Summary
The availability of dietary cadmium in the form of CdCl2 was compared with the availability of cadmium naturally incorporated in the feeding yeast. The effect of feeding yeast on the availability of supplemented CdCl2 was also assessed. Seventy‐two weaned male Wistar rats were used in a randomized complete block design with six littermates per block. Animals within the block were randomly assigned to experimental groups and one animal was assigned to a group euthanized to establish the initial trace element status in the organs. The experimental groups included: 1. control, standard diet (Cd, 0 mg/kg); 2. diet with 10% yeast of low Cd concentration (Cd, 0.3 mg/kg); 3. diet with 10% yeast of high Cd concentration (Cd, 6 mg/kg); 4. diet with 10% yeast of low Cd concentration + CdCl2 (Cd, 6 mg/kg); 5. standard diet + CdCl2 (Cd, 6 mg/kg). Animals had ad libitum access to water and feed for the entire duration of the experiment (8 weeks). Body weight gain and feed consumption were recorded. At the end of the experiment, animals were euthanized and the duodenum, liver, and kidney were sampled. Cadmium concentrations in the tissue samples were determined using atomic absorption spectrophotometry after dry ashing of the samples. There was an obvious increase of cadmium concentration in the organs of animals that were fed diets with elevated cadmium concentrations (experimental groups 3, 4, 5). Among these groups, no significant differences were found in cadmium concentrations in the liver and kidney. However, cadmium concentrations in the duodenum differed significantly, with the highest cadmium concentration found in animals from group 5 (CdCl2 supplement, no yeast) which suggests a higher availability of dietary cadmium in the form of CdCl2 compared to cadmium incorporated in the feeding yeast. While zinc and copper concentrations in the organs examined remained unaffected by the experimental treatments, dietary cadmium reduced the iron concentrations in the duodenum and liver and this effect seemed to be alleviated by the presence of yeast in the diet. Different dietary treatments also caused differences in the liver concentrations of manganese.
Zusammenfassung
Der Einfluß von organischem und anorganischem Diät‐Cadmium auf die Verfügbarkeit von Cadmium, Zink, Kupfer, Eisen und Mangan bei Ratten
Die Verfügbarkeit von Cd aus Nahrungsmitteln, die mit CdCl2 versetzt waren, wurde mit der Verfügbarkeit von natürlich aufgenommenem Cd aus Futtermittelhefe verglichen. Der Einfluß von Futtermittelhefe mit zugesetztem CdCl2 wurde auch untersucht. Zweiundsiebzig entwöhnte Wistar Ratten wurden zufällig durch ein vollständiges Block‐design mit jeweils 6 Würfen pro Block ausgewählt. Tiere innerhalb eines Blocks wurden zufällig den experimentellen Gruppen zugeordnet. Ein Tier wurde getötet, um die Ausgangskonzentrationen der Spurenelemente in den Organen zu bestimmen. Die Versuchsgruppen beinhalten: 1. Kontroll – Standardfutter mit (Cd, 0,0 mg/kg), 2. Futter mit 10% Hefe mit niedriger Cd‐Konzentration Cd (Cd, 0,3 mg/kg); 3. F...