoditeite wat ʼn belangrike rol vertolk in die voedsel sektor van Suid-Afrika. Die gehardheid van skape asook die gesogte sensoriese eienskappe van skaapvleis maak dat die skaapvleis produsente in Suid-Afrika winste kan nastreef deur die produsering van hierdie diere. Voerkrale maak groot opspraak onder skaap produsente weens die merkwaardige toename in uitset wat dit kan oplewer. Hierdie merkwaardige toename in uitset is wel onderhewig aan merkwaardige toenames in insette wat ʼn invloed het op die wins wat voerkrale oplewer. Die najaag van wins is die hoof dryfkrag agter enige produksie sisteem. Skaap produsente is gevolglik voortdurend aan die streef om hul winsmarge so hoog as moontlik te kry. Wanneer daar egter faktore na vore kom wat winsmarge negatief kan beïnvloed, moet dit ondersoek en aangespreek word. Soos vroeër genoem is een van die faktore wat winsmarge kan beïnvloed, die invloed van mikotoksikose in skape wat in voerkrale geproduseer word. Met betrekking tot als sover genoem, is hierdie tesis opgestel in ʼn poging om die invloed van MT besmetting van alledaags gebruikte rou voermateriale (RVM) in skaap voerkrale, asook die invloed van MT deaktiveerders op die produksie en winsmarge van skaap voerkrale in Suid-Afrika, te ondersoek. Die eerste deel van die ondersoek het ʼn vergelyking getref tussen die MT belading van ʼn verskeidenheid RVMe, wat onder andere, mielies, glutenmeel, koring semels, fynmielie semels, en lusern ingesluit het. Van hierdie RVMe genoem was mielies, glutenmeel, en fynmielie semels geklassifiseer as hoogs riskant met betrekking tot die toleransie vlakke van skape. Dus moet produsente van skape in voerkrale die insluiting van mielies, glutenmeel en fyn mieliesemels versigtig benader wanneer hulle skaap rantsoene aan mekaar sit. In die tweede deel van die ondersoek het die skrywers gevind dat die gebruik van kommersiële MT deaktiveerders nie ʼn verhoogde winsmarge tot gevolg het nie. Daar is wel studies wat toon dat MT deaktiveerders tot ʼn verhoogde winsmarge in enkelmaag- en suiwel produksie-stelsels lei. Alhoewel daar gevind is dat MT deaktiveerders geen styging veroorsaak het op die winsmarge van skaap voerkrale nie, kan daar ook gesê word dat dit geen afname in die wins van skaap voerkrale tot gevolg het nie. Dus kan hierdie kommersiële MT deaktiveerders bygevoeg word tot die voer van skape en sodoende as ‘n versekerings-beleid dien vir wanneer die MT besmetting moontlik onvoorspelbaar kan toeneem as daar nie by goeie boerdery en na-oes praktyke gehou word nie. Masters 2025-05-02T09:33:35Z 2025-05-02T09:33:35Z 2024-12 Thesis https://scholar.sun.ac.za/handle/10019.1/131962 Stellenbosch University xi, 79 pages : illustrations, maps application/pdf Stellenbosch : Stellenbosch University |
| spellingShingle | Sheep -- Breeding Microfungi Livestock -- Feeding and feeds -- Contamination Mycotoxicoses in animals Mycotoxins Feedlots -- South Africa Raw feed materials UCTD Van Wyk, Luhan Hamman Mycotoxin contamination in commonly used raw feed materials within South African sheep feedlots and the effect of mycotoxin deactivators on production parameters and profitability |
| title | Mycotoxin contamination in commonly used raw feed materials within South African sheep feedlots and the effect of mycotoxin deactivators on production parameters and profitability |
| title_full | Mycotoxin contamination in commonly used raw feed materials within South African sheep feedlots and the effect of mycotoxin deactivators on production parameters and profitability |
| title_fullStr | Mycotoxin contamination in commonly used raw feed materials within South African sheep feedlots and the effect of mycotoxin deactivators on production parameters and profitability |
| title_full_unstemmed | Mycotoxin contamination in commonly used raw feed materials within South African sheep feedlots and the effect of mycotoxin deactivators on production parameters and profitability |
| title_short | Mycotoxin contamination in commonly used raw feed materials within South African sheep feedlots and the effect of mycotoxin deactivators on production parameters and profitability |
| title_sort | mycotoxin contamination in commonly used raw feed materials within south african sheep feedlots and the effect of mycotoxin deactivators on production parameters and profitability |
| topic | Sheep -- Breeding Microfungi Livestock -- Feeding and feeds -- Contamination Mycotoxicoses in animals Mycotoxins Feedlots -- South Africa Raw feed materials UCTD |
| url | https://scholar.sun.ac.za/handle/10019.1/131962 |
| work_keys_str_mv | AT vanwykluhanhamman mycotoxincontaminationincommonlyusedrawfeedmaterialswithinsouthafricansheepfeedlotsandtheeffectofmycotoxindeactivatorsonproductionparametersandprofitability |