Mycotoxin contamination of diets for beef cattle finishing in feedlot

Abstract

The objective of this survey was to identify what mycotoxins were present in ingredients used in diets offered to beef cattle in feedlots and their concentrations. The survey covered 30 Brazilian feedlots located in the five major beef-producing states. Samples of total mixed ration (TMR) and ingredients were collected and analyzed for mycotoxin using ultra-performance liquid chromatography coupled to tandem mass spectrometry. Mycotoxin concentrations were further interpreted according to known species-specific sensitivities and normalized according to the principles of toxic equivalent factors (risk equivalent quantities-REQ) expressed in µg kg −1 of aflatoxin B1-equivalent. Forty percent of the visited feedlots had apparent fungi in TMR. However, only one feedlot (3%) used a mycotoxin adsorbent. On the other hand, diets with high contamination presented no apparent fungi. One hundred percent of TMR was contaminated. All samples presented at least one mycotoxin contamination, with 65.5% considered low contamination, 27.6% medium contamination, and 6.90% high contamination. The toxins identified in TMR were fumonisins (most frequently), trichothecenes A, trichothecenes B, fusaric acid, aflatoxins, and ergot (mean concentration values: 2,330, 104.3, 79.5, 105, 10.5, and 5.5 µg kg −1 , respectively). According to the contamination of TMR samples per region, Mato Grosso do Sul state presented the highest contaminations. Peanut meal was the most contaminated ingredient. One hundred percent of TMR in Brazilian feedlot is contaminated. Fumonisins were the mycotoxin most frequent and at highest concentrations in TMR samples. Moreover, mycotoxin concentrations have a distinct pattern among ingredients, TMR, and feedlots (local).

Co-Occurrence of Regulated and Emerging Mycotoxins in Corn Silage: Relationships with Fermentation Quality and Bacterial Communities

“…The presence of DON and fusaric acid in vitro caused depression of both Ruminococcus albus and Methanobrevibacter ruminantium microbial activity, whereas these effects were not observed in the presence of DON alone [ 54 ]. Custódio et al [ 55 ] found levels of fusaric acid in corn silage used in beef cattle diets of 619 µg/kg with high incidence (i.e., 80%). The same authors highlighted that fusaric acid increased toxicity of other Fusarium -produced toxins through a synergistic mechanism [ 1 ] and this required further studies to be completely elucidated.…”

Effects of experimental exposure to zearalenone on reproductive system morphometry, plasma oestrogen levels, and oocyte quality of beef heifer

“…The total digestible nutrient (TDN), crude protein (CP) and neutral detergent fibre (NDF) were 675, 115 and 426 g/kg of total diet, respectively, as shown in table 1. The addition of ZEA was carried out based on total diet, as reported previously (Custódio et al, 2019); however, the administered dose was considerably less than the lethal dose for cattle, as reported by Chang et al (2017) (4,000 mg•kg -1 BW). The 14-d adaptation period was followed by 12 weeks of evaluation during the dry season of 2019 (from May to August) as shown in Figure 1.…”

Cocktails of Mycotoxins, Phytoestrogens, and Other Secondary Metabolites in Diets of Dairy Cows in Austria: Inferences from Diet Composition and Geo-Climatic Factors

“…Several studies have analysed the occurrence of some mycotoxins in different types of feed ingredients, including in pastures, cereals, and silages [ 6 , 7 , 22 , 42 , 47 , 48 , 49 ]. Research on the incidence of mycotoxins and other fungal secondary metabolites in complete diets (i.e., TMR) of cattle has been carried out during the last decade; however, it is still scarce [ 50 , 51 , 52 , 53 , 54 , 55 , 56 ]. Targeting the dietary levels of toxins and endocrine-disrupting metabolites is vital to assessing the risks for impacts on health, reproduction, and production [ 10 , 24 ].…”