The function of the intestine in the pulmonate mollusc Helix pomatia L

Studies on the effects of dietary beryllium at two different calcium concentrations in Achatina fulica (Pulmonata)

The mortality was highest in snails fed beryllium in the diet containing the sub-optimal concentration of calcium. There was no increase in weight over an 8 week period. Snails fed the diet containing the optimal concentration of calcium without added beryllium showed maximum weight increase but calcium alone may not be responsible for elevated growth rate. Dietary calcium enhancement appears to be responsible for the reduced concentration of zinc, magnesium, phosphate and beryllium in the tissues. Beryllium treatment did not affect the calcium concentration in the digestive gland tissue but increased zinc and magnesium in the shell. The results are discussed in relation to uptake studies and possible enzyme systems involved.

Effect of chronic and acute lead treatment in the slug Arion ater on calcium and delta-aminolaevulinic acid dehydratase activity

Accumulation of lead in the tissues was greater after acute exposure. Most of the metal was deposited in the intestine and least in foot. After chronic exposure to lead the calcium content of the intestine decreased. After chronic and acute exposure to lead the calcium content of the digestive gland and foot was lower than control values. Lead in the digestive gland granules was higher after acute lead treatment. Less than 45% of the lead was associated with the granules. These results are discussed in view of the difference in metabolism and chemical nature of the organs investigated. ALAD activity was located in the digestive gland and it was reduced after acute treatment with lead.