Individual and combined effect of Fusarium toxins in vivo

Feed containing fumonisin (5 ppm; F), zearalenone (Z) and deoxynivalenol (D) (0.25 ppm+1 ppm; ZD) individually and these three toxins in combination (5 ppm+0.25 ppm+1 ppm; FZD) was fed to adult Pannon White (n =15/group) male rabbits (4±0.5 kg) for 65 days to determine the Fusarium toxin eff ect on breeding rabbit bucks’ sperm quality and endocrine function. Th e toxin levels were the lowest limit values for farm animals of the Commission Recommendation (2006/576/EC). On trial days 0, 30 and 65 blood and semen were sampled, and from semen pH, concentration, motility and morphology of the spermatozoa were investigated. Th e ratio of spermatozoa showing progressive forward motility decreased (P<0.05) from 80% to 67% in the FZD group. Diff erences were found between the data of the ZD (66.3%±23.7) and control animals (80.2%±11.2) concerning the normal morphology of spermatozoa. Aft er gonadotropin-releasing hormone analogue treatment, the testosterone concentration was lowered in the FZD animals aft er 65 days. Th ere was no diff erence among groups in feed consumption and BW. Histophatology revealed lowered spermiogenesis activity occurred in lower percentage in the ZD group (30.77%), while in FZD it was much more progressed (64.28%), referring to a synergistic eff ect of the three toxins

Effect of dietary supplementation of spirulina (arthrospira platensis) and thyme (thymus vulgaris) on serum biochemistry, immune response and antioxidant status of rabbits

Growing rabbits’ (42 rabbits/group, 3 rabbits/cage, 14 cages/treatment) diet was supplemented with 5% Spirulina (Arthrospira platensis) and 3% thyme (Thymus vulgaris L.) powder single (S or T) and in combination (ST) between 35 and 77 days of age. On day 0 (weaning at 35 days of age) 14 rabbits were vaccinated with 100 µg/animal ovalbumin to provoke immune response. Blood samples were taken on days 0, 14, 28 and 42 of the experimental period. Sampling dates significantly influenced total protein, albumin, glucose, cholesterol, urea, creatinine concentration and enzyme (AST, ALT, GGT) activities, with a significant age × diet interaction in the case of TP and CREA. There was a significant increase in ALT (+45 and 74%) and GGT (+87 and 102%) activity after immunisation. While Spirulina and thyme significantly ameliorated the rise in AST activity, their effect was inefficient in the case of GGT. Spirulina, both single and in combination showed a tendency in higher IgG level as compared to control (P<0.05). No significant effect of sampling date or treatment on phagocytic activity or secretory IgA was demonstrable (P>0.05). Higher MDA concentration was measured in the red blood cells of S, T and ST animals, while no other significant diet effect on the antioxidant parameters was detected, however, significant sampling date × diet interaction was found in the case of GPx activity. Plasma GGT (increase by 19–66%) was inversely associated with GSH (decrease by 66–113%) between days 0 to 42 of the experimental period (r=–0.57, P<0.05). It can be concluded that Spirulina supplementation alone resulted in higher IgG production, but none of the phytobiotics, at the dose used, affected significantly the antioxidant status of bloo

Effect of chronic T-2 toxin exposure in rabbit bucks, determination of the No Observed Adverse Effect Level (NOAEL)

T-2 toxin (T-2) was administered to adult Pannon White (n = 10/group) male rabbits for 65 days, first in a suspension by gavage (0.05, 0.1 or 0.2 mg/animal/day), and secondly mixed into the feed (0.33 and 0.66 mg/kg feed). In the first experiment 0.1 mg T-2 exposure resulted in temporary decrease in feed intake, slower increase in the gonadotropin-releasing hormone (GnRH) induced testosterone synthesis, slight centrolobular infiltration in the liver and a slight hyperplasia of the Leydig cells. In addition to the temporary feed refusal effect, 0.2 mg T-2 caused a temporary decrease in plasma albumin and urea concentrations, lesser glutathione peroxidase (GPx) activity in the seminal plasma, a greater (by 320%) ratio of spermatozoa with cytoplasmic droplets, slower increase in the GnRH-induced testosterone synthesis, centrolobular infiltration in the liver, slightly hyperaemic testes and increased proliferative activity of the Leydig cells. The two smaller doses applied in feed (0.33 and 0.66 mg/kg) did not cause any significant adverse effect, and no feed refusal was observed. According to these results the No Observed Adverse Effect Level (NOAEL) of T-2 for adult rabbit males was found to be <0.1 mg/animal/day (<0.02 mg/kg b.w./day)

Preliminary Results on the Effect of Chronic T-2 Toxin Exposure in Rabbit Bucks

The aim of the present study was to examine the chronic effect of T-2 toxin on feed consumption and sperm quality. Pannon White (n=10/group) male rabbits (weight: 4050-4500 g, age: 9 month) trained to ejaculate into artificial vagina were exposed to 0 (control), 0.05, 0.1 or 0.2 mg/animal/day of T-2 toxin by gavage for 63 days. On the 63rd day of the experiment semen was collected with an artificial vagina, and the following traits were evaluated: pH, concentration, morphology, motility with CASA, concentration of seminal plasma components such as citric acid, zinc and fructose. At the end of the experiment animals were necropsied and the testes were subjected to histopathological examination. T-2 toxin in 0.1 mg and 0.2 daily dose significantly decreased feed intake in the first two weeks but no significant difference between groups were observed from the 4th week. Among the sperm quality traits examined only the ratio of spermatozoa with cytoplasmic droplets increased by 320% in animals treated with the highest dose of T-2. The 0.1 mg/animal/day toxin exposure resulted in a slight hyperplasia of the Leydig cells, while the highest dose (0.2 mg/animal/ day) caused hyperaemia, increased proliferative activity and hyperplasia of the Leydig cells. According to the preliminary results it seems, that adult male rabbits may tolerate the concentration of 0.05 mg/animal/day T-2 toxin