Growth and estrous activity of rats fed adequate and deficient levels of phosphorus.
Female Sprague-Dawley rats were fed two levels of phosphorus ad libitum and in a paired feeding arrangement to yield the following three treatments: adequate phosphorus (0.40%) ad libitum intake, low phosphorus (0.04%) ad libitum intake and adequate phosphorus pair-fed with the low phosphorus group. Feed intake, growth rate and feed conversion in rats fed 0.04% phosphorus ad libitum and in pair-fed control rats were lower (P less than 0.01) than in rats fed 0.40% phosphorus ad libitum. Seventy-five percent of the rats exhibited normal estrous cycles, as indicated by vaginal smears, throughout the 105-d period regardless of dietary phosphorus level. Breeding efficiency and number of pups per litter were not altered by dietary treatment. However, compared to either phosphorus-adequate group, dams fed 0.04% phosphorus weaned fewer (P less than 0.05) pups and pup survival to 45 d of age was lower (P less than 0.05). Average daily gain postweaning was 67% lower for pups in the phosphorus-deficient group than for those in either phosphorus-adequate group. Phosphorus deficiency in rats does not alter estrous cycles but reduces pup survivability postnatally.
D000818:Animals; D001724:Birth Weight; D002118:Calcium / Q000008:administration & dosage; D004032:Diet; D004044:Dietary Proteins / Q000008:administration & dosage; D002149:Energy Intake; D004971:Estrus; D005260:Female; D006128:Growth; D008431:Maternal-Fetal Exchange; D010758:Phosphorus / Q000008:administration & dosage / Q000172:deficiency*; D011247:Pregnancy; D051381:Rats; D011919:Rats, Inbred Strains; D012098:Reproduction
D004044:Dietary Proteins; D010758:Phosphorus; D002118:Calcium