MYCOTOXINS IN DAIRY COWS

Traditionally, ruminants have been considered less sensitive to mycotoxins than monogastric animals. While it is true that the rumen partially degrades some mycotoxins, this is not the case with others, such as aflatoxins.

Chronic exposure of dairy cows to aflatoxins reduces performance, impairs reproduction, compromises immune function, and increases vulnerability to diseases (Yiang, 2021). That is to say, it supposes an impact in the physiology of the animals, and therefore in the economy of the dairy farms.

On the other hand, since 1988 the WHO considers Aflatoxin B1 as a human carcinogen and Aflatoxin M1 as a possible carcinogen. A part of the Aflatoxin B1 is transformed into M1, and it is excreted through milk. That means, that the population that consumes milk is exposed to it. For this reason, governments have set limits: for example, in the EU Aflatoxin B1 cannot exceed 0.05 µg/kg in milk, and 0.025 µg/kg in infant milk; while in the USA its presence is limited to 0.5 µg/kg in milk. Dairy cattle farms must comply with these limits.

There are few ways to reduce the aflatoxin exposure for cattle, but the most effective one is the use of mycotoxin binders. To evaluate their effectiveness against Aflatoxins B1 and M1, different tests were carried out:

An in vitro test was carried out with Toxinor at 0.5% dosage, with 2 mg/kg of mycotoxins. At a pH of 4, it was possible to eliminate 99.86% of Aflatoxin B1 and 100% of Aflatoxin M1, with very similar results at pH 7, where 99.64% of Aflatoxin B1 was eliminated, and 100% of Aflatoxin M1. That is, Toxinor eliminated almost all Aflatoxin B1 and M1 in vitro.

An in vivo test was also carried out to evaluate the efficiency of Toxifree against AFM1: a test was carried out in a herd of 720 lactating cows affected by Aflatoxin M1. A dose of 0.5% of Toxifree in feed was used, and in two weeks the presence of AFM1 (µg/kg) was reduced from 0.45 µg/kg to 0.02 µg/kg, which placed it within the legal limits. In addition, milk production increased by 5%.

Mycotoxin binders prove, both in vivo and in vitro, to be effective additives in the management of Aflatoxins B1 and M1 in dairy cattle, which improves the economic figures of dairy cattle farms, ensuring compliance with the legislation. Also, can be included both the concentrate and the total mixed ration on the farm itself.