The transfer of aflatoxin M1 in milk of ewes fed diet naturally contaminated by aflatoxins and effect of inclusion of dried yeast culture in the diet

Abstract

An experiment was carried out to investigate 1) the transfer of aflatoxin M1 (AFM1) into the milk of dairy ewes fed diets naturally contaminated with aflatoxin B1 (AFB1); 2) the effect of the addition of dried yeast culture in the diet on this transfer; and 3) the alteration of enzymatic activities in the liver of ewes fed diets contaminated with AFB1. Twenty-four Sarda dairy ewes were divided in 4 groups and fed a concentrate mix containing 4 amounts of wheat meal naturally contaminated with aflatoxins. The diet of the control group had no wheat meal, whereas that of treated groups had low, medium, or high amounts of contaminated wheat, which corresponded to 1.13, 2.30, and 5.03 microg of AFB1/kg of feed, respectively. The experiment lasted 14 d. On d 8 to 14 from the beginning of the trial, 12 g/d of a commercial dried yeast product (DYP) of Kluyveromyces lactis was added to the diet of each ewe. The AFM1 concentration in individual milk samples and the blood serum metabolites were measured periodically. The presence of AFM1 was first detected in milk on d 1 of administration, and then its concentration increased and approached a steady-state condition on d 3 simultaneously in all treated groups. The AFM1 in milk at the steady-state condition, which was linearly related to the AFB1 intake, was 39.72, 50.38, and 79.29 ng/L in the low-aflatoxin, medium-aflatoxin, and high-aflatoxin groups, respectively. The AFM1 concentration in milk of the high-aflatoxin group was approximately 1.5-fold greater than the European Commission maximum tolerance level (50 ng/kg). The addition of DYP to the diet did not affect the AFM1 concentration in milk. After the withdrawal of the contaminated concentrate mix, the AFM1 mean concentrations decreased quickly and were no longer detected after 3 d in all treated groups. Daily milk yield and composition did not differ because of aflatoxin treatment. Blood serum parameters (creatinine, glutamic oxalacetic transaminase, glutamic pyruvic transaminase, gamma glutamyl transferase, alkaline phosphatase, lactate dehydrogenase, cholesterol, protein, urea, calcium, and phosphorus) were not influenced by AFB1 intake. Therefore, the effect of DYP on certain blood parameters (gamma glutamyl transferase, urea, creatinine, and calcium) could not be attributed to amelioration of the aflatoxin-contaminated diet. In conclusion, diet contamination by AFB1 near the European Union tolerance level (0.005 mg/kg) in complete feed for dairy animals (e.g., high-aflatoxin group) can result in an AFM1 milk concentration higher than the European Commission maximum tolerance level. Transfer of aflatoxin from feed to milk was not affected by dietary addition of a commercial DYP.

Modification of aflatoxin B1and ochratoxin A toxicokinetics in rats administered a yeast cell wall preparation

“…In addition, it has been described that for a same strain the 22 growth conditions and the preparation process influence the adsorption capacity of yeast cell wall additives (Pradelles et al 2008). The inconsistency between studies, however, could also 24 be due to other reasons such as the mode of incorporation of the preparation into the diet or by the type of feed and mycotoxin present (Battacone et al 2009;Blank, Wolffram 2009;26 Masoero et al 2009). Trials involving domestic animals involve many variables which are difficult to control between studies.…”

Sensitive competitive direct enzyme-linked immunosorbent assay and gold nanoparticle immunochromatographic strip for detecting aflatoxin M1 in milk

“…Aflatoxin B1 (AFB1), has the highest toxicity among all aflatoxins. The major hydroxylated metabolite of AFB1 is aflatoxin M1 (AFM1), which is found in the milk and blood of animals ingesting AFB1-containing feed (Battacone, Nudda, Palomba, Mazzette, & Pulina, 2009;Sabino, Purchio, & Milanez, 1995). AFM1 concentrations that appear in milk are approximately 0.5e5% of ingested AFB1, While remaining stable during milk pasteurization and heat treatment, it can also be found in milk-derived dairy products.…”

Aflatoxins M1 and M2 in the milk of donkeys fed with naturally contaminated diet

“…This carryover AFM1 value was lower compared with that found in other species, which ranged from 0.06% in sow, 0.2% in buffalo, 1.8% in goats, 2.90% in sheep to 6.6% in cows Pietri et al 2003;Ronchi et al 2005;Battacone et al 2009;Britzi et al 2013). The AFM1 carryover appears to be clearly influenced by the animal species; in particular, the carryover in monogastric animals seems to be lower than that found in ruminants.…”