Effects of chronic low-dose aflatoxin B exposure in lactating Florida dairy goats.

In the past few years there has been a growing trend in the prevalence of aflatoxins, attributable to climate change, in substances destined for animal feeding, together with an increase in dairy product consumption. These facts have triggered great concern in the scientific community over milk pollution by aflatoxin M. Therefore, our study aimed to determine the transfer of aflatoxin B from the diet into milk as AFM in goats exposed to different concentrations of AFB, and its possible effect on the production and serological parameters of this species. For this purpose, 18 goats in late lactation were divided into 3 groups (n = 6) and exposed to different daily doses of aflatoxin B (T1 = 120 µg; T2 = 60 µg, and control = 0 µg), during 31 d. Pure aflatoxin B was administered 6 h before each milking in an artificially contaminated pellet. The milk samples were taken individually in sequential samples. Milk yield and feed intake were recorded daily, and a blood sample was extracted on the last day of exposure. No aflatoxin M was detected, either in the samples taken before the first administration, or in the control group ones. The aflatoxin M concentration detected in the milk (T1 = 0.075 µg/kg; T2 = 0.035 µg/kg) increased significantly on a par with the amount of aflatoxin B ingested. The amount of aflatoxin B ingested did not have any influence on aflatoxin M carryover (T1 = 0.066% and T2 = 0.060%), these being considerably lower than those described in dairy goats. Thus, we concluded that the concentration of aflatoxin M in milk follows a linear relationship with respect to the aflatoxin B ingested, and that the aflatoxin M carryover was not affected by the administration of different aflatoxin B doses. Similarly, no significant changes in the production parameters after chronic exposure to aflatoxin B were observed, revealing a certain resistance of the goat to the possible effects of that aflatoxin.