Measurement of urinary zearalenone concentrations for monitoring natural feed contamination in cattle herds: On-farm trials1

Abstract

The aims of the present study were to investigate the efficacy of measuring bovine urinary zearalenone (ZEN) concentrations by using a commercially available ELISA method in cattle kept under different feeding conditions to monitor the natural contamination of feeds at the farm level, and to investigate the effects of supplementation of a mycotoxin adsorbent (MA) product in the feed based on urinary ZEN concentration. First, Japanese Black cattle herds kept for breeding (4 herds) and fattening (4 herds) purposes were provided with similar feeding conditions. Then, urinary samples from 5 cows in each herd were collected and analyzed. Second, dairy cows from 1 herd fed with total mixed rations (TMR) were selected. After thorough mixing of the MA (40 g/d) with TMR, the supplemented TMR was fed according to the following schedule: with MA for 2 wk, without MA for 3 wk; then with MA for 2 wk and without MA for 6 wk. Urine samples were collected from cows (n = 6 to 7) and examined before and after each interval. Zearalenone concentrations were measured by the ELISA and liquid chromatography-tandem mass spectrometry methods. The concentration of ZEN and its metabolites was expressed after creatinine (Crea) correction [ZEN or metabolites (pg/mL)/Crea (mg/dL); pg/mg of Crea]. In the first experiment, the urinary concentrations of ZEN and its metabolites were variable in all herds, and significant differences were observed between herds. In 1 fattening herd, in particular, urinary ZEN concentrations were greater (P < 0.001) than in the other 3 herds. This might reflect significant natural ZEN contamination of the feed at the farm level. In Exp. 2, urinary ZEN concentrations displayed peculiar trends after supplementation with MA. After 2 wk of supplementation, a significant decrease of ZEN (P < 0.05) was observed. Zearalenone concentrations remained at a reduced amount during 3 wk without MA supplementation and 2 wk with MA supplementation. When MA was not added to the feed for the next 6 wk, the concentrations increased to the original quantity. These findings indicate the usefulness of measuring concentrations of urinary ZEN and its metabolites not only for monitoring the natural ZEN contamination of cattle feed at the farm level but also for in vivo evaluation of MA function after supplementing feeds with MA.

Monitoring natural feed contamination in beef cattle by measurements of urinary zearalenone concentrations after oral administration of mycotoxin adsorbents as a top dressing

“…In our previous study (Takagi et al 2011), it was clearly indicated that MA-A supplemented as TMR (theoretically equally mixed with the feed diets) was effective in preventing the adsorption of ZEN from the intestines of dairy cattle. Thus, as a preliminary study, we examined whether the method of supplementing MA within the feed diets may have an effect on the urinary concentrations of ZEN and its metabolites.…”

“…Firstly, it was assumed that the method used to supply the MA into the feeds might have a significant effect on the extent of absorption of mycotoxin from gastrointestinal tracts. However, MA supplementation revealed that it was not possible to adsorb ZEN and its metabolites completely from naturally contaminated feeds, even if supplied with a maximum dose of MA to the TMR for a period exceeding 2 weeks as recommended by the manufacturer (Takagi et al, 2011). Although we cannot simply compare the total ZEN concentrations between our previous and present studies because of the differences of breed of cattle and body weights, the minimal concentration of total ZEN in previous report was approximately 400 pg/mg Crea as determined by ELISA and 100 pg/mg Crea as determined by LC/MS/MS.…”

“…To confirm the concentrations of ZEN measured by ELISA, and to measure the ZEN metabolites in bovine urine, the urine samples measured by ELISA were reanalysed by LC-ESI/MS/MS (Takagi et al 2011).…”

“…After centrifugation at 500)g for 10 min, the samples were frozen at Á308C until analysis. The urinary ZEN concentration was measured by ELISA (Takagi et al 2011). Additionally, for confirmation, concentrations of urinary ZEN, a-ZOL and b-ZOL were measured by LC/MS/MS, and the ZEN/Crea ratio was finally determined.…”

“…Among these approaches, supplementation of feed with mycotoxin adsorbents (MAs) has been recognised as an effective and practical addition to the animal production industry (Sabater-Vilar et al 2007;Kutz et al 2009). Recently, we reported the efficacy of monitoring urinary zearalenone concentrations in cattle herds at the farm level, and indicated that there is a significant reduction of urinary ZEN concentration concomitant with the reduction of somatic cell counts during the period of supplementation of total mixed rations in a dairy cattle herd (Takagi et al 2011). However, recent reports clearly indicated that not all MA products are equally effective for preventing mycotoxin absorption from the digestive tract (Kutz et al 2009), which suggested the possibility that types of MAs as well as the methods of applying MAs might have an affect on the absorption of mycotoxin in the digestive tract (Kutz et al 2009).…”