Bovine Colostrum Silage: Physicochemical and Microbiological Characteristics at Different Fermentation Times.

Bovine colostrum silage (BCS) is a technique used by milk producers for the conservation of bovine colostrum. However, it is necessary to ensure the safety and quality of BCS, as this food will be supplied to the animals. This study aimed to compare the physicochemical and microbiological compositions of colostrum silage at different fermentation times with milk and bovine colostrum (BC) quality parameters. BC samples were obtained from Jersey animals from one dairy farm. The BC samples (n = 21) were placed in 500-mL plastic bottles, stored vertically and anaerobically fermented for periods of 61-437 days. The following parameters of the physicochemical composition of the BCS were evaluated: acidity, protein, total solids and ash, using the methodologies of Adolfo Lutz Institute (2008). The microbiological analysis was developed according to the methodology proposed by Saalfeld et al. (2013), with adaptations. The acidity, total solids and protein over fermentation time (group 1: 61 to 154, group 2: 200 to 273, and group 3: 280 to 437 days) were not significantly different (P > 0.05). The ash content was significantly different (P < 0.05) in groups 1 and 3 and showed a decrease (moderate negative correlation of -0.63) with increasing fermentation time. Positive correlations were observed between total solids and the protein and ash contents. The genus of microorganisms with the highest occurrence was Lactobacillus spp. (95.2% of BCS) and those of lesser occurrence included Escherichia spp., Actinomadura spp., Streptococcus spp. and Leuconostoc spp. (4.8% of BCS). BCS has a physicochemical composition similar to BC and showed changes during the fermentation period; however, the presence of pathogenic microorganisms in BCSs reinforces the need to further explore the quality parameters for BCS to ensure the safety of animals who receive this food.

Mycotoxin and fungicide residues in wheat grains from fungicide-treated plants measured by a validated LC-MS method.

Wheat (Triticum aestivum) is an annual crop, cultivated in the winter and spring and susceptible to several pathogens, especially fungi, which are managed with fungicides. It is also one of the most consumed cereals, and can be contaminated by mycotoxins and fungicides. The objective of this study was to validate an analytical method by LC-MS for simultaneous determination of mycotoxins and fungicide residues in wheat grains susceptible to fusarium head blight treated with fungicides, and to evaluate the relationship between fungicide application and mycotoxin production. All parameters of the validated analytical method were within AOAC and ANVISA limits. Deoxynivalenol was the prevalent mycotoxin in wheat grain and epoxiconazole was the fungicide residue found in the highest concentration. All fungicidal treatments induced an increase in AFB2 production when compared to the control (without application). AFB1 and deoxynivalenol, on the contrary, were reduced in all fungicide treatments compared to the control.

Fungicides and the effects of mycotoxins on milling fractions of irrigated rice.

This study aimed to evaluate the effect of fungicides on rice cultivation, regarding the occurrence and the distribution of mycotoxins in fractions of the processed grain, by a validated chromatographic method. A method based on extraction with acetonitrile:water, determination by HPLC-DAD, and confirmation by LC-MS was validated before the mycotoxin evaluation. Control samples and samples to which triazole fungicides had been applied were collected from experimental fields for four years. Results showed that 87% of the samples were contaminated with deoxynivalenol or zearalenone, and that all samples treated with fungicide were contaminated with some of these mycotoxins. Aflatoxin B(1) and ochratoxin A were found in 37% of the samples; half of them had been treated with fungicide. Therefore, fungicides tend to be stressors for toxigenic fungi found in the fields.

Incidence of aflatoxin M1 in fresh milk from small farms

Abstract The objective of this work was to determine aflatoxin M1 in fresh milk from fifty-two small farms in the city of Concórdia - SC, Brazil. Samples from the cooling tanks of each property were collected from November 2014 to January 2015. The QuEChERS method was used for the extraction of aflatoxin M1, and quantification was performed in UHPLC-FL. 40.4% of the analyzed samples (eg, 21 samples) showed contamination levels by aflatoxin M1 above the maximum limit allowed by the Brazilian regulation, which is 0.5 μg L-1. These results suggest the importance of implementing Good Practices in obtaining feed for dairy cows, since the contamination of milk by aflatoxin M1 occurs through the biotransformation of aflatoxin B1, after the ingestion of feed or silage contaminated by the animals, posing risk to the animals themselves, as well as to consumers of milk and dairy products.