[Show abstract][Hide abstract] ABSTRACT: To investigate the effects of supplementation of mycotoxin adsorbents (MAs) in top dressing of cattle feed with respect to concentrations of urinary zearalenone (ZEN) and its metabolites, α-zearalenol (α-ZOL) and β-zearalenol (β-ZOL), Japanese Black cattle herds for breeding (2 herds) and fattening (2 herds) were provided with similar feeding conditions. Two types of MAs were tested and the maximal recommended dose of each MA was supplemented in the feed as a top dressing for 2 weeks. Urine samples were collected from cows (n=6–7) on d 0 and 14. The urinary concentrations of ZEN and its metabolites were found to be variable in all herds. This might reflect significant natural ZEN contamination of the feed at the farm level. However, the urinary concentrations of ZEN and its metabolites after supplementation with MAs for 2 weeks were not significantly different. Additionally, our results suggest the possibilities that supplementation of the feed with MA may affect the absorptivity of mycotoxins from the gastrointestinal tract, or limit the binding of MA to mycotoxins.
Preview · Article · Sep 2011 · Journal of Applied Animal Research
[Show abstract][Hide abstract] 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.
No preview · Article · Jan 2011 · Journal of Animal Science
[Show abstract][Hide abstract] ABSTRACT: Zearalenone (Zen) and its metabolites are estrogenic and may be important factors involved in reproductive disorders in domestic animals. We aimed to (1) simultaneously detect Zen and its metabolites in bovine follicular fluids (FFs) by liquid chromatography-tandem mass spectrometry and (2) examine the in vitro effects of Zen on bovine oocytes. Zen and its metabolites were detected in 6 of 32 normal follicles and 7 of 20 cystic follicles. Bovine oocytes were cultured in a maturation media containing various Zen concentrations (0 [control], 1, 10, 100, and 1000microg/L), fertilized, and cultured further. Maturation rates decreased dose-dependently. Further, maturation of 62 (50%) of 124 oocytes examined in the 1000-microg/L group was arrested in metaphase I, without affecting the fertilization rate. Blastocyst-formation rates did not significantly differ among the groups. Zen and its metabolites were detectable in bovine FFs. High Zen concentration may adversely affect meiotic competence but not the fertilization and development rates.
No preview · Article · Sep 2008 · Reproductive Toxicology