ABSTRACT
Citrinin (a mycotoxin produced as a frequent contaminant of food and feed by numerous species of Aspergillus and Penicillium fungi) is embryo/fetotoxic and embryocidal in mice and rats. The present study was designed to examine whether the in vivo observed developmental toxicity of citrinin could be recapitulated using the Hydra attenuata (HA) bioassay and then be confirmed in rat whole embryo culture (WEC). Results from the HA assay indicated that the minimal affective concentrations of citrinin required to elicit a toxic response in the adult hydra (MACA) and in the regenerating hydra (MACD) were 30 mg/l and 20 mg/l, respectively. The Hydra developmental hazard index (A/D ratio) was equal to 1.5, classifying citrinin as a coaffective developmental toxin. In WEC, rat embryos were cultured in homologous (rat) serum containing citrinin at various concentrations ranging from 0.0 and 300 micrograms/ml for a period of 45 h. The results indicated a concentration-dependent reduction in yolk sac diameter, crown-rump length, somite number, protein and DNA contents. No embryonic dysmorphogenesis was observed in any treatment group. Histological examination revealed severe diffuse mesodermal and ectodermal necrosis in embryos treated with 250 micrograms/ml citrinin. At lower concentrations of citrinin, embryos were neither grossly nor histologically different from controls. Both the HA and WEC bioassays demonstrated that citrinin is not a primary developmental toxin. The use of HA and WEC bioassays in tandem may facilitate the rapid detection and ranking of the developmental hazards of food and feedborne mycotoxins.
Subject(s)
Citrinin/toxicity , Teratogens/toxicity , Animals , Culture Techniques , Embryo, Mammalian/drug effects , Embryo, Nonmammalian , Embryonic Development , Female , Hydra , Male , Pregnancy , Rats , Rats, Sprague-DawleyABSTRACT
Administration of 3,3',4,4',5-pentachlorobiphenyl (pentaCB) to female C57BL/6 mice at doses from 130.5 to 522 micrograms/kg body weight resulted in the dose-dependent formation of fetal cleft palate and hydronephrosis. The estimated relative potency of 3,3',4,4',5-pentaCB compared to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was in the range of < 0.07-0.04. The immunotoxicity of 3,3',4,4',5-pentaCB and two structurally-related congeners, 3,3',4,4'-tetraCB and 3,3',4,4',5,5'-hexaCB, was investigated in male C57BL/6 mice by determining their suppression of the splenic plaque-forming cell response to sheep red blood cells. The potencies of these compounds relative to TCDD were determined from the ratios of their corresponding ED50 values and were 0.77-0.55 (3,3',4,4',5-pentaCB), 1.1-0.29 (3,3',4,4',5,5'-hexaCB) and 0.14-0.03 (3,3',4,4'-tetraCB). These results demonstrate that the immunosuppressive activities of the PCB congeners relative to TCDD were much higher than observed for many other TCDD-like responses in mice and other laboratory animals.
Subject(s)
Abnormalities, Drug-Induced/etiology , Immunosuppressive Agents/toxicity , Polychlorinated Biphenyls/toxicity , Administration, Oral , Animals , Dose-Response Relationship, Drug , Female , Fetus/abnormalities , Fetus/drug effects , Male , Maternal-Fetal Exchange , Mice , Mice, Inbred C57BL , Polychlorinated Biphenyls/administration & dosage , Polychlorinated Dibenzodioxins/administration & dosage , Polychlorinated Dibenzodioxins/toxicity , Pregnancy , Spleen/drug effectsABSTRACT
Feed grain suspected of causing death in a group of pigs was evaluated for toxic potential in chickens. The contaminated grain sorghum mixture was examined visually and contained 3.7% Cassia occidentalis and 1.6% Cassia obtusifolia seeds by weight. Thirty-two chicks were fed a sample of this suspect grain sorghum mixture. Chickens receiving the contaminated grain lost weight rapidly, exhibited clinical signs typical of intoxication with Cassia spp., and by day 16 were severely debilitated. Necropsy and histologic and electron microscopic examinations demonstrated a skeletal and cardiac degenerative myopathy consistent with intoxication by Cassia occidentalis. These toxicologic investigations verified the toxic potential of the contaminated sorghum mixture for chickens, and these comparative observations support prior diagnostic efforts implicating Cassia spp. as a cause of illness in swine.
Subject(s)
Animal Feed/poisoning , Cassia , Plant Poisoning/veterinary , Plants, Medicinal , Seeds , Swine Diseases/etiology , Animals , Chickens , Edible Grain/poisoning , Food Contamination , Microscopy, Electron , Muscles/pathology , Myocardium/pathology , Myocardium/ultrastructure , Plant Poisoning/etiology , Plant Poisoning/pathology , Poultry Diseases/etiology , Poultry Diseases/pathology , Swine , Weight LossABSTRACT
Brunfelsia calcyina var. floribunda is an ornamental evergreen shrub found in the United States. A diagnosis of the fatal intoxication of a canine due to consumption of plant material (primarily berries) was made. The significant features of the clinical constellation were similar to those seen with substances interfering with the neurotransmission process, such as lathyrus or strychnine. Necropsy findings on the canine were unrevealing. Toxicologic studies performed on mice and rats with ground shrub material demonstrated that all parts of this plant are toxic, but unequally so. All plant preparations produced signs similar to those of a spinal convulsant. There were no distinguishing gross pathologic or histopathologic findings associated with the toxicoses induced in the laboratory animals with preparations from this plant. The toxic principles from this shrub are water soluble and very stable. The ability of aqueous extracts stored at 4 C to produce the clinical syndrome and subsequent lethality remained unchanged over a period of 4 months. Exposures are not always fatal. They most often occur in the canine and there is a significant hazard for small children.
