Abstract
M.Tech. (Food Technology)
Mycotoxins are toxic fungal metabolites and their indispensable nature in agriculture generates serious problems associated with food and farming systems for both human and animals worldwide. In this regard, the dairy farming sector is largely affected, with feeds routinely being contaminated posing a risk factor to productivity and animal health. In addition to this, the potential for carry-over of mycotoxins from animals to humans via consumption of contaminated animal by-products remains apparent thus making mycotoxin surveillance and monitoring a necessity in the bid to preserve public health. Such studies are very limited in South Africa. The overall aims of this study were therefore, to establish an understanding of Gauteng dairy farmer perception on mycotoxins and subsequently determine the degree with which the dairy cattle feeds are contaminated by these mycotoxins.
A socio-demographic survey was undertaken in the Gauteng Province of South Africa, where 13 randomly selected dairy farms from various locations in the region participated by completing self-administered open- and closed-ended questionnaires. Additionally, similar farmers voluntarily donated representative samples of feeds and feed components for their animals. A total of 40 dairy feeds from different classes comprising maize grits, commercial dairy meals, silages, grasses, total mixed rations, brewer’s spent grains, molasses, bran and oilcake were therefore collected and analyzed for multi-mycotoxin contamination. Estimations of levels of aflatoxins (AFB1, AFB2, AFG1 and AFG2), fumonisin B1 (FB1), ochratoxin A (OTA), citrinin (CIT), zearalenone (ZEN), α-zearalenol (α-ZEL), β-zearalenol (β-ZEL), deoxynivalenol (DON), 3- and 15-acetyl-deoxynivealenol (ADONs), HT-2 toxin (HT-2) and beauvericin (BEA) were established using an ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UHPLC- QTOF–MS/MS). Calibration curves for all analytes showed good linearity (R2 > 0.998). The overall limits of detection (LODs) and quantification (LOQs) were in the range of 0.02- 3.46 ppb and 0.06- 11.52 ppb, respectively.
On perception studies, data obtained indicated that all farmers had a general knowledge on mycotoxins and their associated risks, however, it was also revealed that there is generally among farmers, limited understanding of mycotoxin legislation and modern forms of mitigation strategies they may have access to as farmers. With regards to mycotoxin contamination in this study, data...