Toxicopathological alterations induced by high dose dietary T-2 mycotoxin and its residue detection in Wistar rats

T-2 toxin is one of the most potent cytotoxic and food-borne mycotoxins. Most experimental studies on the T-2 toxin have been performed at extremely low doses (ppb level). However, several field reports of contaminated feed have shown concentration of T-2 toxin to be as high as ≥20 ppm. Therefore, the impact of high dose T-2 toxin (20 ppm) after subacute exposure was investigated in an experimental setup with respect to growth performance, oxidative stress, and detailed pathomorphology in young male Wistar rats. Furthermore, to see the effect of such a high dose on the accumulation of T-2 toxin, its residues in various organs were quantified by high-performance thin-layer chromatography (HPTLC). Apart from obvious clinical toxicosis, rats in the toxin-fed group showed significant hemato-biochemical alterations and increased levels of biological markers of oxidative stress with concomitant decrease in levels of serum and tissue catalase and superoxide dismutase. These alterations were strongly supported by histopathological changes, such as hyperkeratosis and hyperplasia of the squamous gastric mucosa, oxidative damage to hepatocytes, atrophy of the thymus and spleen, and overall decrease in the spermatogenic activity of testes. An economical, simple, reliable, and quick method for the detection and quantification of T-2 toxin residues by HPTLC is also reported here. No residual T-2 toxin was detected in any of the organs tested, suggesting that T-2 toxin does not accumulate in tissues even at such a high exposure level.

Disturbance of oxidant/antioxidant equilibrium in horses naturally infected with Trypanosoma evansi

Oxidant/antioxidant equilibrium disturbance has already been reported in trypanosome infections by several authors. The present study was aimed to explore the possible oxidant/antioxidant disturbance in surra of naturally infected horses before and after treatment. Fifteen naturally infected horses were chosen to analyse erythrocytic indices, platelet counts, lipid peroxides (LPO), nitric oxide (NO), reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) while six healthy animals acted as control. There was a highly significant (P<0.001) reduction in red blood cell (RBC) count, haemoglobin (Hb), packed cell volume (PCV) and platelet levels and a significant reduction in mean corpuscular haemoglobin concentration (MCHC) (P<0.05) was noticed. A highly significant increase in NO (P<0.001), a significant increase in LPO (P<0.05) and a significant decrease in GSH, SOD and CAT (P<0.05) were found. A negative correlation of RBC count with LPO (r=-0.844) and nitrate (r=-0.702) while a positive correlation with GSH (r=0.489), SOD (r=0.580) and CAT (r=0.689) was observed. All the animals were treated with Quinapyramine sulphate (3mg/kg s.c.) only once. Nine animals recovered completely without any side effects. The recovered animals were monitored and samples were collected every seven days for up to 21 days and parameters were analysed. After treatment, a significant increase in haematological parameters was noticed whereas the oxidative indices varied without any statistical significance. To conclude, the increase in oxidant parameters and decrease in antioxidant enzymes in infected horses indicates the disturbance of oxidant/antioxidant indices. There was a significant increase in post therapy haematological values, while the oxidant/antioxidant indices changed insignificantly indicating that antioxidants might be supplemented in the therapeutic regimen.