Aline Moreira Borowsky

The diet of dairy calves can be contaminated with mycotoxins, posing a potential risk to animal health. This case study report aimed to make the first assessment of the presence of multiple mycotoxins in concentrates fed to dairy calves in Brazil. A total of 19 concentrate samples intended for dairy calves were analyzed using liquid chromatography coupled with mass spectrometry. Aflatoxins, deoxynivalenol, and T-2 toxin were not detected in any samples, whereas fumonisins B₁ (FB₁) and B₂ (FB₂) were present in 100% of the samples, with mean concentrations of 2750.1 μg/kg and 834.9 μg/kg, respectively. Zearalenone (ZEN) was detected in 36.8% of samples, with a mean concentration of 929.9 μg/kg. Significant correlations were observed between FB₁ and FB₂ (ρ = 0.978; p < 0.001) and between FB₂ and ZEN (ρ = 0.735; p = 0.05). While the physical form of the concentrate did not influence (p > 0.05) mycotoxin concentrations, a trend was observed for FB₁ (ρ = −0.417; p = 0.07) and FB2 (ρ = −0.395; p = 0.09). These findings highlight the frequent occurrence of Fusarium mycotoxins, likely due to pre-harvest contamination, emphasizing the potential risk of additive or synergistic effects in dairy calves.

Contamination by multi-mycotoxins in cattle feed can lead to increased susceptibility to diseases and loss of performance. The present study aimed to investigate the occurrence of multiple mycotoxins present in the diet of beef cattle feedlots in Brazil. Chromatographic analyses were performed on 152 TMR samples from seven states, representing the diet provided to 1,246,522 animals. Contamination by mycotoxins was found in 100% of the TMR samples analyzed, with the most frequent being fumonisins, present in 100% of the samples, followed by zearalenone, which contaminated 79.6% of the samples, and subsequently by aflatoxins, deoxynivalenol, and T-2, while HT-2 was not detected in any of the samples. Furthermore, 2.6% of samples showed co-occurrence of five different types of mycotoxins, 23.7% presented four mycotoxins, 41.4% three mycotoxins, 22.4% two mycotoxins, and 9.9% of the samples showed contamination by only one mycotoxin. The significant prevalence of mycotoxins of the Fusarium and Aspergillus genera in the samples of the present study indicates a notable degree of pre- and post-harvest contamination in these beef cattle diets. Further studies are needed to define methods for monitoring cattle exposure to clarify its effects, even at low levels, and reduce the impacts on beef cattle production in Brazil.

Mycotoxins are toxic fungi secondary metabolites that develop on feedstuffs and can be transferred into milk, thus representing a public health risk. The objective of this study was to assess the co-occurrence of mycotoxins in the diet and in the milk of dairy cows from the southeast region of Brazil. Samples of total mixed ration (TMR, n = 70) and milk (n = 70) were collected in dairy farms and subjected to multi-mycotoxin analysis using liquid chromatography coupled to tandem mass spectrometry. The aflatoxins (AFs), ochratoxin A (OTA), and T-2 and HT-2 toxins were not detected in TMR samples. In contrast, fumonisins (FBs), zearalenone (ZEN), and deoxynivalenol (DON) were detected in 100, 93, and 24% of TMR samples at mean levels of 336.7 ± 36.98, 80.32 ± 16.06 µg/kg and 292.1 ± 85.68 µg/kg, respectively. Ninety-two percent of TMR samples exhibited co-occurring mycotoxins. In milk, 54% of samples (n = 38) had detectable levels of mycotoxin, while 43% (n = 30) contained two or more types of mycotoxins. DON, FB, and ZEN metabolites (α-zearalenol and β-zearalenol) were the most frequent mycotoxins detected in the milk samples analyzed, at mean concentrations of 0.562 ± 0.112, 2.135 ± 0.296 µg/kg, 2.472 ± 0.436 µg/kg, and 0.343 ± 0.062 µg/kg, respectively. However, none of the analyzed milk samples had levels higher than the maximum permitted limit for AFM₁ in Brazil (0.5 µg/L). The results of this trial highlight the concern about the co-occurrence of multiple mycotoxins in TMR and in milk, due to the possible additive or synergistic effects of these compounds. The presence of co-occurring mycotoxins in milk underscores the need for stringent preventive practices to avoid mycotoxin contamination in the diet of dairy cows in Brazil.

Biological decontamination strategies using microorganisms to adsorb aflatoxins have shown promising results for reducing the dietary exposure to these contaminants. In this study, the ability of inactivated biomasses of Lacticaseibacillus rhamnosus (LRB) and Saccharomyces cerevisiae (SCB) incorporated alone or in combination into functional yogurts (FY) at 0.5–4.0% (w/w) to adsorb aflatoxin B₁ (AFB₁) was evaluated in vitro. Higher adsorption percentages (86.9–91.2%) were observed in FY containing 1.0% LR + SC or 2.0% SC (w/w). The survival of mouse embryonic fibroblasts increased after exposure to yogurts containing LC + SC at 1.0–4.0% (w/w). No significant differences were noted in the physicochemical and sensory characteristics between aflatoxin-free FY and control yogurts (no biomass) after 30 days of storage. The incorporation of combined LRB and SCB into yogurts as vehicles for these inactivated biomasses is a promising alternative for reducing the exposure to dietary AFB₁. The results of this trial support further studies to develop practical applications aiming at the scalability of using the biomasses evaluated in functional foods to mitigate aflatoxin exposure.

The aim of this study was to conduct an up-to-date investigation on the occurrence levels of aflatoxin M₁ (AFM₁) in samples of raw milk (n = 40), pasteurized milk (n = 44), ultra-high temperature (UHT) milk (n = 27), Minas cheese (n = 57), and yogurt (n = 44) traded in São Paulo state, Brazil. AFM₁ was extracted from fluid milks and dairy products using immunoaffinity columns and determined by high performance liquid chromatography. AFM₁ was detected at the mean level of 0.080 ± 0.071 µg/L or kg in 72 samples (34.0%) evaluated in the study (n = 212). Detectable levels of AFM₁ were observed in five samples of raw milk (12.5%), 16 samples of pasteurized milk (36.4%), 13 samples of UHT milk (48.1%), 27 samples of cheese (47.4%), and 11 samples of yogurt (25.0%), although none of them had concentrations above the maximum permitted levels (MPL) for AFM₁ adopted in Brazil. However, 11.7% (n = 13) of samples of raw, pasteurized, and UHT milks would have AFM₁ concentrations above the MPL of 0.05 μg/L adopted in the EU. The maximum level was detected in one cheese sample containing 0.695 µg/kg. Although none of the samples exceeded the Brazilian MPL, the high frequencies of AFM₁ in Brazilian milk products warrant concern about their contribution to the human exposure to aflatoxins. Because aflatoxins are among the most potent carcinogens known, the results of this trial stress the need for stringent measures in the milk production system to avoid AFM₁ in milk and derived products.