Mycotoxins are toxic secondary metabolites produced by a variety of fungi, which when ingested can cause several deleterious effects to the health of humans and animals. In this work, the detection and quantification of six major mycotoxins (aflatoxins—AFLA, deoxynivalenol—DON, fumonisins—FUMO, ochratoxin A—OTA, T-2 toxin—T-2 and zearalenone—ZON) in 1749 samples of feed and feed ingredients for cattle, collected in Brazil between 2017 and 2021, was carried out using enzyme-linked immunosorbent assay (ELISA). In total, 97% of samples were contaminated with at least one mycotoxin, yet, very few samples exceeded the lowest European Union guidance values for cattle, and the estimated daily intake also showed a low risk for the animals. However, co-occurrences were widely observed, as 87% of samples contained two or more mycotoxins at the same time, and the presence of more than one mycotoxin at the same time in feed can lead to interactions. In conclusion, the contamination of feed and feed ingredients for cattle with mycotoxins in Brazil is very common. Hence, the monitoring of these mycotoxins is of significant importance for food safety.

Aspergillus carbonarius is a saprobic filamentous fungus, food spoiling fungus and a producer of ochratoxin A (OTA) mycotoxin. In this study, the in vitro antifungal activity of neem oil (0.12% p/p of azadirachtin) was evaluated against the growth of six strains of A. carbonarius and the production of OTA. Four different concentrations of neem oil were tested in addition to three incubation times. Only the concentration of 0.3% of neem oil inhibited more than 95% of the strain’s growth (97.6% ± 0.5%), while the use of 0.5% and 1.0% of neem oil showed lower antifungal activity, 40.2% ± 3.1 and 64.7% ± 1.1, respectively. There was a complete inhibition of OTA production with 0.1% and 0.3% neem oil in the four strains isolated in the laboratory from grapes. The present study shows that neem essential oil can be further evaluated as an auxiliary method for the reduction of mycelial growth and OTA production.

Nanoparticles (NPs) are nanoscaled particles sized from 1–100 nm, which can be composed of inorganic or organic compounds. NPs have distinctive morphology, size, structure, and surface features, which give them specific properties. These particular attributes make them interesting for biological and medical applications. Due to these characteristics, researchers are studying the possible aptness of numerous nanoparticles in veterinary medicine, such as the capacity to act as a drug delivery system. The use of these NPs as a possible bactericidal or bacteriostatic medication has been studied against different bacteria, especially multiresistant strains and the ones that cause mastitis disease. The antibiofilm property of these nanostructures has also already been proved. The antiviral activity has also been shown for some important viral animal diseases; the antifungal activity had been demonstrated against both pathogenic and mycotoxigenic species. Therefore, this review aimed to elucidate the main clinical and preventive veterinary applications of inorganic and organic nanoparticles.

The effect of essential oils (obtained using hydrodistillation) and plant extracts (ethanolic, aqueous, and hexanic extractions) of 10 different plants cultivated in Brazil were tested using the diffusion agar method, with the objective of evaluating the inhibitory effect of the oils and extracts on the mycelial growth of Aspergillus westerdijkiae NRRL 3174 and A. carbonarius RC 2054 (UNRC). Of the 40 essential oils and plant extracts analyzed, oregano essential oil and plant extract, rosemary essential oil, and the clove ethanolic extract were the best choice to obtain the growth parameters (radial growth rates (mm day⁻¹) and lag phase (h)) due the good results presented and the volume of oil/extract obtained. Comparing all the essential oils and plant extracts that were tested for growth parameters, the best results were obtained for the clove ethanolic extract for both strains assayed. These results demonstrated an outstanding potential use of some of these products in prevention of fungal contamination in food. However, further studies need to be conducted to determine the ability of these oils and extracts to inhibit or reduce ochratoxin A production.

Residual feed intake (RFI) is a metric to identify high feed efficient (negative RFI; -RFI) and low feed efficient (positive RFI; +RFI) animals within and across cohorts. The objective of this study was to quantify and determine potential differences between the most RFI divergent cows in (1) metabolites, hormones, and fatty acids in tail vessel and mammary vein blood; (2) hepatic gene expression; (3) CH₄, CO₂, O₂, and related metrics; and (4) hepatic mitochondrial function. Mid-lactation Holstein dairy cows (n = 64/trial) were enrolled in two 8-wk trials to quantify intake, BW, and milk production. The top and bottom 25% (n = 64; analyzed for all variables) and the most divergent 15% (n = 19; additional analysis of gene expression, mitochondrial function, and gas emissions and consumption) RFI subgroups were analyzed across the trials. Milk yield and milk energy output were similar, but milk lactose percentage was greater and MUN and SCS was lower in -RFI cows than +RFI cows. Tail vessel concentrations of C16:0, C16:1 cis, C17:0, C18:0, and C22:0 were (or tended to be) greater, and mammary vein C16:1 cis and C18:1 cis were greater in -RFI cows than +RFI cows. Mammary vein BUN was lower and tail vessel insulin concentration tended to be greater in -RFI cows than +RFI cows. Expression of uncoupling, mitochondrial, or tricarboxylic acid cycle genes were similar across RFI status. Mitochondrial complex IV, when quantified with complex I substrate, had lower oxygen consumption rates in -RFI cows than +RFI cows. Emissions of CH₄ and overall CO₂ were lower in -RFI cows than +RFI cows. Overall, mitochondrial function and nutrient partitioning differed in dairy cows of divergent RFI status, although differences did not appear to be due to changes in hepatic gene expression.

This study aimed to evaluate the microbiological quality of Brazilian dry-cured loin (Socol), as well as the presence of ochratoxin A (OTA) and its synthesis by the isolated Aspergillus ochraceus complex under different conditions (culture media, temperature, and time of incubation). Nine bacterial genera were isolated and identified by Matrix Assisted Laser Desorption Ionization—Time Of Flight/Mass Spectrometry (MALDI-TOF/MS), including Serratia spp. (32.4%), Citrobacter spp. (20.9%), Enterobacter spp. (13.6%), and Staphylococcus spp. (6.3%), among others. Salmonella spp. was not observed, and counts of thermotolerant coliforms and coagulase-positive Staphylococcus were below the confidence level. Fifteen fungal strains were isolated and identified as Aspergillus spp. (n = 5), Cladosporium sp. (n = 1), and Penicillium spp. (n = 9). OTA was quantified in Socol samples, and the enumeration of fungi showed a correlation (r = 0.77) with the mycotoxin detection. A. ochraceus complex produced OTA in Czapek Yeast Autolyzed (CYA) and Yeast Extract Sucrose (YES) agars at different times and temperatures. It was concluded that the microbiota of Socol is complex, encompassing spoilage bacteria. Undesirable fungi are also present, including those belonging to the A. ochraceus complex that produce OTA.