Pannon White (n512) male rabbits (weight: 4050 to 4500 g, age: 9 months) received 2ml of a suspension containing purifiedudT-2 toxin by gavage for 3 days. The daily toxin intake was 4 mg/animal (0.78 to 0.99 mg/kg body weight (BW)). Control animalsud(n512) received toxin-free suspension for 3 days. Since a feed-refusal effect was observed on the second day after T-2udadministration, a group of bucks (n510) were kept as controls (no toxin treatment) but on a restricted feeding schedule,udthat is, the same amount of feed was provided to them as was consumed by the exposed animals. On day 51 of the experimentud(i.e. 48 days after the 3-day toxin treatment), semen was collected, and pH, concentration, motility and morphology of theudspermatozoa, as well as concentration of citric acid, zinc and fructose in the seminal plasma, were measured. After gonadotropinreleasingudhormone (GnRH) analogue treatment, the testosterone level was examined. One day of T-2 toxin treatment dramaticallyuddecreased voluntary feed intake (by 27% compared to control, P,0.05) and remained lower ( P,0.05) during the first 2 weeksudafter the withdrawal of the toxin. BW of the contaminated rabbits decreased by 88% on days 17 and 29 compared to controlsud( P,0.05). No effect of toxin treatment was detected on pH and quantity of the semen or concentration of spermatozoa. Theudratio of spermatozoa showing progressive forward motility decreased from 65% to 53% in the semen samples of toxin-treatedudanimals compared to controls ( P.0.05). The ratio of spermatozoa with abnormal morphology increased ( P,0.05) in theudejaculates collected from the toxin-treated animals. T-2 toxin applied in high doses decreased the concentration of citric acid inudseminal plasma ( P,0.05). No effect of T-2 toxin on the concentrations of the other seminal plasma parameters (fructose andudzinc) was observed. T-2 toxin decreased the basic testosterone level by 45% compared to control ( P,0.01) and resultedudin lower ( P,0.05) GnRH-induced testosterone concentration. Feed restriction, that is, less nutrient intake, resulted in moreudmorphologically abnormal spermatozoa in the semen, but it did not cause significant loss in BW, motility of the spermatozoa,udcomposition of the seminal plasma or testosterone concentration – its effect needs further examination.
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