title: The effect of methionine and protein deficiency in delaying expulsion of Nippostrongylus brasiliensis in the rat.
abstract: Three protein-deficient diets containing 5%, 6%, or 7% casein, with and without 0.3% methionine supplementation, were fed to Wistar rats from weaning for 6 wk. Animals were infected subcutaneously with 1500 larvae of Nippostrongylus brasiliensis and killed after 14 days when nutritionally normal animals have expelled more than 97% of the worm burden. There was a delay in worm expulsion that was related to both the protein content (p = 0.0006) and to methionine content (p less than 0.0001). Methionine supplementation significantly reduced the worm burden in animals fed the 7% protein diet from a geometric mean of 32.4 to 5.2 (p = 0.0408) and in rats fed the 6% protein diet from a mean of 162 to 8.1 (p = 0.0002) but had no effect in rats on the 5% casein diet. Thus, addition of methionine overcame the adverse effect of protein deficiency in these less severely affected groups.
mesh_terms: D000818:Animals; D001835:Body Weight; D004032:Diet; D007421:Intestine, Small / Q000469:parasitology; D008297:Male; D008715:Methionine / Q000008:administration & dosage / Q000172:deficiency*; D009349:Nematode Infections / Q000276:immunology*; D009559:Nippostrongylus; D011488:Protein Deficiency / Q000276:immunology*; D051381:Rats; D011919:Rats, Inbred Strains; D012709:Serum Albumin / Q000378:metabolism
chemical_list: D012709:Serum Albumin; D008715:Methionine