The Effect of Mycotoxin Deoxynivalenol on Haematological and Biochemical Indicators and Histopathological Changes in Rainbow Trout (Oncorhynchus mykiss)

Abstract

Deoxynivalenol (DON), produced by the Fusarium genus, is a major contaminant of cereal grains used in the production of fish feed. The effect of mycotoxin deoxynivalenol on rainbow trout (Oncorhynchus mykiss) was studied using a commercial feed with the addition of DON in a dose of 2 mg/kg feed. The fish (n = 40) were exposed to the mycotoxin for 23 days. The trout were divided into two groups, control and experimental groups. Control groups were fed a commercial feed naturally contaminated with a low concentration of DON (225 μg/kg feed); experimental groups were fed a commercial feed with the addition of DON (1964 μg/kg feed). Plasma biochemical and haematological indices, biometric parameters, and histopathological changes were assessed at the end of the experiment. The experimental groups showed significantly lower values in MCH (P < 0.05). In biochemical indices, after 23-day exposure, a significant decrease in glucose, cholesterol (P < 0.05), and ammonia (P < 0.01) was recorded in the experimental group compared to the control group. Our assessment showed no significant changes in biometric parameters. The histopathological examination revealed disorders in the caudal kidney of the exposed fish. The obtained data show the sensitivity of rainbow trout (O. mykiss) to deoxynivalenol.

Effect of the mycotoxin deoxynivalenol on the immune responses of rainbow trout (Oncorhynchus mykiss)

“…A recent investigation of zebrafish Danio rerio fed DON at concentrations of 0.1-3 mg/kg feed showed higher levels of genetic liver biomarkers and an influence on the reproductive system (Sanden et al 2012). In a previous study we found changes in haematological and biochemical parameters, including pathological alterations in caudal kidney, of rainbow trout fed DON at 2 mg/kg feed (Matejova et al 2014). Woodward et al (1983) found that diets containing 1.0-12.9 mg/kg DON depressed feed intake and weight gain and decreased feed conversion efficiency of juvenile rainbow trout.…”

“…No morbidity and mortality was recorded during the study. The same animals were used as in an already published study (Matejova et al 2014).…”

“…The commercial diet (BioMar, Denmark) contained rapeseed oil, blood meal, fish meal, soya cake, sunflower cake, rapeseed meal, horse beans, wheat, soya concentrate, fish oil, pea protein, vitamins, and minerals based on the manufacturer's information. The experimental diet contained DON (Sigma-Aldrich, USA) at 2 mg/kg, as previously described (Matejova et al 2014). The leaching of DON from experimental diets probably did not influence its intake, as fish in all groups consumed the pellets within 20 min.…”

Elevated concentrations of T-2 toxin cause oxidative stress in the rainbow trout (Oncorhynchus mykiss)

“…These equivalents were prepared in place of 3 mg and 5.4 mg, respectively as up to 33% loss of T2‐toxin was expected during the preparation of pellets with such a small amount of active substance. This level of loss has been experimentally verified when preparing pellets by the same method with other substances (Matejova et al., , ).…”

Impact of Mycotoxins on Aquaculture Fish Species: A Review

“…After 23‐d exposure to DON in a concentration of 2.0 mg/kg, rainbow trout showed severe hyaline droplet degeneration in tubular epithelial cells of the renal tubules in the caudal kidney. Although no significant changes in biometric parameters were recorded, significant changes in hematological parameters, such as lower mean corpuscular hemoglobin values, and biochemical parameters, such as a decrease in glucose, cholesterol, and ammonia, were observed (Matejova et al ).…”