Determination of serum aflatoxin B1-lysine and biochemical parameters in broiler chicks fed an aflatoxin B1-contaminated diet.

In the present trial, the levels of serum aflatoxin B1 (AFB1)-lysine and their relationship with biochemical parameters in broiler chicks fed an AFB1-contaminated diet were determined. The experimental design was completely randomized with two treatments (control and 222.17 µg/kg AFB1) and 20 bird per treatment. Feeds were offered to broiler chicks for 14 days, from 28 to 42 days of age. Animals were vaccinated against Newcastle's and Marek's diseases on the 14th day of life, and were killed at 42 days of age. Broilers receiving AFB1 did not demonstrate any sign of toxicity. Compared with controls, aspartate aminotransferase and globulin levels were not affected in the AFB1-treated group. However, higher levels of gamma-glutamyl transferase and lower concentrations of total protein and albumin were observed in the group receiving AFB1 on days 35 and 42. AFB1-lysine were detected in the serum of all broilers fed the AFB1-contaminated diet, at mean levels of 56.52-77.83 ng/mg albumin on days 35 and 42 of age, respectively. These values indicated the internal dose of AFB1 in birds, which negatively correlated with total protein, albumin, and globulin levels. Data indicated that AFB1-lysine shows the potential to be a sensitive and specific biomarker for the evaluation of broiler exposure to dietary aflatoxin, as well as for diagnostic purposes. Further studies are necessary to determine physiologically-based toxicokinetics of serum AFB1-lysine in broilers.

Effects of different sources of Saccharomyces cerevisiae biomass on milk production, composition, and aflatoxin M1 excretion in milk from dairy cows fed aflatoxin B1.

The aim of the present study was to evaluate the effect of different sources of Saccharomyces cerevisiae (SC) biomass (20.0 g/d) obtained from sugarcane (cell wall, CW; dried yeast, DY; autolyzed yeast, AY) and the beer industry (partially dehydrated brewery yeast, BY) on milk production, fat and protein percentages, and aflatoxin M1 (AFM1) excretion in milk from dairy cows receiving 480 µg aflatoxin B1 (AFB1) per day. A completely randomized design was used with 2 lactating cows assigned to each of 10 dietary treatments, as follows: negative controls (no AFB1 or SC-based biomass), positive controls (AFB1 alone), DY alone, DY + AFB1, BY alone, BY + AFB1, CW alone, CW + AFB1, AY alone, and AY + AFB1. The cows in the aflatoxin treatment group received AFB1 from d 1 to 6, while the SC biomass was administered with the AFB1 bolus from d 4 to 6. Aflatoxin B1 or SC-based products did not affect milk production or milk composition during the experimental period. Aflatoxin M1 was detected in the milk from all aflatoxin treatment group cows, reaching maximum levels at d 3 and varying from 0.52 ± 0.03 to 1.00 ± 0.04 µg/L. At end of the treatment period, CW, AY, DY, and BY removed 78%, 89%, 45%, and 50% of AFM1 from the milk, respectively, based on the highest level found on d 3. Results indicate a potential application of industrial fermentation by-products, especially CW and AY, as a feed additive in the diets of dairy cows to reduce the excretion of AFM1 in milk.

Fumonisin B1 in cereal mixtures marketed in Brazil.

The aim of this study was to detect and quantify fumonisin B1 (FB1) in cereal mixtures marketed in Brazil. Fifteen samples from different lots were acquired each month by internet from supermarkets during seven months, adding up to 105 analysed samples. The unit sample constituted of an original package with a minimum of 250 g. Extraction and clean-up of samples for FB1 determination were carried out using immunoaffinity columns. Identification and quantification of FB1 were performed by high performance liquid chromatography. Eighty-eight (83.8%) samples were contaminated with FB1 and four (3.8%) presented levels above 500 µg kg(-1) (634, 703, 1269 and 1876 µg kg(-1)). Maximum FB1 + FB2 levels allowed by Brazilian regulations will reach 1500 µg kg(-1) for corn flour in 2016 and 1000 µg kg(-1) for others corn products. This study showed that even at levels below the legislative limits, human exposure to this toxin can occur constantly.

Assessment of dietary intake of fumonisin B1 in São Paulo, Brazil.

In this study, fumonisin B1 (FB1) consumption was assessed through determination of FB1 in corn meal, corn flour, corn flakes, polenta, canned corn and popcorn collected from homes of residents of Pirassununga, São Paulo, Brazil, and using a Food Frequency Questionnaire (FFQ) filled out by the residents. One hundred and twenty samples were collected from 39 residents on four separate occasions. FB1 was determined by high performance liquid chromatography using a validated method that uses SAX column clean-up. The highest levels of FB1 were found in corn meal at a mean concentration of 474.6 µg kg(-1). However, none of the samples tested for FB1 had levels above the tolerance limit established in Brazil. The mean probable daily intake (PDIM) of FB1 was 63.3 ng kg(-1)body weight day(-1), which is approximately 3% of the provisional maximum tolerable daily intake (PMTDI) recommended for fumonisins.

Survey of aflatoxin M1 in cheese from the North-east region of São Paulo, Brazil.

In the present study, 24 samples of Minas Frescal cheese and 24 samples of Minas Padrão cheese produced in the North-east region of the state of São Paulo, Brazil, were analysed for aflatoxin M1 (AFM1) by high-performance liquid chromatography (HPLC) between March and August 2008. AFM1 was detected in 13 (27.1%) samples at concentrations ranging from 0.037 to 0.313 ng g⁻¹. The mean concentrations of AFM1 in positive samples of Minas Frescal and Minas Padrão cheese were 0.142 ± 0.118 and 0.118 ± 0.054 ng g⁻¹, respectively. It is concluded that the incidence of AFM1 in Minas cheese may contribute to an increase in the overall ingestion of aflatoxins in the diet, hence indicating the need for the adoption of a tolerance limit for AFM1 in cheese in Brazil.

Aflatoxins and cyclopiazonic acid in feed and milk from dairy farms in São Paulo, Brazil.

The occurrence of aflatoxins (AF) B1, B2, G1, G2 and cyclopiazonic acid (CPA) in feeds, and AFM1 and CPA in milk was determined in dairy farms located in the northeastern region of São Paulo state, Brazil, between October 2005 and February 2006. AF and CPA determinations were performed by HPLC. AFB1 was found in 42% of feed at levels of 1.0-26.4 µg kg(-1) (mean: 7.1 ± 7.2 µg kg(-1)). The concentrations of AFM1 in raw milk varied between 0.010 and 0.645 µg l(-1) (mean: 0.104 ± 0.138 µg l(-1)). Only one sample was above the tolerance limit adopted in Brazil (0.50 µg l(-1)) for AFM1 in milk. Regarding CPA in feed, six (12%) samples showed concentrations of 12.5-153.3 µg kg(-1) (mean: 57.6 ± 48.7 µg kg(-1)). CPA was detected in only three milk samples (6%) at levels of 6.4, 8.8 and 9.1 µg l(-1). Concentrations of aflatoxins and CPA in feed and milk were relatively low, although the high frequency of both mycotoxins indicates the necessity to continuously monitor dairy farms to prevent contamination of feed ingredients.