An evaluation of two animal models for dietary influences on reproductive toxicology

Chronic protein deficiency (8 weeks) was examined in marmosets (Callithrix jacchus) and sub-acute (1 week) methionine- and choline-deprivation was investigated in F344 rats. The marmosets were considered to have become protein-deficient but there was no alteration in sperm morphology, either at the end of the diet or 5 weeks later. Weight loss was also observed in rats on the methionine- and choline-free diet and they had significantly decreased sperm counts 4 weeks after the end of treatment. However, there was no effect on sperm morphology, or on the proportion of cytosine residues that were methylated in the sperm DNA.