These results are similar to the presented data. Apparently the host environmental changes caused by malnutrition or by STZ-induced IDDM have either an effect on the worm's ability to produce viable eggs, or on the development of the egg in the intestine tissue. Metabolic changes caused by diabetes or malnutrition could thus affect the maturation in the host tissue. Microvascular intestinal changes associated to the diabetic state for instances might play a role. Nevertheless it seems more likely that production of viable eggs by the female worm is affected.
Most eggs are already dead in the first stage of their development.
Non-enzymatic glycosylation of proteins due to hyperglycaemia cannot be discarded to influence the reproductive capacity of the female worm or the ability of the egg to mature. Inducing diabetes mellitus with streptozotocin in mice infected with S. mansoni resulted in a lower number of eggs per gram faeces and a lower amount of mature and viable eggs in the intestine tissue. The total amount of eggs in the intestine and the amount of worms recovered was not affected. The lower faecal egg excretion in diabetic mice is thus caused by impaired egg maturation.